Electronic keyboard musical instrument

Abstract

To provide an electronic keyboard musical instrument capable of suppressing rattle and deflection, which occur in a housing.SOLUTION: An electronic keyboard musical instrument 10 includes: a substantially rectangular housing 12 having a bottom 12b facing an installation face; and a keyboard which is provided in the housing 12 and has a plurality of keys arranged in a longitudinal direction of the housing 12. The bottom 12b includes: a plurality of fixing legs 20a, 20b, 20c and 20d which protrude from the bottom 12b to an installation face side and contact the installation face to support the housing 12 from below; and first adjustment legs 22L and 22R which protrude from the bottom 12b to the installation face side at the outside of the fixing legs 20a, 20b, 20c and 20d in the arranging direction of the keys and are arranged apart from the installation face.SELECTED DRAWING: Figure 2

Description

[Technical Field]

[0001] The present invention relates to an electronic keyboard instrument. [Background technology]

[0002] Electronic keyboard instruments are typically placed on a desk or other surface for use. For example, Patent Document 1 discloses an electronic keyboard instrument with four rubber feet on its bottom. The rubber feet contact the horizontal surface and support the housing of the electronic keyboard instrument. If the housing flexes when a player strikes a key, it can cause adjacent keys to come into contact with each other, or the feel of the keystrokes can vary depending on the position on the key, potentially reducing the playability of the electronic keyboard instrument. Therefore, measures to suppress housing flex are typically taken by increasing the number of legs. However, because a minimum level of support is possible for a housing with three or four legs, excessively increasing the number of legs can make the housing more susceptible to wobbling. There is a trade-off between suppressing housing wobble and suppressing flex. While the amount of flex in a housing varies depending on the housing material, this problem is generally more likely to occur when the housing has a relatively long longitudinal length.

[0003] Here, an electronic keyboard instrument (hereinafter referred to as a "61-key model") with a total of 61 keys, including both white and black keys, is known. In this type of electronic keyboard instrument, fixed legs that contact the support surface (that constantly support the housing 12) are arranged at the four corners of the bottom facing the support surface, and two adjustable legs are sometimes arranged at the front and rear of the bottom of the housing in the center, positioned so as to be spaced apart from the support surface when the performer is not striking the keys. The adjustable legs come into contact with the support surface and support the center of the housing when the performer bends the housing toward the support surface. In this way, the adjustable legs suppress excessive bending of the housing, improving playability. Furthermore, because the adjustable legs do not come into contact with the support surface when the housing is not bending, they are less likely to cause wobble in the housing. In this way, the fixed legs and adjustable legs simultaneously suppress both wobble and bending of the housing. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Japanese Patent Application Laid-Open No. 2002-215156 Summary of the Invention [Problem to be solved by the invention]

[0005] Even in electronic keyboard instruments with keyboards that have more keys than the above-mentioned models with a relatively small number of keys, it is expected that fixed legs will be placed at the four corners of the bottom and adjustable legs will be placed in the center, just like in conventional models, to evenly support the housing and prevent wobbling. However, in electronic keyboard instruments with many keys, the length in the left-right direction (longitudinal direction) in which the keys are arranged is longer than in models with a relatively small number of keys, so the center of the housing is more likely to flex (the amount of flex is greater) than in conventional models. Therefore, even if fixed legs are placed at the four corners, the amount of flexure in the center is so large that adjacent keys can come into contact with each other, which is a problem. SUMMARY OF THE INVENTION It is therefore an object of the present invention to provide an electronic keyboard instrument that can suppress rattles and warping that occur in the housing. [Means for solving the problem]

[0006] An electronic keyboard instrument according to one embodiment of the present invention comprises a housing having a generally rectangular shape with a bottom facing a support surface, and a keyboard provided on the housing and having a plurality of keys arranged in the longitudinal direction of the housing, the bottom having a plurality of fixed legs that protrude from the bottom toward the support surface and contact the support surface to support the housing from below, and a first adjustable leg that protrudes from the bottom toward the support surface outside the fixed legs in the key arrangement direction and is positioned at a distance from the support surface. [Effects of the Invention]

[0007] According to the present invention, it is possible to provide an electronic keyboard instrument that can suppress rattles and warpage that occur in the housing. [Brief explanation of the drawings]

[0008] [Figure 1] FIG. 2 is a perspective view of the keyboard model according to the embodiment, seen from above. [Figure 2] FIG. 2 is a perspective view of the keyboard model according to the embodiment, seen from below. [Figure 3] FIG. 2 is a cross-sectional view of the keyboard model according to the embodiment, taken along the line III-III shown in FIG. 1. [Figure 4] FIG. 2A is a top view of a keyboard model according to an embodiment, FIG. 2B is a front view of the keyboard model according to an embodiment, and FIG. 2C is a bottom view of the keyboard model according to an embodiment. [Figure 5] FIG. 10 is a front view of a part of the keyboard model according to the embodiment, showing the positional relationship between the fixed legs and the adjustable legs and the placement surface. DETAILED DESCRIPTION OF THE INVENTION

[0009] The structure of a keyboard model (electronic keyboard instrument) 10 according to one embodiment of the present invention will be described below with reference to FIGS. 1 to 5. In this embodiment, a keyboard model 10 equipped with a keyboard 14 having 76 keys will be illustrated. The keyboard model 10 shown in FIG. 1 includes a housing 12 and a keyboard 14 having a plurality of keys arranged in the longitudinal direction of the housing 12. A group of keys 14C located between (inside) the sixth white key 14aL from the left and the sixth white key 14aR from the right corresponds to the range of a conventional 61-key keyboard model, and is a range that is struck relatively more frequently than the group of keys 14L located to the left (outside) of the sixth white key 14aL from the left and the group of keys 14R located to the right (outside) of the sixth white key 14aR from the right. In the following description, as shown in Fig. 1, the direction in which the keys on the keyboard 14 are arranged is defined as the left-right direction (the left side of Fig. 1 is the left direction), and the direction in which the keys on the keyboard 14 extend is defined as the front-to-back direction (the front side of Fig. 1 is the front direction). The left-to-right direction and the front-to-back direction are perpendicular to each other. The direction perpendicular to the left-to-right direction and the front-to-back direction is defined as the up-to-down direction (the upper side of Fig. 1 is the up direction).

[0010] As shown in FIG. 1, the housing 12 has a generally elongated rectangular shape with the left-right direction as the longitudinal direction. The housing 12 has an upper cover 12a and a bottom portion 12b. Specifically, the housing 12 is divided into the upper cover 12a and the bottom portion 12b. The upper cover 12a and the bottom portion 12b are each formed of a resin material. A circuit board (not shown) and the like are housed inside the housing 12. When viewed from above, the upper cover 12a has a generally U-shape that opens to the front. The upper cover 12a has a left end portion 12aL, a right end portion 12aR, and a middle portion 12aC. The left end portion 12aL and the right end portion 12aR have a generally rectangular parallelepiped shape extending in the front-rear direction. The middle portion 12aC has a generally rectangular parallelepiped shape extending in the left-right direction. Therefore, the left end 12aL, the right end 12aR, and the middle portion 12aC each have an upper surface, a left surface, a right surface, a front surface, and a rear surface. The left surface of the middle portion 12aC is connected to the upper end of the right surface of the left end 12aL. The right surface of the middle portion 12aC is connected to the upper end of the left surface of the right end 12aR. The upper surfaces of the middle portion 12aC, the left end 12aL, and the right end 12aR are slightly inclined downward from the rear to the front.

[0011] Various operation switches 26, such as a power switch, are arranged in the left-right direction at the front center of the top surface of the middle section 12aC. A volume dial 28 is provided to the left of the operation switches 26. A known keystroke mechanism is provided in the space between the keyboard 14 and the bottom section 12b to realize keystroke intervals and tones similar to those of a real piano when a player presses each key on the keyboard 14. Speaker boxes 16LB and 16RB (see FIG. 1, etc.) are installed inside the left and right sides of the middle section 12aC, respectively. The speaker boxes 16LB and 16RB are approximately rectangular with the longitudinal direction extending left-right. Speakers (sound-emitting members) 16L and 16R are housed inside the speaker boxes 16LB and 16RB, respectively. Because keyboard model 10 has a relatively large number of keys, speaker boxes 16LB and 16RB are expected to extend longitudinally. However, if the fixed legs were located at the four corners of housing 12, excessive bending of speaker boxes 16LB and 16RB would occur as housing 12 bends, potentially deforming or damaging speakers 16L and 16R. Therefore, speaker 16L is located near fixed legs 20a and 20c, and speaker 16R is located near fixed legs 20c and 20d. Specifically, speakers 16L and 16R are located near the line connecting fixed legs 20a, 20b, 20c, and 20d. More specifically, as shown in FIG. 4(c), a portion of speaker 16L overlaps with the line connecting fixed legs 20a and 20b in a plan view. In a plan view, a portion of speaker 16R overlaps with the line segment connecting fixed leg 20c and fixed leg 20d. Speakers 16L and 16R are firmly supported, particularly in the front-to-rear direction, and are less susceptible to bending that occurs in housing 12. Speakers 16L and 16R are, for example, sealed speakers having sealed portions. Speaker grills (not shown) corresponding to speakers 16L and 16R are provided on the left and right sides of the upper surface of middle portion 12aC, respectively.

[0012] As shown in Figs. 2 and 4(b) and (c), the bottom 12b is a plate-like member extending in the left-right direction, and faces the placement surface LS (see Fig. 5) when the keyboard model 10 is placed on the placement surface LS. The bottom 12b has a handle 18, multiple fixed legs 20a, 20b, 20c, and 20d, multiple first adjustable legs 22L and 22R, and multiple second adjustable legs 24F and 24B. The handle 18 is located at the center rear end of the bottom 12b. When viewed from below, the handle 18 has a generally rectangular shape with its longitudinal direction extending in the left-right direction, and is recessed.

[0013] The fixed legs 20a, 20b, 20c, and 20d are flat, cylindrical members extending vertically. The fixed legs 20a, 20b, 20c, and 20d protrude downward (toward the placement surface LS) from the bottom 12b. Specifically, the fixed legs 20a, 20b, 20c, and 20d are arranged on the bottom 12b in the left-right direction so that line segments connecting the fixed legs 20a, 20b, 20c, and 20d form a rectangle RS extending along the longitudinal direction of the housing. The fixed leg 20a is located on the left front side of the bottom 12b, and the fixed leg 20c is located on the right front side of the bottom 12b. More specifically, the fixed leg 20a overlaps with the front end of the sixth white key 14aL from the left when viewed from above, and the fixed leg 20c overlaps with the front end of the sixth white key 14aR from the right when viewed from above. Furthermore, fixed leg 20b is located at the rear left side of bottom 12b, and fixed leg 20d is located at the rear right side of bottom 12b. In other words, fixed legs 20a, 20b, 20c, and 20d are not located below the extreme (left and right) keys. If fixed legs were located at the four corners of housing 12, which has a relatively large number of keys, the amount of flex in the center would be excessively large, which could impair contact between adjacent keys and the feeling of uniform keystrokes. Therefore, fixed legs 20a, 20b, 20c, and 20d are positioned so that the distance between them is as long as possible within the allowable flexure of housing 12.

[0014] 5, when the keyboard model 10 is placed on the mounting surface LS, the fixing legs 20a, 20b, 20c, and 20d are in constant contact with the mounting surface LS, thereby supporting the housing 12 from below. The fixing legs 20a, 20b, 20c, and 20d are made of an elastic material such as rubber. Therefore, even if the mounting surface LS is uneven, the elastic deformation of the fixing legs 20a, 20b, 20c, and 20d will reduce the unevenness of the mounting surface LS, thereby preventing the housing 12 from rattling.

[0015] Fixed leg 20b is located near speaker 16L, and fixed leg 20d is located near speaker 16R. Since fixed legs 20b and 20d are always in contact with the placement surface LS, the portions of housing 12 near fixed legs 20b and 20d are less likely to bend.

[0016] The first adjustable legs 22L, 22R are flat, cylindrical members extending in the vertical direction. The first adjustable legs 22L, 22R protrude downward (toward the placement surface LS) from the bottom 12b and are spaced apart from the placement surface LS. Specifically, when viewed from below, the first adjustable legs 22L, 22R are arranged symmetrically on the bottom 12b outside a rectangle RS extending in the left-right direction formed by line segments connecting the fixed legs 20a, 20b, 20c, and 20d (in other words, outside the fixed legs 20a, 20b, 20c, and 20d in the left-right direction). More specifically, the first adjustable leg 22L is arranged below the end (leftmost) key and in front of the extension direction of the key. The first adjustable leg 22R is arranged below the end (rightmost) key and in front of the extension direction of the key. Because fixed legs 20a, 20b, 20c, and 20d are not located at the four corners of housing 12, when keys 14L and 14R located outside the fixed legs are pressed, a force acts on key group 14c, causing it to lift upward with the fixed legs as the fulcrum, due to the principle of levers. By locating first adjustable legs 22L and 22R outside fixed legs 20a, 20b, 20c, and 20d, the generation of this lifting force can be suppressed, providing a stable keystroke feel.

[0017] The first adjustable legs 22L, 22R come into contact with the support surface LS as the housing 12 bends when the keys 14 are pressed. By coming into contact with the support surface LS, the first adjustable legs 22L, 22R support the housing 12 with elastic deformation, preventing the housing 12 from bending excessively. As shown in FIG. 2, when the keys 14 are not being pressed (when the housing 12 is not bending), the first adjustable legs 22L, 22R have a slight first clearance (clearance) d1 (for example, 0.3 mm) from the support surface LS. The first adjustable legs 22L, 22R are made of an elastic material such as rubber.

[0018] The second adjustable legs 24F, 24B are flat, cylindrical members extending in the vertical direction. The second adjustable legs 24F, 24B protrude downward (toward the placing surface LS) from the bottom 12b and are spaced apart from the placing surface LS. The second adjustable legs 24F, 24B come into contact with the placing surface LS as the housing 12 bends when the keys 14 are struck. By coming into contact with the placing surface LS, the second adjustable legs 24F, 24B support the housing 12 with elastic deformation and prevent excessive bending of the housing 12. As shown in FIG. 2, when the keys 14 are not struck (when the housing 12 is not bent), the second adjustable legs 24F, 24B have a second clearance (clearance) d2 from the placing surface LS that is larger than the first clearance d1 (for example, 1.5 mm). The reason why the second clearance d2 is larger than the first clearance d1 is that the amount of deflection of the housing 12 due to a keystroke depends on the distance from the keystroke position to the nearest fixed leg. In other words, the amount of deflection of the housing 12 is smaller when the left end 12aL or the right end 12aR is struck than when the middle portion 12aC (especially the central key) is struck. In the case of the keyboard model (electronic keyboard instrument) 10, the distance from the first adjustable leg 22L to the fixed leg 20a is smaller than the distance from the second adjustable leg 24F to the fixed leg 20a, and the amount of deflection near the first adjustable leg 22L is smaller than the amount of deflection near the second adjustable leg 24F. Therefore, the second clearance d2 is set larger than the first clearance d1. The second adjustable legs 24F and 24B are made of an elastic material such as rubber.

[0019] The second adjustable legs 24F and 24B are arranged inside the rectangle RS (inside the fixed legs 20a, 20b, 20c, and 20d in the key arrangement direction). Specifically, the second adjustable legs 24F and 24B are arranged in the center of the bottom 12b in the key arrangement direction, and on one side and the other side in the extension direction of the keys. More specifically, the second adjustable leg 24F is located in the front of the center of the bottom 12b in the left-right direction. The second adjustable leg 24B is located in the rear of the center of the bottom 12b in the left-right direction. In other words, the second adjustable leg 24B is located in front of the handle 18.

[0020] As described above, the first adjustable leg 22L, the fixed leg 20a, the second adjustable leg 24F, the fixed leg 20c, and the first adjustable leg 22R are arranged in this order from left to right at the front of the bottom 12b. The fixed leg 20b, the second adjustable leg 24B, and the fixed leg 20d are arranged in this order from left to right at the rear of the bottom 12b. The fixed legs 20a, 20b, 20c, and 20d, the first adjustable legs 22L and 22R, and the second adjustable legs 24F and 24B all have the same height as components, but are arranged at different heights on the bottom 12b. Furthermore, when the heights as components are different (when the heights of the first adjustable legs 22L and 22R and the second adjustable legs 24F and 24B are shorter than the heights of the fixed legs 20a, 20b, 20c, and 20d), material costs can be reduced.

[0021] The keyboard 14 is disposed in an area of ​​the housing 12 surrounded by the left end 12aL, the right end 12aR, and the middle section 12aC, and multiple keys of the keyboard 14 are arranged in the left-right direction. In other words, multiple keys of the keyboard 14 are lined up in the left-right direction in front of the middle section 12aC. For example, if the keyboard 14 has 76 keys, it includes 36 white keys 14a and 25 black keys 14b.

[0022] Next, the effects of the keyboard model 10 will be described. Placing fixed legs at the four corners of the keyboard model 10 and adjusting legs between them increases the amount of flex in the housing 12, potentially causing adjacent keys to come into contact with each other. In other words, there is a limit to how much flex can be suppressed by placing fixed legs at the four corners of the housing 12 and adjusting legs between them. While shortening the distance between the central adjusting legs and the mounting surface is conceivable to suppress the amount of flex, as the total number of keys increases, the distance between the adjusting legs and the mounting surface must be excessively short to compensate for the increased amount of flex. This approach ultimately becomes equivalent to placing fixed legs in the center, ultimately failing to eliminate wobble. For this reason, in the keyboard model 10 of this embodiment, the fixed legs 20a, 20b, 20c, and 20d are positioned so that the distance between them is as long as possible within the range that allows for flexure of the housing 12, and the first adjustable legs 22L and 22R are positioned outside the fixed legs 20a, 20b, 20c, and 20d. Therefore, rattle and warping occurring in the housing 12 are suppressed.

[0023] In keyboard model 10 of this embodiment, four fixed legs 20a, 20b, 20c, and 20d reduce material costs and reduce wobbling in housing 12 compared to a keyboard with five or more fixed legs that are constantly in contact with support surface LS. Second adjustable legs 24F and 24B also reduce excessive bending in housing 12 caused by keystrokes on keys 14C. Therefore, even with keyboard model 10 of this embodiment, which has keys 14C that are struck relatively frequently, housing 12 is effectively supported when the keys are struck, providing playability equivalent to that of a 61-key model.

[0024] In addition, in the keyboard model 10 of this embodiment, the first adjustable legs 22L, 22R suppress excessive bending of the housing 12 caused by keystrokes on the keys 14L, 14R. Furthermore, adjustable legs (first adjustable leg 22L, second adjustable leg 24B) and fixed legs (fixed leg 20a, fixed leg 20c) are arranged alternately in the left-right direction at the front of the bottom 12b. Adjustable legs (second adjustable leg 24B) and fixed legs (fixed leg 20b, fixed leg 20d) are arranged alternately in the left-right direction at the rear of the bottom 12b. In this way, by arranging the first adjustable legs 22L, 22R and the second adjustable legs 24F, 24B between the fixed legs 20a, 20b, 20c, 20d that come into contact with the placement surface LS, excessive bending of the housing 12 is effectively suppressed. Furthermore, since the first adjustable legs 22L and 22R effectively suppress bending that occurs in the housing 12, it is possible to minimize the number of adjustable legs, thereby reducing manufacturing costs.

[0025] Furthermore, in the keyboard model 10 of this embodiment, when there is no deflection in the housing 12 (when the keys 14L, 14R are not being struck), the first clearance d1 between the first adjustable legs 22L, 22R and the mounting surface LS is smaller than the second clearance d2 between the second adjustable legs 22F, 22B and the mounting surface LS when there is no deflection in the housing 12. With this configuration, since the keys toward the center of the keyboard 14 are struck relatively more frequently than the keys toward the ends of the keyboard 14, deflection of the housing 12 caused by keystrokes is uniformized. This allows the player to obtain a uniform keystroke feel.

[0026] Typically, the speakers 16L and 16R are positioned near the left and right ends of the housing to achieve a stereophonic sound and to assign low and high frequencies to produce well-balanced sounds. However, the speakers 16L and 16R are susceptible to deformation or damage caused by bending of the housing 12, and may become dislodged due to clearance between the speakers 16L and 16R and other components. Therefore, simply placing the fixed legs at the four corners of the housing increases the distance between the fixed legs and the speakers 16L and 16R, resulting in a significant impact on the speakers 16L and 16R due to bending. In contrast, in the keyboard model 10 of this embodiment, the speakers 16L and 16R are firmly supported by being positioned near the fixed legs 20a, 20b, 20c, and 20d. Therefore, the speakers 16L and 16R are less susceptible to the bending of the housing 12, and deformation and damage are suppressed.

[0027] Furthermore, since the left hand, which plays the accompaniment, is more likely to press multiple keys simultaneously, and the keys are struck more forcefully, and the keys at the ends are used more frequently, as a variation of the above embodiment, the clearance from the support surface LS of the left-hand first adjustable leg 22L may be made larger than the clearance from the support surface LS of the right-hand first adjustable leg 22R.

[0028] The above-described embodiments are presented as examples and are not intended to limit the scope of the invention. These novel embodiments may be embodied in various other forms, and various omissions, substitutions, and modifications may be made without departing from the spirit of the invention. The present invention may be applied to, for example, an electronic keyboard instrument with a keyboard having 61 or 88 keys. These embodiments and their modifications are included within the scope and spirit of the invention, and are also included in the scope of the invention and its equivalents as defined in the accompanying claims. [Explanation of symbols]

[0029] 10: keyboard model, 12: housing, 12b: bottom, 14: keyboard, 20a, 20b, 20c, 20d: fixed legs, 22L, 22R: first adjustable legs, LS: mounting surface

Claims

1. a substantially rectangular housing having a bottom portion facing the mounting surface; a keyboard provided on the housing and having a plurality of keys arranged in the longitudinal direction of the housing; The bottom portion has a plurality of fixed legs that protrude from the bottom portion toward the placement surface and contact the placement surface to support the housing from below, and a first adjustable leg that protrudes from the bottom portion toward the placement surface on the outer side of the fixed legs in the key arrangement direction and is positioned at a distance from the placement surface. Electronic keyboard instrument.

2. the fixing legs are provided at four positions on the bottom portion corresponding to vertices of an imaginary rectangle extending along the longitudinal direction of the housing, Each of the fixing legs is not positioned below the endmost key of the plurality of keys, the first adjustable leg is positioned below the endmost key; 2. The electronic keyboard instrument according to claim 1.

3. The first adjustable leg is disposed on one side in the extension direction of the key.

2. The electronic keyboard instrument according to claim 1.

4. The first adjustable leg is disposed on the front side in the extension direction of the key.

4. The electronic keyboard instrument according to claim 3.

5. the bottom portion has a second adjustable leg that protrudes from the bottom portion toward the placement surface, is spaced apart from the placement surface, and is disposed inside the fixed leg in the arrangement direction.

2. The electronic keyboard instrument according to claim 1.

6. a plurality of the second adjustable legs; the second adjustable legs are disposed at a center portion of the bottom portion in the arrangement direction and on one side and the other side in the extension direction, 6. The electronic keyboard instrument according to claim 5.

7. a clearance between the first adjustable leg and the mounting surface is smaller than a clearance between the second adjustable leg and the mounting surface; 7. The electronic keyboard instrument according to claim 5 or 6.

8. A sound emitting member is provided, the sound emitting member is provided in the vicinity of a line segment connecting the plurality of fixed legs in a plan view of the housing.

2. The electronic keyboard instrument according to claim 1.

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