US1250428A - Pneumatic player-action. - Google Patents

Description

F- CARNAHAN.

PNEUMATIC PLAYER ACTION.

APPLICATION FILED 050.11, 1916.

1,250,428 Patented Dec. 18,1917.

2 SHEETS-SHEET I.

INVE/l 70/? F. ()ARNAHAN.

PNEUMATIC PLAYER ACTION.

APPLICATION FILD DEC-H, 1916.

Patented Dec. 18, 1917.

2 SHEETSw-SHEET 2.

FRANK CARN'AI-IAN, OF SOUTI-IdBOSTON, MASSACHUSETTS, ASSIGNOR T0 EMERSON PIANO COMPANY, OF BOSTON, MA SACHUSETTS, A CORPOIQACKON ZLLINOIEL PNEUMATIC PLAYER-ACTION.

Specification of Letters Patent.-

Patented Dec. ltd, 3191?.

Application filed December 11, 1916. Serial No. 136,217.

To aZZ whom it may concern.

Be it known that I, FReNK CARNnHAN, a citizen of the United States, residing at South Boston, in the county of Suffolk and State of Massachusetts, have invented certain new and useful Improvements in Pneumatic Player-Actions; and I do hereby declare the following to be a full, clear, and exact description of the invention, such as will enable others skilled in the artto which it' appcrtains to make and use the same.

My invention consists in the novel features hereinafter described, reference being had to the accompanying drawings which show one embodiment of the invention selected by me for purposes of illustration, and the said invention is fully disclosed in I the following description and claims.

Referring to the drawings:

Figure l is a vertical sectional view or a portion of a piano with one embodiment of my improved player action arranged therein.

Fig. 2 is an enlarged vertical transverse sectional view through the action banks or decks showing my invention embodied therein.

Fig. 3 is an enlarged top plan view of the guiding portion of one of the "alve stems, the guiding aperture being indicated in dotted lines.

Fig. i is a detail view of the valves and stem for a single pneumatic, removed.

Fig. 5 is a top plan view ot a portion of the upper bank or deck illustrated in Fig. 2.

Fig. (3 is a front elevation of a portion of said banks or decks showing two pneumatic actions in each bank or deck, one of the detachable vent blocks and one of the detachable valvc caps being removed.

Fig. 7 is a detail view ofone of the vent blocks detached.

S is a detail view of one of the valve caps detached.

9 is a detail view of a tool which may be used to remove the valve caps.

My invention relates to player actions'for operating the hammers of a musical instrument, for example, a piano. Such actions comprise a plurality of striker pneumatics each of which is operatively connected With.-

- on of the hammers of the instrument, the

said pneumatics being selectively placed in communication witha common air exhausting (or air pressure) device by the operation of suitable valves controlled by valve operating diaphragms connected .With .a tracker board. provided with a separate aperture communicating with each of the, diaphragms and selectively operated by means of a traveling note sheet provided with apertures registering with those in the tracker hoard.

/In the manufacture of player actions of this character the striker pneumatics and their associated valve mechanism for the several hammers do not act with absolute uniformity, some requiring greater power than others to operate them with the same degree of force so as to produce as nearly as possible the same touch in. actuating the hammers. This lack of uniformity of operation may be due to many causes, such as slightvariations in the resilience of the flexible material of the bellows, slight differei'ices of seepage orleakage of an almost infinitesimal character at the joints of the various parts, slight variations in the adjustment of the respective valves and valve actuating mechanisms, etc, and these com paratively slight variations may occur in the original construction of the instrument, orsome of them may develop in the instrument owing to climatic condition or atmospheric conditions, after the i/iistruments have been placed on the market or filiave gone into use. I i l These slight variations will occur from some,-or many of the causes mentioned, and other causes, no matter how ca refully'the apparatus is constructed in its manufacture, and while. they do not necessarily produce noticeable differences in the operation of the hammers when a heavy volume of air is employed to produce loud tones, these s ight variations become more noticeable in the piano and pianissimo effects, and if the suction (or pressure) is reduced beyond a cer o I l tam limit, certain of the pneumatics, to wit,

those requiring greater power than otf aers, would cease their operation before othe s of the series, making it necessary to maintain, at all times a minimum suction or pressure sufficient to insure the actuation of the most reluctant striker neumatics, Therefore, in the playing of the instrument, when the most reluctant pneumatics are operating their hammers to produce their softest tones, the more readily operable pneumatics would be producing perceptihly stronger blows, and in playing for example, chords and arpegg'ios softly, the notes would sound unequally,

and if the suction or pressure) fell below that required for the most reluctant pneu- Inatics, certain notes of the chords or arpeggios would not be sounded at all. in practicethis precludes the possibility of obtaining the softest and most delicate playing of the instrument.

One of the objects of my invention is to provide the controlling mechanism for each individual striker pneumatic with means readily accessible from the front of the instrument, without removing the player action, whereby the individual controlling Valves for the pneumatic can be removed, adjusted and replaced in proper relation with their respective 'alve seats and with .l their actuating diaphragm, and also to pro- 'v 1de means whereby the bleed or vent aperture may be readily exposed for the purpgseof cleaning it or for the purpose OI varying the' size of the minute aperture thereof, to the end, that each individual pneumatic may be adjusted so as to operate accurately under the same and a very low suction or pressure, so that all the hammers can be operated'at the lowest suction or pressure required to operate any of them, and

enabling delicate passages to be played more softly than is possible with ordinary player actions, WlillE at the same time insuring the correct operationof every pneumatic.

My invention also permits of another ad vantageo'us result. It frequently happens that after an instrument has'been in use, one or more striker pneumatics fail to operate With the desired uniformity and sometimes refuse to operate at all owing to the valve sticking, the bleed becoming stopped or to other causes, and in many instances, it is necessary to ship the instrument to the factory or repair shop, or remove the player action therefrom, and return it to the factory or shop for correction. By my invention the access to the controlling valve mechanism and bleeds is rendered so simple that without removing the action from the instrument f and means for supporting the roll contain ing theperforated note'sheet, the position of Which is indicated by dotted lines at a. 5

represents the tracker board of any usual or preferred construction and 6 represents the connected in any usual ordinary piano keys with the hammers or or desired manner striking mechanism of the instrument.

Each of the banks of actions is of similar construction and a description of one will apply equally to all. 10 represents the air trunk, which extends, in this instance, continuously from one end of the bank to the other, across the piano, and is connected in any usual or preferred manner with the air exhausting mechanism (or compression mechanism) which may be operated .by treadles or by motor, as preferred. air trunk in two pieces, to wit,'a bottom portion or diaphragm board, 11, and a top portion, or valve board, 12, the air trunk, 10, being formed by recessing the diaphragm board as shown throughout its entire length. In the bottom of'the recess forming the trunk or chamber, 10, i provide a series of sub-recesses, 13, each of which is covered by a diaphragm, 14, provided on its outer face with a pad, 15. I provide the diaphragm board, 11, with a channel, 17, extending from the recess, 13, to the front face of the diaphragm. board, and a vent passage, 18, extending from the air trunk recess, 10, to the front face of the diaphragm board. Each of the vent passages, 18, is provided with a removable device preferably in the form of a cup-shaped nipple, 19, having a bleed aperture. 20, therein, the said nipple being reniovably secured in the outer end of the passage.

'lhese nipples are provided in quantity, with bleed apertures of different sizes so that the bleed aperture can be quickly adjusted by simply removing one nipple and replacing it by another, having a larger or smaller bleed aperture, as desired. In order to give access to each individual vent passage, 18, for the purpose of changing or cleaning the nipples, when desired, I provide a. plurality of removable vent blocks, 21, each one of which is provided with a recessed portion, 22, adapted to place the vent passage. 18, in eommuni aiion with the passage, 17, leading to its diaphragm chamber, 153. This may be accomplished as shown, by simplyboring a circular recess in the vent block, 21, as indicated in Fig. '7, having a diameter suflicient to connect the two passages, 17 and 18. The front face of the diaphragm board, 11, is provided with a packmg ring, 23, to be engaged by each vent block and the vent blocks, 21, are held in position by screws, 24.

I prefer to provide each vent block with scarfs, 25, substantially equal in width to one half of the body of one of the retaining screws, 24, so that the lower portion of the blockis substantially equal in width to the distance between two adjacent screws, 24. By simply loosening the screws, 24, at each side of the vent block, 21, the vent block I prefer to form the can be readily raised from between its retaining screws and removed, and also may be readily replaced and secured in position by simply tightening the screws, which need never be removed. It will also be seen that by this construction the scarfs, 25, at adjacent ends of two vent blocks form a recess of the width of the body of a screw, 24, and the head of each screw will engage and retain two adjacent vent blocks. Each of said vent blocks, 21, is provided with means .for connecting it with one of the apertures of the tracker board, 5. In this instance I provide each vent block with a short tubular section, 26, leading into the recess, 22, and connected by a tube or other suitable connection, 27, with one of the aperturesdn the tracker board in a well known way.

The valve board, 12, of each action bank isprovided with valve chambers, 30, circular in cross section, each of said chambers being located above and concentrically with respect to a corresponding diaphragm reccss,'13, in the diaphragm board, and-each of said chambers, 30, having a concentric aperture, 31, inthe bottom communicating with the air trunk, 10. The bottom of the chamber, 30, surrounding the aperture, 31, constitutes a valve seat which is normally engaged by a disk valve, 32, adjustably secured to a valve stem, 33, the lower end of which is suspended over the pad, 15, on the diaphragm, 14, extending across the corresponding diaphragm recess, 13.

Each valve chamber, 30, communicates by a -passage,'34, in the valve board, 12, and a passage, 35, in the diaphragm board, 11, with an aperture, 43, in the top member, 44, or" an action pneumatic, 40, the movable member, 41, of which is provided with an arm or finger, 42, or other suitable means for connecting it operatively with one of the striker actions of the piano in any usual or desired manner so that the collapse of the pneumatic, 40, will cause one of the hammers to strike a string and sound a note. The valve stem, 33, is threaded adjacent to its upper end and the valve, 32, is screwed thereon so that it can be adjusted by simply turning the valve with respect to its stem, thus adjusting the length of the depending ortion of the valve stem, with respect to its actuating diaphragm. I provide the valve stem, 33, with a second valve, 36, adapted to engage a valveseat on the underside of a-removable valve cap, 38, and surrounding an aperture, 37, therein. This valve any: is removably attached to the valve boardJz; afndcovers the valve chainber,30, therein, being understood that there is one of these valve caps for each of the valve chambers, 30. rat valve, 36, is held flexibly on the valve stem, 33, and can also be adjusted independently of the valve, 32, by means of an'ut, 33*, on the stem.

For the purpose of guiding the valves in their movement I provide the valve stem below the valve, 32, with a guide block, 32 having portions in loose guiding engagement with the walls of the aperture, 31, in the bottom of the valve chamber, 30, the block being fiutcd to allow a free flow of air through the aperture, 31, when the 'valve, 32, is raised. When the valve stem is in its lowest position the lower valve, 32, will always seat accurately as the lower end of the valve stem is normally held out otcontact with the diaphragm, and when the stem is raised by the diaphragm, the valve, 36, will seat accurately by reason of its flexible con= nection with the stem. Slight variations in the position of the valve stem therefore do not affect the accurate seating of the valves.

Each of the valve caps is held in position air-tight upon the valve board, 12, by means which enables it to be instantly and readily removed by an operator from the front of 'the piano without removing any of the banks of the action from the casing. In the present instance, I have shown the rear end of the valve cap, 38, provided with scarfs, 39, at the corner portions thereof to engage retaining screws, 45, and the forwardly extending end of each of said valve 'caps is held in position by a laterally movable device, in this instance, a screw hook, 46. The valve cap, 38, is provided With a beveled face, shown at 47, Figs. 2 and 8, to

facilitate the removal of the rear edge from underneath the heads of the screws, 45, without unscrewing these screws which never need be disturbed in removing and replacing the valve cap.

The valve board, 12, is provided with a packing, 48, surrounding the valve chamber, 30, and in assembling the parts the screw hook, 46, and the retaining screws, 45, will be drawn down so as to clamp the valve caps firmly in position upon. said packing making an air tight connection. It will be seen that if it is desired to obtain'access to any one of the valves, 32 and 36 at any point along either bank, it is only necessary to turn the screw hook, 46, andraise the front end of the valve cap38, which rocks upon the angular portion, 50, at the intersection of the bevel, 47, with the bottom 1 ace of the cap, thereby lowering the rear edge of the cap .from'beneath the heads of the screws, 45,

fulcrum, forcing the rear corner portions into firm. engagement with the heads of the screws and depressing the front end until it can be secured in position by turning the screw hook, 4c. The screw hook, 46, may

beturned to disengage or engage the cap,

the tubular member, 26, temporarily although this is not essential. I am aware of the fact that in some pneumatic actions a cap plate is employed which is secured in position by means of glue, or by screws, or both. These caps are secured in place in the factory and cannot be removed without removing the action from the instrument. In other words the screws or glue merely serve to hold the parts permanently in assembled relation, and are not intended to render the cap plates readily detachable while the action is in operative position in the instru ment. If the parts are removed from the instrument and detached by taking out the screws or loosening the glue, they would have to be reassembled as in the first instance and the parts made tight with the same care (and usually by use of glue or shellac) as in the first assembling of the parts. Such cap plates held in place by gluing or screws are not truly detachable inthe sense in which my improved cap pieces, 38, are detachable,- and to distinguish from such constructions I have defined the means by which my improved cap pieces are held in position, as capable of being instantly disengaged, while the action is in operative position in the instrument.

From the foregoing description it will be apparent that in a piano player embodying my invention the operator by removing the fall board or front board may obtain access to the valves, 32 and 36, and also to the bleed, of every individual player pneumatic without disturbing any other part'of the apparatus, and without removing the action from the piano. For example, when the machine is in the factory after being assembled, it maybe given a final adjustment during which the player may be operated under the lightest possible air pressure to ascertain which of the actions are most reluctant and these actions can be made uniform with the others by specially adjusting the valves, 32 and 36, or the bleed, therefor, in the manner previously described. It will also be seen that after the instrument has been placed on sale or installed in a home for use, if at any time one or more of the player pneumatics appears not to be operating in the desired manner, an ordinary piano tuner or other;

operator familiar with the construction of the action embodying my invention, can

readily adjust the valves or breed for any 1 have found in actual practice that by.

my invention 1 am enabled to adjust the individual valves, and'36, and the bleed aperture 20 of the individual player pneumatics so as to obtain absolute uniformity in the operation of all the hammers acted upon by the entire series of pneumatics so that they will respond equally under all air tenslons, even the lowest air tension that will operate any of the pneumatics, and I have thereby obtained greater delicacy of touch than is possible with the construction in which the individual valve mechanism of the action pneumatics cannot be independently adjusted as in my construction.

I am aware of the fact that player actions have been constructed in which each individual pneumatic and its controlling parts of the unit itself can be separated or adjusted without removing it from the instrument, and the unit system is subject to the serious objectionthat it is difficult if not practically impossible to make air tight the necessarily large openings forming the communications. between the individual units and the main air trunk. I am also aware of the fact that adjustable valves have been proposed, but they were used in constructions in which it. was not possible to remove and adjust the individual valves and replace them without removing the action from the piano case, and as a matter of fact, such adjustments were what may be termed factory adjustments to be made be fore or at the time of assembling the parts of the apparatus. i

By my impi oved construction herein disclosed I provide for a far greater control of the individual player pneumatics than is possible even in the unit system, while avoiding the objectionable features of the mounted hook member adjacent to an opposite edge of the cap adapted to be instantly engaged with and disengaged from the cap while the action is inoperative position in the instrument.

6. In a pneumatic action for musical instruments, the combination with a pneumatic, exhausting means therefor, a valve chamber connected with said pneumatic, and having an opening at the top large enough to permit the removal of the valves, a cap for said opening provided with a port, and a valve seat surrounding said port, said valve chamber being provided with a port communicating with said exhausting means,

and a valve seat surrounding the same,

valves located in said chamber for engaging said seat, a valve stem adjustably connected with said valves, said stem and valves being capable of lateral play to facilitate the seating-of the valves, means for loosely guiding said valves and stem, without preventing the lateral movement thereof} and securing means for said cap capable for being instantly disengaged while the action is in operative position in the instrument.

7. In a pneumatic action for musical 1nstruments, the combination with a pneumatic, exhausting means therefor, a valve chamber connected with said pneumatic, and

having an opening at the top large enough to permit the removal of the valves, a cap for said opening provided with a port, and

a valve seat surrounding said port, said valve chamber being provided with a port communicating with said exhaustingmeans, and a valve seat surrounding the same, a valve stem extending vertically and loosely throughsaid chamber, valves within the,

chamber adjnstably secured to the stem, a guide adjustable on said stem and loosely engaging said last mentioned port for guiding the valves and stem while permitting lateral movement thereof, a pneumatic for actuating said valve stem, and securing devices for said cap capable of being instantly disengagedwhile the action is in operative position in the instrument to facilitate the adjustment of the stem with respect to the valves and said actuating pneumatic.

8. In a pneumatic action for musical instrnmcnts, the combination with a pneumatic, cxlnuisting means therefor, a valve chaniberconnectcd with said pneumatic, and having an opening at the top large enough to permit the removal of the valves, a cap for said opening provided with a port, and a valve seat surrounding said port, said valve chamber being provided with a port comniunicating with said exhausting means, and a valve seat surrounding the same, a valve stem extending vertically and loosely through said chamber, valves in said cham her, one of said valves being adjustably con- :ing any other part of the action unit or an other action unit.

nected to the stem, and the other valve being loosely mounted on the stem, a nut adustable on said stem engaging sald loosely mounted valve, means for loosely guiding gaged while the action is in operative position in the instrument to facilitate the adjustment of the valve stem with respect to said actuating pneumatic and of the valves with respect to said stem. a

9. In a pneumatic action for musical instruments, the combination with a plurality of power pneumatics, a common air trunk therefor, a valvev chamber for each pneu matic connected therewith and with the air trunk, and with the atmosphere, valves in said chamber for controlling said connections, a valve actuating pneumatic for each valve chamber provided with an air inlet passage, a removable vent block for each valve actuating pneumatic, provided with a recess communicating with the valve actuating pneumatic and with the tracker board, a bleed passage communicating with the recess in each ofsaid blocks, a removable bleed device provided with a reduced opening in said bleed passage, whereby any one of said blocks may be removed for the purpose of cleaning the single bleed associated therewith, or of removing the bleed device and replacing it with another having a different size bleed aperture, without disturb- 10. In a pneumatic action for musical instruments. the combination with a plurality of power pneumatics, a common air trunk therefor, a valve chamber for each pneumatic connected therewith and with the air trunk, and with the atmosphere, valves in said chamber for controlling said connections, a valve actuating pneumatic for each valve chamber provided with an air inlet passage, a removable vent block for each valve actuating pneumatic, provided with a recess communicating with the valve actuating pneumatic and with the tracker board, a bleed passage communicating with the recess in each of said blocks, a removable bleed device provided with a reduced opening in said bleed passage, retaining screws having enlarged heads, located at each side of each vent block, each vent block being provided with cut away portions at each side, to enable it to pass between said screws and forming shoulders to rest upon said screws and support the block, whereby anyone of said blocks may be, removed by loosening said screws without removing them.

of power pneumatics, a common air trunk ed Without removing the pneuinatics and connected parts.

What I claim and Letters Patent is:

1. In a pneumatic action for musical in struments, the combination with. a pneumatic, and exhausting means therefor, of a valve chamber connected with said pneumatic, and provided at one end With an aperture in communication with the atmosphere, large enough to permit the removal of the valves, a removable cap for said aperture provided with a port and a valve seat surrounding the same, and forming the only means for retaining the valves in said chamber, said chamber being also provided with a port communicating with said exhausting means, and a valve seat surrounding the same, valves said chamber for engaging said seats, means connected With said valves for adjusting them, means for actuating said valves, and securing means for said cap adapted to be instantlydisengaged While the action is in' operative position in the instrument to permit the removal, adjustment and replacement of the valves Without disturbing the other parts or" the action or other actions;

n a pneumatic action for musical instruments, the combination with a pnett 'matic, and exhausting means therefor, of a surrounding the same, and forming the only means for retaining the valves in said chamber,

means, and a valve seat surrounding the same, valves in said chamber for engaging said seats, means connected with said valves for adjusting them, permanent securing means for engaging a portion of saidcap at one side or" the same, and securing means adapted to be instantly disengaged While the action is in operative position in the instrument, located adjacent to an opposite edge of the cap, to permit the removal, adjustment and replacement. of the valve Without disturbing the other parts of the action or other actions.

3, In a pneumatic action for musical instruments, the combination with pneu matic, and exhausting means therefor, of a valve chamber connected with said pneumatic and provided at one end with an aperture in communication with the. atmosshare large enough to permit the removal oft desire to secure by said chamber being also provided'vvith a port communicating with said exhausting the valves, a removable cap for said aperture provided with a port, and a valve seat surrounding the same, and forming the only means for retaining the valves in said chamher, said chamber being, also provided With a port communicating with said exhausting means, and a valve seat surrounding the same, valves in said chamber for engaging said seats, means connected with said valves for adjusting them, permanent securing means for engaging said cap adjacent to one edge of the same, said cap having beveled portions adjacent to said permanent securing means to facilitate. the disengagement of the cap therefrom, and securing means adapted to be instantly disengaged While the action is in operative position in the instrument, for engaging the cap adjacent to an opposite edge from said permanent securing means.

l. In a pneumatic action for musical instruments, the combination with a pneumatic, and exhausting means therefor, of a valve chamber connected with said pneumatic and provided at one end 'With an aperture in communication With the atmosphere large enough to permit the removal of the valves, a removable cap for said aperture provided. With a port, and a valve seat surrounding the same, and forming the only means for retaining the valves in said chamher, said chamber being also provided With a port communicating with said exhausting means, and a valve seat surrounding the same, valves in said chamber for engaging said seats, means connected with said valves for adjusting them, and securing means for said cap including a pivotally mounted member adapted to be swung over a portion of said. cap, and to be instantly disengaged therefrom While the action :is in operative position in the instrument,

5. In a pneumatic action for musical instruments, the combination with a pneumatic, and exhausting means therefor, of

a valve chamber connected With said pneu; matic and provided at one end With an aperture in communication With the atmosphere, large enough to permit the removal of the valves, a removable cap for said aperture provided with a port, and a valve seat surrounding the 'same, and forming the only means for retaining the valves in said chamher, said chamber being also provided With a port-communicating with said exhausting means, and a valve seat surrounding the same, valves in said chamber for engaging said seats, means connected W'ithsaid valves for adjusting them, permanent securing means for engagingsaid cap adjacent to one edge, said cap having a beveled portion adjacent to said permanent securing means to permit the cap to rock and facilitate the engagement and disengagement of said per manent securing means, and. a pivotally therefozg. a valve chamber for eiwh pneu- "dad with a matic conneckd therex'vith and with the air "1. H L cenmc'vion attending trunk and W551 the mimosphere, val es in said chamber or 00 elling said connecmeans; tlons, a valve actuating pneumatic for e: ch the nctian is in epe'rzmvep valvr; chamber provided with an air inlet strumel'lt for holding each passage, a removable vent block for each blocks independmt iy in 0 .119

211W actuating pneumatic prox'idec i Wiiil 1 fhareby any-02m 0'? said 'zl" recess connnuniczzflg with said k air inlet 219d and ep-laced Withuu passage, said air trunk being provfided with part oi 116 nctikm unit cmmcfl's:

a bleed passage communicating with i; m re- T I or any @ther (.(Ji'iOl'i'Ullii).

cess of each Tent Mo k, and pmvimd Wifh tess'hinony he 1 i" a reduced bleed uperi (2, each of efl z ARK

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