Apparatus and method for detecting displacement of a movable member of an electronic musical instrument

• US 20060096448A1
• Filed: 11/05/2004
• Published: 05/11/2006
• Est. Priority Date: 11/05/2004
• Status: Active Grant

• Current Assignee: Roland Corporation (Taiyo Pacific Partners LP)
• Original Assignee: Roland Corporation (Taiyo Pacific Partners LP)
• Inventors: Arai, Kazuhiro, Yoshino, Kiyoshi
• Granted Patent: US 7,459,626 B2
• Time in Patent Office: Days
• US Class Current: 84/734
• CPC Class Codes: G10H 1/34 Switch arrangements, e.g. keyboards or mechanical switches specially adapted for electrophonic musical instruments
• CPC Class Codes: G10H 2220/561 Piezoresistive transducers, i.e. exhibiting vibration, pressure, force or movement -dependent resistance, e.g. strain gauges, carbon-doped elastomers or polymers for piezoresistive drumpads, carbon microphones
• CPC Class Codes: G10H 2230/331 Spint cymbal hihat, e.g. mimicking high-hat cymbal; Details of the pedal interface, of the pedal action emulation or of the generation of the different sounds resulting from this pedal action

Abstract

An apparatus for detecting the displacement of a movable member of an electronic musical instrument. The apparatus has superior mechanical durability compared to displacement sensors of the past and can withstand long-term use. The apparatus includes a sensor that provides a detectable electrical characteristic having a value and a spring that, when compressed upon displacement of the movable member acts with the sensor, causing the value of the electrical characteristic to change. The value of the electrical characteristic represents the amount of displacement of the movable member and is used by a controller of the electronic musical instrument.

Claims

1. A displacement sensor comprising:

a sensor sheet having a surface area and providing electrical resistance having a value, the value of the electrical resistance changing with the surface area of the sensor sheet that is pressed; and

a coil spring having a conical shape with a wider end, the wider end of the coil spring disposed opposite to the sensor sheet such that the coil spring presses an increasing surface area of the sensor sheet as the coil spring is compressed.

2. The displacement sensor as recited in claim 1, the sensor sheet of the displacement sensor further comprising:

a sheet material providing electrical conductivity; and

an electrode pattern that is disposed opposite the sheet material and is formed in a radial shape from a center of the pattern toward a peripheral edge of the pattern.

3. A displacement sensor for detecting displacement of a movable object, comprising:

a member providing a detectable electrical characteristic that has a value; and

a spring that, upon displacement of the movable object, is compressed and acts with the member providing the detectable electrical characteristic;

wherein action between the spring and the member providing the detectable electrical characteristic causes the value of the electrical characteristic to change.

4. The displacement sensor as recited in claim 3, wherein the member providing the detectable electrical characteristic has the shape of a sheet.

5. The displacement sensor as recited in claim 3, wherein the value of the electrical characteristic represents an amount of displacement of the movable object and is input to a controller of a musical instrument that produces a sound signal dependent, at least in part, on the value of the electrical characteristic.

6. The displacement sensor as recited in claim 3, wherein the spring is a coil spring.

7. The displacement sensor as recited in claim 3, wherein the spring is a coil spring that has a conical shape.

8. The displacement sensor as recited in claim 3, wherein the spring and the member providing the detectable electrical characteristic are contained within a frame.

9. The displacement sensor as recited in claim 3, wherein

the spring and the member providing the detectable electrical characteristic are contained within a cylindrical frame that has a concave end surface;

and

the frame is notched to receive a protuberant section of the member providing the detectable electrical characteristic.

10. The displacement sensor as recited in claim 3, wherein an elastic member is disposed between the spring and the member providing the detectable electrical characteristic.

11. The displacement sensor as recited in claim 3, wherein a member that distributes force of the action between the spring and the member providing the detectable electrical characteristic is disposed between the spring and the member providing the detectable electrical characteristic.

12. The displacement sensor as recited in claim 3, wherein the member providing the detectable electrical characteristic comprises:

a first member having at least one surface that is electrically conductive;

a second member having a center region, a peripheral region, and at least two electronically independent nodes; and

a third member disposed between the first member and the second member that limits electrical conductance via the at least one surface of the first member between the at least two electronically independent nodes of the second member when the spring is in a first state of compression and that facilitates electrical conductance via the at least one surface of the first member between the at least two electronically independent nodes of the second member when the spring is in a second state of compression;

wherein the spring is compressed to a greater degree when the spring is in the second state of compression relative to when the spring is in the first state of compression.

13. The displacement sensor as recited in claim 12, wherein in the first state of compression the spring is uncompressed.

14. The displacement sensor as recited in claim 12, wherein:

the electrical characteristic is an electrical resistance; and

the electrical resistance changes with displacement of the movable object, which changes a degree to which the spring is compressed.

15. The displacement sensor as recited in claim 14, wherein the degree to which the spring is compressed changes a degree to which the at least one surface of the first member provides electrical conductance between the at least two electronically independent nodes of the second member.

16. The displacement sensor as recited in claim 12, wherein one of the at least two electronically independent nodes of the second member comprises a connected series of radial segments disposed between the center region of the second member and the peripheral region of the second member.

17. The displacement sensor as recited in claim 3, wherein:

the spring has an axis, through which the spring is compressed upon the displacement of the movable object; and

the member providing the detectable electrical characteristic has a hole that is concentric with the axis of the spring.

18. The displacement sensor as recited in claim 17, wherein the hole in the member providing the detectable electrical characteristic receives a shaft disposed through the axis of the spring.

19. The displacement sensor as recited in claim 3, wherein:

the spring is a coil spring composed of a spring material having a length arranged in multiple loops; and

upon compression of the spring, one or more of the multiple loops engage the member providing the detectable electrical characteristic such that the length of the spring material engaging the member providing the detectable electrical characteristic changes with an amount of compression of the spring.

20. A system for generating an electrical characteristic, the electrical characteristic having a value, based on operation by a user, comprising:

a pedal that is displaced by the user;

a plate on which a first edge of the pedal is mounted; and

a displacement sensor mounted between the plate and a second edge of the pedal;

wherein the displacement sensor comprises;

a member providing the electrical characteristic; and

a spring that, upon displacement of the pedal, acts with the member providing the electrical characteristic, causing the value of the electrical characteristic to change.

21. The system as recited in claim 20, wherein the system further comprises a shaft that, upon displacement of the pedal, pushes the spring, causing the spring to compress and act with the member providing the electrical characteristic.

22. The system as recited in claim 20, wherein the system further comprises a shaft attached to a plate that, upon displacement of the pedal, pushes the spring, causing the spring to compress and act with the member providing the electrical characteristic.

23. An electronic musical instrument comprising the system as recited in claim 20, wherein the value of the electrical characteristic represents an amount of displacement of the pedal and is input to a controller of the electronic musical instrument that produces a sound signal dependent, at least in part, on the value of the electrical characteristic.

24. The system as recited in claim 20, wherein the value of the electrical characteristic with respect to displacement of the pedal may be adjusted by moving the displacement sensor and the second edge of the pedal relative to each other.

25. The system as recited in claim 20, wherein the spring is a coil spring.

26. The system as recited in claim 20, wherein the spring is a coil spring in a conical shape.

27. The system as recited in claim 20, wherein the member providing the electrical characteristic comprises:

a first member having at least one surface that is electrically conductive;

a second member having a center region, a peripheral region, and at least two electronically independent nodes; and

a third member disposed between the first member and the second member that limits electrical conductance via the at least one surface of the first member between the at least two electronically independent nodes of the second member when the spring is in a first state of compression and that facilitates electrical conductance via the at least one surface of the first member between the at least two electronically independent nodes of the second member when the spring is in a second state of compression;

wherein the spring is compressed to a greater degree when the spring is in the second state of compression relative to when the spring is in the first state of compression.

28. The system as recited in claim 27, wherein in the first state of compression the spring is uncompressed.

29. The system as recited in claim 20, wherein:

the electrical characteristic is an electrical resistance; and

the electrical resistance changes with displacement of the pedal, which changes a degree to which the spring is compressed.

30. The system as recited in claim 29, wherein the degree to which the spring is compressed changes a degree to which the at least one electrically conductive surface of the first member provides electrical conductance between the at least two electronically independent nodes of the second member.

31. The system as recited in claim 20, wherein:

the spring is a coil spring composed of a spring material having a length arranged in multiple loops; and

upon compression of the spring, one or more of the multiple loops engage the member providing the electrical characteristic such that the length of the spring material engaging the member providing the electrical characteristic changes with an amount of compression of the spring.

32. An electronic high hat cymbal system for generating an electrical characteristic having a value based on displacement of at least one cymbal member having a movable position, comprising:

a shaft having an axis;

first and second cymbal members, at least one movable relative to the other along the axis of the shaft;

a displacement sensor mounted between the first and second cymbal members, wherein;

the shaft passes through the first cymbal member, the displacement sensor and the second cymbal member; and

the displacement sensor comprises;

a member providing the electrical characteristic; and

a spring that, upon displacement of the at least one cymbal member having the movable position, acts with the member providing the electrical characteristic, causing the value of the electrical characteristic to change.

33. The electronic high hat cymbal system as recited in claim 32, further comprising a fixing component, wherein:

the shaft passes through the fixing component; and

the fixing component, upon displacement of the at least one cymbal member having the movable position, pushes the member providing the electrical characteristic, causing the spring to compress and act with the member providing the electrical characteristic.

34. The electronic high hat cymbal system as recited in claim 32, wherein the value of the electrical characteristic represents the amount of displacement of the at least one cymbal member having a movable position and is input to a controller for the electronic high hat cymbal system that produces a sound signal dependent, at least in part, on the value of the electrical characteristic.

35. The electronic high hat cymbal system as recited in claim 32, wherein the value of the generated electrical characteristic with respect to the displacement of the at least one cymbal member having the movable position may be adjusted by moving the first and second cymbal members relative to the other.

36. The electronic high hat cymbal system as recited in claim 32, wherein the spring is a coil spring.

37. The electronic high hat system as recited in claim 32, wherein the spring is a coil spring in a conical shape.

38. The electronic high hat system as recited in claim 32, wherein the member providing the electrical characteristic comprises:

a first member having at least one surface that is electrically conductive;

a second member having a center region, a peripheral region, and at least two electronically independent nodes; and

a third member disposed between the first member and the second member that limits electrical conductance via the at least one surface of the first member between the at least two electronically independent nodes of the second member when the spring is in a first state of compression and that facilitates electrical conductance via the at least one surface of the first member between the at least two electronically independent nodes of the second member when the spring is in a second state of compression;

wherein the spring is compressed to a greater degree when the spring is in the second state of compression relative to when the spring is in the first state of compression.

39. The electronic high hat system as recited in claim 38, wherein in the first state of compression the spring is uncompressed.

40. The electronic high hat system as recited in claim 32, wherein:

the electrical characteristic is an electrical resistance; and

the electrical resistance changes with displacement of the at least one cymbal member having the movable position, which changes a degree to which the spring is compressed.

41. The electronic high hat system as recited in claim 40, wherein the degree to which the spring is compressed changes a degree to which the at least one electrically conductive surface of the first member provides electrical conductance between the at least two electronically independent nodes of the second member.

42. The electronic high hat system as recited in claim 32, wherein:

the spring is a coil spring composed of a spring material having a length arranged in multiple loops; and

upon compression of the spring, one or more of the multiple loops engage the member providing the electrical characteristic such that the length of the spring material engaging the member providing the electrical characteristic changes with an amount of compression of the spring.

43. A method for detecting displacement of a movable object, comprising:

providing a member having a detectable electrical characteristic that has a value;

disposing a spring opposite to the member having a detectable electrical characteristic; and

disposing the movable object relative to the spring to compress the spring and cause the spring to act with the member having the detectable electrical characteristic upon displacement of the movable object,

wherein action between the spring and the member having the detectable electrical characteristic causes the value of the electrical characteristic to change.

44. The method as recited in claim 43, wherein the spring is a coil spring.

45. The method as recited in claim 43, wherein the spring is a coil spring in a conical shape.

46. The method as recited in claim 43, wherein providing the member having the detectable electrical characteristic comprises:

providing a first member having at least one surface that is electrically conductive;

providing a second member having a center region, a peripheral region, and at least two electronically independent nodes; and

disposing a third member between the first member and the second member that limits electrical conductance via the at least one surface of the first member between the at least two electronically independent nodes of the second member when the spring is in a first state of compression and that facilitates electrical conductance via the at least one surface of the first member between the at least two electronically independent nodes of the second member when the spring is in a second state of compression;

wherein the spring is compressed to a greater degree when the spring is in the second state of compression relative to when the spring is in the first state of compression.

47. The method as recited in claim 46, wherein in the first state of compression the spring is uncompressed.

48. The method as recited in claim 43, wherein:

the electrical characteristic is an electrical resistance; and

the electrical resistance changes with displacement of the movable object, which changes a degree to which the spring is compressed.

49. The method as recited in claim 48, wherein the degree to which the spring is compressed changes a degree to which the at least one electrically conductive surface of the first member provides electrical conductance between the at least two electronically independent nodes of the second member.

50. The method as recited in claim 43, wherein:

the spring is a coil spring composed of a spring material having a length arranged in multiple loops; and

upon compression of the spring, one or more of the multiple loops engage the member having the detectable electrical characteristic such that the length of the spring material engaging the member providing the detectable electrical characteristic changes with an amount of compression of the spring.