US1174812A - Electromagnetic piano. - Google Patents

Description

' G. BREED.

ELEcmoMAGNEnc PIANO.

APPLICATION FILED MAR. 20, 1912.

Patented Mar. 7, 1916.

2 SHEETS-SHEET l.

G. BREED.

ELECTROMAGNETIC PIANO.

APPLICATION FILED MMI` 2o, I9I2.

2 SHEETS-SHEET 2.

fw I ff UNITED STATES PATENT OFFICE.

GEORGE BREED, OF PHILADELPHIA, PENNSYLVANIA, ASSIGNOR T0 LYRACHORD COMPANY, A CORPORATION OF NEW YORK.

ELECTROMAGNETIC PIANO.

State of Pennsylvania, have invented a newl and useful Electromagnetic Piano, of which 'the following is a specification.

This invention is an electromagnetic musical instrument having improved tone producing and sustaining mechanism combined in a. hammer piano adapted to be operated manually, by means of the usual keys, or mechanically, by means of the usual pneumatic mechanism. ,i

Characteristic improvements of my invention reside in its means whereby. the performer is able, at will, to draw from the instrument the tones produced by the hammers alone, sustained tones of the desired volume produced by the electro-magnets alone, or the desired blending of such tones either by the operationof the keys or the pedals of the instrument.

The improved features of my invention are fully disclosed in the following description and the accompanying drawings in illustration thereof. v

On the accompanying drawings, Figure 1 is a sectional elevation of a piano embodying my invention. Fig. 2 is a diagrammatic, part sectional, View illustrating a unit of my improvements, and Fig. 3 is a detail view illustrating features of the mechanism for varying the electro-magnetic action. i The mechanism, as illustrated in the drawings, comprises a set of the usual musical strings 1, hammers 2, and dampers 3 carried by the rail 4, wippens 5 fulcrumed with relation to the rail 4, abstracts 6, jacks 7 and springs 8 through which the wippens ,5 act upon the hammers 2 and dampers 3,

respectively, keys 9 which act through the abstracts 6 to rock the wippens 5, and flexible fingers 10 'whichcan be rocked to operate the wippens 5 by rods 11. through the action thereon of\ bellows or pneumatics 12, which are connected to the Wind-trunk 13 fromwhich the air is exhausted by' the bellows 14 operated by treadles.

The wind-trunk 13 is provided with a Specification of Letters Patent.

.rail and magnets thus'forming a unitary- Patented Mar.'7, 1916.

Application filed March 20, 1912. Serial N o. 684,922.

reservoir or storer 130 and is connected by passages to valve boxes 131 on which the pneumatics 12 are carried. The pneumatics are called into operation from a perforated note-sheet 132 which is drawn from a music spool 133 over a tracker bar 134 and wound on a take-up spool 135. These parts are arranged so that the instrument can be played either automatically by the pneumatic mechanism, or manually by the keys 9.

Arranged in front of each string which is to be operated electro-magnetically, is an electro-magnet 15 (Fig. 2) made U-shaped and provided with a coil 15 preferably only on one arm, which arm has threaded therethrough a metallic core 15 by which the relation of the end of the pole can be adjusted relatively to the string. The electromagnets are supported in a rail 16 by embedding them in insulating material 16', the

structure which can be easily placed in position, in which individual adjustments can be made, and by which construction the parts are not liable to derangement.

Each magnet is in a circuit comprising a conductor 17 (containing a switch 18) connected with a'battery 19, or other source of electrical energy, a conductor 2O connecting the battery with a conductor 21 having coils 21', a contact 22 engaged to the coils 21', a resilient conductor 23 having coils 23, a contact 24 engaged in the coil 23 and adapted to engage the contact 22, a tine wire 25 connecting the conductor 23 with the end of a resilient conducting loop 26, a conductor 27 connecting the loop 26 with the resilient contact 28, a resilient contact 29 with which the contact'28is adapted to engage and conductor 30 connecting the contact 29 with the electro-magnet 15 4and thus completing theV tacts 32 and connected at its other end with a resilient contact 39, a conductor 40, connecting the conductor 17 with a resilient contact 41, a resistance coil 42, connecting the contact-,'41 with a resilient contact 43,

a resistance coil 44, connecting the contact l 43 with a resilient contact 45, and a movable vbridge 46 adapted for connecting the contacts 39, 41, 43 and 45, for cutting out the contacts 41 and 43 in succession so as to cut in the resistances 42 and 44 in succession and for breaking communication between the contacts 39 and 45 so as to cut out the shunt circuits.

The contacts 39, 41, 43 and 45 are fixed to ablock 47 which is provided with an arm 47 (Fig. 3) and which is connected by ahinge 48 to a support 49. A spring 49 acts on the block to hold the contacts in engagement with the bridge 46, and' a rod 50, operated by a button 50, acts on the arm 47 to effect the withdrawal of the contacts from the bridge and cut out the shunt circuits. The bridge 46 is fixed on a cylinder 51 which is secured on a journaled shaft 52. The latter acts through a crank 53 and link 54 on an-arm 55 by which the hammer rest rail 56 is turnedon its bearings 57 An arm 58 is fixed on the shaft 52 and connected withl a spring 59, secured to a fixed part, whereby the connected parts are normally held in the position shown. A rod 60, provided with a button 60, acts on an arm 61 which is fixed to the shaft 52 eccentrically to the cylinder 51, and a rod 62, operated by pedal 63, acts on the pin 64 mounted on a crank arm xed to the shaft 52 and also eccentric to the cylinder 51. The shaft 52 may acf cordingly be moved either by means of the button 60 or by the pedal 63 to change the positin of the bridge 46 relative to the contacts 39, 41, 43 and 45, and such movement of the shaft through the arm 53 and the link 54 will simultaneously change the position of the hammer rest rail 56. `When the shaft 52 is moved by the button 60 or by the pedal 63 to increase the resistance in the shunt circuit and thus increase the intensity of the electromagnetic effect, the arm 53 draws the rod 54 downward, thus retracting the hammer rest rail 56. This permits a longer stroke of the hammers which is the usual and well known method of mechanically increasing the intensity of the effect of the hammer actions. Hence the stroke ofeach hammer and the electromagnetic eect on the string operated therebyv are correlated.

rIhe pulsators, (each comprising the parts 21, 22, 23, 24, 25 and 26), are supported by a rail comprising sections 65 and 65y (preferably of wood), between which the parts 21 are clamped and properly insulated, the,

spring 23 being connected by bracket 66 to the part 65 and the spring 26 being connected to the part 65 by the adjusting screw 67, whereby the tension of the wire 25 and the consequent regulation of the pulsators ac- '1 and pulsating string 71, the end of the string 74 being secured to a button 75 which is adjustable and held by friction on the string 71.

0f course, there is an electro-magnet, a y

circuit. controlling device, and a pulsator for each string which is to be operated electromagnetically, and the conductors can be conveniently arranged by wiring the set of mag-- nets in multiple arc from po-int a, connecting each magnet to the member 29 of its circuit controlling device by an additional conductor 30, connecting each member 28 of each circuit controlling device to its pulsator by an individual conductor 27, and by connecting the pulsators to a common return conductor b.

It also will be noticed that when the abstract is elevated, the contacts 28 and 29 are first brought together and then the contact 29 is brought against the contact 32. By this arrangement, the full current will be sent for an instant through the electro-magnet and pulsatorbefore the shunt circuit is closed, whereby the pulsator will be started in full vibration at the beginning of the operation.

ylln operation, when the switch 18 is open, the electro-magnetic action is disconnected and the tones are produced by the usual hammer actions, either manually or pneumatically. thebridge' 46 in position for directly connecting the contacts of the circuits controlled thereby, upon elevating an abstract (whether by the direct action of a keyv 9 or the indirect With theswi'tch 18 closed and action of a pneumatic 12)O the block 35 will effect the engagement of the contact 28 with the contact 29, thereby closing the main circuit containing the electro-magnet 15 and battery 19.

The electro-magnet being excited by the current nowflowing therethrough, the string current, and the desired phase relation beu tween the vibration of the string 1 and the pulsations of the current being effected by the adjustment of the string 71.

I f an abstract be elevated, so as to effect additionally the engagement of the contacts 29 and 32 while the contacts 39 and 4l are connected by the bridge 46, part Iof the current otherwise passing through the corresponding electro-magnet will flow through the shunt circuit containing these contacts, the electro-magnet receiving a reduced portion of the current, (depending upon the shunt circuits resistance), and the string 1 consequently producing a softer tone. As the cylinder 51 can be turned so as to disengage r engage the bridge 46 with relation to the contacts 41 and 43 and thus cut in or out one or both of the resistances 42 and 44, the current passing through theshunt circuit and the electro-magnet can be varied in inverse ratio with resulting variation in the tone. by pushingl the button so as to tilt the block 47, the contacts carried thereby are disengaged from the bridge, the shunt circuit is broken, the maximum current is passed through the electro-magnet and the maximum tone is produced.

The buttons are used principally when the instrument is being operated automatically through the pneumatic mechanism. During this operation, the full or most powerful electro-magnetic effect can be obtained by pressing down upon the button 50', while a graduated effect can be 0btained by pressing down more or less on the button eo.

The button 50 may beprovided with a bayonet slot to coperate with a pin so that it can be retained in its lowered position when it is desired to play with theV full electro-magnetic effect. The buttons are preferably placed on the front ledge of the piano casing on which the devices for-controlling the operation of the pneumatic mechanism are ,also usually arranged.

llhen the instrument 'isv'to be played manually, these buttons are commonly covered by the fall lboard of the casing and the electro-magnetic effect is then controlled by means of the pedal 63, the operation of which controls the shunt circuit and also moves the hammer res't rail away from the wires permitting the hammers to move backward so that they will have an extended sweep or blow, whereby the increase in the electro-magnetic eiect will be correlated with the increase of the hammer blow. |The link 62 which engages the pin 64 is slotted and constitutes a lost motion connection, permitting the cylinder 51 to be operated by the button independently of the pedal 63.

By the arrangements described, the electric mechanism ishoused in the piano casing the button 50 It will be understood that` in position to coperate with the strings and instrumentalities therein without adding to the size of the casing and without effecting said mechanism. All that is necessary is to provide a suitable source of electrical energy for the conductors 17 and 20, which conductors may be led to a source of electricity outside of the piano if desired.

By operating the hammers very lightly, sounds can be produced resembling inefi'ect organ playing, as the electro-magnetic effect will overpower the hammer effect and indeed in this operation, as the hammer rail 56 is not retracted, the hammers can be operated so lightly that the ordinary hammer eect will be entirely eliminated. During such operation the electro-magnetic effect may be intensified if desired by depressing to cut out the shunt circuit.

Again, by proper use of the button 60', the instrument can be played with a combination hammer and electro-magnetic effect, something like an organ and piano combined, and the loudness or softness of this combination can be varied in a correlated manner. When the button 60 is pressed down to increase the electro-magnetic effect, the hammer rail 56 is retracted t0 increase the hammer effect. Also a swell in the electro-magnetic or organ effect can be obtained by manipulating the buttons after the hammers have struck, and by opening the switch 18, the instrument may be played entirely with a hammer effect. Thus by suitably manipulating the pedals and buttons, Very remarkable and novel effects may be obtained.

The above mechanism for controlling the electromagnetic action can also beapplied to pianos having a hammer rest rail made in a plurality of sections and when this is done, l prefer to use separate and controlling mechanism of the nature above described, for each section of the hammers, as defined by the sections of the hammer rest rail.

rlhe details and arrangements herein shown and described may be greatly Varied by a skilled mechanic without departing from the scope of my invention as expressed in the claims.

. r1`herefore, having described my invention, what 1 desire to secure by Letters Patent 1s 1. 1n a piano, the combination of the strings, keys and hammers, means controlled by a note-sheet for operating the hammers automatically independently of the keys, electro-magnetic mechanism for vibrating the strings, and connections between the hammer-operating mechanism and the electro-magnetic mechanism whereby when a hammer is operated either manually or automatically its string will be yibrated by the electro-magnetic mechanism.

` 2. 1n a piano, 'the combination of the from the hammer operating means and eiective, when a hammer is operated either manually or automatically, to energize the magnet coperating with the corresponding string.

3. In a piano, the combination of the strings and hammer actions, pneumatics con trolled by a note-sheet for operating the ac.

tions automatically, a set of electro-magnets for vibrating the strings, and circuit controlling devices therefor operated from the labstracts of the hammer actions.

4. In a piano, the combination of the strings, keys and hammer actions, means controlled by a note sheet for operating the actions independently of the keys, a set vof electro-magnets for vibrating the strings, a circuit including said magnets, and devices effective to control the ioW of current through said circuit whereby the piano may be played automatically by the hammer actions only or With an electro-magnetic effect in addition thereto.

5. In a piano, the combination of the strings and hammer actions, keys for operating the actions, means controlled by a note sheet for operating the actions automatically, electro-magnetic means for vibrating the strings, a circuit including said electromagnetic means, and devices for controlling the flow of electricity in said circuit, thereby permitting the piano to be played either manually or automatically by the hammer actions only when the circuit is open or with a combined hammer and electro-'magnetic effect When the circuit is closed.

6. In a piano, the combination of the strings, keys and hammer actions, a set of electromagnets for` vibrating the strings, a circuit including said electromagnets, and

devices for controlling the `flow of electricity in said circuit, said parts being so connected that the piano can be played with a combination hammer and electro-magnetic ciect,

and means independent of the keys for ini I creasing or decreasing the intensity of the hammer and electro-magnetic effect simultaneously.

7. Inga piano, the combination of the strings, keysy and hammer actions, means controlled by a note sheet for operating the actions automatically, a set of electromagnetsfor vibratingthe stringsa circuit in-,. cludmg said electromagnets, devices for controlling the flow of current in said circuit, Vsaid part'sbeing so connected that the piano can be played with a combination hammer and electro-magnetic effect, and means inde-V pendent of the keys by which the intensity of the hammer stroke and of the electromagnetic eliect can be increased or decreased.

8. In a piano, the combination of the strings and hammer actions, keys for operating the hammer actions, means controlled by a` note sheet for operating the actions automatically, a set of electromagnets for vibrating the strings, a ciruit including said electromagnets, devices for controlling the flow of current in said circuit, said parts and devices being eiiective' to permit the piano to be played either manually or automatically With a combined hammer and electro-magnetic effect, and means independent of the keys effective to increase or decrease the intensity of the hammer stroke and of the electro-magnetic effect simultaneously.

9. In a piano, the combination of the strings and hammer actions, aset of electromagnets for vibrating the strings, a main circuit including a source of electricity, a branch circuit for each of said electromagnets, a shunt circuit for each branch circuit connected in paralllel With-each branch vcircuit andei'ective when closed to reduce the current flowing through the branch circuit, and circuit closing devices e'ective, when the hammer isloperated, to close the branch circuit through the corresponding magnet and the shunt circuit in parallel with said branch circuit successively, Whereby the magnet Will trolled.

10. In a piano, the combination of the strings and hammer actions, a set of electromagnets for vvibrating the strings, 'a main circuit including a source of electric- `ity, a branch circuit for each of said elec-V ,tromagnets for vibrating the strings, a main circuit including a source of electricity, a branch circuit for each of said electromagnets, a shunt circuit for each branch circuit connected in parallel With each branch circuit and effective When closed to reduce be energized and conthe currentJ flowing through the branch circuit, circuit closing devices effective when a hammer is operated to close the branch'.

circuit through the corresponding magnet and the shunt circuit in parallel with said branch circuit successively, whereby the magnet will be energized, and means for varying the resistance in the shunt circuit.

12. In a piano, the combination of the strings and hammer actions, a set of electromagnets for vibrating the strings, a main circuit including a source of electricity, a branch circuit for each of said electromagnets, a shunt circuit for each branch' circuit connectedin parallel with each branch circuit and edective when closed to reduce the current flowing through the branch circuit, circuit closing devices 'edective when a hammer is operated to close the branch circuit through the corresponding magnet and the shunt circuit in parallel with said branch circuit successively, vwhereby the magnet will be energized, and means for breaking the shunt circuit and for varying the resistance therein.

13. In a piano, the combination of thel strings and hammer actions, a set of electromagnets for vibrating the strings, a main circuit including a source of electricity, a branch circuit for each of said electromagnets, a shunt circuit for each branch circuit connected in parallel with each branch lcircuit and effective when closed to reduce the current flowing through .the branch circuit, circuit closing devices effective when a hammer is operated to close the branch circuit through the corresponding magnet and the shunt circuit in parallel with said branch circuit successively, whereby the .magnet will be energized, a movable bridge arranged in said shunt circuit, a series of contacts coperating therewith, resistances arranged between said Contacts, and means for movingsaid bridge whereby the resistance of the shunt circuitmay be varied.

' 14. In a piano, the combination of the strings and hammer actions, a set of electromagnets for vibrating the strings, a main circuit including a source of electricity, a

branch circuit for each of said electromag-- nets, a shunt circuit for each branch circuit connected in parallel with each branch circuit and effective when closed to reduce the current flowing through the branch circuit, circuit closing devices eective when a hammer is operated to close the branch circuit through the corresponding magnet and the shunt circuit in parallel with said branch circuit successively, whereby the magnet will be energized, a movable bridge arranged in said shunt circuit, a series of contacts cooperating therewith, resistances arrangedbetween said contacts, means for moving said bridge whereby the resistance of the shunt circuit may be varied, and means for moving the contacts away from the bridge to break the shunt circuit.

15. In a piano, the combination of the current flowing through said branch circuit,

and circuit controlling devices effective to control the flow ofcurrent in the shunt circuit and also connected to vary the intensity of the stroke of the hammer actions.

16. In a piano, the combination of the.,

strings and yhammer actions, a set of electro.

magnets for vibrating the strings, a main circuit including a source of electricity, a branch circuit foreach of said electromagnets, a shunt circuit for each branch circuit connected in parallel with said branch circuit and effective when closed to reduce the current flowing through said branch circuit, and circuit controlling devices effective to control the flow of current in the shunt circuit andalso connected to vary the intensity of the stroke of the hammer actions simultaneously with variations in the flow of current in the shunt circuit.

17. In a piano, the combination of the strings and hammer actions, keys for operating the hammer actions, means controlled by a note sheet for operating the hammers automatically, a set of electromagnets for vibrating the strings, a main circuit including a source of electricity, a branch circuit for each of said electromagnets, a shunt circuit for each branch circuit connected in parallel with -said branch circuit and effective when closed to reduce the current flowing through said branch circuit, and circuit controlling devices elective to vary the intensity of the stroke of the hammer actions .and the effect of the-electromagnets simultaneouslywhile the piano is being played either manually or automatically.

18. In a piano, the combination of the strings and hammer actions, keys for' operating the hammer actions, means controlled by a note sheet for operating the-hammers automatically, a set of electromagnets for vibrating the strings, a main circuit including a source of electricity, a vbranch circuit for each of said electromagnets, a shunt circuit for each branch circuit connected in parallel with said branch circuit and effective when closed to reduce the current flowing through said branch circuit, and circuit controlling devices eective to vary the intensity of the strokey of the hammer actions and the effect of the electromagnets simultaneously while the piano is being played either manually or automatically, said devices including a button connected and eeective to change the resistance of the shunt circuit and to vary the position of the hammers when the instrument is played automatically, and a pedal connected and effective to vary the position of theham- -mers and to change the resistance of the shunt circuit when the instrument is played. manually.

19. In a iano, the combination of the 'strings and ammer actions, keys for operating the hammer actions, means controlled by a note sheet for operatingv the hammers automatically, a set of electromagnets for vibrating the strings, a main circuit including a source of electricity, a branch circuit for each of said electromagnets, a shunt circuit connected in parallel with said branch circuits and effective when closed to reduce the flow of current flowing through the branch circuit, circuit controlling devices effective to close one branch circuit and the correspondingl shunt circuit to energize one of said magnets when a hammer is operated, and means elective to control the flow of current through the shunt circuit after the hammer has been operated thereby producing a varying electromagnetic ei'ect.

20. In a piano, the combination of the strings and hammer actions, a set of electromagnetsfor vibrating the strings, a set of pulsators mechanically connected to the strings and each electrically connected in Vseries with one of said electromagnets, a

main circuit including a source of electrlcity, a branch circuit for each electromagnet and associated pulsator, a shunt circuit for each branch circuit connected in parallel with said magnet and effective when closed to reduce the currentI flowing through said magnet, and circuit closing devices effective when a hammer is operated to close the branch circuit through the corresponding magnet and pulsator and also toclose the associated shunt circuit, whereby the magnet will be energized andthe pulsator -opf erated.

2l. In a piano, the combination ofv the strings and hammer actions, a set of electromagnets for vibrating the strings, a set of pulsators mechanically connected to the strings and each electrically connected in series with one of said electromagnets, a main circuit including asource of electricity, a branch circuit for each electromagnet and associated pulsator, a shunt circuit for each branch circuit, connected lin parallel with said magnet and 'eective when closed to reduce the current iowing through said magnet, circuit closing devices effective when a hammer is operated to close the branch circuit through the corresponding magnet and pulsator and also to close the associated shunt circuit, whereby the magnet will be energized and the pulsator operated, and'means effective to break the shunt circuit, l

22. In a piano, the combination of the strings and hammer actions, a set of electromagnets for vibrating the strings, a set of pulsators mechanically connected to theV strings and eachelectrically connected in series with one of said electromagnets, a

main circuit including a source of electricity, a branch circuit for each electromagnet and associated pulsator, a shunt circuit for each branch circuit connected in parallel with said magnet and effective when closed'to reduce the current fiowing through said magnet, circuit closing devices f effective when a hammer is operated to close the branch circuit through the correspondingmagnet and pulsator and also to close the associated shunt circuit, whereby the magnet will be energized and the pulsator operated, and means effective to vary the resistance in the shunt circuit.

23. In a piano, the combination of the strings and 'hammer actions, a set of electroeffective when a hammeris operated to close the branch circuit through the correspondp ing magnet and pulsator and also to close the associated shunt circuit, whereby the magnet will be energized andthe pulsator operated, and means effective to break the shunt circuit or to vary the resistance therein.

24. In a piano, the combination of the strings and hammer actions, a set of electromagnets for vibrating the strings, a main circuit including a source of. electricity, a

branch circuit for each of said electromag- 7 nets, a shunt circuit Jfor "each branch circuit connected in parallel therewith and eilective when closed to reduce. the current flowing through the branch circuit, and circuit closing devices effective when a hammer is op- 1 erated to first complete the branch circuit through the corresponding magnet to thereby energize the magnet and to thereafter close the corresponding shunt circuit.

25. In a piano, the combination of the strings and hammer actions, a set of electromagnets and pulsators for vibrating thestrings, a main circuit including a source of electricity, a branch circuit for each electromagnet and associated pulsator, a shunt circuit for each branch circuit connectedvin parallel with said magnet and effective when closed to reduce the current iowing through finali-,sia

10 casing, Within which rail said magnets are embedded in an insulating material forming therein a substantially unitary structure.

ln testimony whereof l have hereunto set myha-nd7 in the presence of two subscribing Witnesses.

GEORGE BREED.

Witnesses:

W. E. RAMMELKAMP, ROBERT L. STOTESBURY.

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