JP2006099005A - Velocity-determining device of keyboard instrument - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a velocity-determining device of a keyboard instrument that can properly determine the velocity through relatively simple processing, regardless of the playing method, key depressing strength etc., in a musical performance. <P>SOLUTION: The velocity-determining device 1 of the keyboard instrument 2 which determines the velocity for controlling the sound volume, according to the key depressing strength of a rotatable key 4 is equipped with a key speed data detecting means 16 of detecting key speed data, representing the rotating speed of the key 4 in three or more mutually different sections within the rotation range of the key 4, a key speed data excluding means 23 of excluding the maximum data and minimum data from a plurality of detected key speed data, and a velocity-determining means 23 of determining the velocity V based upon the remaining key speed data, after maximum and minimum data have been excluded. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention is applied to, for example, an electronic keyboard instrument such as an electronic piano, or a composite piano such as a mute piano or an auto-playing piano, and has a velocity as a parameter representing string striking strength according to detected key pressing information. The present invention relates to a velocity determining apparatus for determining a keyboard instrument.

  When playing an electronic piano as described above, or when muting a piano, it is common to detect the key speed of a key that rotates when the key is pressed and determine the velocity according to the detected key speed. The volume to be generated is determined based on the velocity that has been generated. This is because the volume of an acoustic piano or the like is determined by the hammering speed of the hammer when the string is struck, and this stringing speed is basically determined according to the key speed. Also, determining the velocity without directly based on the key speed is different in the performance method, etc., even if the key speed is the same, the final stringing speed will be different, and the volume to be generated accordingly This is because they are also different.

  As a conventional apparatus for determining such a velocity, for example, one disclosed in Patent Document 1 is known. This velocity determining device is applied to an automatic performance piano. This automatic performance piano is configured to be switchable between a recording mode for recording performance data during performance by a performer and a playback mode for reproducing recorded performance data, and includes a plurality of keys, a hammer for striking a string, , Provided at the rear part of the keyboard, and actuated with the rotation of the key to provide an action for rotating the hammer. Further, a shutter is integrally provided on the lower surface of the front end portion of each key, and four photocouplers are arranged as measurement points along the movement path of the shutter. With such a configuration, when the key is depressed, the shutter sequentially shields the four photocouplers as the key is rotated, and a detection signal corresponding to the light is output from each photocoupler.

  With this velocity determination device, when a performer presses a key, the key press is performed regardless of the type of key operation (key press strength, continuous strike, touch depth such as when touching very shallow or shallow). There is a section where the key speed is constant from the start to the end (hereinafter referred to as “constant speed section”), the timing at which such a constant speed section appears differs between the types of key operations, and Regardless of the type of key operation, the velocity is determined from the viewpoint that there is a certain relationship between the key speed obtained in the constant speed section and the string striking speed. Specifically, based on the timing when each of the four photocouplers is shielded from light, the key movement time in three measurement sections defined by each two adjacent photocouplers is calculated. The type of key operation is specified accordingly. Next, one constant speed section is selected from the three measurement sections according to the specified type of key operation, and specified as a feature section. Next, a string striking speed (velocity) is determined based on a relationship between a preset key speed and a string striking speed in accordance with the key speed obtained in the characteristic section.

  As described above, in this velocity determining apparatus, the type of key operation is specified from the key movement times obtained in the three measurement sections, and the characteristic section is selected according to the type of key operation. However, the actual key operation is very complicated, and the appearance of constant-velocity sections varies accordingly.Therefore, in the above method, the type of key operation and the identification of the characteristic section corresponding to it are appropriately specified. As a result, the velocity may not be determined properly. For example, when a step where the key pressing depth hardly changes during the key press (hereinafter referred to as “slow step”) occurs, the timing of the slow step occurs near the start of the key press Since the transition of the key speed is greatly different from when it occurs near the end, there is a possibility that the type of the key operation is erroneously specified. In such a case, a reversal phenomenon occurs in which the magnitude relationship between the key-pressing strength and the determined velocity at the time of actual performance is reversed, and a low-pitched tone is emitted even though the key is strongly pressed. On the contrary, even if the key is pressed weakly, a loud sound is generated. In addition, it is necessary to specify a key operation type according to the key movement time and a feature section according to the key operation type, and the key movement time and the key for performing these identifications. There is a problem that the relationship between the type of operation and the relationship between the type of key operation and the feature section must be determined in advance, which complicates the entire arithmetic processing.

  The present invention has been made to solve such a problem, and it is possible to appropriately determine the velocity by a relatively simple calculation process regardless of the performance method and the key depression strength at the time of performance. An object of the present invention is to provide a velocity determining device for a keyboard instrument.

Japanese Patent Publication No.7-113825

  In order to achieve this object, the invention according to claim 1 is a velocity determining device for a keyboard instrument that determines a velocity in order to control the volume in accordance with the key pressing strength of a rotatable key. The key speed data detecting means for detecting the key speed data representing the key rotation speed in three or more different sections within the rotation range of the key, and the maximum speed from the plurality of detected key speed data. Key speed data excluding means for excluding value data and minimum value data, and velocity determining means for determining velocity based on the remaining key speed data excluding maximum value data and minimum value data. Features.

  According to the velocity determining apparatus for a keyboard instrument, the key speed data detecting means detects key speed data of three or more different predetermined sections within the key rotation range, and the key speed data excluding means comprises: The maximum value data and the minimum value data are excluded from the detected key speed data. The velocity determining means determines the velocity based on the remaining key speed data excluding the maximum value data and the minimum value data. As described above, according to the present invention, the maximum value data and the minimum value data are excluded from the key speed data when determining the velocity. For example, if a slow step as described above occurs when a key is pressed, the key speed tends to decrease temporarily and then increase rapidly, so the minimum value data and maximum value data are excluded. By doing so, it is possible to eliminate the influence of such a gradual stage, thereby preventing problems such as a reverse phenomenon. Therefore, it is possible to appropriately determine the velocity regardless of the performance method at the time of performance and the key pressing strength. In addition, key speed data used to determine velocity can be extracted by simply excluding the maximum value data and minimum value data. Compared with the case where the above process is performed, the velocity can be determined by a very simple arithmetic process.

  The invention according to claim 2 is a velocity determining device for a keyboard instrument that determines the velocity in order to control the volume according to the key-pressing strength of the rotatable key, and is different from each other within the key rotation range. In three or more predetermined sections, the key speed data detecting means for detecting the key speed data representing the key rotation speed, and the variation representing the degree of variation of the key speed data based on the plurality of detected key speed data A variation parameter calculating means for calculating a parameter, and an excluded data number determining means for determining the number of key speed data to be excluded from a plurality of detected key speed data as an excluded data number according to the calculated variation parameter; Velocity determining means for determining the velocity based on the remaining key speed data excluding the key speed data corresponding to the number of excluded data. It is characterized in.

  According to the velocity determining device for a keyboard instrument, the variation parameter calculating means calculates a variation parameter representing the variation degree of the key speed data based on the detected plurality of key speed data. The excluded data number determination means determines the number of key speed data to be excluded from the detected plurality of key speed data as the excluded data number according to the calculated variation parameter. For this reason, when variations occur in the key speed at the time of key depression, such as when a gradual step occurs when the key is depressed, the number of key velocity data corresponding to the degree of variation is excluded. It is possible to eliminate the influence due to the variation of the. The velocity determining means determines the velocity based on the remaining key speed data excluding the determined number of excluded data key speed data. As described above, when determining the velocity, the key speed data of the number of excluded data corresponding to the degree of variation of the key speed data is excluded, so that the influence due to the gradual speed can be removed and problems such as the reverse phenomenon can be prevented. . Therefore, it is possible to appropriately determine the velocity regardless of the performance method at the time of performance and the key pressing strength. In addition, the key speed data used for determining the velocity can be extracted simply by excluding the key speed data of the number of excluded data according to the degree of variation. Velocity can be determined.

  According to a third aspect of the present invention, in the velocity determining apparatus for a keyboard instrument according to the second aspect, the excluded data number determining means increases the number of excluded data as the variation degree of the plurality of key speed data represented by the variation parameter increases. Is determined to be a larger value.

  According to this configuration, as the degree of variation in key speed data at the time of key depression increases, more key speed data is excluded. Therefore, even when the degree of variation in key speed data is large, key speed data that favorably represents velocity. Velocity can be determined appropriately using only

  According to a fourth aspect of the present invention, in the velocity determining apparatus for a keyboard instrument according to the third aspect, the number of excluded data determined by the excluded data number determining means is an even number, and is detected according to the determined number of excluded data. It further comprises an excluded data determination means that prioritizes the maximum value data and the minimum value data of the key speed data and determines the key speed data to be excluded.

  According to this configuration, the number of excluded data is determined to be an even number, and the maximum value data and the minimum value data of the detected key speed data are preferentially excluded according to the determined number of excluded data. That is, when the number of excluded data is 2, for example, the maximum value data and the minimum value data are excluded, and when it is 4, the maximum value data, the second largest key rate data, the minimum value data, and the second smallest data Exclude key rate data. As a result, it is possible to reliably exclude excessive or excessive key speed data. Furthermore, since the even number of key speed data is excluded, the maximum and minimum data of the key speed data can be excluded in a well-balanced manner, and the velocity can be appropriately determined using the non-biased key speed data.

  According to a fifth aspect of the present invention, in the velocity determining apparatus for a keyboard instrument according to any one of the second to fourth aspects, the variation parameter is a standard deviation of a plurality of key speed data.

  According to this configuration, since the standard deviation of a plurality of key speed data is used as a variation parameter, the degree of variation of the key speed data can be appropriately evaluated, and accordingly, the number of excluded data can be appropriately determined based on this.

  According to a sixth aspect of the present invention, in the keyboard instrument velocity determining apparatus according to any of the second to fourth aspects, the variation parameter is a square of a standard deviation of a plurality of key speed data.

  In general, the calculation of the standard deviation requires the calculation of the square root. However, according to this configuration, the square of the standard deviation of a plurality of key speed data is used as the variation parameter, so the calculation of the square root becomes unnecessary. The processing time can be shortened.

  Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the drawings. 1 and 2 show an upright type mute piano 2 (keyboard instrument) to which a velocity determining apparatus 1 according to an embodiment of the present invention is applied. In the following description, when the mute piano 2 is viewed from the performer, the front side (right side in FIG. 1) is “front”, the back side (left side in FIG. 1) is “rear”, and the left side and right side are respectively The description will be given as “left” and “right”. As shown in FIG. 1, the mute piano 2 is placed on a shelf board 3, a plurality of keys 4 mounted on the shelf board 3 and composed of a white key 4a and a black key 4b (only one is shown), and a key 4 A hammer 5 for striking the string 15, an action 6 provided above the rear part of the key 4, and a key position sensor 16 (key speed data detecting means) for detecting key pressing information of the key 4. And a musical tone generator 19 (see FIG. 3) for electronically generating performance sounds. In the mute piano 2, the performance mode includes a normal performance mode in which an acoustic performance sound is generated by striking with the hammer 5, and a key-pressing information detected by the key position sensor 16 while blocking the striking with the hammer 5. In response, the musical tone generator 19 switches to a mute performance mode in which a performance sound is generated.

  The key 4 is rotatably supported by a balance pin 14 erected from a balance rail 3a provided on the shelf board 3 through a balance pin hole (not shown) formed in the center thereof. .

  The action 6 is for rotating the hammer 5 when the key 4 is pressed, and a wippen 8 extending in the front-rear direction and placed on the rear of each key 4 via a capstan screw 10; A jack 9 and the like that are rotatably attached to the whippen 8 are provided. Each whippen 8 is rotatably supported by the center rail 11 at the rear end. The jack 9 is formed in an L shape from a push-up portion 9a extending in the vertical direction and an engaging portion 9b extending substantially perpendicularly forward from the lower end portion thereof. It is attached. A damper 12 is rotatably attached to the rear end portion of the center rail 11.

  On the other hand, the hammer 5 includes a bat 5a, a hammer shank 5b extending upward from the bat 5a, a hammer head 5c attached to the upper end of the hammer shank 5b, and the like. 11 is rotatably attached. In the key release state shown in FIG. 1, the tip of the push-up portion 9 a of the jack 9 is engaged with the bat 5 a, the hammer shank 5 b is in contact with the hammer rail 13 at an angle, and the hammer head 5 c is opposed to the string 15. ing.

  A stopper 7 is provided between the hammer 5 and the string 15. This stopper 7 is for preventing the string 15 from being hit by the hammer 5 in the mute performance mode, and is composed of a main body portion 7a and a cushion (not shown) attached to the tip thereof. . The stopper 7 is rotatably supported by a fulcrum 7b at one end of the main body 7a, and is driven by a motor (not shown). The stopper 7 extends in the vertical direction in the normal performance mode and is driven to a retracted position (solid line position in FIG. 1) retracted from the rotation range of the hammer shank 5b of the hammer 5 while in the forward and backward direction in the mute performance mode. And is driven to an entry position (dotted line position in FIG. 1) that has entered the rotation range of the hammer shank 5b. This motor is driven by a drive signal from a CPU 23 described later.

  With the above configuration, in the normal performance mode, the stopper 7 is driven to the retracted position, and when the key 4 is pressed in this state, the key 4 rotates around the balance pin 14 in the clockwise direction in FIG. With this rotation, the whippen 8 rotates counterclockwise. As the whippen 8 rotates, the jack 9 moves upward together with the whippen 8, and the push-up portion 9a pushes up the bat 5a, whereby the hammer 5 rotates counterclockwise and the hammer head 5c is turned into a string. Strike 15 On the other hand, in the mute performance mode, the stopper 7 is driven to the entry position. When the key 4 is pressed, the hammer 5 rotates counterclockwise as in the normal performance mode. In the middle of this rotation, immediately before the hammer head 5c hits the string 15, the hammer shank 5b comes into contact with the stopper 7 located at the entry position, so that further rotation of the hammer 5 is prevented. 15 strings are blocked. At this time, the key pressing information of the key 4 is detected by the key position sensor 16, and a musical tone is generated by the musical tone generator 19 according to the detected key pressing information.

  As shown in FIG. 2, the key position sensor 16 includes a shutter 17 and first and second sensor elements 21 and 22. The shutter 17 is provided so as to protrude downwardly in front of the balance pin 14 on the lower surface of the key 4. The shutter 17 is configured by a substantially rectangular flat plate. In the left half portion 17L and the right half portion 17R, five slits 18L1 to 18L5 and 18R1 to 18R5 extending in the left-right direction are provided in the vertical direction in order from the bottom. Are formed at regular intervals. The height H of each slit 18 is equal to the distance G between the slits 18, 18, that is, the distance between the upper end of the lower slit 18 and the lower end of the upper slit 18. Further, the slits 18L1 to 18L5 of the left half portion 17L and the slits 18R1 to 18R5 of the right half portion 17R are arranged in a staggered manner, specifically, the height of each slit 18L of the left half portion 17L. It arrange | positions so that the lower end of each slit 18R corresponding to a center and the right half part 17R may correspond. Further, the lower end portion of the left half portion 17L of the shutter 17 protrudes downward by a length ½ of the height of the slit 18 from the lower end of the right half portion 17R, that is, the left half portion 17L and the right portion. The height of the lower end portion of the half portion 17R is also equal to the interval G between the slits 18 and 18.

  The first and second sensor elements 21 and 22 are arranged at the same height within the rotation range of the key 4 below the left half 17L and the right half 17R of the shutter 17, respectively. A pair of light emitting elements and light receiving elements (both not shown) are respectively configured. These light emitting elements and light receiving elements are arranged at the same height and at a predetermined interval on both sides of the movement path of the shutter 17. The light emitting element emits light from its light emitting surface (not shown) toward the light receiving element. On the other hand, the light receiving element receives this light at its light receiving surface (not shown) and converts the received light into an electrical signal. These electrical signals are output to the CPU 23 via the keyboard scanning circuit 20 as first and second detection signals S1, S2 corresponding to the rotational position of the key 4, as shown in FIG. Specifically, as the shutter 17 is lowered or raised in response to the key 4 being pressed or released, other than the slit 18 of the shutter 17 on the optical path connecting the light emitting surface of the light emitting element and the light receiving surface of the light receiving element. The light receiving element outputs an H level signal when the light on the light receiving surface is blocked due to the position of. On the other hand, when the slit 18 of the shutter 17 is positioned on the optical path, the light receiving element outputs an L level signal when the light reaches the light receiving surface.

  FIG. 4 shows a timing chart of the first and second detection signals S1 and S2 when the key 4 is pressed at a constant speed over the entire rotation range. First, in the key release state shown in FIG. 2, the first and second detection signals S1 and S2 are both at the L level when the light reaches the light receiving surfaces of the sensor elements 21 and 22, respectively. Next, as the key 4 is depressed, the shutter 17 is lowered, and the first measurement point on the left side (see FIG. 2) corresponding to the lower end of the left half portion 17L reaches the optical path of the first sensor element 21. Sometimes, the light to the light receiving element is blocked, so that the first detection signal S1 rises from the L level to the H level (timing t1). Next, when the right first ′ measurement point corresponding to the lower end of the right half portion 17R of the shutter 17 reaches the optical path of the second sensor element 22, light to the light receiving element is blocked. 2 The detection signal S2 rises from the L level to the H level (t1 ′).

  When the shutter 17 is further lowered, when the second measurement point corresponding to the lower end of the lowermost slit 18L1 of the left half 17L reaches the optical path of the first sensor element 21, the light reaches the light receiving element. The first detection signal S1 falls from the H level to the L level (t2). Next, when the second ′ measurement point corresponding to the lower end of the lowermost slit 18R1 of the right half portion 17R reaches the optical path of the second sensor element 22, the light reaches the light receiving element, and the second detection signal S2 falls from the H level to the L level (t2 ′). Thereafter, until the key 4 reaches the lower limit position of the rotation range (corresponding to the dotted line positions of the first and second sensor elements 21 and 22 in FIG. 2), the first and second sensor elements 21 and 22 as described above The blocking and non-blocking of the optical path are repeated in the same manner, whereby the first and second detection signals S1 and S2 become pulse signals that alternately repeat the H level or the L level.

  In the present embodiment, rise or fall time differences Δt1 to Δt10 between the first and second detection signals S1 and S2 are obtained as passage times of the first to tenth measurement sections, and further, based on them, each measurement is performed. Calculate the key speed of the section. These first to tenth measurement intervals are between the first measurement point and the first 'measurement point, between the second measurement point and the second' measurement point, ..., and the tenth measurement point and the tenth measurement point. 'Equivalent between the measurement points. Further, due to the configuration of the shutter 17 described above, the lengths of the first to tenth measurement sections are equal to each other and are ½ of the height H of the slit 18.

  As shown in FIG. 10, when the key is released, the first and second detection signals S1 and S2 are pulse signals that alternately repeat H level or L level in the reverse order. Therefore, as is apparent from the comparison between FIG. 4 and FIG. 10, when the key 4 is lowered, the second detection signal S2 rises following the rise of the first detection signal S1, and the rise of the first detection signal S1. Following the fall, the second detection signal S2 falls. On the other hand, when the key 4 is raised, these relations are reversed, the first detection signal S1 rises following the rise of the second detection signal S2, and the second detection signal S2 follows the fall. 1 detection signal S1 falls. Therefore, by monitoring the rising order or the falling order between the first and second detection signals S1 and S2, it is possible to easily identify whether the key 4 is in the falling or rising state. .

  As described above, the tone generator 19 generates a tone in the mute performance mode. As shown in FIG. 3, the keyboard scan circuit 20, CPU 23, ROM 24, RAM 25, tone generator circuit 26, waveform memory 27, DSP 28 are provided. , A D / A converter 29 and a speaker 30. The keyboard scan circuit 20 receives the first and second key number information for identifying the key 4 that is turned on or off, and the on / off information of the key 4 based on the first and second detection signals S1 and S2 of the key position sensor 16. Together with the second detection signals S1 and S2, it is output to the CPU 23 as key press information data of the key 4. In addition to the control program executed by the CPU 23, the ROM 24 stores fixed data for control for controlling the volume and the like. The RAM 25 temporarily stores status information indicating the operation state in the mute performance mode and is also used as a work area for the CPU 23.

  The tone generator circuit 26 reads the musical sound waveform data and envelope data from the waveform memory 27 in accordance with the control signal from the CPU 23, and adds the envelope data to the read musical sound waveform data, thereby generating a musical sound signal MS as an original sound. The DSP 28 adds a predetermined acoustic effect to the musical sound signal MS generated by the sound source circuit 26. The D / A converter 29 converts the musical sound signal MS to which the sound effect has been added by the DSP 28 from a digital signal into an analog signal, and then the analog signal is output from the speaker 30 via a power amplifier (not shown). Played and emitted as a musical sound.

  The CPU 23 (key speed data exclusion means, variation parameter calculation means, exclusion data number determination means, exclusion data determination means, and velocity determination means) is for comprehensively controlling the operation of each part in the mute performance mode. The CPU 23 determines the velocity for controlling the sound volume according to the key speed according to the control program stored in the ROM 24 according to the first and second detection signals S1, S2 from the key position sensor 16.

  FIG. 5 is a flowchart showing the velocity determination process executed by the CPU 23. In this process, when the key 4 is pressed, first, in step 1 (illustrated as “S1”, the same applies hereinafter), based on the first and second detection signals S1, S2 from the key position sensor 16, The passage times Δt1 to Δt10 of the first to tenth measurement intervals are calculated.

  Next, the key speeds V1 to V10 (key speed data) of each measurement section are calculated by dividing the length (H / 2) of the first to tenth measurement sections by the passage times Δt1 to Δt10 (step 2). . Next, the calculated key speeds V1 to V10 are compared, and the maximum value Vmax (maximum value data) and the minimum value Vmin (minimum value data) are specified (step 3). Next, the maximum value Vmax and the minimum value Vmin are excluded from the key speeds V1 to V10, the average value Vavr of the remaining key speeds is calculated (step 4), and this average value Vavr is set as the velocity V (step 5). This process is terminated.

  FIG. 6 shows an example of the relationship between the time t from the start of key pressing and the moving distance x of the key 4 when a gradual step occurs while the key 4 is being pressed. As shown in the figure, in this example, first, the key speed is substantially constant in the first to fifth measurement sections, and therefore, the passage times Δt1 to Δt5 and the key speeds V1 to V5 are also substantially constant. Value. In addition, a gradual stage occurs in the vicinity of the sixth measurement interval, and as a result, the key speed decreases. As a result, it takes time to pass through the sixth measurement interval, and the passage time Δt6 increases. The key speed V6 calculated based on this is minimized. Thereafter, as the gradual stage ends, the key speed increases rapidly in the vicinity of the seventh measurement interval, and therefore the passing time Δt7 of the seventh measurement interval becomes very small, and the key speed V7 is maximized. Become. Further, the key speed decreases in the vicinity of the eighth measurement section, and thereafter becomes substantially constant. The transit times Δt8 to Δt10 and the key speeds V8 to V10 in the eighth to tenth measurement sections are the first to fifth. The value is almost the same as the measurement interval.

  On the other hand, in the velocity determination process described above, when determining the velocity V, the key speed V6 of the sixth measurement section is specified as the minimum value Vmin from the key speeds V1 to V10, and the key speed V7 of the seventh measurement section is determined. Are specified as the maximum value Vmax, and they are excluded from the velocity calculation, so that the influence of the gradual stage can be removed, thereby preventing problems such as a reverse phenomenon. Therefore, the velocity V can be appropriately determined regardless of the performance method and the key pressing strength at the time of performance. Further, since the key speeds V1 to V10 used for determining the velocity V can be extracted simply by excluding the maximum value Vmax and the minimum value Vmin, the type of key operation and the characteristic section identification as in the conventional velocity determining device described above are specified. The velocity V can be determined by a very simple calculation process as compared with the case where such processes are performed.

  Next, the velocity determination process according to the second embodiment of the present invention will be described with reference to FIG. In this process, similarly to the process according to the first embodiment shown in FIG. 5, first, the passage times Δt1 to Δt10 are calculated based on the first and second detection signals S1 and S2 (step 11), and the passage time. In accordance with Δt1 to Δ10, key velocities V1 to V10 of each measurement section are calculated (step 12). Next, the standard deviation S (variation parameter) of the calculated key speeds V1 to V10 is calculated by the following equation (1) (step 13).

次いで、算出した標準偏差Ｓに応じ、図８に示すテーブルを検索することによって、鍵速度Ｖ１〜Ｖ１０から除外すべき鍵速度のデータ数（以下「除外データ数」という）Ｎを決定する（ステップ１４）。図８のテーブルでは、除外データ数Ｎは、標準偏差Ｓが第１所定値Ｓｒｅｆ１未満のときに値０に、標準偏差Ｓが第１所定値Ｓｒｅｆ１以上かつ第２所定値Ｓｒｅｆ２（＞Ｓｒｅｆ１）未満のときに値２に、標準偏差Ｓが第２所定値Ｓｒｅｆ２以上のときに値４に、それぞれ設定されている。このように、標準偏差Ｓが大きいほど、すなわち鍵速度Ｖ１〜Ｖ１０のばらつき度合が大きいほど、除外データ数Ｎがより大きな値に決定される。

Next, by searching the table shown in FIG. 8 according to the calculated standard deviation S, the number N of key speed data (hereinafter referred to as “excluded data number”) N to be excluded from the key speeds V1 to V10 is determined (step). 14). In the table of FIG. 8, the number of excluded data N is 0 when the standard deviation S is less than the first predetermined value Sref1, and the standard deviation S is greater than or equal to the first predetermined value Sref1 and less than the second predetermined value Sref2 (> Sref1). Is set to a value of 2, and a standard deviation S is set to a value of 4 when the standard deviation S is greater than or equal to a second predetermined value Sref2. Thus, the larger the standard deviation S, that is, the greater the degree of variation in the key speeds V1 to V10, the larger the number of excluded data N is determined.

  Next, it is determined whether or not the calculated number of excluded data N is 0 (step 15). When the determined result is NO, the excluded data to be excluded from the key speed data is determined according to the number of excluded data N. (Step 16). In this case, when the number of excluded data N is 2, the maximum value Vmax and the minimum value Vmin are excluded from the key speeds V1 to V10, and when the number of excluded data N is 4, the maximum of the key speeds V1 to V10 is excluded. Exclude the value Vmax and the second largest key speed, and the minimum value Vmin and the second smallest key speed. Thereby, it is possible to reliably exclude an excessive or excessive key speed.

  Next, the average value Vavr of the remaining key speed data is calculated (step 17), this average value Vavr is set as the velocity V (step 18), and this process is terminated. On the other hand, if the determination result in step 15 is YES and the number of excluded data N = 0, the process proceeds to step 17 to calculate the average value Vavr using all the key speeds V1 to V10.

  As described above, according to the present embodiment, when the velocity V is determined, the standard deviation S of the key speeds V1 to V10 is calculated. As the standard deviation S is larger, that is, the degree of variation in the key speed is larger, Since more key speed data is excluded, even when the degree of variation in the key speed is large, the velocity V can be appropriately determined using only the key speed data that favorably represents the velocity. Therefore, as in the first embodiment, it is possible to eliminate the influence of slow grading, etc., and to prevent problems such as the reverse phenomenon, so that the velocity V can be appropriately set regardless of the performance method and key depression strength at the time of performance. Can be determined. In addition, since the key speed data used for determining the velocity V can be extracted simply by excluding the key speed data of the number N of excluded data corresponding to the degree of variation, the calculation is simpler than the conventional velocity determining apparatus described above. The velocity V can be determined by processing. Further, as the standard deviation S is larger, more key speed data is excluded, so even when the degree of variation of the key speed data is large, the velocity V is appropriately determined using only the key speed data that represents the velocity well. can do. Moreover, since the standard deviation S is used, the degree of variation of the key speeds V1 to V10 can be appropriately evaluated, and accordingly, the number of excluded data N can be appropriately determined based on the degree of variation. Furthermore, since the even number of key speed data is excluded, the maximum side and the minimum side of the key speed data can be excluded in a well-balanced manner, and the velocity V can be appropriately determined using the non-biased key speed data.

Next, the velocity determination process according to the third embodiment of the present invention will be described with reference to FIG. This process differs from the second embodiment described above in that the square S ² is used in place of the standard deviation S as a parameter representing the degree of variation in key speed. That is, in this process, as in the process according to the second embodiment shown in FIG. 7, first, the passage times Δt1 to Δt10 are calculated based on the first and second detection signals S1 and S2 (step 21). The key speeds V1 to V10 are calculated according to the passage times Δt1 to Δt10 (step 22). Next, the square S ² of the standard deviation of the calculated key speeds V1 to V10 is calculated by the following equation (2) (step 23).

次いで、算出した標準偏差の自乗Ｓ²に応じ、テーブル（図示せず）を検索することによって、除外データ数Ｎを決定する（ステップ２４）。このテーブルでは、第２実施形態と同様、標準偏差の自乗Ｓ²が大きいほど、除外データ数Ｎは大きな値に設定されている。

Next, the number N of excluded data is determined by searching a table (not shown) according to the calculated square of the standard deviation S ² (step 24). In this table, as in the second embodiment, the larger the square S ² standard deviations, excluded data number N is set to a large value.

  Next, as in the second embodiment, it is determined whether or not the calculated number N of excluded data is 0 (step 25). When the determination result is NO, the exclusion data of the key speed data is determined according to the number N of excluded data (step 26), the average value Vavr of the remaining key speed data is calculated (step 27), and this average value Vavr Is set as velocity V (step 28), and this process is terminated. On the other hand, if the determination result in step 25 is YES and the number of excluded data N = 0, the process proceeds to step 27, where the average value Vavr is calculated using all the key speeds V1 to V10.

As described above, according to this embodiment, since use of the square S ² standard deviations as variation parameters, compared to the standard deviation S using the second embodiment eliminates the need for calculation of the square root, the load of calculation And processing time can be shortened.

In addition, this invention can be implemented in various aspects, without being limited to the described embodiment. For example, in the embodiment, the key speeds V1 to V10 are used as the key speed data representing the rotation speed of the key 4. However, the present invention is not limited to this, and for example, the passage times Δt1 to Δt10 may be used directly. This is because the passage times Δt1 to Δt10 are inversely proportional to the key speeds V1 to V10 because the first to tenth measurement intervals are set to have the same length as described above. Furthermore, in the embodiment, a combination of the shutter 17 and the first and second sensor elements 21 and 22 is used as a sensor for detecting the key speeds V1 to V10, but other appropriate types of sensors are used. For example, a sensor of a type whose capacitance or resistance value changes according to the amount of displacement of the key 4 may be used. In the embodiment, the key speed is detected in the first to tenth measurement sections, that is, ten sections. However, the number of sections for detecting the key speed is not limited to this, and may be three or more different from each other. If desired, it can be set arbitrarily. Further, in the second and third embodiments, the standard deviation S and the square of the standard deviation S ² are used as the variation parameters indicating the variation degree of the key speed data, but the present invention is not limited to this, and other appropriate parameters. May be used.

  In addition, the embodiment is an example in which the present invention is applied to a mute piano. However, the present invention is not limited to this, and other types of keyboard instruments such as an automatic piano having a hammer and an electronic piano, as well as an electronic piano having no hammer. It is also possible to apply to. In addition, it is possible to appropriately change details within the scope of the gist of the present invention.

It is a figure which shows schematic structure of the velocity determination apparatus of this invention, and the muffling piano to which this is applied. It is the elements on larger scale of FIG. It is a block diagram of the velocity determination apparatus of FIG. The timing chart of the 1st and 2nd detection signal at the time of key depression is shown. It is a flowchart which shows the control processing performed with CPU of FIG. It is a figure which shows an example of the relationship between the time from the start time of a key press, and the movement distance of a key. It is a flowchart which shows the control processing by 2nd Embodiment of this invention. It is a figure which shows an example of the table of the number of exclusion data used by the process of FIG. It is a flowchart which shows the control processing by 3rd Embodiment of this invention. The timing chart of the 1st and 2nd detection signal at the time of key release is shown.

Explanation of symbols

1 Velocity determination device
2 Silent piano (keyboard instrument)
4 key 16 key position sensor (key speed data detection means)
20 keyboard scan circuit 23 CPU (key speed data excluding means, variation parameter calculating means,
Exclusion data number determination means, exclusion data determination means and
City determination means)
24 ROM
V1 to V10 Key speed (key speed data)
Vmax maximum value (maximum value data)
Vmin Minimum value (minimum value data)
S Standard deviation (variation parameter)
S ² Square of standard deviation (variation parameter)
N Number of excluded data
V velocity

Claims (6)

A velocity determining device for a keyboard instrument that determines a velocity in order to control the volume according to the key pressing strength of a rotatable key,
Key speed data detection means for detecting each of the key rotation data representing the key rotation speed in three or more different predetermined sections within the key rotation range;
Key speed data excluding means for excluding the maximum value data and the minimum value data from the plurality of detected key speed data;
Velocity determining means for determining the velocity based on the remaining key speed data excluding the maximum value data and the minimum value data;
A velocity determining device for a keyboard instrument, comprising: A velocity determining device for a keyboard instrument that determines a velocity in order to control the volume according to the key pressing strength of a rotatable key,
Key speed data detection means for detecting each of the key rotation data representing the key rotation speed in three or more different predetermined sections within the key rotation range;
Variation parameter calculation means for calculating a variation parameter representing the variation degree of the key speed data based on the detected plurality of key speed data;
Excluded data number determination means for determining, as the excluded data number, the number of key speed data to be excluded from the detected plurality of key speed data according to the calculated variation parameter;
Velocity determining means for determining the velocity based on the remaining key speed data excluding the determined number of excluded key speed data;
A velocity determining device for a keyboard instrument, comprising:   The said exclusion data number determination means determines the said exclusion data number to a larger value, so that the dispersion | variation degree of several key speed data represented by the said dispersion | variation parameter is large. Velocity determination device for keyboard instruments. The number of excluded data determined by the number of excluded data determining means is an even number;
According to the determined number of excluded data, it further comprises an excluded data determining means that prioritizes the maximum value data and the minimum value data of the detected key speed data and determines the key speed data to be excluded. The velocity determining apparatus for a keyboard instrument according to claim 3.   5. The velocity determining apparatus for a keyboard instrument according to claim 2, wherein the variation parameter is a standard deviation of the plurality of key speed data.   5. The velocity determining apparatus for a keyboard instrument according to claim 2, wherein the variation parameter is a square of a standard deviation of the plurality of key speed data.

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