US1253744A - Musical instrument. - Google Patents

Musical instrument. Download PDF

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US1253744A
US1253744A US47147109A US1909471471A US1253744A US 1253744 A US1253744 A US 1253744A US 47147109 A US47147109 A US 47147109A US 1909471471 A US1909471471 A US 1909471471A US 1253744 A US1253744 A US 1253744A
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valve
board
pneumatic
chamber
diaphragm
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US47147109A
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Charles F Stoddard
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Charles F Stoddard
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    • GPHYSICS
    • G10MUSICAL INSTRUMENTS; ACOUSTICS
    • G10FAUTOMATIC MUSICAL INSTRUMENTS
    • G10F1/00Automatic musical instruments
    • G10F1/02Pianofortes with keyboard

Description

C. F. STUARD.

MUSICAL INSRUNmNT Awmmfon NLE!) JAN. 9, 909.

1,253,74Lf-1L. Patented Jan. 15, 1918.

2 SHEETS-SHEET 2,

JEL/9. a.

` CHARLES 4F.,S'101D1)A1HD, 0F DQSTON, MASSACHUSETTS MUSICA-L INSTRUMENT.

To all whom it 'may concern.' y Be it known that I, CHARLES F. Sropnnnu, a citizen of the United States, residing at Boston, in the county of Sulfolk and (Jommonweal-th of Massachusetts, have invented an Improvement in Musical Instruments, of which the following description, in connecn tion with the accompanying drawings, is 'a specification, like letters on the drawings i representing like parts.' v

This invention relates to pneumatic musical instruments; and pertains more particularly to improvements in construction whereby the part-s of such an instrument may be assembled in convenient compact form,

vand may be4 thoroughly responsive and eth- Vcient in operation. Certain ,jeatures of the invention pertain alsoto structural improvemeuts'which contribute strength and stabil-y ity to instruments of the character described.

The invention may be best understood by reference to a specific illustrative' embodi- 4 -ment thereof-shown, merely by way` of exinafter described;

jemplification, inthe accompanying draw- Figure 1 is a'diagrammatic .view of an action showing a Iseries of motor-pneumatics in section on a linel-V-l of Fig. 6;-

Fig. 2 is an .enlarged detailof certain partsV shown in Fig.1; the plane of section is-on the line 2-2 of Fig. 3;

Fig.3 is a plan .view ofV two motor-pneullnatics partly in section on ,a'lineB- of Fig. 4 is a 'detail bottom plan view of part of a motor-pneumatic valve mechanism heire-v Fig. 5 is a detail front elevation (viewed from the right in Fi'.; 1) oflthe tiers of motorfpneumatics; an Y Fi`g 6 is a detail rear elevation of the tiers of 4'motor-.pneumatics viewed from the' lef-t Re erring now to Fiv`g.1.-there is shown a key A which, `.vvhen struck, elevates a 4a thelatter to stri y e-a-string D, Aatthe same .i i time withdrawing from the string a'dam so f per IE. i'

Instead of beingactuatedv through 'the key A, the hammer action. may have applied to 'f its wippen F` a sticker Grl controlled by a idle) open toatmosphere.

invention, is of importance.

hammer C and causing Specictvion of Letters Patent.' Patentd J all. 15, 191.8.V Application led January 9, 1909. .Serial No. 471,471. I i

motori-pneumatic H. The speci-flicM motor' pneumaticH illustrated in Fig. 1 is normally (when its corresponding hammer is the pneumatic H is closed to atmosphere and opened to the tension or'suction in the windchest which 'collapses the-pneumatic H, and thereby elevates'the sticker G, rocks the wippen' F and operates the hammer action for striking the Istring DQ The construction ofV the motor-pneumatic H, as exempliyinggcertain features of this When desired,

It has been customary heretoforeto asso,n

ciate with a motorpneumatic a secondary valve for-control 'wayor another, the operation ofjthe pneu matic. So far as I amatpresent advised, such primary` and secondary.'V valvesl have been, at least in a large measure,.structurally separate from the pneumatic itself, thereby necessitating a more or less bulky structure to accommodate theydifferenseparateparts. It is one of the objects of thls invention, so to assemble a motor-pneumatic and its con trolling valve mechanism, as to admit of an extremely compact arrangement. This obprimary and ng, in' one l ject may be conveniently and practicablly veffected by the construction shown in Fig.

For illustration, the Yuma'tic H -is represented as' being under the ultimate control of aftracker 6 coperating with the usual perforated 4note sheet (not shown).` Thel tracker 6 may'have-the usual vents, one for .each note.4 A vent 7, for instance, may lead to af dulct 8 which communicates withla' diaphragm chamber 9 to which atmosphere isadmitted Whenever a erforation of the note sheet' registers with t e vent 7. `Atmosphere in the chamber 9 distends its diaphragm and thereby elevates a duplex primary valve 11, the oflice of which will be described presently. y

The board 13, in which the diaphragm chamber 9` may be formed',is so vrelated to Vtheopposed board 14, that therentervenes between themen exhaust chamber 16. Referring to Fig. `4, the exhaust chamberl isY preferably in constant communication with a Wind-trunk 17, which' in turn com` municates with themain wind-chest which may be 'exhausted irl-any practicable manner, as by any o f the means already known loo vided, preferably by means oi' a recess in the top board 14, a diaphragm chamber. 19, having a duct 20, which leads to a port controlled by the primary valve 11. Preferably' secured to the diaphragm of the chamber 13 (as by being cemented thereto) .is a valvegoi-'erning device exemplified by a depending stem In position to coperate with the stem 21, but preferably not actually connected thereto, is a motor-pneumatic governing valve The valve may coperate with the stem 21., or its equivalent, through the agency of a block 25, which maybe cupped or otherwise constructed partiallytoembrace the end of the stem 21. It is preferred, at least with thc-specilie arrangement shown, that the block 25 have a substantially truste-conical recess to receive the stem 21, so that when said stem is moved toward the block or vice versa, the two will tend to center themselves and register automatically.

Cooperation between the stem 21, or its equivalent or substitute, and the valve 23,`

may be contributed to effectively by providing some means to apply a yielding force to the opposite side of the valve 23 from the stem 21. For instance, a light coil spring 27 may be interposed between the face of the valve 23 and a bridge 28, shown in Figs. 1,- 2 and 4, as extending across, but not closing,

`the outlet port 'through the movable bellowsboard.

The motor-pneumatic H may have a sta tionary board 30 fixed to the under side of the board 13; and a movable board 32 hinged in any practicable manner to the stationary board 30.

A passage 34 may lead from the exhaust chamber 16 to the interior of the pneumatic H; and the passage may be closed, as occasion requires, by means of the valve 23. The seat for thev valveI 23 preferably lconsists tof-'ian annulus 35 of felt, chamois, or the like, for deadening the sound of impact of the valve 23 and to supply a tight closure in coperation with the valve; and the annlus 35 preferably encircles the' passage 34 and may be eountersunk in the inner face of the stationary bellows board 30.

The movable bellows board 32 of the pneumatic rl has a port 36 to atmosphere, and the same may bc closed from within by the valve 23 by moving the latter to the position shown at P just below, in connection with the motor-pneumatic I. Preferably, in

.closing the passage 36, the valve 23 seats "upon an annulus 38, similar to the annulus 5, which may be of felt, chamois dr the iltl. I

Referring to Fig. 2-the annulus 38 may be secured to and backed by a support 39, oi. telt, pasteboard or other suitable material, which may in turn be supported by a plate 40, of metal if desired, which plate, at its periphery, may overlie the outer face et the movable bellows board 32 around the port 36, and may be secured to said'board, as by screws 41 shown in Fig. 4.

Preferably the annulus 38, support 39 and plate 40, or their substitutes, are substantially unitary in construction so that b removing the screws 41- (Fig. 4) all o the parts are permitted to be withdrawn from position to give ready access to the interior of the motor pneumatic. The aperture in the bellows` board 32 to receive the annulus 38 and theother parts connectedv thereto, may be large enough to permit withdrawal of the valve 23 when the annulus and other parts connected thereto have been removed as described. The bridge 28 or other means 'for supporting one end of the spring 27 may be formed integral with the plate 40 0r may be secured thereto in any practicable manner.

It is preferred that all of the movable parts,.as the stem 21 and valve 23, be of as light weight as practicable so that their inertia shall oii'er minimum resistance to prompt response in operation. For instance the stem 21 may be made of a light wood. The block 25 may alsobe made of light wood; or' else the block or its equivalent may be substantially integral with the valve 23, and the whole may be made of aluminum. It desired, the valve 23 may be made ofA cardfboard or aluminum andthe block 25 may be cemented thereto.

Referring to Fig. 3-the diaphragmcham- 105 ber 9. is there shown as communicating by a assage 45 with the duct 8 shown in Fig. l.

`o exhaust the chamber 9 when the same has V been closed to atmosphere a passage 46 leads therefrom to a bleeder vent 47, and the latter communicates with an upwardly inclined duct 48 (see the lower part of Fig. 3) which enters the exhaust chamber 16 at 49. The bleeding vent 47 may be provided conveniently by a constricted opening in the end 115 of a thimble of metal or the like, as shown in Fig. 3; and this thimble may be mounted in the passage 48, as by threading into it. Preferably the passage 46 and bleeder vent 47 communicates with' each other through an' 120 intervening chamber 50, which extends to the outer face of the board 13, andA is there provided with a transparentjclosure, suchv as a plate 51. of mica or glass. The plate 51 maybe readily secured in place by cement.' 125 When any stoppage occursinapparatus of this sort, itis most likely to result from an obstruction of the bleeder vent; and the arrangement just described permits ready inspecton of the bleeder vent 47 and also per- 180 Valve 23 downwardly an;

`and distende `.the `diapln" will remain inthe positie Communication. between tl' .nection with the motor pne'lnnatic H.

legarding the spring El?, it ellonld be said inits the saine to be when nec'essa-ry by merely stripping oil' the trans warent plate 51,` after which it'mav be readi;f cemented 'in place. Also the t iimble supplying. the

. The above described `Ineclianism operates, for the -purpees'of the specific illustration, s followed Atmosphere, mitted at the vent 7 inthe traekero, 'traverses the duct 8 i of chamber 9, thereby lifting the duplex primary valve 11.

This closes communication between the ein.-

hausty ehaniber 16 and the secondary diaphragm chamber 19; and also opens the ohambery 19 to atmosphere through the duct 2() and past the' disk of the primary valve 11. .Atmosphere thus admitted to the ohalnber 19s distende the diaphragm thereof and" V forcing thi-lf.

depresses the stem yQ1, the.

et thefforoevo `spring;Q7; and causing sagt. valve to seat on the annulue 3S to close the porte 36. Thus, at least'y n'xolnentarily, the parte take the positione shown atll"'in Fig. 1..

,y the `saine to Collapse, elevate ite` Sticker (l "and Sound its corresponding note. Thos the parts asln'ne'the positionee...own at Q, inb

open., the parts shown at Q, t, niterior. of the thonet 'chamber f the vent 7 'con.tin1.1.^-

motor pneun'iatio andthe 16 being maintained so that the corresu ond ing action is held in active noeition l hen, however, the `venit- T is olor atmosphere in exhausted from the dia Lgni chamber 9 through the bleeding vein. il?, and permits the valve 11 to assume the poeitionehown atR."v

lVhen the diaphragm of 'chamber 9 collapses (see R Fig- 1) and the valve 1l de scende, communication I.' ned between the Secondary diaphragm ci nnber "1.9 and the exhaust chamber itl, the @by balancing preesnreson opposite sides of the secondary dia fhra rn and .ermittino the valve to assume thepoeition"shown at This ,may

be asenistged'by `the spring contributing to thrust he 'valve upwarcllv against 1t; Seat Thi shuts ofi' exhaust from the interior of the nio'tor pnelnmttie and opens the sam to atn'iosphere through i thereupon pernflits the; parl positions Shown at the too f Fig. 1 in oonthat the same isnot .indiegafnieable. for this reason: When. the parts are in the position. rf-howrtat F10. 1 atmoe lierio Jreeenre Depression of Y "i the valve v23 opens' col'nnounita'tionfrom.y the .l-l'hauet chamber .1 6 through the passage 34' `correepondingly Shel i r' acte 'upon 4the lower fao ortho valve 23.

`This isY "opposed 'by atm A .ere actin upon the renter area oithe secondary dxap ragni of o'lambcr 19. Thee 'the Vdovitriwifl prese eure on said secondary diaphragm'prevails rand holds the valve 52S closed downwardly against upward resenre of atmosphere on, t

the Valve itself. hen, however, atmosphere isexhausted from the diaphragm chamber 19, the upward pressure of atmosphere on the valve Jrevail'e and the valve even Without the assistance of the spring 27, would be While wto tlieetegni Q1, andai'. al'i'othei'ti-me (l), Fig.

l) may beat an angle 'to the stemlQl. 'To aceon'nnodate these `dxllerent' v"angular 'rele'- tione 'of the etero `and rvalve, the end olf` the lstein may. be roinidecl `to coperato'with a l is on or con.,-` anee, .the recess neeted tothe valve; in the bloeit 25 may .lavo a with suoli an tug-rangen faire-.may be entirely free from any' improper restraint4 in its dilerent movements and inlay be al- Ways maintained inv pio er centered relation l. its .Seats and tlie'stei'n ill; Ae shown 1n 1 and t?, the ymotor pnetnnaties are arran ed in four tiem7 li, fl,

J and K. The indi'v'it ual `pnetnolatieef oi different tiere maybe in staggered relation permitting Atheir respective stickers to lie in the same plane alined across the Widthof the piano action. f'guide i" .il 60 having apertures to receive and goil the Stickers, may

" he mounted in anypraeticablesituation, as

upon `the stationary bellows boards 80 off the top tier of pneumatics. f

Aeilluetrated inl l, each sticker Gr of the top ticidiy i'n'nninted on its movable bellows board and to aceommodate the reslting oscillation of the sticker about the axis of movement oi the `bellows board,

insl

the guide rail (il) has :lor each snob. sticker an enlarge-.rl aperture (il. The coliitaeting parte of a sticker (i and Wippen l? preferably stand substantially in. the line of centers of their respective oseillatory movements; and therefore `their conjoint oecilh ion involves .minimum relative movement one on the other t t The lower tio" la, M and N are preferably e n, .y f the ,guirlng al'aorttn" o ot tho r. ,insure travel in iroper pa le; and to accomn'iodate such oscillation as may occhi' the' etiolters may i provide the main part of the chamberfl.l It has an aperture extending through it tof be connected to their respective bellows boards by opposed parti-spherical nuts 63, 64: having their convex faces adjacent. The upper end of each sticker may be capped by a felt pad 65.

The top board 14 and board 13 (Fig. 1) having between them the exhaust chamber 16, may extend from end to end entirely acrosseachtier; and the exhaust chamber 16 may likewise extend clear across the tier constituting a chamber common to all the pneumatics of the tier. It will be noted that the top board 14: is of very simple construction, it consisting merely of a flat board having recesses, therein to provide 'a secondary diaphragm chamber 194 for each pneumatic, a short duct 20,and a port extendin The bottom board of the exhaust chamber 16 is likewise of very `simple construction.l It is channeled nearly from end to end "to provide, in part, the port 34 for each pneumatic.V It is recessed to provide a primary c diaphragm chamber 9 for each pneumatic;

and each said chamber 9 has entering it a duct 4e and a4 duct 46. Likewise each cham-` ber 9 is accompanied by a chamber 50 and a passage 48 containing the bleeder vent thimble. The cabinet work to shape these boards in finished form is exceedingly sinnV ple comparedwith thatusually encountered in supplying parts for 'actions of a comparable character, suchas have been used heretofore; and this constitutes a very subn sta-ntial commercial advantage of economy.

The top'board 14 and the bottom board 13 of each tier may be assembled by simply screwing them together face to face; and they are preferably provided with some closure which will serve to make the joint-air tight. Such a closure may be supplied conveniently by a strip of paper or the like (Figs. 2 and 5) glued completely around the entire tier and forming a unitary and oliectively air-tightjoint.

To facilitate rupturing this joint to 'perf mit separation'of the boards 13- and 14, a groove 7 2 may be provided in the rear ofthe strip 70, permitting a knife edge or a pointed instrument to be inserted through the strip into the groove,-and then run along the groove to break the strip so far as desired. This is obviously more convenient than scraping or otherwise breaking the strip 70 when it is desired to part the same. The groove 72 may be supplied conveniently by rabbeting the upper edges of the board 13, or corresponding edges of the board 14 or both, if desired, or in any other practicable way.

A like construction of closure comprising a strip 70 'with or without a groove 72, may be employed in any practicable position for clear through the board for the primary va ve 11.4

closing joints in the pneumatic mechanism,y

7 8 by which the exhaust chamber 16 for the' upper tier communicates with the trunk 17. As shown the trunk 17 extends through a spacing block 80,' secured to the under side of the bottom board 13 and 'through a ma*- ingspacing block- 81 secured to th to board 14* of the second tier. The trunk 17 ikewise extends through the top and bottom boards of the second tier and through the exhaustchamber 16 thereof. The remaining tiers having the top boards 14b and 14, are traversed in like manner bythe trunk 17. Each of the spacing blocks, 81 may be lduplicated between other adjacent tiers; and they preferably extend clear across the tiers 'from front to rear, as indicated by `dotted lines at the left of Fig. 3.

Screws 67, 67 (Fig. 3) may ass through the successive boards and spacing blocks to secure together all the tiers. f l l I Fig. 5 showsl the arrangement'of spacing blocks and 'the like at one end only of the tiers of motor pneumatics and associated parts. As will be understood by those skilled in the art the spacing blocks may be duplicated at the opposite extremity of the tiers, either with or without a second trunk 17. In this manner the tiers may be -conuected at opposite ends in a unitary stack to be supported in any practicable manner in relation to the usual hammer actions ofa piano, or comparable actions of any other instrument. When supported `only at their extremities the tiers are likely to'sag' for want of support at intermediate points along their lengths; it is preferred therefore to supply strengthening means about'to be described.-

In the typical piano action, for instances-,-

,as is well understood bythose Vfamiliar with the artf-there arel certain breaks or spaces between the hammer act/ions` at or mediate the lengths of the tiers for properly spacing them apart and for supporting them cgllectively as a unitary structure. The strut 92v may be supported in any practicable manner at its lower endif desired. f

To contribute :further to the strength of the structure, each tier may have secured vintervals along the width of they action.

along its length a girder 95, preferably of metal; and the saine may overlie the closure strip. 7 0 and be secured in place by screwing to the board 1'3 ot each tier.- These girders 95 alone, whether in single lengths or sectional, tend to stiften each tier' and to support the same against sagging. Said girdcrs together with one or more struts 92 and the desci'ibed"'arrangement of the tiers, supply an exceedingly stable, unitan construction, which is at once compact anc convenient to insert and remove -from the piano action and very easyV to take apart and assemble.

It is to be understood that the. invention is by no means limited to the specific details of construction, organization and mode of operation hereinbefore described in connection with the speciticdisclosure of the drawings. 0n the contrary the invention issusceptible of-various embodiments such as will appear to those skilled in the art. It is by no means indispensable that all the features of the invention be used conjointly, since they may be used to advantage separately.

1. In a musical instrumenf-the'combination of' a pnl umatic; a, secondary valve within said pneumatic; a secondary cham bei' having a. d ohragm for controlling said valve; a-suppoitcoaxial with the valve to 'provide for relative angular movement 4olfsaid valve and support and to conti-ol said movement; and a primary valve mechanism t0 govern the pneumatic condition Within the secondary diaphragm chamber. l

2. In a musical instrument the combination cfa neumatic having ports in opposite boar s thereof; a valve controlling diaphragm; and valve means controlled by said 4diaphragm and including a stein and substantially unyieling avalve member y mounted thereon for universal 'relative anular movement to enable said valve -memf er always to maintain a. proper centered relation relative to said ports respectively and to its stem.

3. 1n a.4 musical instrument the combina- `tin of a'pneumatic; a diaphragm chamber having a diaphragm above the valve; valve controlling means depending from said dia-` phragm; a valve lor controlling said pneumatic and bearing against said controlling` V means; and means tohold the valve in posiboards thereof; a valve' adapted to seat against said ports respectively; a valve stem upon which said valve is mounted. for univers-al angular movement; a spring noi'- mally sustaining said valve; and a `valve conlrolling diaphragmto operate the valve -ii'i opposition to said spring.

5. 1n a musical instrumentthe coinbination of a pneumatic; a floating valve for controlling the condition therein; valve sustaining means, ineludinga spring, acting upon one face of said valve but disconnected therefrom; and pneumatic means act-ing upon the other face of the valve but disconnected therefrom.

6. In a pneumatic valve mechanism for musical instruments, the combination of a diaphragm chamber having a downwardly facing diaphragm; a depending valve conw trolling device secured to the diaphragm of said chamber; a valve separated 'from but acted upon by said device; and means to maintain said device and valve in operative relation.

7. In a pneumatic valve mechanism for musical instruments, the combination of a diaphragm` chamber having a downwardly facing diaphragm; a depending valve controlling device securedto said diaphragm; a valve separate. vfrom said device but governed. thereby;V land yielding means to maintain said device and valve in operative relation. A

8. ln a musical instrument havingbrealcs or intervals in the tone sounding action thereof, the combination 'of a. plurality of tiers of motor pneumatics; and supporting means for th 4tiers of said breaks or intervals. j Y i 9. In a m sical instrument having brcaks or intervals in its tone. sounding action, the comhipation of a, plurality Aof tiers of niotor pneumatics; and a strut to support said tiers at a break or interval.

10; In a musical instrument having a break` or interval 1n its tone sounding action, the combination of a plurality of tiersV It is hereby certified that in Letters Patent N o 1,253,744, granteddanuary 15,

1918, upon the application of Charles F. Stoddard, of Boston, Massachusetts, for

en improvement in "Musical Instruments, errors appear in tho print-od specification requiring correction as follows: Page 5, line 41, claim 2,*before the `word substam tielly insert the article a; same page, line 96, claim 8, for the word of read at; and that the said Letters Patent should be road with these corrections therein that the same may conform to the record of the onse in the Patent (Mice:

Signed and sealed this 26th day of February, A. D., 1915.

[SEAL] F. w. H. CLAY;

Acting Co'm'fstsfcioner of Przitents. Cl. Sli-118.

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