JPH0624878Y2 - Electronic stringed instrument - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION <Industrial Application Field> The present invention relates to an electronic stringed instrument, and more particularly to an electronic stringed instrument that determines a pitch designated by a performer by scanning an ultrasonic signal.

<Prior Art> Generally, in an electronic stringed instrument, the position of the fret with which the string pressed by the player is in contact is discriminated, and the pitch of the musical tone to be generated is specified based on the discrimination result. The timing is detected to generate a musical tone of the specified pitch.

In the discrimination of the fret position in the sounding process of such an electronic stringed instrument, since the strings vibrate at a period corresponding to the string length at the time of turning, the string vibration is converted into an electric signal of a waveform similar to this by an electromagnetic pickup, and the It was done based on the peak spacing of the waveform.

However, in the case of converting the string vibration based on the above-mentioned string into an electric signal, it took a long time from the string to the generation of a musical sound, which gave an unnatural impression to the performer. In Japanese Patent Application No. 240138 of 1985 (hereinafter referred to as a prior application), an electronic stringed instrument for discriminating the fret position based on ultrasonic scanning was proposed. In the electronic stringed instrument disclosed in this prior application, an electric signal is converted into an ultrasonic signal by a piezoelectric element, the ultrasonic signal is transmitted to the string, and the ultrasonic signal is transmitted and reflected by a fret in contact with the string. The fret position was determined based on the time required to receive the echo.

<Problems to be solved by the invention> However, in the electronic stringed instrument according to such a prior application, as described above, the fret position is determined based on the time required from the transmission of the ultrasonic signal to the reception of the echo of the ultrasonic signal. Therefore, the echo reflected by the fret needs to be discriminable by the piezoelectric element.

However, in general, the ultrasonic signal travels in all directions if the propagation medium is present, and when the propagation medium is in contact with substances having different densities, it is reflected by the substances to generate an echo. The ultrasonic wave generated by the piezoelectric element also propagates through the strings not only in the fret direction but also in the opposite tail piece direction, and echo is also generated by this tail piece. Since the echo reflected by the tail piece is also converted into an electric signal by the piezoelectric element, there is a possibility that the fret position may be erroneously determined if the echo and the echo reflected by the fret cannot be distinguished.

Therefore, an object of the present invention is to provide an electronic stringed instrument capable of accurately determining the fret position by removing unwanted echoes.

<Means for Solving the Problems> The present invention relates to an electronic string instrument, which is a string that is stretched on the body of a musical instrument and has one end locked to a tail piece, and an electric signal that is converted into an ultrasonic signal. Piezoelectric conversion means provided on the main body of the musical instrument so as to supply a signal to the strings, and a vibration isolator that contacts the strings between the piezoelectric conversion means and the tail piece and attenuates the ultrasonic signals Is the gist.

<Operation and Effect> In the electronic stringed instrument according to the above configuration, when the ultrasonic signal is generated based on the electric signal supplied by the piezoelectric conversion means,
The ultrasonic signal is transmitted from the piezoelectric converting means to the string and propagates in the fret direction and the tail piece direction, respectively.
Then, on the one hand, this ultrasonic signal is reflected by the frets to generate an echo, and propagates again through the string toward the piezoelectric conversion means. On the other hand, since the ultrasonic signal propagating toward the tailpiece is attenuated according to the attenuation characteristic of the vibration isolator, no echo is generated. As a result, the electric signal generated by the piezoelectric conversion means includes only the component of the echo generated by the frets, and the position of the fret that generated the echo can be easily determined based on the electric signal.

<Embodiment> An embodiment of the present invention will be described below with reference to the drawings. First
FIG. 2 is a side view of an electronic stringed instrument showing an embodiment of the present invention,
The drawing is an enlarged side view showing the tail piece portion, and this embodiment is an application of the present invention to a six-string guitar.

In these figures, reference numeral 1 denotes a musical instrument body, and between the string winding 3 and the tailpiece 5 of the musical instrument body 1, six strings 7A, 7B, ... Is stretched over. 7 strings on the neck of the instrument body 1
N frets 19, 21, at approximately right angles to A ...
.. are planted, and the frets 19, 21, ... are 6
It is arranged below the strings 7A, ... Further, six electromagnetic pickups 23A, 23B, ... Are provided on the instrument body 1 (body) on the tailpiece 5 side.
And the bridge assembly 35 are fixed. These electromagnetic pickups 23A ... Are provided in correspondence with the respective strings 7A ..., and detect low-frequency vibrations that occur in the strings 7A. Then, the string signal ON is sent to the tone generator 37.

On the other hand, the bridge assembly 35 supports six ceramic piezoelectric elements 39A, 39B, ... As piezoelectric conversion means, and these piezoelectric elements 39A ... Are intermittently fed from the fret position discriminating circuit 51. An ultrasonic wave signal of about 450 KHz is generated based on the electric pulse signal SCAN supplied to, and the ultrasonic wave signal is transmitted to each corresponding string 7A. The ultrasonic signals transmitted to the strings 7A ...
.., and when the strings 7A ... are pressed toward the neck and are in contact with any of the frets 19, 21, ..., They are reflected by the frets 19, 21 ,. Generate. This echo is again piezoelectric element 39A
.. propagating through the strings 7A ... toward the piezoelectric element 39A.
Is converted into an electric signal DET having a waveform similar to that of the echo.

The fret position determination circuit 51 uses the electric pulse signal SC
Frets 19 and 21, which are in contact with the strings 7A ... Based on the time from the sending of the AN to the reception of the electric signal DET.
. Is discriminated, and a pitch signal representing the pitch corresponding to the frets 19, 21, ... Contacting the strings 7A ... Is supplied to the tone generator 37 based on the discrimination result. As a result, the tone generator 37 forms a musical tone signal based on the supplied pitch signal, and when the chord signal ON is supplied,
The musical tone signal is sent to the sound system 53 to generate a musical tone having a predetermined pitch.

Next, FIG. 2 shows the vibration isolator 145 and the bridge assembly 35 arranged on the tail piece 5 side of the musical instrument body 1.

The bridge assembly 35 has a bridge base 105 that is supported by a pair of studs 101 that are planted in the musical instrument body 1. A nut 111 is screwed to each of the pair of studs 101, and the bridge base 10
The nut 5 is restricted from moving downward in FIG. 2 by these nuts 111, and its height position can be adjusted.

Supports 127 (holders) are fitted into the bridge base 105, and these supports 127 are the piezoelectric elements 3 described above.
Holds 9A, etc. The upper left corner of the support 127 in FIG. 2 is chamfered, so that the strings 7A and the like extending from the piezoelectric elements 39A and the like toward the string winding 3 may have the piezoelectric elements 39A and the like protruding from the instrument body 1. Without support 1
Do not touch 27 etc.

On the other hand, projections 141 made of an elastic body are formed on the upper right end surface of the support body 127 in FIG.
1 is in contact with each string 7A and the like.

Further, a vibration isolator 145 is provided upright on the upper surface of the musical instrument body 1 between the piezoelectric element 39A and the like and the tail piece 5 by adhesion, and the upper surface of the vibration isolator 145 is inclined as shown in the figure. It is formed and is always in contact with the strings 7A and the like. As a result, the ultrasonic signal transmitted from the piezoelectric element 39A or the like to the string 7A or the like also propagates to the tail piece 5 side of the string 7A or the like, but is attenuated by these protrusions 141 and the vibration isolator 145 to generate a sufficient echo. It does not occur.

Next, materials of the protrusion 141 and the vibration isolator 145 will be described. The protrusion 141 and the vibration isolator 145 need only be capable of attenuating mechanical vibrations of approximately 450 KHz, and in order to do so, it is necessary that the attenuation coefficient be a predetermined value or more. In this embodiment, the hardness is JIS 30 to 70 degrees. Uses chloroprene rubber.

Next, the operation of the above embodiment will be described.

During the performance, the fret position discriminating circuit 51 outputs the electric pulse signal S
CAN is intermittently sent to each piezoelectric element 39A,
Each piezoelectric element 39A or the like generates an ultrasonic signal based on the electric pulse signal SCAN. The ultrasonic signals generated by the piezoelectric elements 39A and the like are transmitted to the strings 7A and the like as described above, and the frets 19, 21 ...
It is reflected by and produces an echo. On the other hand, the ultrasonic signal propagates through the strings 7A and the like toward the tailpiece 5 side, but the ultrasonic signal is attenuated by the projection 141 and the vibration isolator 145 in the propagation process, and the tailpiece 5 It becomes difficult to reach to. Further, even if a part of the echo reaches, the echo generated by being reflected by the tailpiece 5 is further attenuated by the vibration isolator 145 and the projection 141 in the propagation process thereof, so that the piezoelectric element 39 is again provided.
It never reaches A, etc., and even if it reaches it, it is significantly attenuated. As a result, the fret 19,
Electric signals D generated by the echoes generated at 21, ...
The amplitude of ET becomes significantly larger than the amplitude of the electric signal DET generated by the echo generated in the tail piece 5 (or the echo is not generated in the tail piece 5), and the fret position determination circuit 51 determines the fret based on this amplitude difference. 19, 2
It is possible to easily separate the echoes generated by being reflected by 1, ...

Next, FIGS. 3 and 4 show other embodiments of the present invention.

FIG. 3 shows that the tail piece 5 has a horizontal extending portion 5A protruding toward the piezoelectric element 39A side.
A vibration isolator 155 is provided on the upper surface in a protruding manner. According to this, the tail piece 5 and the vibration isolator 155 can be integrated, and the manufacture thereof is facilitated.

Further, FIG. 4 shows that the vibration isolator 165 is formed of a cylindrical rubber bush, and the rubber bush 165 is fitted into the hole 5B of the tail piece 5. The strings 7A and the like are inserted into the rubber bush 165, and the string ball ends 7a and the like at one end thereof are the rubber bush 16 and the like.
It is locked to 5. Therefore, according to this embodiment, when the tail piece 5 and the vibration isolator 165 are integrated, the size of the tail piece 5 and the vibration isolator 165 can be further reduced, and the instrument body 1 can be easily assembled.

In addition, also in each of these embodiments, other configurations and operations are similar to those of the above-mentioned embodiments.

Further, in each of the above embodiments, the piezoelectric element 39A or the like is directly connected to the string 7A
, The ultrasonic signal can be efficiently transmitted to the strings 7A and the like. In addition, when another member is interposed between the piezoelectric element 39A and the like and the string 7A and the like, it is necessary to make the mass as small as possible. I can't shake,
In particular, it is difficult to convert the echo reflected by the frets 19, 21, ... To the electric signal DET.

Further, in each of the above-described embodiments, since the protrusion 141 made of rubber or the like and the vibration isolator 145, 155, 165 are necessarily interposed between each piezoelectric element 39A or the like and the bridge base 105, any piezoelectric element 39A or the like The ultrasonic signal generated in the above is sufficiently attenuated before reaching other piezoelectric elements 39A,
The positions of the frets 19, 21, ... Are not mistakenly determined based on the ultrasonic signal generated by the adjacent piezoelectric element 39A or the like.

[Brief description of drawings]

FIG. 1 is a side view of an electronic stringed instrument showing an embodiment of the present invention, FIG. 2 is a sectional view showing an essential part of the same, and FIG. 3 is an enlarged side view of a tail piece portion showing another embodiment. FIG. 4 is an enlarged side view of a tail piece portion showing still another embodiment. 1 ... Instrument main body, 5 ... Tail piece 7A, 7B, ... String, 39A, 39B, ... Piezoelectric conversion means (piezoelectric element) 145 (141) ,.

Claims (2)

[Scope of utility model registration request] 1. A string stretched on the instrument body and having one end locked to a tailpiece, and a string provided on the instrument body for converting an electric signal into an ultrasonic signal and supplying the ultrasonic signal to the string. The piezoelectric conversion means, and a string between the piezoelectric conversion means and the tail piece,
An electronic stringed instrument comprising: a vibration isolator that attenuates the ultrasonic signal. 2. The electronic stringed instrument according to claim 1, wherein the vibration isolator is attached to a tailpiece.