Key operating device for an electronic musical instrument

Claim 2

A keyboard device for an electronic musical instrument comprising: a plurality of keys each swingably supported and arranged in juxtaposed relationship, each of said keys having a projecting leg member to limit its swingable movement; an equal plurality of first and second means magnetically cooperating with each other to produce an electro-motive force proportional to the relative speed between them, one of said first means being attached to said projecting member of each key respectively, one of said second means being positioned respectively such that when said key is in an undepressed position, said first and second means are spaced from each other, and as said key is depressed, said first and second means approach each other and upon full depression of said key reach positions where they are closely adjacent to each other.

Claim 3

The device as claimed in claim 1 wherein said first means is a magnet, and said second is a coil.

Claim 4

The device as claimed in claim 1 wherein said first means is a coil, and said second means is a magnet.

Claim 5

The device as claimed in claim 2 further comprising a core around which said coil is wound.

Claim 6

The device as claimed in claim 2 further comprising a core around which said coil is wound.

Claim 7

The device as claimed in claim 2 further comprising a reed switch positioned adjacent to said projecting leg member, said reed switch being magnetically operated by said magnet and serving when closed to connect said coil to a dummy load.

Claim 8

The device as claimed in claim 4 wherein said magnet and core have respective end faces confronting each other, said end face of said magnet being different in size from said end face of said core.

Claim 9

The device as claimed in claim 5 wherein said magnet and core have respective end faces confronting each other, said end face of said magnet being different in size from said end face of said core.

Claim 10

The device as claimed in claim 1 wherein said second means is swingable by the depression of said key so that said second means approaches said first means.

Claim 11

The device as claimed in claim 1 further comprising lever means pivotally supported at an intermediate point thereof under said key, said lever means carrying at one end said second means and being depressed by said key at the other end thereof.

Claim 12

The device as claimed in claim 2 further comprising an adjustable screw means of magnetic material positioned under said key to exert a magnetically attracting force on said magnet which force increases the further said key is depressed.

Claim 13

A keyboard device for an electronic musical instrument comprising: a plurality of keys swingably supported and arranged in juxtaposed relationship, each of said keys having a projecting leg member to limit its swingable movement; a plurality of first and second means equal in number to the number of keys magnetically cooperating with each other and producing an electromotive force in proportion to the speed at which they move relative to each other, one of said first means being attached to said projecting leg member of each key respectively, one of said second means being positioned with respect to said first means respectively such that when said key is in an undepressed position, said first and second means are positioned most closely to each other, and when said key is depressed, said first and second means move away from each other.

Claim 14

A keyboard device for an electronic musical instrument comprising: a plurality of keys swingably supported and arranged in juxtaposed relationship, each of said keys having a projecting leg member to limit its swingable movement; a plurality of first and second means equal in number to the number of keys magnetically cooperating with each other and producing an electromotive force in proportion to the speed at which they move relative to each other, one of said first means being attached to said projecting leg member of each key respectively, one of said second means being positioned with respect to said first means respectively such that when said key is in an undepressed position, said first and second means are positioned most closely to each other, and when said key is depressed, said first and second means move away from each other.

Claim 15

The device as claimed in claim 12, wherein said first means is a magnet, and said second means is a coil.

Claim 16

The device as claimed in claim 12 wherein said first means is a coil, and said second means is a magnet.

Claim 17

The device as claimed in claim 13 further comprising a core around which said coil is wound.

Claim 18

The device as claimed in claim 14 further comprising a core around which said coil is wound.

Claim 19

The device as claimed in claim 13 further comprising a reed switch positioned adjacent to said projecting leg member, said reed switch being magnetically operated by said magnet and serving when closed to connect said coil to a dummy load.

Claim 20

The device as claimed in claim 15 wherein said magnet and core have respective end faces confronting each other, said end face of said magnet being different in size from said end face of said core.

Claim 21

The device as claimed in claim 16 wherein said magnet and core have respective end faces confronting each other, said end face of said magnet being different in size from said end face of said core.

Claim 22

A keyboard device for an electronic musical instrument comprising: a plurality of keys swingably supported and arranged in juxtaposed relationship; an equal number of magnets, one attached to each of said keys respectively; and an equal plurality of pairs of coils, one pair being positioned under each said key respectively and spaced apart from each other, said magnets being positioned most closely to one coil of each pair of said coils when said key is in an undepressed position and approaching the other of said coils as said key is depressed.

Claim 23

A keyboard device for an electronic musical instrument comprising: a plurality of keys swingably supported and arranged in juxtaposed relationship; an equal number of magnets, one attached to each of said keys respectively; and an equal plurality of pairs of coils, one pair being positioned under each said key respectively and spaced apart from each other, said magnets being positioned most closely to one coil of each pair of said coils when said key is in an undepressed position and approaching the other of said coils as said key is depressed.

Claim 24

A keyboard device for an electronic musical instrument comprising: a keyboard frame; a plurality of keys swingably supported on said frame and arranged in juxtaposed relationship; an equal plurality of magnets, one magnet being attached to each of said keys respectively; an equal plurality of threaded cores screwed into said frame; an equal plurality of coils, one coil wound around each said core respectively, said cores being positioned under said keys with a predetermined space between said magnets and cores, said space being adjustable by rotation of said threaded cores.

Claim 25

A keyboard device for an electronic musical instrument comprising: a keyboard frame; a plurality of keys swingably supported on said frame and arranged in juxtaposed relationship; an equal plurality of magnets, one magnet being attached to each of said keys respectively; an equal plurality of threaded cores screwed into said frame; an equal plurality of coils, one coil wound around each said core respectively, said cores being positioned under said keys with a predetermined space between said magnets and cores, said space being adjustable by rotation of said threaded cores.

Claim 26

The device as claimed in claim 21 further comprising a plurality of adjustable screw means of magnetic material, one screwed into said frame under each of said keys respectively and exerting a magnetically attracting force on said magnet which increases the further said key is depressed.

Claim 27

A keyboard device for an electronic musical instrument comprising: a keyboard frame; a plurality of keys swingably supported on said frame and arranged in side by side relationship; an equal plurality of spring means, one attached to each of said keys respectively and having a free end; an equal number of magnets, one carried by each said spring means respectively at the free end thereof; a equal plurality of coils mounted on said frame, and one being at a distance from each of said magnets respectively, said magnets approaching said coils when said keys are depressed.

Claim 28

A keyboard device for an electronic musical instrument comprising: a keyboard frame; a plurality of keys swingably supported on said frame and arranged in side by side relationship; an equal plurality of spring means, one attached to each of said keys respectively and having a free end; an equal number of magnets, one carried by each said spring means respectively at the free end thereof; a equal plurality of coils mounted on said frame, and one being at a distance from each of said magnets respectively, said magnets approaching said coils when said keys are depressed.

Claim 29

The device as claimed in claim 23 further comprising an equal plurality of hollow cylindrical members, one positioned under each said key respectively, said cylindrical members guiding said magnets when said keys are depressed, said coils being wound around said cylindrical members.