|Publication number||US3263551 A|
|Publication date||Aug 2, 1966|
|Filing date||May 7, 1965|
|Priority date||May 7, 1965|
|Publication number||US 3263551 A, US 3263551A, US-A-3263551, US3263551 A, US3263551A|
|Inventors||Musser Clair O|
|Original Assignee||Musser Clair O|
|Export Citation||BiBTeX, EndNote, RefMan|
|Patent Citations (5), Referenced by (4), Classifications (9)|
|External Links: USPTO, USPTO Assignment, Espacenet|
Aug. 2, 1966 c. o. MUSSER ELECTRONIC METRONOME Filed May 7. 1965 FIG. 3.
C LA IR OMAE Muas z Eon A20 D. OER/AN A Tram/z Y United States Patent 3,263,551 ELECTRONIC METRONOME (Ilair 0. Mussel", 12997 Blairwood Drive, Studio City, Calif.
Filed May 7, 1965, Ser. No. 454,026 4 Claims. (Cl. 84-484) This invention is directed to an electric metronome, and particularly to a metronome which is capable of producing a clear tone of a predetermined note and repeating the tone at a predetermined time rate.
Metronomes are well known in the musical art. Metronomes are arranged to provide a series of audible signals at a predetermined time rate so as to aid a musician in keeping his musical rendition operating at a constant rate. Metronomes are conventionally of an adjustable time rate, so that the musician may make the necessary adjustments to suit the character of the piece he is rendering. The normal tone created by a metronome is a woody click which has no particular basic frequency and thus does not interfere with the musical tones rendered. Such metronomes may be either mechanical or electronic, and a well known electronic metronome is shown in Andersen Patent No. 2,522,492.
On certain occasions it becomes desirable to create a relatively pure tone. This tone is used for tuning and can be used for checking the accuracy of tone produced 'on those instruments which do not have every note preestablished.
Accordingly, it is an object of this invention to provide a metronome which has a structure which produces a relatively pure tone.
It is another object of this invention to provide an electronic metronome which is capable of periodically producing relatively pure tones at a predetermined time rate.
It is a further object of this invention to provide means to excite a tone bar independent of the striking thereof so that a more pure note is produced by the tone bar.
Another object of this invention is to excite a tone bar by electromagnetic inductionso as to avoid the physical striking of the tone bar to create a note therefrom, and to thereby create a more pure tone, and produce a tone which does not change over a period of time due to tone bar distortion due to' striking.
It is a further object of this invention to provide a resonance chamber in conjunction with a tone bar of relatively small dimensions so that the tone bar can be placed in a relatively limited space and so that the resonance chamber which is particularly designed for the primary frequency of the tone bar amplifies such a frequency so as to make the sound clearly audible.
Other objects and advantages of this invention will become apparent from a study of the following portion of the specification, the claims and the attached drawings in which:
FIG. 1 is an isometric view of a metronome embodying the structure of this invention;
FIG. 2 is a slightly enlarged vertical section therethrough taken generally along the line 22 of FIG. 1;
FIG. 3 is a partial, enlarged vertical section taken generally along the line 3-3 of FIG. 1; and
FIG. 4 is a schematic electrical circuit of a portion of the metronome of this invention.
As an aid to understanding this invention itcan be stated in essentially summary form that it is directed to a metronome. In addition to the means for creating normal conventional time spaced clicking sounds, the metronome is also provided with means for producing time spaced musical tones.
The metronome is provided with an electronic timing device which is suitably adjustable so as to create ad- "ice instability of the output signal therefrom. The output signal is normally fixed at a predetermined time rate, which is predetermined by the adjustment. The output signal normally drives a conventional clicker mechanism which produces the conventional audible signal for the metronome. The metronome of this invention is provided with a suitable selector switch so that the timed output electronic signal can alternatively be directed to a tone bar exciting solenoid. Mounted within the. metronome is a conventional tone bar made of ferromagnetic material. The tone bar is mounted on its quarter points and is provided with a suitable resonance chamber. In view of the relatively confined space in which the tone bar is to be located its size must be such that little amplitude is created at the desired fundamental frequency thereof. Therefore, a resonance chamber, particularly designed for this fundamental frequency, is mounted in association with the tone bar so as to amplify the tone resulting from tone bar actuation and make it clearly audible. Mounted directly adjacent to and associated therewith is a solenoid coil which electromagnetically energizes the tone bar without physical contact therewith. The previously described switch connects this solenoid to the predetermined constant rate electronic signal. Thus, the tone bar is periodically excited to produce its tone.
This invention will be understood in greater detail by reference to the following portion of this specification where the drawings are described. Referring now to FIG. 1, the metronome of this invention is generally indicated at 10. The metronome 10 has a housing 12 to enclose the interior mechanism thereof and provide a framework structure therefor. The housing 12 has a bottom 14, top 16, left and right walls 18 and 20 as well as front 22 and a suitable rear closure.
Carried upon front 22 is adjustment knob 24 which is movable with respect to indicia 26. Internal connections of the adjustment knob provide suitable signal to the electronics housed in chassis 28 so that the chassis produces an output signal of the frequency adjusted by knob 24 and indicated by indicia 26.
The electronic structure for producing the output signal of a frequency in accordance with the adjustment, and the transducer which converts the electronic signal to an audible signal is well known in the art. Such is apparent in Andersen Patent No. 2,522,492, granted September 19, 1950, the entire disclosure of which is incorporated herein by this reference.
As is best seen in FIG. 3, the conventional transducer structure for converting the electronic signal to the audible signal comprises solenoid coil 30 which is mounted by bracket 32 upon the top chassis 2-8. Core 34 is fixedly mounted within the coil 30, and is arranged so that upon energization of coil 30 ferromagnetic disc 36 is attracted by electromagnetic attraction. Ferromagnetic disc 36 is mounted upon a thin wood diaphragm 38. Attraction causes mechanical contact with core 34 or with ferromagnetic flux guide 39. Holes 40 in right wall 20 permit the clicking sound of the disc 36 striking core 34 to be audible from the outside of metronome 10. If desired, bracket 32 can be made adjustable with respect to chassis 28 so as to change the amount of deflection required of dia phragm 38 for contact of disc 36 with core 34 and/or tude, but at the same time it definitely does not have any particular tonal value wherein a particular frequency and its overtones are dominant. Therefore, the tone of the clicker can be described as atonal.
Also mounted within housing 12 is solenoid coil 42. Coil 42 is mounted upon bracket 44 which is secured to the bottom of resonance chamber 46. The resonance chamber in turn is secured within housing 12.
Ferromagnetic tone bar 48 is mounted upon posts 50 and 52 which are substantially at the nodes of tone bar 48. By this mounting, tone bar 48 is located in conjunction with the resonance chamber 46 which has a resonance opening 54 substantially adjacent the center of tone bar 48. Resonance chamber 46 is tuned to the tone of the tone bar to enhance its audio output. Furthermore, iron core 56 is located by this mounting structure to be very closely adjacent to the tone bar 48 without contacting it. However, core 56 is sufficiently close to the tone bar to permit the electromagnetic flux generated by coil 42 and directed by the iron of core 56 to act upon tone bar 48. The electromagnetic attraction is suflicient to bend the tone bar 48 to create a tone therefrom.
Tone bar 48 is preferably of such dimensions as to have a fundamental frequency in accordance with the international standard of 440 cycles per second, which is the standard for the note A. In view of the limited space in which the tone bar 48 is situated, it must be of relatively short nature and thus must be relatively thin in order to havea fundamental frequency of 440 cycles. Since it is thin, the amplitude of the resulting compressive sound waves created in the adjacent air is such that the tone is barely audible, or perhaps inaudible to the average human ear. In order to enhance the amplitude so as to make it clearly audible, resonance chamber 46 with opening '54 is employed. The opening 54 is adjacent the maximum deflection point of tone bar 48 at its fundamental frequency so as to permit maximum actuation of the air column within the resonance chamber. The resonance chamber is especially designed so as to have adequate volume of air to be able to resonate at the fundamental frequency, and still be of relatively limited size. Thus, the resonance chamber is able to amplify the signal created by tone bar 48 and produce a properly audible signal. In order to enhance this signal openings 57 may be formed in the side 18.
Referring now to FIG. 4, chassis 28 is connected to a suitable supply of electric power. This may be an internal battery or it may be an external source of electric power. The output signal from the chassis 28 is transmitted by line 58 to single pole double throw switch 64. Contact 60 is connected through signal line 66 to coil 30 and thence by line 68 back to chassis 28. Further-more, contact 62 is connected by signal line 70 to coil 42. Coil 42 is connected to line 68. Lamp 72 is mounted on the top of housing 12 so as to be clearly visible from all sides. Lamp 72 is connected between lines 58 and 68 so as to be operative when either the coil 30 or coil 42 is energized. It is clear that lamp 72 is optional, and supplies a visual signal in conjunction with the clicker or tone signal.
It can thus be seen that when in operation, the periodic signal generated in line 58 passes through normally closed contact 60, when switch 64 is connected thereto, and thence through line 66, coil 30 and line 68 to cause pe riodic actuation of core 34. Thus, the periodic electric signal in line 58 causes periodic motion of core 34 against disc 36 to make the conventional clicking sound. However, upon turning of switch 64, contact 60 is opened and the contact 62 is closed. Thus, the periodic signal in output line 58 passes through contact 62, line 70, coil 42 and line 68, back to the chassis 28. When this occurs, the periodic electrical signal causes deflection of tone bar 48 and this deflection in turn produces a periodically repeated tone.
It is more important to note that electromagnetic actuation of tone bar 48 causes a more clear tone than the mechanical striking thereof so that a more clear tone is produced. The mechanical striking of a tone bar or tuning fork soon mechanically distorts it to a suflicient extent that it no longer produces a true tone. However, with the electromagnetic actuation of tone bar 48, such is clearly not the case and a clear, accurate tone is produced for the full life of the metronome 10. This tone is useful in tuning instruments and is useful in producing the periodic tone signal necessary for good musical rendition.
This invention having been described in its preferred embodiment, it is clear that it is susceptible to numerous modifications and changes within the ability of those skilled in the art without the exercise of the inventive faculty. Accordingly, the scope of this invention is defined by the scope of the following claims.
1. An electronic metronome, said electronic metronome comprising:
a housing, an electronic signal generator positioned within said housing, and an audible sound producing device positioned within said housing;
said audible sound producing device comprising a solenoid having a core therein, tone generating means mounted within said housing, said tone generating means being capable of being magnetically excited to produce a substantially clear tone, said core being positioned adjacent'to said tone generating means and out of contact therewith so that electrical energization of said solenoid produces electro-magnetic force which causes deflection of said tone generating means to cause it to emit a tone, said solenoid being connected to said electronic signal generator, said tone generating means being arranged to emit a substantially clear tone;
a resonance chamber mounted within said housing and adjacent said tone generating means so as to resonate the tone of said tone generating means, said resonance chamber having an opening therein, said opening in said resonance chamber being adjacent a portion of said tone generating means which moves upon emission of an audible signal from said tone generating means, said resonance chamber being coupled with said tone generating means by means of an air column extending from said tone generating means through said opening in said resonance chamber and into said resonance chamber so that said tone generating means is non-mechanically audibly coupled to said resonance chamber and said resonance chamber amplifies the tonal sound of said tone generating means.
2. An electronic metronome, said electronic metronome comprising:
a housing, an electronic signal generator, and first and second audible sound producing devices;
said housing comprising at least a front wall and side wall;
said electronic signal producing device comprising an electronic chassis, adjustment means mounted upon said front wall of said housing, said adjustment means being electrically connected to said chassis, an electric output line connected to said chassis, said chassis being electronically arranged to regularly periodically emit an electric signal into said output line, said adjustment means connected to said chassis being arranged to adjust the period of said electricalsignal into said output line;
a manually operable selective switch connected to said output line, said switch having first and second signal lines connected thereto and being arranged to selectively connect said first and second signal lines to said output line, so that said first and second signal lines are selectively energized by said output line;
said first audible sound producing device comprising a first solenoid having a core therein, said core being arranged to deflect a diaphragm upon energization of said first solenoid, said deflection being arranged to produce an atonal audible signal, said first solenoid being connected to said first signal line;
said second audible sound producing device comprising a second solenoid having a fixed core therein, and a tone bar mounted within said housing, said fixed 5 core being positioned adjacent said tone bar and out of contact therewith so that electrical energization of said second solenoid produces electromagnetic deflection of said tone bar to cause it to emit a tone, said second solenoid being connected to said second signal line, said tone bar being arranged to emit a substantially clear tone;
a resonance chamber mounted within said housing and adjacent said tone bar so as to resonate the tones of said tone bar, said tone bar being coupled to said resonance chamber by an air column so that when said tone bar is actuated, compressed waves enter said resonance chamber and said resonance chamber amplifies said compressed waves so as to produce a tonal amplified audible sound so that when said manual switch is connected to energize said first signal line, an atonal periodic signal is produced and when said electric switch is connected to energize said second signal line, a tonal signal is produced.
3. The electronic metronome of claim 2 wherein said tone bar is mounted at its quarter points and said resonance chamber has an opening therein adjacent to the center of said tone bar.
4. An electronic metronome, said electronic metronome comprising:
a housing, an electronic signal generator positioned within said housing, and an audible sound producing device positioned within said housing;
said audible sound producing device comprising a solenoid having a fixed core therein, a tone bar mounted 35 within said housing, said fixed core being positioned adjacent to said tone bar and out of contact there with so that electrical energization of said solenoid produces electromagnetic force which causes deflection of said tone bar to cause it to emit a tone, said solenoid being connected to said electronic signal generator, said tone bar being arranged to emit a substantially clear tone;
a resonance chamber mounted within said housing and adjacent said tone bar so as to resonate the tones in said tone bar, said resonance chamber having an opening therein, said opening in said resonance chamber being adjacent a portion of said tone bar which moves upon emission of an audible signal from said tone bar, said resonance chamber being coupled with said tone bar by means of an air column extending from said tone bar, through said opening in said resonance chamber and into said resonance chamber so that said tone bar is non-mechanically audibly coupled to said resonance chamber and said resonance chamber amplifies the total sound of said tone bar.
References Cited by the Examiner UNITED STATES PATENTS 1,930,997 10/1933 Fascinato 58-130 2,152,177 3/1939 Eisenbeis et a1. 84-454 2,307,104 1/1943 Bossard 84-410 X 2,522,492 9/ 1950 Andersen 58130 X 3,038,120 6/1962 Bernstein et a1. 58130 X LOUIS J. CAPOZI, Primary Examiner.
STEPHEN I. TOMSKY, LEO SMILOW, Examiners.
|Cited Patent||Filing date||Publication date||Applicant||Title|
|US1930997 *||Nov 29, 1932||Oct 17, 1933||Fascinato Lorenzo G||Musical time indicator|
|US2152177 *||Apr 27, 1937||Mar 28, 1939||Eisenbeis William J||Sound-wave generator|
|US2307104 *||Mar 5, 1942||Jan 5, 1943||Mary W Agnew||Signaling device|
|US2522492 *||May 29, 1946||Sep 19, 1950||Crystal Res Lab Inc||Electronic metronome|
|US3038120 *||Aug 19, 1959||Jun 5, 1962||Bernstein Malcolm E||Electronic transistorized metronome|
|Citing Patent||Filing date||Publication date||Applicant||Title|
|US7582822 *||May 23, 2007||Sep 1, 2009||Stephen Olander-Waters||Metronome and system for maintaining a common tempo among a plurality of musicians|
|US9165541||Jul 6, 2012||Oct 20, 2015||Mark Pires||Percussion instrument|
|USD735265 *||Sep 14, 2012||Jul 28, 2015||Mark Pires||Percussion instrument|
|USD737365 *||Jan 30, 2013||Aug 25, 2015||Pitch Slap Percussion Llc||Percussion instrument|
|U.S. Classification||84/484, 968/820, D17/24, 84/410, 340/392.5|
|International Classification||G04F5/02, G04F5/00|