Musical tone generation and indication device and manufacturing method thereof

Abstract

To stabilize sensitivity of an output signal to a pressing force in a musical tone generation and indication device.SOLUTION: An embodiment of the present invention comprises: a printed circuit board 10 having a first electrode 121 and a second electrode 122; a carbon sheet 30 containing PTFE particles of a particle diameter of 5 μm or less; an insulating spacer 20 separating the carbon sheet 30 from the printed circuit board; a rubber pad 40 pressing the carbon sheet 30; and a musical tone generation and indication unit 200 that outputs a musical tone generation and instruction in response to the pressed carbon sheet 30 coming into contact with the first electrode 121 and the second electrode 122.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present invention relates to a musical tone generating instruction device such as a pad device and a method for manufacturing the same. [Background technology]

[0002] There is known an electronic percussion instrument that has a pad and produces various percussion sounds such as drum sounds and percussion sounds when the pad is struck by hand or stick. The electronic percussion instrument detects the striking operation of the performer striking the pad surface with a hand or stick and outputs an instruction to generate a musical sound such as a percussion sound.

[0003] A sensor for detecting an impact on the pad surface is disclosed in, for example, Patent Document 1. In the sensor disclosed in Patent Document 1, a carbon sheet layer serving as an upper electrode and a carbon pattern layer serving as a lower electrode are arranged opposite each other, and the pad being impacted presses the upper electrode against the lower electrode. At that time, the pad is elastically deformed by the pressing force, so the pattern density of the carbon pattern of the lower electrode in contact with the upper electrode changes from sparse to dense depending on the pressing force. As a result, an output signal according to the pressing force is obtained from the sensor. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] JP 2019-15923 A Summary of the Invention [Problem to be solved by the invention]

[0005] According to the technology described in the above-mentioned Patent Document 1, an output signal corresponding to the pressure applied to the pad can be obtained from a sensor. However, in order to enhance the expressiveness of percussion performance, it is necessary to stabilize the sensitivity of the output signal to the pressure.

[0006] The present invention has been made in view of the above circumstances, and has an object to provide a technical means for stabilizing the sensitivity of the output signal of a sensor to a pressing force. [Means for solving the problem]

[0007] The present invention provides a musical sound generation instruction device comprising: a printed circuit board having a first electrode and a second electrode; a carbon sheet containing PTFE particles having a particle size of 5 μm or less; an insulating spacer for separating the carbon sheet from the printed circuit board; a pressing section for pressing the carbon sheet; and a musical sound generation instruction section for outputting a musical sound generation instruction in response to the pressed carbon sheet coming into contact with the first electrode and the second electrode. [Brief description of the drawings]

[0008] [Figure 1] 1 is a cross-sectional view showing a configuration of a pad device which is an embodiment of a musical sound generation instruction device according to the present invention; [Diagram 2] FIG. 2 is a plan view of the printed circuit board according to the embodiment. [Diagram 3] 3 is a circuit diagram of a musical tone generation instruction unit in the embodiment. [Figure 4] FIG. 2 is a cross-sectional view of the pad device. [Diagram 5] 4 is an enlarged cross-sectional view of the pad device in the vicinity of a contact area between a carbon sheet and a printed circuit board. FIG. [Figure 6] 11 is a diagram illustrating the dependency of the resistance value between the first electrode and the second electrode of the pad device on the pressing force. FIG. [Figure 7] 11 is a diagram illustrating the dependency of the output voltage change amount on the pressing force in the pad device. FIG. [Figure 8] 6 is a diagram showing the relationship between the amount of change in output voltage and velocity in the pad device. FIG. [Figure 9] 4 is a diagram illustrating an example of the relationship between pressing force and velocity in the pad device. FIG. [Figure 10] 4A to 4C are diagrams showing a carbon sheet manufacturing process in the embodiment. [Figure 11] FIG. 4 is a diagram showing a first electrode and a second electrode in another embodiment of the present invention. [Figure 12] FIG. 4 is a diagram showing a first electrode and a second electrode in another embodiment of the present invention. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0009] Hereinafter, an embodiment of the present invention will be described with reference to the drawings.

[0010] FIG. 1 is a cross-sectional view showing the configuration of a pad device 100 which is an embodiment of a musical tone generation instruction device according to the present invention. As shown in FIG. 1, the pad device 100 is a device formed by laminating a printed circuit board 10, an insulating spacer 20, a carbon sheet 30, and a rubber pad 40. Here, the printed circuit board 10 is a board formed by laminating a gold-plated pattern 12 on an insulating substrate 11. The carbon sheet 30 is a sheet formed by applying a carbon ink layer 32 to a PET (polyethylene terephthalate) film 31 which is a flexible film. The carbon ink layer 32 contains PTFE (polytetrafluoroethylene) particles. The carbon ink layer 32 is applied to the PET film 31 by, for example, screen printing. The carbon sheet 30 is laminated on the printed circuit board 10 with the carbon ink layer 32 facing the gold-plated pattern 12 of the printed circuit board 10. The insulating spacer 20 separates the carbon sheet 30 from the printed circuit board 10. The insulating spacer 20 may be a wall-shaped insulating spacer laminated to form the four sides of a rectangle, or may be a plurality of cylindrical or prismatic insulating spacers. The rubber pad 40 is a pressing part that presses the carbon sheet 30 when struck by the player's finger. The carbon sheet 30 is bent by the pressing part, and the carbon ink layer 32 of the carbon sheet 30 comes into contact with the gold plating pattern 12 of the printed circuit board 10.

[0011] 2, the gold-plated pattern 12 of the printed circuit board 10 includes a first electrode 121 and a second electrode 122. In the illustrated example, the first electrode 121 and the second electrode 122 are each a comb-shaped electrode, and are arranged on the printed circuit board 10 at a distance from each other.

[0012] 2 illustrates a contact area 35 between the carbon sheet 30 on the printed circuit board 10 and the rubber pad 40, which is generated by striking the rubber pad 40. In this contact area 35, the first electrode 121 is connected to the second electrode 122 via the carbon ink layer 32. Therefore, the larger the area of ​​the contact area 35, the lower the resistance between the first electrode 121 and the second electrode 122.

[0013] The pad device 100 according to this embodiment has a musical sound generation instruction section 200 shown in Fig. 3. This musical sound generation instruction section 200 includes a sensor circuit 210 and a conversion circuit 220. This sensor circuit 210 and conversion circuit 220 may be mounted on the printed circuit board 10 or may be mounted on another printed circuit board.

[0014] The sensor circuit 210 is a circuit in which a resistor 211 having a predetermined resistance value and a resistor 212 between the first electrode 121 and the second electrode 122 are connected in series between a power supply and ground. The intermediate node between the resistors 211 and 212 is the output node of the sensor circuit 210.

[0015] 4, when the rubber pad 40 is struck, the rubber pad 40 and the carbon sheet 30 are deflected by the strike, and the carbon sheet 30 comes into contact with the printed circuit board 10. The area of ​​the contact region 35 of the carbon sheet 30 on the printed circuit board 10 increases in accordance with the pressing force.

[0016] Fig. 5 is an enlarged cross-sectional view of the carbon sheet 30 and the printed circuit board 10 in the contact area 35 in Fig. 4. In this embodiment, PTFE particles 321 are filled in the carbon ink layer 32 of the carbon sheet 30. As a result, unevenness is created on the surface of the carbon ink layer 32 that contacts the surface of the printed circuit board 10. In Fig. 5, the convex areas are indicated by the reference numeral 351. When the pressing force against the carbon ink layer 32 is increased, these convex areas 351 come into contact in sequence and become conductive with the printed circuit board 10, resulting in a gradual change in the resistance value of the carbon ink layer 32.

[0017] In this embodiment, since the carbon ink layer 32 contains a large number of PTFE particles 321, the change in the resistance value of the carbon ink layer 32 with respect to the change in pressing force becomes gentler than when the carbon ink layer 32 does not contain the PTFE particles 321. Therefore, the dynamic range as a pressing force sensor is wider.

[0018] When the contact area between the carbon sheet 30 and the printed circuit board 10 increases in response to the pressing force, the resistance value of the resistor 212 between the first electrode 121 and the second electrode 122 decreases. Fig. 6 is a diagram illustrating the dependency of the resistance value of the resistor 212 on the pressing force. As illustrated in Fig. 6, the resistance value of the resistor 212 decreases in accordance with the increase in the pressing force, tracing a smooth curve that bulges downward.

[0019] In response to this decrease in resistance, the voltage of the output node decreases from a predetermined reference voltage (the voltage of the output node when no impact is applied). For convenience, the amount of decrease in the voltage of the output node from the reference voltage will be referred to as the output voltage change. Figure 7 is a diagram illustrating the dependency of the output voltage change on the pressing force.

[0020] The conversion circuit 220 is a circuit that outputs a musical tone generation command having a velocity according to the amount of change in output voltage. The conversion circuit 220 stores a table that associates the amount of change in output voltage with velocity, as shown in Fig. 8. The conversion circuit 220 converts the amount of change in output voltage obtained from the output voltage of the sensor circuit 221 into a velocity according to this table, and outputs a musical tone generation command including this velocity. Fig. 9 is a diagram illustrating the dependency of velocity on pressing force.

[0021] However, the inventors of the present application have noticed that the pad device 100 according to this embodiment has a certain problem. That is, it is a problem related to the stability of the sensitivity of the output voltage change amount to the pressing force. Specifically, this problem consists of a first and a second problem. The first problem is that the sensitivity of the output voltage change amount to the pressing force varies depending on the striking position of the rubber pad 40 (i.e., sensitivity variation occurs within the pad). The second problem is that the sensitivity of the output voltage change amount to the pressing force becomes unstable when the striking force is weak.

[0022] The inventors of the present application investigated the causes of the first and second problems. As a result, they presumed that the following points were the causes of the first and second problems: That is, there was variation in the particle size of the PTFE particles contained in the carbon ink layer 32, and it was presumed that this variation reduced the stability of the sensitivity.

[0023] Therefore, the inventors of the present application have conducted a process of trial and error to solve the above problems, and as a result, have arrived at a carbon sheet manufacturing process 500 shown in Fig. 10. This carbon sheet manufacturing process 500 is a process for manufacturing the carbon sheet 30 shown in Fig. 1, and comprises a crushing process 510, a mixing process 520, and a coating process 530.

[0024] In the pulverization step 510, the PTFE particles are compressed and sheared in a roll mill to pulverize them to a particle size of 5 μm or less. Specifically, the PTFE particles before pulverization are 18 μm in diameter, but some particles of about 1 to 20 μm are mixed in. In the pulverization step 510, these PTFE particles are pulverized. By passing through this pulverization step 510, the particle size of the PTFE particles becomes mainly about 0.1 to 5 μm. In reality, there is a small amount of particles of about 20 μm that have not been completely pulverized. However, the PTFE particles have a small particle size and little variation.

[0025] In the mixing process 520, the PTFE particles that have been through the pulverizing process 510 are mixed with carbon and ink resin in a mixer to produce carbon ink. Then, in the coating process 530, the carbon ink (containing PTFE particles) obtained in the mixing process 520 is screen-printed on a PET film 31 to form a carbon ink layer 32.

[0026] The above-mentioned problems were solved by carrying out this carbon sheet manufacturing process 500. Specifically, the sensitivity variation in the output voltage change amount relative to the pressing force within the pad was reduced. Also, the sensitivity of the output voltage change amount relative to the pressing force during weak hitting was stabilized.

[0027] Although one embodiment of the present invention has been described above, the present invention may have other embodiments. For example, in the above embodiment, the comb-shaped first electrode 121 and second electrode 122 are provided on the printed circuit board 10, but the shapes of the first electrode and second electrode are not limited to this. For example, as shown in FIG. 11, the printed circuit board 10 may be provided with the first electrode 121a and the second electrode 122a in a spiral shape spaced apart from each other. Alternatively, as shown in FIG. 12, the printed circuit board 10 may be provided with the first electrode 121b and the second electrode 122b in a concentric circle shape spaced apart from each other. [Explanation of symbols]

[0028] 100...pad device, 10...printed circuit board, 11...insulating substrate, 12...gold-plated pattern, 20...insulating spacer, 30...carbon sheet, 31...PET film, 32...carbon ink layer, 40...rubber pad, 321...PTFE particles, 35...contact area, 351...convex area, 210...sensor circuit, 211, 212...resistor, 220...conversion circuit, 200...musical tone generation indicator, 121, 121a, 121b...first electrode, 122, 122a, 122b...second electrode.

Claims

1. a printed circuit board having a first electrode and a second electrode; A carbon sheet containing PTFE particles having a particle size of 5 μm or less; an insulating spacer for separating the carbon sheet from the printed circuit board; A pressing portion that presses the carbon sheet; a musical sound generation instruction unit that outputs a musical sound generation instruction in response to the pressed carbon sheet coming into contact with the first electrode and the second electrode; A musical tone generating instruction device having the following features.

2. the first electrode and the second electrode are spaced apart from each other and arranged on the printed circuit board; a contact area between the carbon sheet and the printed circuit board increases in response to the pressure applied by the pressure unit, and a signal is generated between the first electrode and the second electrode; 2. The musical sound generation instruction device according to claim 1, wherein said musical sound generation instruction section outputs said musical sound generation instruction based on said signal.

3. 2. The musical tone generating device according to claim 1, wherein said carbon sheet and said insulating spacer are printed in a laminated state.

4. 4. The musical tone generating and instructing device according to claim 3, wherein said carbon sheet is a PET film on which carbon ink is screen-printed.

5. 4. The musical tone generating device according to claim 3, wherein said insulating spacer is screen printed on said printed circuit board.

6. a printed circuit board having a first electrode and a second electrode; A carbon sheet containing PTFE particles having a particle size of 5 μm or less; an insulating spacer for separating the carbon sheet from the printed circuit board; A pressing portion that presses the carbon sheet; a musical sound generation instruction unit that outputs a musical sound generation instruction in response to the pressed carbon sheet coming into contact with the first electrode and the second electrode; A method for manufacturing a musical tone generating device having A grinding step of grinding the PTFE particles; a mixing step of mixing the PTFE particles pulverized in the pulverization step into a carbon ink; a coating step of coating the carbon ink on a flexible film to form the carbon sheet; A method for manufacturing a musical tone generating instruction device comprising:

7. In the pulverization step, the PTFE particles are pulverized to a particle size of 5 μm or less. The method according to claim 6.

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