US1735860A - Flexed sounding board - Google Patents

Flexed sounding board Download PDF

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Publication number
US1735860A
US1735860A US180181A US18018127A US1735860A US 1735860 A US1735860 A US 1735860A US 180181 A US180181 A US 180181A US 18018127 A US18018127 A US 18018127A US 1735860 A US1735860 A US 1735860A
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sounding
flexed
elements
sound
longitudinally
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Expired - Lifetime
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US180181A
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Hutchison Miller Reese
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ACOUSTIC PRODUCTS Co
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ACOUSTIC PRODUCTS Co
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    • HELECTRICITY
    • H04ELECTRIC COMMUNICATION TECHNIQUE
    • H04RLOUDSPEAKERS, MICROPHONES, GRAMOPHONE PICK-UPS OR LIKE ACOUSTIC ELECTROMECHANICAL TRANSDUCERS; DEAF-AID SETS; PUBLIC ADDRESS SYSTEMS
    • H04R1/00Details of transducers, loudspeakers or microphones
    • H04R1/20Arrangements for obtaining desired frequency or directional characteristics
    • H04R1/22Arrangements for obtaining desired frequency or directional characteristics for obtaining desired frequency characteristic only 
    • H04R1/24Structural combinations of separate transducers or of two parts of the same transducer and responsive respectively to two or more frequency ranges

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  • This invention relates to the faithful reproduction of sound.
  • the invent' on has for its particular object the provision 'of-improved means for producing simultaneously musical notes having a wide range of frequencies, together with all the upper harmonics necessary for imparting quality or timber to music whereby the sounds of difierent musical character may be readily 1o identified.
  • The. 'nvention has particular reference to a the reproduction of orchestral, band or chord music so that the sounds produced by the difierent instruments or voices of an ensemble are emitted in the same relative intensities as in the case of the original rendition of the music.
  • this difiiculty is at least in part the result of impressing upon the ap ar-atus energy corresponding to the higher requencies of the musical register, and that when the apparatus is responding to such higher frequencies it does not faithfully respond to the energy of low frequency.
  • This difliculty is not apparent when the apparatus is reproducin the bass notes singly as in the case of a ass solo, but develops immediately when the bass notes are to be produced at the same time as the notes of higher range.- Consequently it has been found with structures of the prior art that when proper response is obtained in the case of a bass sold, the response with an ensemble of instruments is not faithful and the bass notes are not properly balanced with the higher notes, so that the music is not always reproduced with fidelity.. g
  • the energy impressing means comprises generally an electromagnetic unit having an actuating element operatively connected to the respective sounding element, and one feature of the invention relates to applying the unit to the sounding board at a point spaced from one edge of the sounding board by a predetermined amount, depending on the thickness and texture of the wood.
  • Another feature relates to the provision of a plurality of difierently flexed sounding elements.
  • Fig. 1. is a sectional elevation' of one embodiment of the invention in which the sounding elements are flexedlongitudinally taken on the line 11 of Fig. 2;
  • D Fig. 2 is a horizontal section taken on the line 2-2 of Fig. 1;.
  • Fig. 3 is a side elevation of a modified form of the invention in which the sounding elements are flexed transversely;
  • Fig. 4 is a horizontal sectiontaken on the line H of Fig. 3;
  • Fig. 5 is a side elevation of a modified embodiment having four soundings elements each flexed transversely; g
  • Fig. 6 is a horizontal section taken on the line 66 of Fig. 5; l
  • Fig. 7 is a side elevation of,a modified form of the invention having four sounding elements each of which are flexed longitudinally;
  • Fig. 8 is a horizontal section taken on the line 8-8 of Fig. 7;
  • Fig. 9 is a side elevation of another 'modi
  • Fig. .10 is a horizontal section taken on the 'line 1010 of Fig. 9;
  • Fig. 11 is a side elevation of another modification of the invention in which two transversely flexed sounding-elements of unequal length are arranged at an acute angle with respect to each other;
  • Fig. 12 is a horizontal section taken on the line 1212 of Fig. 11.
  • a base 20 supporting four vertically extending ele ments 21, 22, 23, 24.
  • Two of the elements designated 21 and 22 respectively, are plain rectangular panels of wood provided merely for the purpose of support.
  • the other two elements 23, 24 are formed ofcarefully-kiln dried wood having all sap carefully removed to avoid fracturing the fiber and having its grain extending vertically.
  • Each sounding element 23, 24: is flexed longitudinally.
  • a top 30 is placed over the upper ed es of the elements 21, 22, 23, 24; and is provided on its lower face with a pair of depending brackets 31, 32 each having secured thereto an electromagnetic unit 33, 34. of the loud speakertype for converting undulatory electricalenergy into mechanical movement. It isunderstood that the units 33,34 are con- 'nected by conductors 35, 36 in circuit with a source of undulatory energy such as a radio receiving set, a phonographic Pickup device, a public address system or the like.
  • a source of undulatory energy such as a radio receiving set, a phonographic Pickup device, a public address system or the like.
  • the unit 33 actuates a link 37 serving as an operative connection to the sounding element 23, and the link 37 engages the respective sounding element at a point 38 which is approximately fifteen per cent of the total length of the free portion of the sounding element 23 from one of its edges, the distance depending upon the thickness and texture of the board.
  • the unit 34. includes a link 39 forming an operative connection with the sounding element 2 1 and is secured thereto at a point l0 which is also approximately fifteen per centof the total length of the free portion of the respective sounding element 24:.
  • the top 30 is apertured as at $1 and the bottom is apertured as at 42 for the emission of sound waves from the interior of the device.
  • the elements 51 and 52 correspond to the plane rectangular panels of wood shown as at 21, 22of Fig. 2 and are provided merely for the purpose of support.
  • the other two elements 53, 54 are formed of carefully kiln dried Wood having its grain extending vertically with respect to Fig. 3 and flexed transversely.
  • An electromagnetic unit 55 is provided for the vibratory element 53 being secured thereto by a link 56 engaging the sounding element at a point which is approximately 15% of the total length of the free portion of the sounding element from one of its edges.
  • a second electromagnetic unit 57 having a link 58 is similarly connected to the 05 op aosed sounding element 54.
  • Figs. 5 and 6 The embodiment of Figs. 5 and 6 is similar to that of Figs. 3 and 1: except that four transversely flexed sounding boards 61, (52, 63
  • Each sounding element Y is provided with an electromagnetic unit such as 65 having a link 66 operatively connected to the respective sounding element at a point which is approximately 15% of the total length of the free portion of the sounding elemenafronrone of its edges.
  • Figs. 7 and 8 The embodiment of Figs. 7 and 8 is similar to that of Figs. 1 and 2 except four longitudinally flexed sounding boards 71, 72, 7 3 and 74 are provided. Each is formedas in the embodiment of Figs. 1 and 2 and is provided with an electromagnetic unit such as 75 having a link 76. operatively connected to the respective sounding element at a point which is approximately 15% of the total length of A Thus it will beseen thatIhave provided a.
  • FIG. 9 four vertically eX- tion is therefore to be understood as not betending elements 81, 82, 83 and 84 are proing limited by the present specific descrip vided.
  • the elements 81, 82 are similar in tion. I intend no limitations other than construction to the sounding elements 58, 54 those imposed by the claims.
  • the other two elements 83, 84 are similar in construction to the elements 7 3, 74- and are rality of sounding boards flexed transversely,
  • a sound propagator comprising a pluconnected to the respective sounding element ralit f diff tly fl x d di b ard edges.
  • a sound propagator comprising a plu- In operation electrical undulatory e rgy rality of sounding boards flexed transverseis applied to the four electromagnetlc unlts ly, other sounding boards flexed longitudi- 1.
  • a sound producer comprising a plu as simultaneously and each causes vibration nally, said boards forming collectively a hol fectively in all directions.
  • each unit is provided with an electromagnetic unit such as 93, 93, each unit having a link such as 94 extending therefrom to the respective sounding element at a point which is approximately 15% of the total length of the free portion of therespective sounding element from one of its edges.
  • the sounding elements 91, 92 are shown as being flexed transversely, but it is understood that they may be flexed longi;

Description

Nov. 19, 1929 MJR. HUTCHI'YSON 7 1,735,860
FLEXED SOUNDING'BOAR'D Filed April 1. 1927 2 Sheets-Sheet -1 INVENTOR. Miller Reese Hufchison ATTORNEY NOV. 19, 1929. M R HUTCHISQN 1,735,86@
FLEXED SOUNDING BOARD Filed April 1, 1927 2 Sheets-Sheet INVEN TOR. Miller iFeese HuTch/son BY Q $46M A TTORNEY Patented Nov. 19, 1929' chiral) ESTATES PATENT OFFICE HUTCHISON, OF WEST ORANGE, NEW JERSEY, ASSIGNOR, BY MESNB ASSIGNMENTS, TO ACOUSTIC PRODUCTS COMPANY, OF NEW YORK, N. Y., A 003- ronurron or DELAWARE FLEXED SOUNDING IBQARD Application filed April 1,
This invention relates to the faithful reproduction of sound.
The invent' on has for its particular object the provision 'of-improved means for producing simultaneously musical notes having a wide range of frequencies, together with all the upper harmonics necessary for imparting quality or timber to music whereby the sounds of difierent musical character may be readily 1o identified. The. 'nvention has particular reference to a the reproduction of orchestral, band or chord music so that the sounds produced by the difierent instruments or voices of an ensemble are emitted in the same relative intensities as in the case of the original rendition of the music. i
Heretofore in the reproduction of such music by radio loud speakers and the like great difliculty has been experienced in obtaining even an approximation of bass notes.
It appearsthat this difiiculty is at least in part the result of impressing upon the ap ar-atus energy corresponding to the higher requencies of the musical register, and that when the apparatus is responding to such higher frequencies it does not faithfully respond to the energy of low frequency. This difliculty is not apparent when the apparatus is reproducin the bass notes singly as in the case of a ass solo, but develops immediately when the bass notes are to be produced at the same time as the notes of higher range.- Consequently it has been found with structures of the prior art that when proper response is obtained in the case of a bass sold, the response with an ensemble of instruments is not faithful and the bass notes are not properly balanced with the higher notes, so that the music is not always reproduced with fidelity.. g
In attempting to secure the proper balance which is desirable I have discovered that sounding elements" of wood operate well production of orchestral, band and choral music. In providing-such wooden elements, however, it is important to secure the proper relation between the dimensions of the element and to providemeans for flexing the under all the conditions obtaining in the re- 1927. Serial Ira-180,181. 7
formed of wood and to the provision of differently flexed elements, each having apredetermined configuration, in combination with means for impressing thereon vibratory energy.
The energy impressing means comprises generally an electromagnetic unit having an actuating element operatively connected to the respective sounding element, and one feature of the invention relates to applying the unit to the sounding board at a point spaced from one edge of the sounding board by a predetermined amount, depending on the thickness and texture of the wood.
Another feature relates to the provision of a plurality of difierently flexed sounding elements.
Other objects will appear from the following description taken in connection with the accompanying drawings in which Fig. 1. is a sectional elevation' of one embodiment of the invention in which the sounding elements are flexedlongitudinally taken on the line 11 of Fig. 2;
D Fig. 2 is a horizontal section taken on the line 2-2 of Fig. 1;.
Fig. 3 is a side elevation of a modified form of the invention in which the sounding elements are flexed transversely;
Fig. 4 is a horizontal sectiontaken on the line H of Fig. 3;
Fig. 5 is a side elevation of a modified embodiment having four soundings elements each flexed transversely; g
Fig. 6 is a horizontal section taken on the line 66 of Fig. 5; l
Fig. 7 is a side elevation of,a modified form of the invention having four sounding elements each of which are flexed longitudinally;
Fig. 8 is a horizontal section taken on the line 8-8 of Fig. 7;
Fig. 9 is a side elevation of another 'modi;
fication of the invention having four sounding elements two of which are flexed longitudinally and the other two transversely;
Fig. .10 is a horizontal section taken on the 'line 1010 of Fig. 9;
Fig. 11 is a side elevation of another modification of the invention in which two transversely flexed sounding-elements of unequal length are arranged at an acute angle with respect to each other;
Fig. 12 is a horizontal section taken on the line 1212 of Fig. 11.
Like reference characters denote like parts in the several figures of the drawing.
y In the following description and claims, parts, characteristic features and functions will be identified by specific means for convenience of expression, but they are intended to be as generic in their application to similar parts or equivalent construction as the art will permit.
Referring to Fig. 1 there is provided a base 20 supporting four vertically extending ele ments 21, 22, 23, 24. Two of the elements designated 21 and 22 respectively, are plain rectangular panels of wood provided merely for the purpose of support. The other two elements 23, 24 are formed ofcarefully-kiln dried wood having all sap carefully removed to avoid fracturing the fiber and having its grain extending vertically. Each sounding element 23, 24: is flexed longitudinally.
.A top 30 is placed over the upper ed es of the elements 21, 22, 23, 24; and is provided on its lower face with a pair of depending brackets 31, 32 each having secured thereto an electromagnetic unit 33, 34. of the loud speakertype for converting undulatory electricalenergy into mechanical movement. It isunderstood that the units 33,34 are con- 'nected by conductors 35, 36 in circuit with a source of undulatory energysuch as a radio receiving set, a phonographic Pickup device, a public address system or the like. The unit 33 actuates a link 37 serving as an operative connection to the sounding element 23, and the link 37 engages the respective sounding element at a point 38 which is approximately fifteen per cent of the total length of the free portion of the sounding element 23 from one of its edges, the distance depending upon the thickness and texture of the board. Similarly the unit 34. includes a link 39 forming an operative connection with the sounding element 2 1 and is secured thereto at a point l0 which is also approximately fifteen per centof the total length of the free portion of the respective sounding element 24:. The top 30 is apertured as at $1 and the bottom is apertured as at 42 for the emission of sound waves from the interior of the device.
In operation, undulatory electrical energy is transmitted over conductors 35, 36 to the units 33, 3 1 and causes longitudinal movement of the respective links 37 This movement is applied to the sounding elements 23, 24 causing them to vibrate accordingly. It is a charactertistic of a longitudinally flexed sounding element that it responds especially well to low pitched notes. It is in' effect a series of long parallel wood fibers extending longitudinally and responding to relatively low natural frequencies. Furthermore, by applying the vibratory energy near one end of the structure the center portion is oscillated to a greater degree producing vibrations of relatively large amplitude in the surrounding natural medium without excessive clearance between the armature and poles of the actuating unit. In the modified form of the .inventio shown in Figs. 3 and 4, four vertically extending elements 51, 52, 53 and 54 are provided. The elements 51 and 52 correspond to the plane rectangular panels of wood shown as at 21, 22of Fig. 2 and are provided merely for the purpose of support. The other two elements 53, 54 are formed of carefully kiln dried Wood having its grain extending vertically with respect to Fig. 3 and flexed transversely. An electromagnetic unit 55 is provided for the vibratory element 53 being secured thereto by a link 56 engaging the sounding element at a point which is approximately 15% of the total length of the free portion of the sounding element from one of its edges. A second electromagnetic unit 57 having a link 58 is similarly connected to the 05 op aosed sounding element 54.
n the operation of the embodiment shown in Figs. 3 and 4 electrical energy modulated in accordance with a signal current of complex wave form is applied to the units 55, 57
and causes longitudinal movement of the respective links 56, 58. This movement is communicated to the sounding elements 53, 54: causing them to vibrate accordingly; It is a characteristic of sounding elements of this 5 form to respond to notes of relatively higher pitch than those to which the longitudinally flexed sounding elements of the embodiment of Figs. 1 and 2 respond.
The embodiment of Figs. 5 and 6 is similar to that of Figs. 3 and 1: except that four transversely flexed sounding boards 61, (52, 63
and 64 are provided. Each sounding element Y is provided with an electromagnetic unit such as 65 having a link 66 operatively connected to the respective sounding element at a point which is approximately 15% of the total length of the free portion of the sounding elemenafronrone of its edges.
In operation electrical undulatory energy volume of sound emitted in all directions with substantially equal intensity is thus obtained.
The embodiment of Figs. 7 and 8 is similar to that of Figs. 1 and 2 except four longitudinally flexed sounding boards 71, 72, 7 3 and 74 are provided. Each is formedas in the embodiment of Figs. 1 and 2 and is provided with an electromagnetic unit such as 75 having a link 76. operatively connected to the respective sounding element at a point which is approximately 15% of the total length of A Thus it will beseen thatIhave provided a.
sound propagator formed of a cellular material, flexed in varying combinations to produce music of improved quality. The cellular texture of the material, and the flexure of the material greatly improves the quality of the free portion of the respective sounding \the sound By providing sounding elements fixed in different planes brilliant as well as I element from one of its edges.
In operation electrical undulatory energy mellow sounds are effectively produced thus is applied to the four electromagnetic units increasing the attractiveness of the music to a simultaneously and each causes vibration great extent. a
of the associated sounding element in accord- The invention upon which this application ance with the signal wave. A larger volume is based is broader than the specific embodiof sound, of low pitch is thus transmitted ment shown and described for the purpose of effectively in all directions. illustrating at least one of the ways in which In the modified form of the invention it'may be employed. The scope of the inven-.
shown in Figs. 9 and 10 four vertically eX- tion is therefore to be understood as not betending elements 81, 82, 83 and 84 are proing limited by the present specific descrip vided. The elements 81, 82 are similar in tion. I intend no limitations other than construction to the sounding elements 58, 54 those imposed by the claims.
of Figs. 3 and 4 and are flexed transversely. What is claimed is:
The other two elements 83, 84 are similar in construction to the elements 7 3, 74- and are rality of sounding boards flexed transversely,
flexed longitudinally. I other sounding boards flexed longitudinally, Each of the four sounding elements 81, 82, and means forvibrating all of said boards 83 and84 is provided with an electromagnetic imultaneou ly.
unit such as 85 having a link 86 operatively 2. A sound propagator comprising a pluconnected to the respective sounding element ralit f diff tly fl x d di b ard edges.
at a point which' is approximately 15% of forming a hollow chamber and a correspondthe total length of the tree portion of the re ing plurality of operating units for actuatspective sounding element from one of ltS ing said boards respectively. x 3. A sound propagator comprising a plu- In operation electrical undulatory e rgy rality of sounding boards flexed transverseis applied to the four electromagnetlc unlts ly, other sounding boards flexed longitudi- 1. A sound producer comprising a plu as simultaneously and each causes vibration nally, said boards forming collectively a hol fectively in all directions.
of the associated sounding elementin accordlow chamber, and means for actuating said ance with the signal wave. A larger volume b -dg i lt l of sound, of low pitch is thus transmitted ef- York and State of New York, this 30th day of In the modified form of the inventlon M h A, D 1927,
shown in Figs, 11 and 12 two elements 91, 92,
positioned at art acute angle with respect to one another. Each is provided with an electromagnetic unit such as 93, 93, each unit having a link such as 94 extending therefrom to the respective sounding element at a point which is approximately 15% of the total length of the free portion of therespective sounding element from one of its edges. In the drawing the sounding elements 91, 92 are shown as being flexed transversely, but it is understood that they may be flexed longi;
tudinally asdiselosed in Figs. 7 and 8, or one may be flexed transversely and the other flexed longitudinally as in the combination shown in Figs. 9 and 10.
In the operation of the modified form of I the invention of Figsll and 12 electrical undulatory energy is applied to the two electromagnetic units 93 simultaneously and each causes vibration of the associated sounding element in accordance with the signal wave. Musical sound of improved quality is thus produced.
Signedat New York, in the county of New MILLER REESE HUTOHISON.
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Cited By (10)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3107746A (en) * 1960-04-29 1963-10-22 Namon Richard Speaker design
US3239029A (en) * 1960-04-29 1966-03-08 Namon Richard Speaker design
US3247925A (en) * 1962-03-08 1966-04-26 Lord Corp Loudspeaker
US3980829A (en) * 1973-06-05 1976-09-14 Harold Norman Beveridge Wide angle cylindrical wave loudspeaker extending approximately from floor to ceiling height with a lens
US3985201A (en) * 1974-10-24 1976-10-12 Kloster Glenn R Infinite sound reproduction chamber
US4473721A (en) * 1981-04-01 1984-09-25 Siegfried Klein High-frequency loud speaker
US4903308A (en) * 1988-02-10 1990-02-20 Linaeum Corporation Audio transducer with controlled flexibility diaphragm
US5198624A (en) * 1988-02-10 1993-03-30 Linaeum Corporation Audio transducer with controlled flexibility diaphragm
US6061461A (en) * 1998-05-08 2000-05-09 Paddock; Paul W. Audio transducer
US6904154B2 (en) 1995-09-02 2005-06-07 New Transducers Limited Acoustic device

Cited By (14)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3107746A (en) * 1960-04-29 1963-10-22 Namon Richard Speaker design
US3239029A (en) * 1960-04-29 1966-03-08 Namon Richard Speaker design
US3247925A (en) * 1962-03-08 1966-04-26 Lord Corp Loudspeaker
US3980829A (en) * 1973-06-05 1976-09-14 Harold Norman Beveridge Wide angle cylindrical wave loudspeaker extending approximately from floor to ceiling height with a lens
US3985201A (en) * 1974-10-24 1976-10-12 Kloster Glenn R Infinite sound reproduction chamber
US4473721A (en) * 1981-04-01 1984-09-25 Siegfried Klein High-frequency loud speaker
US4903308A (en) * 1988-02-10 1990-02-20 Linaeum Corporation Audio transducer with controlled flexibility diaphragm
US5198624A (en) * 1988-02-10 1993-03-30 Linaeum Corporation Audio transducer with controlled flexibility diaphragm
US6904154B2 (en) 1995-09-02 2005-06-07 New Transducers Limited Acoustic device
US20050147273A1 (en) * 1995-09-02 2005-07-07 New Transducers Limited Acoustic device
US20060159293A1 (en) * 1995-09-02 2006-07-20 New Transducers Limited Acoustic device
US7158647B2 (en) 1995-09-02 2007-01-02 New Transducers Limited Acoustic device
US7194098B2 (en) 1995-09-02 2007-03-20 New Transducers Limited Acoustic device
US6061461A (en) * 1998-05-08 2000-05-09 Paddock; Paul W. Audio transducer

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