Support assembly and keyboard apparatus

A support assembly according to one embodiment of the present invention is provided, the support assembly including a jack rotatably supported by a support; a repetition lever rotatably supported with respect to the support; a protrusion disposed at an intersecting portion of the jack and the repetition lever; and a protrusion receiving portion for receiving the protrusion; wherein the protrusion receiving portion defines a movable range of the protrusion and limits a rotation range of the jack.

CROSS REFERENCE TO RELATED APPLICATIONS

This application is based upon and claims the benefit of priority from the prior Japanese Patent Application No. 2015-204534, filed on Oct. 16, 2015, and PCT Application No. PCT/JP2016/078151, filed on Sep. 26, 2016, the entire contents of which are incorporated herein by reference.

FIELD

The present invention relates to a support assembly for use in a keyboard apparatus.

BACKGROUND

Conventional acoustic pianos such as grand pianos and upright pianos are configured of many components. Also, since assembling these components is very complex, the assembling operation takes a long time. In particular, since an action mechanism provided for each key requires many components, its assembling operation is very complex.

For example, in an action mechanism described in Japanese Patent Application Laid-Open No. 2005-292361, a plurality of components operate together, and key operation by key pressing and key releasing is transmitted to a hammer. In particular, a support assembly configuring part of the action mechanism operates with various components assembled together. The support assembly has not only a mechanism which achieves string hammering by the hammer in accordance with key pressing but also an escapement mechanism for releasing a force transmitted to the hammer by key operation immediately before string hammering. This mechanism is an important mechanism for the basic operation of an acoustic piano. In particular, in a grand piano, a double escapement mechanism with a repetition lever and a jack combined together is generally adopted.

The operation of the action mechanism provides a sense (hereinafter referred to as a touch feeling) to a finger of a player through the key. In particular, the structure of the support assembly has an important influence on the touch feeling. For example, the touch feeling by the operation of the escapement mechanism is called let-off.

SUMMARY

Since the number of respective components making up the support assembly is large, the manufacturing period is prolonged, and manufacturing cost increased. Therefore, to reduce manufacturing cost, it is desired to simply decrease the number of components and simplify the structure. However, if the structure of the support assembly is changed, the touch feeling at the time of key operation is greatly changed. Therefore, it is difficult to decrease the expense of manufacturing an acoustic piano.

One object of the present invention is to reduce manufacturing cost of a support assembly while decreasing a change in touch feeling at the time of key operation, compared with a keyboard apparatus of an acoustic piano.

According to one embodiment of the present invention, a support assembly is provided, the support assembly including a jack rotatably supported by a support; a repetition lever rotatably supported with respect to the support; a protrusion disposed at an intersecting portion of the jack and the repetition lever; and a protrusion receiving portion for receiving the protrusion; wherein the protrusion receiving portion defines a movable range of the protrusion and limits a rotation range of the jack.

The protrusion may define a movable range of the protrusion receiving portion and limit a rotation range of the repetition lever.

A range of the protrusion receiving portion in which the protrusion moves may define a movable range of the jack at time of key pressing and time of key releasing.

The protrusion receiving portion may be a groove or an opening, and a contacting surface to be brought into contact with the protrusion may be made from a soft material.

The protrusion may be disposed on the jack, and the protrusion receiving portion may be disposed on the repetition lever.

The support may include a resin made structure.

The jack may include a resin made structure.

According to one embodiment of the present invention, a keyboard apparatus is provided, the keyboard apparatus including a plurality of support assemblies according to any one of the above; a key disposed for each of the support assemblies and provided for rotating the support; and a sound emission mechanism for emitting sound in accordance with pressing of the key.

The sound emission mechanism may include a sound source unit for generating a sound signal according to a key pressing operation.

The sound emission mechanism may include a string generating a sound by being struck by a hammer in accordance with key pressing operation.

REFERENCE SIGNS LIST

DESCRIPTION OF EMBODIMENTS

In the following, a keyboard apparatus including a support assembly in one embodiment of the present invention is described in detail with reference to the drawings. Embodiments described below are merely examples of embodiments of the present invention, and the present invention should not be interpreted to be restricted to these embodiments. Note that, in the drawings referred to in the present embodiments, identical portions or portions having a similar function are provided with a same sign or similar sign (sign with a numeral merely followed by A, B, or the like), and repetitive description thereof may be omitted. Also, for convenience of description, the dimensional ratio in the drawings (such as ratio between respective structures, or a ratio among length) may differ from an actual ratio, and part of the structure may be omitted from the drawings.

First Embodiment

A keyboard apparatus1in a first embodiment of the present invention is an example obtained by applying one example of the support assembly according to the present invention to an electronic piano. To obtain a touch feeling close to a grand piano at the time of key operation, this electronic piano includes a structure similar to a support assembly included in a grand piano. By usingFIG. 1, a general outline of the keyboard apparatus1according to the first embodiment of the present invention is described.

FIG. 1is a side view depicting a mechanical structure of the keyboard apparatus according to the first embodiment of the present invention. As depicted inFIG. 1, the keyboard apparatus1according to one embodiment of the present invention includes a plurality of keys110(in this example, eighty-eight keys) and an action mechanism for each of the keys110. The action mechanism includes a support assembly20, a hammer shank310, a hammer320, and a hammer stopper410. Note that whileFIG. 1depicts the case in which the key110is white key, the key may be a black key. Also, in the following description, terms representing orientations such as a forward side, a deeper side, upward, downward, and sideward from a player are defined as orientations when the keyboard apparatus is viewed from a player's side. For example, in the example ofFIG. 1, the support assembly20is disposed on a player's forward side when viewed from the hammer320, and is disposed upward when viewed from the key110. Sideward corresponds to a direction in which the keys110are arranged.

The key110is rotatably supported by a balance rail910. The key110rotates in a range from a rest position depicted inFIG. 1to an end position. The “rest position” is a key position when the key is not pressed, and the “end position” is a key position when the key is fully pressed. The key110includes a capstan screw120. The support assembly20is rotatably connected to a support flange290, and is resting on the capstan screw120. The support flange290is fixed to a support rail920. Detailed structure of the support assembly20will be described further below. Note that the support flange290and the support rail920are one example of a frame serving as a reference of rotation of the support assembly20. The frame may be formed of a plurality of members, such as the support flange290and the support rail920, or may be formed of one member. The frame may be, as with the support rail920, a rail-shaped member with a long side in the arrangement direction of the keys110, or may be, as with the support flange290, an independent member for each key110.

The hammer shank310is rotatably connected to a shank flange390. The hammer shank310includes a hammer roller315. The hammer shank310is mounted on the support assembly20via the hammer roller315. The shank flange390is fixed to a shank rail930. The hammer320is fixed to an end of the hammer shank310. A regulating button360is fixed to the shank rail930. The hammer stopper410is fixed to a hammer stopper rail940and disposed at a position of regulating rotation of the hammer shank310.

A sensor510is a sensor for measuring the position and moving speed (in particular, speed immediately before the hammer shank310collides with the hammer stopper410) of the hammer shank310. The sensor510is fixed to a sensor rail950. In this example, the sensor510is a photo interrupter. In accordance with the amount of shielding the optical axis of the photo interrupter by a shielding plate520fixed to the hammer shank310, an output value from the sensor510is changed. Based on this output value, the position and moving speed of the hammer shank310can be measured. Note that a sensor for measuring an operating state of the key110may be provided in place of the sensor510or together with the sensor510.

The above-described frame920, shank rail930, hammer stopper rail940, and sensor rail950are supported by a bracket900.

[Structure of Support Assembly20]

FIG. 2is a side view depicting the structure of the support assembly in the first embodiment of the present invention.FIG. 3is a perspective view depicting the structure of the support assembly in the first embodiment of the present invention.FIGS. 4A and 4Bare side views depicting a partial structure of the disassembled support assembly in the first embodiment of the present invention. For easy understanding of the features of each component,FIG. 4Ais a drawing in which a jack250and a torsion coil spring280are excluded from the support assembly20.FIG. 4Bis a drawing only depicting the jack250.

The support assembly20includes a support210, a repetition lever240, the jack250, and the torsion coil spring280. The support210and the repetition lever240are coupled together via a flexible portion220. By the flexible portion220, the repetition lever240is rotatably supported with respect to the support210. The support assembly20, except the torsion coil spring280and cushioning materials or the like (such as elastic body etc.) provided at a portion which collides with another member, is a resin-made structure manufactured by injection molding. In this example, the support210and the repetition lever240are integrally formed. Note that the support210and the repetition lever240may be formed as individual components and be attached or bonded together.

The support210has one end side where a through hole2109is formed, and has the other end side where a jack support portion2105is formed. Between the through hole2109and the jack support portion2105, the support210includes a support heel212projecting downward and a spring support portion218projecting upward. Through the through hole2109, a shaft supported by the support flange290is drawn. With this, the support210is rotatably disposed with respect to the support flange290and the support rail920. Therefore, the through hole2109serves as a rotation center of the support210.

The support heel212makes contact with the above-described capstan screw120at its lower surface. The spring support portion218supports the torsion coil spring280. The jack support portion2105rotatably supports the jack250. Therefore, the jack support portion2105serves as a rotation center of the jack250.

Between the through hole2109(rotation center of the support210) and the jack support portion2105(rotation center of the jack250), a space SP is formed on a jack support portion2105side from the support heel212. For convenience of description, the support210is sectioned into regions: a first main body portion2101, a bent portion2102, and a second main body portion2103, from the through hole2109side. In this case, by the bent portion2102which couples the first main body portion2101and the second main body portion2103together, the second main body portion2103is disposed on a side closer to the key110(downward) than the first main body portion2101. The jack support portion2105projects upward from the second main body portion2103. According to this sectioning, the above-described space SP corresponds to a region interposed between the bent portion2102and the jack support portion2105above the second main body portion2103. Also, at an end of the support210(an end on a second main body portion2103side), a stopper216is coupled. The support heel212is disposed below the bent portion2102. Here, it is desired that a distance from the key110to the second main body portion2103be longer than a distance from the key110to the support heel212(that is, the length of the capstan screw120). This makes the capstan screw120easily adjustable from a player's side.

To the repetition lever240, a spring contact portion242and an extension portion244are coupled. The spring contact portion242and the extension portion244are extended from the repetition lever240toward the support210side. The spring contact portion242makes contact with a first arm2802of the torsion coil spring280. The repetition lever240and the extension portion244include two plate-shaped members for interposition from sides of both side surfaces of the jack250. In this example, the extension portion244and the jack250slidably make contact with each other in at least part of a space interposed between these two plate-shaped members.

The extension portion244includes an inner portion2441, an outer portion2442, and a coupling portion2443. The inner portion2441is coupled to the repetition lever240on a player's deeper side (flexible portion220side) of a large jack (first jack)2502. At a portion where the inner portion2441and the repetition lever240are coupled together, a rib246is provided. The inner portion2441interposes the large jack2502to cross to extend to a player's forward side (opposite side to the flexible portion220) of the large jack2502. That is, this can also be said that the extension portion244crosses the jack250. At a portion of the intersection between the inner portion2441and the large jack2502, the inner portion2441includes a linear-shaped convex portion P1projecting to a large jack2502side.

A protrusion2510is disposed at the intersecting portion CP of the jack250and the repetition lever240. Furthermore, a protrusion receiving portion2450for receiving the protrusion2510is disposed at the intersecting portion CP. The protrusion receiving portion2450regulates a movable range of the protrusion2510and limits a rotation range of the jack250.

The outer portion2442is coupled to the repetition lever240on a player's forward side (opposite side to the flexible portion220) of the jack250(large jack2502). The inner portion2441and the outer portion2442are coupled together at the coupling portion2443. The coupling portion2443interposes a small jack (second jack)2504.

The jack250includes the large jack (first jack)2502(first jack) and the small jack (second jack)2504. The jack250is rotatably disposed with respect to the support210. Between the large jack2502and the small jack2504, a support connecting portion2505to be rotatably supported by the jack support portion2105is formed. The support connecting portion2505has a shape surrounding part of the jack support portion2105, and regulates a rotation range of the jack250. Also, with the shape of the support connecting portion2505and elastic deformation of its material, it is possible to fit the support connecting portion2505of the jack250into the jack support portion2105from above the jack support portion2105. The large jack2502includes a spring contact portion2562at its lower side surface. The spring contact portion2562makes contact with a second arm2804of the torsion coil spring280.

The large jack2502includes linear-shaped convex portions P2projecting from both side surfaces. The convex portions P2slidably contact the convex portions P1of the inner portion2441described above. The small jack2504includes circular-shaped convex portions P3projecting from both side surfaces. The convex portions P3slidably contact an inner surface of the coupling portion2443described above. The support connecting portion2505includes circular-shaped convex portions P4, P5at its periphery on the side surface of the jack250. In this example, the convex portions P4, P5are provided on a first member2112side of both side surfaces, and are not provided on a second member2114side. The convex portions P4, P5slidably contact the first member2112of a guide portion211disposed at the periphery of the jack support portion2105.

The contact area can be decreased by bringing the jack250and the extension portion244into slidable contact by way of the convex portions P1, P2, and P3. Furthermore, the contact area can be decreased by bringing the jack250and the guide portion211(first member2112) into slidable contact by way of the convex portions P4, P5disposed on the side surface of the jack250. The jack250(periphery of support connecting portion2505) and the second member2114are, on the other hand, directly brought into contact and slidably contact. In this example, the second member2114has a size same as the convex portions P4, P5, and thus the contact area of the jack250(periphery of support connecting portion2505) and the second member2114can be decreased without providing the convex portion. Note that a grease reservoir may be formed by forming a groove portion by a plurality of convex portions P2. Also, a convex portion or groove portion may be formed in a side-surface of the large jack2502.

In the torsion coil spring280, the spring support portion218is taken as a fulcrum, the first arm2802makes contact with the spring contact portion242, and the second arm2804makes contact with the spring contact portion2562. The first arm2802functions as an elastic body which provides a rotational force to the repetition lever240via the spring contact portion242so as to move a player's side of the repetition lever240upward (in a direction away from the support210). The second arm2804functions as an elastic body which provides a rotational force to the jack250via the spring contact portion2562so as to move the large jack2502downward (to a support210side).

FIGS. 5A and 5Bare side views for describing the movement of the support assembly in the first embodiment of the present invention.FIG. 5Ais a side view of the support assembly20at the time of key releasing, andFIG. 5Bis a side view of the support assembly20at the time of key pressing. In the support assembly20, the jack250is rotatably supported by the support210, and the repetition lever240is rotatably supported with respect to the support210. The protrusion2510is disposed at the intersecting portion CP of the jack250and the repetition lever240. Furthermore, a protrusion receiving portion2450for receiving the protrusion2510is disposed at the intersecting portion CP. InFIGS. 5A and 5B, the protrusion2510is disposed on the large jack2502located at the intersecting portion CP, and the protrusion receiving portion2450is disposed at the extension portion244connected by being extended from the repetition lever240located at the intersecting portion CP. The protrusion receiving portion2450defines a movable range of the protrusion2510. Thus, the rotation range of the jack250is limited by the protrusion receiving portion2450.

In the present embodiment, the rotation range of the jack250is determined to a predetermined range by disposing the protrusion2510and the protrusion receiving portion2450at the intersecting portion CP of the jack250and the repetition lever240. In other words, the range in a direction from the deeper side toward the forward side of the player of the protrusion receiving portion2450can regulate the movement of the jack250. Furthermore, the movable range of the repetition lever240is determined to a predetermined range by disposing the protrusion2510and the protrusion receiving portion2450at the intersecting portion CP of the jack250and the repetition lever240. In other words, an up and down range of the protrusion receiving portion2450can regulate the movement of the repetition lever. Furthermore, the rotation range of the jack250can be simply and accurately determined when assembling the jack250to the repetition lever240by disposing the protrusion2510and the protrusion receiving portion2450at the intersecting portion CP of the jack250and the repetition lever240.

The position (hereinafter sometimes referred to as initial position) of the repetition lever240when the key110is at the rest position is as shown inFIG. 5A. As described above, the repetition lever240is rotatably connected with respect to the support210by the flexible portion220, and is applied with a force to rotate in a direction opposite a direction AS1by the first arm2802. At this time, the protrusion2510is located at a contacting position2451of the protrusion receiving portion2450.

At the time of key pressing, the coupling portion2443is pressed down with the small jack2504by the regulating button360, and the repetition lever240is subjected to the rotational force in the direction AS1. As shown inFIG. 5B, the protrusion2510is brought into contact with the protrusion receiving portion2450at a contacting position2453. As a result, the repetition lever240cannot rotate in the direction AS1. In other words, one side of the rotation range of the repetition lever240is regulated by the contacting position2453of the protrusion2510and the protrusion receiving portion2450. That is, as the protrusion2510regulates the movable range of the protrusion receiving portion2450, the movable range of the repetition lever240at the time of key pressing is limited.

Furthermore, at the time of key releasing, the repetition lever240is subjected to a rotational force in a direction opposite the direction AS1by the first arm2802. As shown inFIG. 5A, the protrusion2510is brought into contact with the protrusion receiving portion2450at the contacting position2451. As a result, the repetition lever240cannot rotate in the direction opposite the direction AS1. In other words, the other side of the rotation range of the repetition lever240is regulated by the contacting position2451of the protrusion2510and the protrusion receiving portion2450. That is, the movable range of the repetition lever240at the time of key releasing is regulated by the range of the protrusion receiving portion2450in which the protrusion2510moves. Thus, the repetition lever240can be prevented from being returned in excess at the time of key releasing.

In the present embodiment, the movable range of the repetition lever240is determined to the predetermined range by disposing the protrusion2510and the protrusion receiving portion2450at the intersecting portion CP of the jack250and the repetition lever240. In other words, the up and down range of the protrusion receiving portion2450can regulate the movement in an up and down direction of the repetition lever. Therefore, the rotation range of the repetition lever240at the time of key pressing and key releasing can be easily and accurately determined by disposing the protrusion2510and the protrusion receiving portion2450at the intersecting portion CP of the jack250and the repetition lever240.

Next, the rotation of the jack250will be described. The position (hereinafter sometimes referred to as initial position) of the jack250when the key110is at the rest position is as shown inFIG. 5A. As described above, the jack250is rotatably connected with respect to the jack support portion2105, and is applied with a force to rotate in a direction opposite the direction AS1by the second arm2804. At this time, the protrusion2510is located at the contacting position2451of the protrusion receiving portion2450.

At the time of key pressing, the small jack2504is pressed down by the regulating button360, and the jack250is subjected to the rotational force in the direction AS1(seeFIG. 6). As shown inFIG. 5B, the protrusion2510is brought into contact with the protrusion receiving portion2450at the contacting position2453. As a result, the jack250cannot rotate in the direction AS1. In other words, one side of the rotation range of the jack250is regulated by the contacting position2453of the protrusion2510and the protrusion receiving portion2450. That is, the movable range of the jack250at the time of key pressing is regulated by the range of the protrusion receiving portion2450in which the protrusion2510moves.

Furthermore, at the time of key releasing, the jack250is subjected to a rotational force in a direction opposite the direction AS1by the second arm2804. As shown inFIG. 5A, the protrusion2510is brought into contact with the protrusion receiving portion2450at the contacting position2451. As a result, the jack250cannot rotate in the direction opposite the direction AS1. In other words, the other side of the rotation range of the jack250is regulated by the contacting position2451of the protrusion2510and the protrusion receiving portion2450. That is, the movable range of the jack250at the time of key releasing is regulated by the range of the protrusion receiving portion2450in which the protrusion2510moves. Thus, the jack250can be prevented from being returned in excess at the time of key releasing.

In the present embodiment, the movable range of the jack250is determined to the predetermined range by disposing the protrusion2510and the protrusion receiving portion2450at the intersecting portion CP of the jack250and the repetition lever240. In other words, the range in a direction from the deeper side toward the forward side of the player of the protrusion receiving portion2450can regulate the movement of the jack250. Furthermore, the position of the jack250can be easily and accurately determined with respect to the direction from the deeper side toward the forward side of the player when assembling the jack250to the repetition lever240by disposing the protrusion2510and the protrusion receiving portion2450at the intersecting portion CP of the jack250and the repetition lever240.

InFIGS. 5A and 5B, an example in which the protrusion2510is disposed on the jack250, and the protrusion receiving portion2450is disposed on the repetition lever240has been shown, but the present invention is not limited thereto. The protrusion may be disposed on the repetition lever and the protrusion receiving portion may be disposed on the jack. However, when disposing the protrusion receiving portion on the jack, the large jack2502tends to become large and heavy, thus affecting the strength and the touch feeling (weight) of the jack. Thus, the design is restricted if the protrusion receiving portion is provided on the jack. Therefore, in the present embodiment, it is preferable to dispose the protrusion2510on the jack250and dispose the protrusion receiving portion2450on the repetition lever240. This can guarantee the strength of the jack and the touch feeling (weight). Furthermore, the movable range of the jack at the time of assembly can be increased and the operability can be enhanced by disposing the protrusion receiving portion2450on the repetition lever240.

Furthermore, in one embodiment of the present invention, a contacting surface at the contacting position2451and the contacting position2453of the protrusion receiving portion2450to be brought into contact with the protrusion2510is preferably made from a soft material. The impact at the time of contact is absorbed when the protrusion2510is brought into contact with the contacting surface made from a soft material. Noise at the time of contact between the protrusion2510and the protrusion receiving portion2450thus can be further reduced. Note that in the present embodiment, similar effects can be obtained even if the surface of the protrusion2510is made from a soft material.

In the conventional support assembly, a felt needed to be attached to a contact portion with respect to the jack in the repetition lever to absorb impact and reduce noise at the time of contact between the jack and the repetition lever. However, since an attaching position of the felt is an opening inner surface of the repetition lever, the attaching task becomes cumbersome. Furthermore, although the felt is a member that needs to be replaced by temporal degradation, and the like, the replacement task is cumbersome due to the problem of the attaching position of the felt. In the present invention, on the other hand, the attaching task of the felt to the repetition lever as in the prior art is not involved as the contacting surface of the protrusion receiving portion2450to be brought into contact with the protrusion2510is made from a soft material.

[Operation of Support Assembly20]

Next, the movement of the support assembly20is described when the key110is pressed down from the rest position (FIG. 1) to the end position.

FIG. 6is a side view for describing movement of the support assembly in the first embodiment of the present invention. When the key110is pressed down to the end position, the capstan screw120pushes up the support heel212to rotate the support210, with the axis of the through hole2109taken as a rotation center. When the support210rotates to move upward, the large jack2502pushes up the hammer roller315to cause the hammer shank310to collide with the hammer stopper410. Note that this collision corresponds to string hammering by a hammer in a general grand piano.

Immediately before this collision, while upward movement of the small jack2504is regulated by the regulating button360, the support210(jack support portion2105) further ascends. Therefore, the large jack2502rotates so as to go off from the hammer roller315. Here, by the regulating button360, upward movement of the coupling portion2443is also regulated. In this case, the small jack2504rotates to make contact with the vicinity of a connecting portion with the support210of the jack support portion2105. In the present invention, the movable range of the repetition lever240is limited and the rotation range of the jack250is determined to the predetermined range by disposing the protrusion2510and the protrusion receiving portion2450at the intersecting portion CP of the jack250and the repetition lever240. In this example, the regulating button360has also a function of a repetition regulating screw in the action mechanism in a general grand piano.

This regulates upward movement of the repetition lever240, which rotates so as to approach the support210. With these operations, a double escapement mechanism is achieved.FIG. 6is a drawing depicting this state. Note that, when the key110is being returned to the rest position, the hammer roller315is supported by the repetition lever240, and the large jack2502is returned below the hammer roller315. A rotational force to cause the large jack2502to be returned below the hammer roller315is provided by the second arm2804.

The double escapement is thus realized in an easier configuration compared to the support assembly used in a general grand piano, and the manufacturing cost can be reduced while suppressing the influence on the touch feeling.

[Sound Emission Mechanism of Keyboard Apparatus1]

As described above, the keyboard apparatus1is an example of application to an electronic piano. The operation of the key110is measured by the sensor510, and a sound in accordance with the measurement result is outputted.

FIG. 7is a block diagram depicting the structure of a sound emission mechanism of the keyboard apparatus according to the first embodiment of the present invention. A sound emission mechanism50of the keyboard apparatus1includes the sensors510(sensors510-1,510-2, . . .510-88for the eighty-eight keys110), a signal converting unit550, a sound source unit560, and an output unit570. The signal converting unit550obtains an electric signal outputted from the sensor510, and generates and outputs an operation signal in accordance with an operating state in each key110. In this example, the operation signal is a MIDI-format signal. Therefore, in accordance with the timing when the hammer shank310collides with the hammer stopper410by key-pressing operation, the signal converting unit550outputs Note ON. Here, a key number indicating which of the eighty-eight keys110has been operated and velocity for a speed immediately before the collision are also outputted in association with Note ON. On the other hand, when key-releasing operation is performed, in accordance with the timing when string vibrations are stopped by a damper in the case of a grand piano, the signal converting unit550outputs the key number and Note OFF in association with each other. To the signal converting unit550, a signal for another operation such as one on a pedal may be inputted and reflected to the operation signal. The sound source unit560generates a sound signal based on the operation signal outputted from the signal converting unit550. The output unit570is a loudspeaker or terminal which outputs the sound signal generated by the sound source unit560.

Second Embodiment

In the first embodiment, an example of defining the movable range of the protrusion2510by disposing a substantially trapezoidal protrusion receiving portion2450has been described, and now, in a second embodiment, an example of disposing a groove as the protrusion receiving portion will be described. A protrusion receiving portion2450A according to the second embodiment will be described for an example of disposing the protrusion receiving portion2450A of a C-shape having three sides.

FIGS. 8A and 8Bare side views depicting a structure of a support assembly20A according to the second embodiment of the present invention.FIG. 8Ais a side view of the support assembly20A when the key110is at the rest position.FIG. 8Bis a side view of the support assembly20A at the time of key pressing. In the support assembly20A, the jack250is rotatably supported by the support210, and a repetition lever240A is rotatably supported with respect to the support210. The protrusion2510is disposed at the intersecting portion CP of the jack250and the repetition lever240A. The protrusion receiving portion2450A for receiving the protrusion2510is also disposed at the intersecting portion CP. InFIGS. 8A and 8B, the protrusion2510is disposed on the large jack2502located at the intersecting portion CP, and the protrusion receiving portion2450A is disposed on an extension portion244A connected by being extended from the repetition lever240A located at the intersecting portion CP. The protrusion receiving portion2450A defines a movable range of the protrusion2510. Thus, the rotation range of the jack250is limited by the protrusion receiving portion2450A.

In the present embodiment, the rotation range of the jack250is determined to a predetermined range by disposing the protrusion2510and the protrusion receiving portion2450A at the intersecting portion CP of the jack250and the repetition lever240A. In the present embodiment, a side for receiving the protrusion2510is not arranged at the position on the player's forward side in the protrusion receiving portion2450A. However, as shown inFIG. 8B, the protrusion2510is brought into contact with the upper side of the protrusion receiving portion2450A by the rotation of the jack250and the repetition lever240A. The range in a direction from the deeper side toward the forward side of the player of the protrusion receiving portion2450A thus can regulate the movement of the jack250. Furthermore, the movable range of the repetition lever240A is determined to a predetermined range by disposing the protrusion2510and the protrusion receiving portion2450A at the intersecting portion CP of the jack250and the repetition lever240A. In other words, an up and down range of the protrusion receiving portion2450A can regulate the movement of the repetition lever. Furthermore, the rotation range of the jack250can be simply and accurately determined when assembling the jack250to the repetition lever240A by disposing the protrusion2510and the protrusion receiving portion2450A at the intersecting portion CP of the jack250and the repetition lever240A.

Third Embodiment

In a third embodiment, an example of disposing a protrusion receiving portion2450B having an n shape without one side on a lower side and having three sides will be described. In other words, the protrusion receiving portion2450B according to the third embodiment has an opening on a downward side.

FIGS. 9A and 9Bare side views depicting a structure of a support assembly20B according to the third embodiment of the present invention.FIG. 9Ais a side view of the support assembly20B when the key110is at the rest position, andFIG. 9Bis a side view of the support assembly20B at the time of key pressing. In the support assembly20B, the jack250is rotatably supported by the support210, and a repetition lever240B is rotatably supported with respect to the support210. The protrusion2510is disposed at the intersecting portion CP of the jack250and the repetition lever240B. The protrusion receiving portion2450B for receiving the protrusion2510is also disposed at the intersecting portion CP. InFIGS. 9A and 9B, the protrusion2510is disposed on the large jack2502located at the intersecting portion CP, and the protrusion receiving portion2450B is disposed on an extension portion244B connected by being extended from the repetition lever240B located at the intersecting portion CP. The protrusion receiving portion2450B defines a movable range of the protrusion2510. Thus, the rotation range of the jack250is limited by the protrusion receiving portion2450B.

In the present embodiment, the rotation range of the jack250is determined to a predetermined range by disposing the protrusion2510and the protrusion receiving portion2450B at the intersecting portion CP of the jack250and the repetition lever240B. In the present embodiment, a side for receiving the protrusion2510is not arranged at the position on the lower side of the repetition lever240B in the protrusion receiving portion2450B. However, as shown inFIG. 9B, the protrusion2510is brought into contact with the upper side of the protrusion receiving portion2450B by the rotation of the jack250and the repetition lever240B. The range in a direction from the deeper side toward the forward side of the player of the protrusion receiving portion2450B thus can regulate the movement of the jack250. Furthermore, when the jack250and the repetition lever240B are rotated in a direction opposite the direction AS1at the time of key releasing, the jack250can be prevented from being returned in excess by the side on the player's deeper side of the protrusion receiving portion2450B.

Furthermore, the movable range of the repetition lever240B is determined to a predetermined range by disposing the protrusion2510and the protrusion receiving portion2450B at the intersecting portion CP of the jack250and the repetition lever240B. In other words, an up and down range of the protrusion receiving portion2450B can regulate the movement of the repetition lever. Furthermore, the rotation range of the jack250can be simply and accurately determined when assembling the jack250to the repetition lever240B, by disposing the protrusion2510and the protrusion receiving portion2450B at the intersecting portion CP of the jack250and the repetition lever240B.

In each embodiment described above, an electronic piano is described as an example of a keyboard apparatus to which a support assembly is applied. On the other hand, the support assembly of the above-described embodiments can be applied to a grand piano (acoustic piano). In this case, the sound emission mechanism corresponds to a hammer and a string. The string generates a sound by being struck by a hammer in accordance with the key pressing operation.

According to one embodiment of the present invention, the manufacturing cost of the support assembly can be reduced while decreasing a change in touch feeling at the time of key operation, compared with a keyboard apparatus of an acoustic piano.