Patent US3673303A successfully refreshed from Google Patents.
US3673303A
Expired / Lapsed
US
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Voltage generating device for controlling musical tone output from electronic musical instruments
Assignee: Nippon Gakki Co Ltd
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Filing: 1970-09-01
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Granted: 1972-06-27
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Expires: 1990-09-01
Abstract
Abstract There is disclosed a voltage generating device of compact structure for controlling musical tone output signals from an electronic keyboard musical instrument to a level corresponding to the magnitude of a key depressing force or the velocity with which the key is depressed. Below the keyboard is positioned a non-magnetic case which supports two parallel magnetic cores and a magnet disposed therebetween which are common to a plurality of keys, and on at least one of the two magnetic cores there are fitted a plurality of coils in a manner that the coils correspond to the respective keys. There is mounted on the underside of each key a magnetic material constituting a magnetic circuit along with the two magnetic cores and the magnet received in the case. On depressing a key, the magnetic material mounted on the key is drawn near the two magnetic cores to generate in the coil a voltage having a level corresponding to the velocity with which the key is depressed, the voltage being used in controlling the corresponding musical tone output signal.
Inventors
- 👤 Hiroshi Amano
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-06 21:12
CPC Classifications
G; G10; G10H; G10H1/00; G10H1/02; G10H1/04; G10H1/053; G10H1/055; G10H1/0555; Y; Y10; Y10S; Y10S84/00; Y10S84/07
Claims Analysis
Total Claims: 13
Claim 1
Independent Claim
243 words
For use in a keyboard type electronic musical instrument, a voltage generating arrangement for producing electrical signals in response to depression of the keys comprising in combination: a plurality of keys arranged side by side, each supported so as to allow one end thereof to rock vertically in a conventional musical keyboard arrangement; an elongated non-magnetic housing positioned beneath said keys in a plane substantially parallel thereto and extending substantially transversely of the longitudinal axes of the individual keys; a pair of elongated magnetic core members supported in spaced parallel relation to each other within said housing, at least one of said core members having a plurality of spaced parallel pole piece projections equal in number to the number of keys; a plurality of coils, one wound around each of said pole piece projections; an elongated first member of magnetic material received within said housing, positioned between and in contact with the lower portion of said core members and defining therewith a substantially channel shaped magnetic circuit, the open side of said channel facing vertically upwardly toward the underside of said keys; a second member of magnetic material attached to the underside of each of the keys, one of said first and second magnetic members being a permanent magnet; whereby when anyone of said keys is depressed, a voltage is generated in the corresponding coil and the magnitude of said voltage is a function of the speed with which the key is depressed.
Claim 2
Dependent Claim
243 words
For use in a keyboard type electronic musical instrument, a voltage generating arrangement for producing electrical signals in response to depression of the keys comprising in combination: a plurality of keys arranged side by side, each supported so as to allow one end thereof to rock vertically in a conventional musical keyboard arrangement; an elongated non-magnetic housing positioned beneath said keys in a plane substantially parallel thereto and extending substantially transversely of the longitudinal axes of the individual keys; a pair of elongated magnetic core members supported in spaced parallel relation to each other within said housing, at least one of said core members having a plurality of spaced parallel pole piece projections equal in number to the number of keys; a plurality of coils, one wound around each of said pole piece projections; an elongated first member of magnetic material received within said housing, positioned between and in contact with the lower portion of said core members and defining therewith a substantially channel shaped magnetic circuit, the open side of said channel facing vertically upwardly toward the underside of said keys; a second member of magnetic material attached to the underside of each of the keys, one of said first and second magnetic members being a permanent magnet; whereby when anyone of said keys is depressed, a voltage is generated in the corresponding coil and the magnitude of said voltage is a function of the speed with which the key is depressed.
Claim 3
Dependent Claim
37 words
The voltage generating device according to claim 1 wherein said housing is supported at one end by a keyboard supporting frame and at the other end by a stopper member for regulating the range of key depression.
Claim 4
Dependent Claim
33 words
The voltage generating device according to claim 2 wherein said housing is supported by tHe keyboard supporting frame by means capable of varying the position of the case with respect to the keyboard.
Claim 5
Dependent Claim
98 words
The voltage generating device according to claim 1 wherein said housing has partition walls jointly defining a rectangular space set up on the bottom plate thereof; said first and second magnetic cores are received in said case in such a manner as to extend along the inner surfaces of the opposite longitudinal partition walls; said first member is interposed between said two magnetic cores in close contact therewith; and a corrugated plate spring inserted into the space defined between at least one of said magnetic cores and the inner surface of one of the opposite longitudinal partition walls.
Claim 6
Dependent Claim
102 words
The voltage generating device according to claim 4 wherein at least two projecting rods are erected at that part of the bottom plate of said case which is defined by its partition walls so as to be arranged in a straight line with a predetermined spacing in the direction of key arrangement; and said first member is perforated with at least two apertures similarly arranged in a straight line in the direction of key arrangement with the same spacing at which said projecting rods are disposed, said apertures allowing said projecting rods to pass therethrough thereby securely to fix said first member.
Claim 7
Dependent Claim
113 words
The voltage generating device according to claim 1 wherein the magnetic core other than the magnetic core fitted with said coils is perforated with at least one aperture, and a retaining plate having at least one first engaging strip integrally formed therewith and fitted into said aperture and at least one second engaging strip integrally formed therewith and inserted into the interspace between the adjacent projections formed on said magnetic core, whereby the fitting of said first engaging strip into said aperture and the insertion of said second engaging strip into the interspace between the adjacent projections formed on said latter magnetic core enable said first member to be securely held in place.
Claim 8
Dependent Claim
58 words
The voltage generating device according to claim 1 wherein each of said second members are bent at both ends to form two leg members extending in slightly offsetting relationship with respect to said two magnetic cores respectively, whereby, when each of said keys is depressed halfway said two leg members are drawn closest to said two magnetic cores.
Claim 9
Dependent Claim
86 words
The voltage generating device according to claim 7 wherein one of said two leg members which is positioned closer to the point at which each of said keys is supported has a greater length than the other, and one of said magnetic cores which corresponds to the longer leg member has a smaller height than the other which corresponds to the shorter leg member, so that, upon key depression, the two leg members can approach simultaneously said two magnetic cores with a substantially equal space therebetween.
Claim 10
Dependent Claim
51 words
The voltage generating device according to claim 1 wherein each of said second members has two projecting cutout strips corresponding to said first and second magnetic cores respectively, so that when each of said keys is depressed halfway, the projecting cutout strips approach closest to said first and second magnetic cores.
Claim 11
Dependent Claim
67 words
The voltage generating device according to claim 1 wherein each of said second members is perforated with two apertures facing said first and second magnetic cores, so that when each of said keys is depressed halfway, each of said second members is drawn nearest to said first and second magnetic cores, and upon further key depression, said first and second magnetic cores enter said two apertures respectively.
Claim 12
Dependent Claim
14 words
The combination defined by claim 1 in which said first members are permanent magnets.
Claim 13
Dependent Claim
14 words
The combination defined by claim 1 in which said second members are permanent magnets.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1975-06-27 | 1975-12-27 | 1976-06-27 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1979-06-27 | 1979-12-27 | 1980-06-27 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1983-06-27 | 1983-12-27 | 1984-06-27 | $7700.00 | Window Closed / Lapsed |