USRE372E - Improvement in bellows for m usical i nstru m ents - Google Patents

Description

UNITED. STATES" PATENT OFFICE.

JEREMIAH CARHAR'I,'OF NEV YORK, N.

IMPROVEMENT IN BELLOWS FOR MUSICAL INSTRUMENTS.

Specification forming part of Letters Patent No. 4,912, dated December 2h, l-lf; Reissue No. 372, dated JuucZ-I, 1856.

To all whom z3 may concern:

Be it known that I, JnnnMniH CARI-mur, of the city of New York, in the county of New York and State of New York, have invented new and useful Improvements in that Class of Musical Instrum ents called Mel odeons, Scraphines, Eolian Attachments, &c.; and I do hereby declare that the following is a full, clear, and exact description of the principle or character which distinguishes them from all other things before known, and of the manner of making, constructing, and using the same, reference being had to. the accompanyingdrawings, making a part of this specification, in which- Figure lis an end elevation; Fig. 2, an inverted bottom view; Fig. 3, a vertical section taken at the line X X of Fig. 2, and Fig. 4 a horizontal section taken at the line Z Z of Fig. l.

The same letters indicate like parts in all the figures.

Instruments of the kind above mentioned l1 ve prior to my invention had their reedboards combined with double-chambered bellows whose parts were so constructed and arranged that the air was condensed within them by the action of the bellows, so as to cause the reeds to vibrate when the reed-valves were opened by the rushing of said condensed air out past and through the reeds into the atmosphere. On examination and experiment I found this Inode of construction subject to many serious objections.

First.v Unless the top of the instrument-the key-board-is permitted to be constantly vibrating as the bellows operates i't-requires a Wind-chest, which makes it more cumbrous and expensive, and which must be capable of being opened, like the top of a piano-forte, and yet must be and remain,when closed, substantially air-tight. The latter quality it has constantly a tendency to lose more and more with time, in consequence of the outward pressure of the condensed air within.

Secondly. Under this construction all the joints of the entire instrument have a tendy ency to open and get out ofrepair, in conse current of air, the reeds, with the open plates to which they are attached, must be placed within the instrument, under the reed-board, so thatin constructingthe'instrumen t, if found to operate imperfectly, they cannot be examined or taken out without opening the instrument, and as this stops the operation of the reeds they cannot bc inspected while in place and in operation to detect the cause of their imperfect action preparatory to correction. The same difficulties also present themselves when repairs become necessary, and render the task one of great diiculty and perplexity.

Fourthly. The reed-valves,which are raised by the keys in playing to admit the air successively to the reeds, are under this construction pressed by the condensed air against the openings in which the reeds are placed with the full force of the condensation of the air within, thus rendering the ngering hard and difficult.

Fifthly. As the vibration of the reeds under the old construction is produced by currents from a small wind-chest, in which the air is kept in irregular agitation by constantly changing the point of discharge, and against the full pressure of the atmosphere, it is found that the reeds will not alwaysy speak or give forth their sounds sufiiciently quick, and it is also found that the tone,when given out, is inferior.

The foregoing aresome ofthe defects ofthe old construction of reed-instruments, and my improvements are made principally for the purpose of obviating them.

My invention consists, principally, in soconstructing, combining, and arranging the parts of said reed-instruments that the reeds shall be vibrated in playing by the rushing of the external 'air inward to a partially-exhausted chamber, instead of forcing it outward, as previously practiced; and this I accomplish by placing the reeds on the outer or upper side of the reed board, placing a chamber capableof expansion and contraction in communication with the under side of the reeds, said chamber having an aperture closed bya valve which opens outward intov a second expanding and contracting chamber or air-pump, which also has an aperture closed by a valve opening outward. One of the iiaps of the last-mentioned chamber is connected with a treadle, by which l ponderates over the weight on the irst ilap it is operated to expand and contract the chamber, by which means the first chamber is exhausted of itsair by the pump. The latter operation may be aided by weights or springs, it' desired; and the iirst chamber should be Y provided with a weight or some other equivalent operating constantly to distend it. l iind six or eight poun-ds to the square foot of the lllap to be preferable. By these improvements it is readily perceived that the wind-chamber or wind-chest is entirely dispensed. with. As the air within is exhausted, the pressure of the air from without tends to tighten the seams of the instrument, rendering it more durable, and .keeping it in repair and preventing leakage.V The reeds are on the ontside, so that any defect can be observed while the instrument is in operation, and can be removed for repair without opening the instrument. The reed-valves can be opened by the slightest touch ol the keys. The reeds, having a supply of air direct 'from the atmosphere, will speak immediately, and the tone will be much improved, as will be observed on eX periment, thus at once obviating the leading defects of the old construction.

ll have also made an improvement in the valves of reed musical instruments.

lln the accompanying' drawings, a represents the sound board or table, to which the reeds b b are secured in any desired or well-known manner, with the reeds above, so that the tone shall be produced by currents passing toward the bellows. The reeds are placed over apertures .in the soundboard, in the usual manner, leading to the first chamber, c, formed bythe sound board, and the first fiap, d, which is jointed in any desired manner to the back of the soundboard, and connected to the ends and the front by means usually employed in connecting the liaps of bellows. The forward edge of this iirst ilap has a weight, e, attached to it, which tends constantly to draw it down by an equal force to give an equal current of air, and therefore to produce a regular vibration of the reeds. This first iiap is provided with two series of apertures, ff, covered by valves on the under side, made in manner to be hereinafter described. To the weighted edge of this first flap is jointed the second flap, g, the two being connected at the ends and backfto form the second chamber, h, in the same manner as the lirst is connected with` the sound -board; and these two iaps are drawn together by a spring, il, on'e leaf of which is secured to each of them, so that whenever the foot is removed from a treadle, 7c, connected with the second iiap by a strap, l, this spring draws it right up against the first flap, by which action all the air previously contained in the second chamber is forced out through a valve, m,- and when this iap is drawn down by the pressure of the foot on the treadlc the air contained in the irst chamber is exhausted therefrom; and as this process of exhaustion goes on the pressure of the atmosphere pre and forces it up, so that when the second flap is relieved of the pressure of the foot the spring immediately begins to draw it up. This relieves the iirst lap of the pressure ot' the atmosphere, which acts on it by the intervention of the second iap jointed to it, whereupon the weight begins to descend to keep up the constant and steady action of the air on the reeds.

The manner in which the pressure ol' the atmosphere acts to force up the iirst iiap when the first chamber is partly exhausted, will be evident when it is observed that the second flap is drawn down by one edge, the other being jointed to the front edge of the first flap, so that the pressure of the atmosphere on the under side of the second flap tends to force up the two flaps, notwithstanding the back of the lower one is carried down by the treadle, thel connection `oil" the treadle acting merely as a movable fulcrum for the upward movement of the front of the two laps when forced up by the pressure of the atmosphere. The valves of the two laps are formed by a strip of thin leather or other like material secured at each end over a hole or series of holes, a, (shown by dotted lines in lFig. 2,) and then overy this leather is stretched a strip or corcho, of india rubber or other similarly elastic substance, which permits the leather to open sufiiciently for the passage of the air, but which at the same time prevents the leather from sagging down so far as to -liap and make a noise when suddenly closed by the pressure of the air, as would be the case after being in use for a short time without the spring. The upper or first chamber is provided with an escape hingevalve, p, opening inward, and kept closed by a spring, r, but which is opened by the upper or first flap striking the lever s of the\valve when the operator Works the lower or second flap faster than is necessary. The treadle 7.1, which cannot be attached to the floor conveniently, is cutout, as at t, as represented by dotted lines in Figs. 1 and 3, As ufiiciently to permit the heel of the operators foot to pass through and rest on the floor, to prevent the treadle from being pushed forward when the forward part of the foot acts on the part u to bear it down.

It will be obvious that other kinds of valves may be substituted for those described without changing the leading part of my invention, and that any other appropriate spring' may be employed to draw together the two iiaps, and, finally, that any desired mode ol connecting the various parts may be employed,

so long as the character of my invention or.

any part of it is retained.

It is obvious that many changes in form and in the mere arrangement of parts may be made without departing in the least from the principle of my invention, so long as the er haast-chamber communicates with the reeds, nd the second chamber or pump exhausts the rst.

BEST AVAILABLE CCPY Having thus fully explained the nature of my improvements in reed musical instru ments, and pointed out several modin which I have contemplated the application thereof practically, what I claim as new therein and my own invent-ion, and desire to secure by Letters Patent, is-

The combination of the reeds with an exhaust-chamber of variable capacity, and an air-pump whose action exhausts and rarefies the air therein, the exhaust-chn1nber tending to expand with a force that will balance the rarei'action to be preserved in the chamber, for the purposes herein set forth.

.T. CARHART.

\\'itnesses:

SAM. C. SWARTY.. WM. DIXEY, JoHs J. MURRAY.

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