Keyboard device for keyboard instrument

Abstract

A keyboard device for a keyboard instrument, which is capable of obtaining an excellent tactile sensation when a key is pressed down, and in turn is capable of improving responsiveness when a key that has been pressed down performs a pivoting return movement to its original position, and thereby obtaining appropriate string striking repeatability. The keyboard device comprises a keyboard base; the keys are arranged on the keyboard base; and a key support mechanism that, when the key is pressed, causes the pressed key to operate such that the key pivotally moves around a virtual fulcrum located rearward of the rear end of the key. The key support mechanism includes: a first arm swingably engaged with the first pivot shaft; and a second arm swingably engaged with the second pivot shaft. The second arm is provided with a second arm weight made of a material having a greater specific gravity than the second arm.

Description

Technical Field

[0001] The present invention relates to a keyboard device for a keyboard musical instrument, which is suitable for a keyboard musical instrument such as an electronic piano and in which a depressed one of the keys operates so that it moves pivotally around a virtual fulcrum located behind the rear end of the key. Background Art

[0002] Conventionally, as a keyboard device of this type, there is known a keyboard device disclosed in, for example, Japanese Laid-Open Patent Gazette (Publication) No. 2023-50758 which has been filed by the present applicant. The keyboard device includes: a keyboard base; a key, which is arranged on the keyboard base; and a key support mechanism, which engages with the keyboard base and supports the key from below. The key support mechanism includes a first arm and a second arm extending in the front-to-back direction. The first arm and the second arm are pivotally supported on a first pivot shaft and a second pivot shaft, respectively. Furthermore, the first arm has its front end pivotally and slidably connected to a front portion of the key, while the second arm has its front end pivotally and slidably connected to a predetermined portion of the first arm, and has its rear end pivotally connected to the rear end of the key.

[0003] In the keyboard device constructed as described above, when the front end of the key is pressed downward by key pressing, the first arm pivotally moves around the first pivot axis so that the front end of the first arm moves downward, and the weight provided on the rear end of the first arm moves upward, and the second arm pivotally moves around the second pivot axis so that the front end of the second arm moves upward, and the rear end of the second arm moves downward. Thus, the key pivotally moves around the virtual fulcrum located behind the rear end thereof so that the front end of the key moves downward.

[0004] Then, when the player's finger is released from the key that has been pressed and the key is released, the first arm and the second arm cause the key to perform a pivotal return movement to its original position while pivotally moving in a direction opposite to the above-described direction of the pivotal movement of the first arm and the second arm. Specifically, the first arm pushes up the front end of the key by pivotally moving, so that the weight on the rear end of the first arm that has moved upward moves downward, and the front end of the first arm moves upward. Furthermore, the second arm promotes the pivotal movement of the first arm by the downward movement of the front end of the second arm, and pushes up the rear end of the key by the upward movement of the rear end of the second arm. Thus, the key (whose front end pivotally moves upward around the virtual fulcrum mentioned above) performs a pivotal return movement to its original position.

[0005] In the keyboard device described above, the weight of the first arm is increased by providing a weight on the first arm, thereby obtaining a satisfactorily responsive tactile feel during key pressing, and, during key release, the first arm is pivotally moved to thereby push up the key and cause the key to perform a pivotal return movement to its original position. Furthermore, as the weight of the first arm gradually increases, the response to the key pressing increases, thereby further improving the tactile feel. However, when the moment of inertia of the first arm is increased by increasing the weight of the first arm, the first arm becomes difficult to pivotally move. As a result, when the pressed key performs a pivotal return movement to its original position, the responsiveness of the key is reduced, which sometimes makes it impossible to obtain appropriate string striking repeatability of the key. Therefore, the keyboard device has room for improvement. Summary of the invention

[0006] An object of the present invention is to provide a keyboard device for a keyboard musical instrument, which is capable of obtaining an excellent touch when performing key depression, and further capable of achieving improved responsiveness when the depressed key performs a pivotal return movement to its original position, thereby making it possible to obtain appropriate string-strike repeatability.

[0007] In order to achieve the above object, the present invention provides a keyboard device for a keyboard musical instrument, comprising: a keyboard base; a key, which extends a predetermined length in the front-to-back direction and is arranged on the keyboard base; and a key supporting mechanism, which is engaged with the keyboard base and is arranged to support the key from below, and when the key is pressed, the key supporting mechanism causes the pressed key to operate, so that the key pivotally moves around a virtual fulcrum located behind the rear end of the key, wherein the key supporting mechanism comprises: a first arm, which is configured to extend a predetermined length in the front-to-back direction and is swingably engaged with a first pivot axis arranged on the keyboard base, and the first arm causes the front end of the key to be moved. The keyboard key has an end pivotally and slidably connected to the front part of the key; and a second arm, which is configured to extend a predetermined length in the front-to-back direction and is swingably engaged with a second pivot axis provided on the keyboard base at a position rearward of the first pivot axis, the second arm has its rear end pivotally connected to the rear part of the key, and includes a second arm front side connecting part, which is arranged in front of the second pivot axis and is pivotally and slidably connected to the first arm rear side connecting part rearward of the first pivot axis of the first arm, and wherein the second arm is provided with a second arm weight made of a material having a greater specific gravity than the second arm.

[0008] According to this configuration, a key extending a predetermined length in the front-to-rear direction and arranged on the keyboard base is supported from below by a key support mechanism having the first arm and the second arm described above, and, when pressed, the key operation is caused so that the key pivotally moves around a virtual fulcrum located behind the rear end of the key. Since the second arm described above is provided with a second arm weight made of a material having a greater specific gravity than the second arm, the moment of inertia of the second arm is increased by increasing the weight of the second arm. This makes it possible to provide a sufficient response when performing key pressing, thereby obtaining an excellent touch during key pressing. Furthermore, an excellent touch can be obtained by increasing the weight of the second arm, thereby suppressing the increase in the weight of the first arm. Thus, compared with the case in which only the weight of the first arm is increased, the responsiveness of the key that has been pressed when the key performs a pivotal return movement to its original position can be improved, thereby obtaining appropriate string striking repeatability of the key.

[0009] Preferably, the second arm weight is arranged in front of the second pivot axis and / or around the second pivot axis.

[0010] According to the construction of this preferred embodiment, since the second arm weight is arranged in front of the second pivot axis engaged with the second arm and / or around the second pivot axis, the weight of the second arm can be increased relatively easily. In particular, in the case where the second arm weight is arranged in front of the second pivot axis, the second arm becomes easy to pivotally move in a direction in which the front end of the second arm, which has moved upward when the key is pressed, moves downward according to the release of the key. As a result, the first arm (whose front end has been pressed by the pressing of the key) is further promoted to perform a pivotal return movement to its original position. According to the above, the touch and responsiveness of the key when the key is pressed can be further improved.

[0011] Preferably, the second arm weight is mounted on at least one of the left and right sides of the second arm.

[0012] According to the construction of this preferred embodiment, since the second arm weight is installed on at least one of the left and right sides of the second arm, no trouble will be caused in the operation of the second arm during key pressing, and, further, the second arm can be adjusted to the desired weight by installing the second arm weight in the second arm.

[0013] Preferably, the second arm includes a weight accommodating portion extending through the second arm in the left-right direction, and the second arm weight is installed in the second arm in a state of being accommodated in the weight accommodating portion by being inserted into the weight accommodating portion from the outside.

[0014] According to the construction of this preferred embodiment, when the second arm weight is installed in the second arm, the second arm weight can be easily installed in the second arm only by inserting the second arm weight into the weight accommodating portion from the outside.

[0015] More preferably, the second arm weight is accommodated in the weight accommodating portion in a state in which the exterior of the second arm weight is covered with a predetermined synthetic resin.

[0016] According to the configuration of this preferred embodiment, in a state in which the exterior of the second arm weight is covered with synthetic resin, the second arm weight is accommodated in the weight accommodation portion of the second arm, and therefore, during the operation of the second arm in accordance with key pressing, the second arm weight is prevented from rattling or vibrating in the weight accommodation portion. This makes it possible to prevent the second arm weight from generating noise during the operation of the second arm.

[0017] Preferably, the second arm is manufactured by molding a synthetic resin, and, when the second arm is molded, the second arm is integrally formed with the second arm weight.

[0018] According to the construction of this preferred embodiment, since the second arm manufactured by molding synthetic resin is integrally formed with the second arm weight when molding the second arm, there is no need to install the second arm weight in the second arm later, and the step of installing the second arm weight during the manufacturing of the second arm can be omitted, which makes it relatively easy to manufacture the second arm provided with the second arm weight.

[0019] The above objects, features and advantages and other objects, features and advantages of the present invention will become more apparent from the following detailed description taken in conjunction with the accompanying drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] Figure 1A and Figure 1B is a perspective view of a portion (one octave section) of a keyboard device for an electronic piano to which the present invention is applicable, wherein: Figure 1A shows the appearance of a keyboard device, and Figure 1B shows a state in which keys other than white keys and black keys at the left end of the keyboard device are omitted;

[0021] Figure 2 The white keys and the black keys are in a state where they are removed from the keyboard base together with the corresponding key supporting mechanisms for the white keys and the black keys. Figure 1B A perspective view of a keyboard device shown in FIG.

[0022] Figure 3A is a plan view of the keyboard device from which keys other than white keys and black keys at the left end of the keyboard device are omitted, and, Figure 3B It is along Figure 3A A cross-sectional view taken along line AA;

[0023] Figure 4A and Figure 4B is a perspective view of white keys and key support mechanisms for the white keys, wherein Figure 4Ashows the white keys and key support mechanism in a connected state, and, Figure 4B showing the white keys and key support mechanism in a disassembled state;

[0024] Figure 5A and Figure 5B is a perspective view of a black key and a key supporting mechanism for the black key, wherein Figure 5A The black keys and key support mechanism are shown in a connected state, and Figure 5B showing the black keys and key support mechanism in a disassembled state;

[0025] Fig. 6A and Figure 6B is a view useful in explaining the operation of the white keys in a keyboard device, wherein Fig. 6A shows the key release state, and, Figure 6B Shows the key pressed state;

[0026] Fig. 7A and Figure 7B is a view useful in explaining the operation of the black keys in a keyboard device, wherein Fig. 7A shows the key release state, and, Figure 7B Shows the key pressed state;

[0027] FIG. 8A to FIG. 8C is a view of a second arm according to a first embodiment of the present invention, wherein Fig. 8A It is a perspective view. Figure 8B is a side view, and Figure 8C is an exploded perspective view showing a state in which the second arm weight is removed from the second arm;

[0028] 9A to 9C is a view of a second arm according to a second embodiment of the present invention, wherein Fig. 9A It is a perspective view. Fig. 9B is a side view, and Fig. 9C is an exploded perspective view showing a state in which the second arm weight is removed from the second arm;

[0029] FIG. 10A to FIG. 10C is a view of a second arm according to a third embodiment of the present invention, wherein Fig. 10A It is a perspective view. Fig. 10B is a side view, and Fig. 10C is an exploded perspective view showing a state in which the second arm weight is removed from the second arm;

[0030] FIG. 11A to FIG. 11C is a view of a second arm according to a fourth embodiment of the present invention, wherein Fig.11A It is a perspective view. Fig. 11B is an exploded perspective view showing a state in which the second arm weight is removed from the second arm, and, Fig. 11Cis a perspective view showing a state in which the second arm weight is separated into a weight main body and a weight cover; and

[0031] Fig. 12A and Fig. 12B is a view of a second arm according to a fifth embodiment of the present invention, wherein Fig. 12A is a perspective view, and Fig. 12B It is a side view. DETAILED DESCRIPTION

[0032] The present invention will now be described in detail with reference to the accompanying drawings in which preferred embodiments of the invention are shown. Figure 1A Only one octave section of the keyboard device 1 for the electronic piano to which the present invention is applied is shown. Note that, hereinafter, a description will be given first of the basic configuration of the keyboard device 1 and its operation, and then a description of the essential part of the present invention will be given.

[0033] Figure 1B Show Figure 1A 1 is a state of the keyboard device 1 shown in , in which the keys 2 except the white keys 2 a and the black keys 2 b at the left end of the keyboard device 1 are omitted. Figure 2 Show Figure 1B , in which the white keys 2 a and the black keys 2 b are removed from the keyboard base 4 together with the corresponding key support mechanisms 6 for the white keys 2 a and the black keys 2 b.

[0034] The keyboard device 1 is composed of: a keyboard base 4; a plurality of keys 2, which include white keys 2a and black keys 2b and are arranged side by side in the left-right direction; a key supporting mechanism 6, each of which is pivotally mounted on the keyboard base 4 for each key to support an associated one of the keys 2 from below; and a key switch 3, each of which is used to detect key depression information of an associated one of the keys 2.

[0035] The keyboard base 4 includes a base body 4a formed as a resin molded product, which is made by, for example, injection molding a predetermined resin material (eg, ABS resin) into a predetermined shape. Figure 3A and Figure 3B As shown in FIG. 1 , the base body 4a has a front portion 11, a middle portion 12, and a rear portion 13, each of which is integrally formed along the left-right direction (along the Figure 3AThe front portion 11, the middle portion 12, and the rear portion 13 are formed integrally with each other via a plurality of ribs 14, which are provided with certain intervals therebetween in the left-right direction and each extend in the front-rear direction. Note that in the following description, the front portion 11, the middle portion 12, and the rear portion 13 of the base body 4a of the keyboard base 4 will be referred to as "base front portion 11", "base middle portion 12", and "base rear portion 13", respectively.

[0036] The base front portion 11 is mainly used to guide the white key 2a during the depression of the white key 2a and limit the upper limit position and the lower limit position of the front end of the white key 2a. On the base front portion 11, a plurality of white key guides 11a are erected, each of which is inserted into each associated white key 2a in the white key 2a from below, so as to prevent the white key 2a from swinging laterally in a state of being arranged side by side in the left-right direction. Furthermore, the base front portion 11 has an engagement hole 11b and an engagement hole 11b extending vertically through the base front portion 11, and the engagement hole 11b and the engagement hole 11b are respectively formed on the left and right sides of each of the white key guides 11a. The paired left upper limit position regulating portion 21 and the right upper limit position regulating portion 21 of the white key 2a mentioned below are engaged with the corresponding engagement hole 11b and the engagement hole 11b in a state of being inserted through the corresponding engagement hole 11b and the engagement hole 11b. Furthermore, the base front portion 11 has its front end formed with a stopper mounting portion 11c, which protrudes forward and extends in the left-right direction along the entirety of the base body 4a. The key upper limit stopper 16a and the key lower limit stopper 16b for the white key 2a are mounted on the lower surface and the upper surface of the stopper mounting portion 11c, respectively, so that the key upper limit stopper 16a and the key lower limit stopper 16b extend in the left-right direction. Note that the stopper mounting portion 11d for the black key extending in the left-right direction along the entirety of the base body 4a is provided at a predetermined position of the base front portion 11 behind each white key guide 11a, and the key upper limit stopper 17 for the black key is mounted on the stopper mounting portion 11d so that the key upper limit stopper 17 extends in the left-right direction.

[0037] The base middle portion 12 is mainly used to guide the black key 2b during depression of the black key 2b and swingably supports the first arm 31 and the second arm 32 described below of each of the key support mechanism 6a associated with the white key and the key support mechanism 6b associated with the black key. The base middle portion 12 has: a flat portion 12a in the form of a flat plate extending in the left-right direction; and a plurality of black key guides 12b erected on the flat portion 12a with appropriate intervals provided therebetween in the left-right direction. Each black key guide 12b is inserted into an associated one of the black keys 2b from below to prevent lateral swinging of the black key 2b. Further, the base middle portion 12 has its front portion provided with a first arm support portion 18 for supporting the first arm 31 of the key support mechanism 6. The first arm support portion 18 has a plurality of first pivot shafts 18a, each of which is provided between the rib 14 and each adjacent two of the ribs 14 so that the first pivot shafts 18a extend in the left-right direction. The first arm 31 is swingably supported on the associated first pivot shaft 18a among the first pivot shafts 18a. In addition, the base middle part 12 has its rear portion provided with a second arm support portion 19 for supporting the second arm 32 of the key support mechanism 6. The second arm support portion 19 has a plurality of second pivot shafts 19a, each of which is provided between the rib 14 and each adjacent two of the ribs 14, so that the second pivot shaft 19a extends in the left-right direction. The plurality of second pivot shafts 19a are arranged on the same axis extending in the left-right direction at a position higher than the first pivot shaft 18a behind the first pivot shaft 18a, and the second arm 32 is swingably supported on the associated second pivot shaft 19a among the second pivot shafts 19a. Note that the first arm lower limit stopper 10b extending in the left-right direction along the entirety of the base body 4a is provided at a predetermined position of the intermediate stop 8 mentioned below provided below the base middle part 12.

[0038] Furthermore, the above-mentioned key switch 3 is provided on the lower portion of the keyboard base 4 between the above-described base front portion 11 and the base middle portion 12. The key switch 3 is formed of: a laterally elongated printed circuit board 3a extending in the left-right direction; and a plurality of switch bodies 3b formed of rubber switches attached to the printed circuit board 3a on a key-by-key basis for being pressed by an associated one of the first arms 31 when a key is pressed.

[0039] The base rear portion 13 is mainly used to guide the key 2 in the vertical direction through the rear end of the key 2, while preventing the key 2 from swinging laterally, and to limit the upper limit position of the rear end of the associated first arm 31 in the first arm 31. Figure 2 and Figure 3AAs shown in , the rear portion 13 of the base has a plurality of partition walls 13a formed with predetermined intervals therebetween in the left-right direction so as to separate each adjacent two of the keys 2 from each other. Figure 3B As shown in the figure, the first arm upper limit stopper 10a extending in the left-right direction along the entirety of the base body 4a is provided at a predetermined position of the upper portion of the base rear portion 13. The first arm upper limit stopper 10a and the first arm lower limit stopper 10b provided on the base middle portion 12 are used to limit the upper limit position and the lower limit position of the first arm 31, respectively, when the first arm 31 having a function as a hammer for adding a touch weight to the key 2 is pivotally moved upward and downward. In addition, a metal cover plate 15 extending in the left-right direction along the entirety of the base body 4a and provided to cover the rear end of the key 2 is mounted on the upper portion of the base rear portion 13.

[0040] like Figure 2 and Figure 3A As shown in FIG. 1 , the base body 4a of the keyboard base 4 constructed as described above is formed with a plurality of first openings 5a opened upward and forward and a plurality of second openings 5b opened upward. The first arms 31 of the key support mechanism 6 are respectively engaged with the associated first pivot shafts 18a of the first pivot shafts 18a from the outside via the above-mentioned first openings 5a. Furthermore, the second arms 32 are respectively engaged with the associated second pivot shafts 19a of the second pivot shafts 19a from the outside via the above-mentioned second openings 5b.

[0041] Furthermore, in the keyboard base 4 described above, a plurality of base bodies 4a are connected to each other in a state of being arranged side by side in the left-right direction, and each is screwed to the front rail 7, the middle rail 8, and the rear rail 9 in a state of being placed on the front rail 7, the middle rail 8, and the rear rail 9, each of which is made of metal and extends in the left-right direction and is arranged with a predetermined interval therebetween in the front-back direction. The keyboard base 4 is fixed to a key bed, not shown, of an electronic piano via the front rail 7 and the rear rail 9.

[0042] Next, the key 2 and the key supporting mechanism 6 will be described. Figure 4A The white keys 2a and the key supporting mechanisms 6a for the white keys 2a are shown in an enlarged scale, and Figure 4B The white keys 2a and the key support mechanisms 6a for the white keys 2a are shown in a disassembled state. Figure 4A and Figure 4BAs shown in , the white key 2a is formed, for example, by injection molding a predetermined resin material (e.g., AS resin) into a hollow shape extending a predetermined length in the front-to-rear direction and open downward. The white key 2a has its front end formed with a pair of left upper limit position regulating parts 21 and right upper limit position regulating parts 21, which protrude downward from the corresponding side walls of the front end of the white key 2a and each have its lower end bent forward. As described above, the left upper limit position regulating part 21 and the right upper limit position regulating part 21 are engaged with the corresponding left engagement holes 11b and right engagement holes 11b of the base front part 11 in a state of being inserted through them.

[0043] Furthermore, at a predetermined position of the front portion of the white key 2a, behind the upper limit position adjusting portion 21, a key front side connecting portion 22 connected to the first arm 31 of the key supporting mechanism 6a is formed. The key front side connecting portion 22 includes a connecting recess 22a formed in a U shape having a narrow groove shape in a side view and open to the front. Furthermore, the connecting recess 22a has a buffer component 20 attached to the connecting recess 22a, and the buffer component 20 is formed to cover the entire inner peripheral surface of the connecting recess 22a, so as to suppress the generation of noise when the connecting shaft 35b mentioned below of the first arm 31 slides in the inner peripheral surface of the connecting recess 22a. Note that in the front portion of the white key 2a, between the upper limit position adjusting portion 21 mentioned above and the key front side connecting portion 22, a key weight 30 (see FIG. 2 ) for adding a desired touch weight to the white key 2a during the pressing of the white key 2a is installed. Figure 3B ).

[0044] Furthermore, the white key 2a has its rear portion provided with a key rear side connection portion 23 connected to the second arm 32 of the key support mechanism 6a. The key rear side connection portion 23 has: a plate-shaped connection body portion 23a which hangs downward from the transverse center portion of the white key 2a and has a predetermined thickness in the left-right direction; and a pair of left and right engagement protrusions 23b and right engagement protrusions 23b which coaxially protrude from the left and right sides of the connection body portion 23a, respectively. Further, the rear portion of the white key 2a is formed with a tool insertion hole 24 which extends vertically through the rear portion and is used to insert a predetermined tool into the tool insertion hole 24 from above for disconnecting the white key 2a from the second arm 32 of the key support mechanism 6a, for example, when maintaining the keyboard device 1.

[0045] On the other hand, the key supporting mechanism 6a includes a first arm 31 and a second arm 32 which are engaged with each other and are respectively connected to the key front side connecting portions 22 and the key rear side connecting portions 23 of the white key 2a.

[0046] like Figure 4BAs shown in FIG. 1 , the first arm 31 is composed of an arm main body 33 and two weights 34 and the weights 34 attached to the arm main body 33. The arm main body 33 is formed as a resin molded product, which is made, for example, by injection molding a predetermined resin material (e.g., polyacetal resin) into a predetermined shape. The arm main body 33 extends a predetermined length in the front-to-back direction, and a first arm front-side connecting portion 35 connected to the key front-side connecting portion 22 of the white key 2a is formed at its front end. The first arm front-side connecting portion 35 includes: a box portion 35a having a box shape that is open upward and forward; and a connecting shaft 35b, which is arranged so that it extends in the left-to-right direction in a state where the front upper ends of the left and right side walls of the box portion 35a are connected to each other. The connecting shaft 35b is connected to the connecting recess 22a of the key front-side connecting portion 22 of the white key 2a so that the connecting shaft 35b can be pivotally moved and can slide in the front-to-back direction.

[0047] Furthermore, the arm main body 33 has a bearing portion 36 formed at a predetermined position immediately behind the first arm front side connection portion 35. The bearing portion 36 has an inverted U shape that is open downward in a side view, and is pivotally engaged with the first pivot shaft 18a of the keyboard base 4. Furthermore, the arm main body 33 has a first arm rear side connection portion 37 formed at a predetermined position behind the bearing portion 36 for connection to the second arm 32. Specifically, the first arm rear side connection portion 37 has a connection shaft 37a extending in the left-right direction, wherein respective opposite ends of the connection shaft 37a protrude outward from the left and right sides of the arm main body 33. The opposite ends of the connection shaft 37a are engaged with a connection recess 45b and a connection recess 45b of a second arm front side connection portion 45 mentioned below of the second arm 32.

[0048] The two weights 34 formed as elongated and narrow plates and the weights 34 are mounted on the weight mounting portion 38 in a state of sandwiching the weight mounting portion 38, which is the rear portion of the arm body 33. Note that each weight 34 is made of a material (metal, such as iron) having a larger specific gravity than the arm body 33, and is formed, for example, by stamping a metal plate into a predetermined shape.

[0049] The second arm 32 is formed into a resin molded product having a predetermined shape by injection molding of the same resin material as that of the arm body 33 of the first arm 31. The second arm 32 is shorter than the first arm 31 and extends a predetermined length in the front-rear direction. Furthermore, the second arm 32 has a bearing portion 41 having a C-shape opened forward in a side view near its longitudinal center. The bearing portion 41 is pivotally engaged with an associated one of the second pivot shafts 19a of the keyboard base 4.

[0050] Furthermore, the second arm 32 has its rear portion provided with a second arm rear side connecting portion 42 connected to the key rear side connecting portion 23 of the white key 2a. The second arm rear side connecting portion 42 is formed in a forked shape, and has two left connecting arm portions 43 and right connecting arm portions 43 extending in parallel with each other by a predetermined length along the longitudinal direction of the second arm 32. Each connecting arm portion 43 has its rear end formed with a connecting hole 43a extending through the connecting arm portion 43 in the left-right direction. The two connecting arm portions 43 and the connecting arm portion 43 sandwich the connecting body portion 23a of the key rear side connecting portion 23 of the white key 2a between their rear ends from the left and right, and each connecting hole 43a has an associated one of the engaging protrusions 23b of the key rear side connecting portion 23 pivotally fitted therein.

[0051] Furthermore, the second arm 32 has its front portion provided with a second arm front side connection portion 45 connected to the first arm rear side connection portion 37 of the first arm 31. The second arm front side connection portion 45 has a pair of left and right connection portions 45a and 45a arranged with a predetermined interval in the left-right direction. The connection portions 45a and 45a are each formed with a connection recess 45b having a U-shape having a slit-like shape in a side view and open forward. The left and right connection portions 45a and 45a of the second arm front side connection portion 45 are pivotally and slidably engaged with the respective opposite ends of the connection shaft 37a of the first arm 31 via the connection recesses 45b and 45b thereof.

[0052] Figure 5A The black key 2b and the key supporting mechanism 6b for the black key 2b are shown in an enlarged scale, and Figure 5B The black key 2b and the key support mechanism 6b are shown in a disassembled state. The black key 2b is formed, for example, by injection molding a resin material that is the same as the resin material of the white key 2a into a hollow shape that extends in the front-to-back direction by a predetermined length that is shorter than the predetermined length of the white key 2a and is open downward. The black key 2b has its front lower end provided with a key front side connecting portion 26 that is formed substantially the same as the key front side connecting portion 22 of the white key 2a. The key front side connecting portion 26 has a connecting recess 26a that is formed in a U shape that has a narrow groove shape in a side view and is open forward. Furthermore, the key front side connecting portion 26 has an extension portion 26b on the lower front end of the connecting recess 26a. The extension portion 26b extends a predetermined length in front of the front surface of the main body of the black key 2b. The extension portion 26b functions as an upper limit position regulating portion of the black key 2b. Note that in the following description, members of the black keys 2b and key supporting mechanisms 6b having the same configurations as those of the white keys 2a and key supporting mechanisms 6a described above are denoted by the same reference numerals, and detailed descriptions thereof will be omitted.

[0053] The key supporting mechanism 6b supporting the black key 2b is constructed substantially the same as the key supporting mechanism 6a associated with the white key described above. Specifically, the arm body 33 of the first arm 31 of the key supporting mechanism 6b and the second arm 32 thereof are constructed completely the same in shape and size as the arm body 33 and the second arm 32 of the key supporting mechanism 6a associated with the white key. Note that although Figure 5A and Figure 5B , the two left weights 34 and right weights 34 of the key supporting mechanism 6b for the black key 2b are illustrated exactly the same as the weights 34 and weights 34 of the key supporting mechanism 6a for the white key 2a, but the shapes and lengths of the weights 34 and weights 34 of the key supporting mechanism 6a and the key supporting mechanism 6b are changed as deemed appropriate depending on the touch weight required for the key 2, etc.

[0054] Next, a description will be given of the operations of the keys 2 and the key supporting mechanism 6 of the keyboard device 1 constructed as described above. Fig. 6A and Figure 6B It is a view useful in explaining the operation of the white keys 2a and the key support mechanisms 6a associated with the white keys 2a. Fig. 7A and Figure 7B It is a view useful in explaining the operation of the black key 2b and the key supporting mechanism 6b associated with the black key 2b.

[0055] When from Fig. 6A When the player presses the front end of the white key 2a with his / her finger from the key release state shown in FIG. 1 , the key front side connection portion 22 of the white key 2a moves downward, whereby the first arm 31 pivotally moves in the counterclockwise direction around the first pivot axis 18a. Further, in accordance with the pivotal movement of the first arm 31, the second arm front side connection portion 45 engaged with the connection axis 37a of the first arm 31 via the connection recess 45b and the connection recess 45b moves upward. Thereby, the second arm 32 pivotally moves in the clockwise direction around the second pivot axis 19a. Then, in accordance with this pivotal movement of the second arm 32, the key rear side connection portion 23 connected to the second arm 32 via the second arm rear side connection portion 42 formed at the rear end of the second arm 32 is pulled downward, whereby the rear end of the white key 2a moves downward.

[0056] Note that, during the above-mentioned pivotal movement of the first arm 31, the box portion 35a of the first arm front side connecting portion 35 moves downward, and therefore, the switch body 3b of one of the key switches 3 associated with the depressed key 2 is pressed from above by the bottom wall of the box portion 35a. As a result, in the electronic piano, key depression information of the depressed key 2 is detected, and based on the detected key depression information, a sound is produced from a speaker not shown.

[0057] As described above, in the case where the white key 2a is depressed, according to the counterclockwise pivotal movement of the first arm 31, as shown in FIG. Figure 6B , the weight 34 of the first arm 31 is tilted so that the weight 34 becomes higher as it extends rearward, whereby the rear end of the weight 34 contacts the first arm upper limit stopper 10a from below. This prevents further pivotal movement of the first arm 31. When the front end of the white key 2a is pressed to its lowest position, the front end of the white key 2a contacts the key lower limit stopper 16b, which prevents further pressing of the white key 2a.

[0058] The white key 2a pressed as above is operated so that the white key 2a is pivotally moved about the virtual fulcrum P located behind its rear end. For example, the position of the virtual fulcrum P is set so that the distance from the front end of the white key 2a is approximately as long as twice the length of the white key 2a itself. Thus, when the front end of the white key 2a is pressed to the lowest position, the white key 2a is at the same position as the white key 2a. Fig. 6A Compared with the case in the key release state shown in , the front end of the white key 2a is positioned at a lower predetermined key stroke (e.g., 10 mm), and the rear end of the white key 2a is positioned at a distance approximately half of the lower predetermined key stroke (e.g., 5 mm).

[0059] On the other hand, when the finger is released from the depressed white key 2a, the first arm 31 of the key support mechanism 6a is pivotally moved in the direction opposite to the above-mentioned direction by the own weight of the weight 34, and, accordingly, the second arm 32 is also pivotally moved in the direction opposite to the above-mentioned direction. According to this pivotal movement of the second arm 32, the white key 2a is pivotally moved upward around the virtual fulcrum P. Then, a predetermined portion of the first arm 31 at the rear of the first pivot axis 18a moves to contact the first arm lower limit stopper 10b from above, and both the upper limit position regulating portion 21 of the white key 2a and the upper limit position regulating portion 21 move to contact the key upper limit stopper 16a from below, thereby preventing further pivotal movement of the white key 2a, and the white key 2a returns to its original key release state.

[0060] Furthermore, when the black key 2b is depressed, the same operation as the above-described operation of the white key 2a and the key support mechanism 6a is performed. More specifically, when the black key 2b is depressed, the white key 2a and the key support mechanism 6a are operated. Fig. 7AWhen the front end of the black key 2b is pressed down from the key release state shown in the figure, the first arm 31 is pivotally moved in the counterclockwise direction around the first pivot axis 18a, and the second arm 32 is pivotally moved in the clockwise direction around the second pivot axis 19a. Thus, the black key 2b is operated so that the black key 2b is pivotally moved around the virtual fulcrum Q located behind its rear end. Note that, similarly to the above-mentioned virtual fulcrum P of the white key 2a, for example, the position of the virtual fulcrum Q is set so that the distance from the front end of the black key 2b is approximately twice the length of the black key 2b itself. Therefore, when the front end of the black key 2b is pressed down to its lowest position, the position of the black key 2b is approximately twice the length of the black key 2b itself. Fig. 7A Compared to the case in the key-release state shown in , the front end of the black key 2b is positioned at a lower predetermined keystroke, and the rear end of the black key 2b is positioned at a distance approximately half of the lower predetermined keystroke.

[0061] On the other hand, when the finger is released from the black key 2b that has been depressed, the first arm 31 and the second arm 32 of the key supporting mechanism 6b are pivotally moved in respective directions opposite to the above-mentioned directions, and, accordingly, the black key 2b is pivotally moved upward about the virtual fulcrum Q. Then, the extending portion 26b of the key front side connecting portion 26 of the black key 2b is moved to come into contact with the key upper limit stopper 17 from below, whereby further pivotal movement of the black key 2b is stopped, and the black key 2b returns to its original key-released state.

[0062] Next, refer to FIG. 8A to FIG. 8C arrive Fig. 12A and Fig. 12B The essential part of the present invention is that in the keyboard device 1, the second arm 32 of the key support mechanism 6 is provided with a second arm weight made of a material (metal such as iron) having a larger specific gravity than the second arm 32.

[0063] FIG. 8A to FIG. 8C A second arm 32A according to a first embodiment of the present invention is shown, wherein: Fig. 8A It is a perspective view. Figure 8B is a side view, and Figure 8C is an exploded perspective view. FIG. 8A to FIG. 8C As shown in the figure, the second arm 32A has two left second arm weights 52 and right second arm weights 52 installed in the connecting portion 51, and the connecting portion 51 is arranged so as to connect between the bearing portion 41 formed near the center of the second arm 32A and the second arm front side connecting portion 45 formed at the front end of the second arm 32A. The connecting portion 51 has a partition wall 51a formed at its center in the left-right direction, and, on the left and right sides of the partition wall 51a, there are two left weight mounting portions 51b and right weight mounting portions 51b (only one of which is in the left and right sides) formed in a concave shape open to the left and right. FIG. 8A to FIG. 8C). The partition wall 51a is formed with a through hole 51c for inserting a rivet 53 mentioned below through the through hole 51c.

[0064] The two second arm weights 52 and the second arm weight 52 are both made of a material (metal, such as iron; the same applies to the following) with a greater specific gravity than the second arm 32A, and are each formed into an elongated and narrow plate shape extending in the front-to-back direction and having the same shape as each other. Each second arm weight 52 has a mounting hole 52, and the mounting hole 52 is formed by each second arm weight 52 at the center of each second arm weight 52. The two second arm weights 52 and the second arm weight 52 are respectively inserted into the left weight mounting part 51b and the right weight mounting part 51b of the second arm 32A from the outside, and are fixed to the left weight mounting part 51b and the right weight mounting part 51b of the second arm 32A under a state in which the rivet 53 is inserted into the two mounting holes 52a and the mounting hole 52a and the through hole 51c of the partition wall 51a.

[0065] According to the second arm 32A of the present embodiment, since the second arm weight 52 made of a material having a larger specific gravity than the second arm 32A and the second arm weight 52 are installed in the second arm 32A, the moment of inertia of the second arm 32A is increased by increasing the weight of the second arm 32A. This makes it possible to provide a sufficient response to key depression, whereby an excellent touch can be obtained during key depression. Furthermore, an excellent touch can be obtained by increasing the weight of the second arm 32A, whereby an increase in the weight of the first arm 31 can be suppressed. Thus, compared with a case in which only the weight of the first arm 31 is increased, the responsiveness of the key 2 that has been depressed when the key 2 performs a pivot return movement to its original position can be improved, whereby appropriate string striking repeatability of the key 2 can be obtained.

[0066] In addition, the second arm weight 52 is provided in front of the bearing portion 41, i.e., in front of one of the second pivot shafts 19a, with which the bearing portion 41 is engaged, and therefore, the second arm 32A becomes easy to pivotally move in a direction in which the second arm front side connecting portion 45 formed at the front end of the second arm 32A and which has been moved upward by the pressing of the key 2 moves downward in accordance with the release of the key 2. As a result, the first arm 31 (the first arm front side connecting portion 35 of the first arm 31 formed at the front end of the first arm 31 having been pressed by the pressing of the key 2) is further facilitated to perform a pivotal return movement to its original position. According to the above, the touch and responsiveness of the key 2 when the key 2 is pressed can be further improved.

[0067] 9A to 9C A second arm 32B according to a second embodiment of the present invention is shown, wherein: Fig. 9A It is a perspective view. Fig. 9Bis a side view, and Fig. 9C 1 is an exploded perspective view. The second arm 32B of this embodiment includes, in addition to the second arm weight 52 described above in the first embodiment, an L-shaped weight 54 (second arm weight) mounted near the bearing portion 41 of the second arm 32B. The second arm 32B has two left L-shaped weight mounting portions 41a and right L-shaped weight mounting portions 41a (only one of which is located on the left and right sides thereof) disposed thereon. 9A to 9C ), the two left L-shaped weight mounting portions 41a and the right L-shaped weight mounting portion 41a are each formed into a concave shape open to the left and right and extend continuously from the rear of the bearing portion 41 to below the bearing portion 41.

[0068] The two L-shaped weights 54 and the L-shaped weight 54 are each made of a material having a greater specific gravity than the second arm 32B and are formed into a substantially L-shape, and both have the same shape as each other. The two L-shaped weights 54 and the L-shaped weight 54 are fitted into the corresponding left L-shaped weight mounting portion 41a and the right L-shaped weight mounting portion 41a of the second arm 32B from the outside, and are fixed to the weight mounting portion 41a and the weight mounting portion 41a by combining.

[0069] According to the second arm 32B of the present embodiment, not only the same advantageous effects as those provided by the second arm 32A described above of the first embodiment can be obtained, but also the weight of the second arm 32B can be increased relatively easily.

[0070] FIG. 10A to FIG. 10C is a view of a second arm 32C according to a third embodiment of the present invention, wherein Fig. 10A It is a perspective view. Fig. 10B is a side view, and Fig. 10C : is an exploded perspective view. The second arm 32C is provided with a weight accommodating portion 56, and the weight accommodating portion 56 is formed so that the weight accommodating portion 56 extends through the connecting portion 51 in the left-right direction, so that a single second arm weight 55 is installed in the second arm 32C in a state accommodated in the second arm 32C. In the weight accommodating portion 56, a total of four latching lugs 57 are formed two by two at the corresponding upper and lower positions of the opening on the right side of the weight accommodating portion 56, and a total of two latching lugs 58 and latching lugs 58 are formed one by one at the corresponding upper and lower positions of the opening on the left side of the weight accommodating portion 56.

[0071] The second arm weight 55 of the present embodiment is made of a material having a greater specific gravity than the second arm 32C, and is formed into a block shape extending in the front-rear direction. The second arm weight 55 is accommodated in the weight accommodating portion 56 by being inserted into the weight accommodating portion 56 from the left. Furthermore, in this case, the second arm weight 55 in the weight accommodating portion 56 is fixed in the weight accommodating portion 56 in a state of being latched with the latch lugs 57 and the latch lugs 58 on the left and right sides of the weight accommodating portion 56 from the left and right directions.

[0072] According to the second arm 32C of this embodiment, not only can the same advantageous effects as those provided by the second arm 32A of the first embodiment be obtained, but the second arm weight 55 can also be easily installed in the second arm 32C simply by inserting the second arm weight 55 into the weight accommodating portion 56.

[0073] FIG. 11A to FIG. 11C is a view of a second arm 32D according to a fourth embodiment of the present invention, wherein Fig.11A It is a perspective view. Fig. 11B is an exploded perspective view, and Fig. 11C 32D is an exploded perspective view of the second arm weight. The second arm 32D is different from the second arm 32C described above in the third embodiment only in terms of the second arm weight 59. That is, the second arm weight 59 is composed of: a block weight body 59a, which is made of the same material as the second arm weight 55 of the third embodiment and extends in the front-to-back direction; and a square tubular weight cover 59b, which is installed on the weight body 59a so that the square tubular weight cover 59b covers the outside of the weight body 59a, specifically, the part except its front and rear ends. The weight cover 59b is made of, for example, a soft synthetic resin or an elastic synthetic resin.

[0074] According to the second arm 32D of the present embodiment, during the operation of the second arm 32D according to the key pressing, the second arm weight 59 (weight body 59a) is prevented from rattling or vibrating in the weight accommodating portion 56. This makes it possible to prevent the second arm weight 59 from generating noise during the operation of the second arm 32D.

[0075] Fig. 12A and Fig. 12B A second arm 32E according to a fifth embodiment of the present invention is shown, wherein: Fig. 12A is a perspective view, and Fig. 12B51. It is a side view. Most of the second arm 32E is made of synthetic resin, and a part of the second arm 32E is formed by a second arm weight. Specifically, in the connecting portion 51, the second arm weight 61 is arranged so that the second arm weight 61 is suspended downward from the lower surface of the top plate 60 extending flatly in the front-to-back direction. The second arm weight 61 is formed in a plate shape with a predetermined thickness, and is arranged so that the second arm weight 61 extends from the central part of the lower surface of the top plate 60 in the front-to-back direction.

[0076] When manufacturing the second arm 32E, the second arm 32E in which the second arm weight 61 is integrally formed may be obtained by insert molding in which the second arm weight 61 is set in a mold and molten synthetic resin is injected into the mold.

[0077] According to the second arm 32E of the present embodiment, the same advantageous effects as those provided by the second arm 32A described above in the first embodiment can be obtained. In addition, the step of installing the second arm weight 61 during the manufacture of the second arm 32E can be omitted, which makes it relatively easy to manufacture the second arm 32E provided with the second arm weight 61.

[0078] Note that the second arm 32 of the keyboard device 1 according to the present invention is by no means limited to the first to fifth embodiments described above, but can be practiced in various forms. For example, although in the corresponding second arms 32A and the second arm 32B of the first and second embodiments, the second arm weight 52 and the L-shaped weight 54 are installed on the left and right sides of the second arm 32A and the second arm 32B, the second arm weight 52 and the L-shaped weight 54 can also be installed on one of the left and right sides of the second arm 32A and the second arm 32B as needed. Furthermore, although by way of example, metal (such as iron) is mentioned as the material of the second arm weight, the present invention is not limited thereto, but can use any suitable material as long as it has a greater specific gravity than the second arm 32, and various materials can be used, such as metals other than iron and composite materials made of metal and synthetic resin.

[0079] Furthermore, the details of the configurations of the second arms 32A to 32E shown in the first to fifth embodiments are given only by way of example, and the details can be modified as appropriate within the scope of the subject matter of the present invention.

Claims

1. A keyboard device for a keyboard musical instrument, comprising: Keyboard dock; A key extending a predetermined length in the front-rear direction and disposed on the keyboard base; as well as a key support mechanism engaged with the keyboard base and arranged so as to support the key from below, the key support mechanism causing the depressed key to operate when the key is depressed so that the key pivotally moves about a virtual fulcrum located behind a rear end of the key, Wherein, the key support mechanism comprises: a first arm configured to extend a predetermined length in the front-rear direction and to be swingably engaged with a first pivot shaft provided on the keyboard base, the first arm having a front end pivotally and slidably connected to a front portion of the key; and The second arm is configured to extend a predetermined length in the front-rear direction and is swingably engaged with a second pivot shaft provided on the keyboard base at a position rearward of the first pivot shaft, the second arm having a rear end pivotally connected to a rear portion of the key and including a second arm front side connecting portion, the second arm front side connecting portion being provided in front of the second pivot shaft and being pivotally and slidably connected to a first arm rear side connecting portion of the first arm rearward of the first pivot shaft, and, Wherein, the second arm is provided with a second arm weight made of a material having a greater specific gravity than the second arm.

2. The keyboard device according to claim 1, wherein: The second arm weight is disposed in front of the second pivot axis and / or around the second pivot axis.

3. The keyboard device according to claim 1, wherein: The second arm weight is mounted on at least one of a left side and a right side of the second arm.

4. The keyboard device according to claim 1, wherein: The second arm includes a weight receiving portion extending through the second arm in the left-right direction, and, The second arm weight is installed in the second arm in a state of being accommodated in the weight accommodating portion by being inserted into the weight accommodating portion from the outside.

5. The keyboard device according to claim 4, wherein: The second arm weight is accommodated in the weight accommodation portion in a state in which the exterior of the second arm weight is covered with a predetermined synthetic resin.

6. The keyboard device according to claim 1, wherein: The second arm is manufactured by molding a synthetic resin, and the second arm weight is integrally formed with the second arm when the second arm is molded.

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