To all whom it may concern:
Be it known that I, LOUIS H. BROWNE, of Boston, in the county of Suffolk and State of Massachusetts, have invented certain new and useful Improvements in Pianofortes, and that the fdollowing description, taken in connection with the accompanying drawings, hereinafter referred to, forms a full and exact specification of the same, wherein I have set forth the nature and principles of my said improvements by which my invention may be distinguished from others of a similar class, together with such parts as I claim and desire to have secured to mee by Letters Patent.
My improvements are represented as applicable to what are called grand piano fortes, and are made upon, or in the sounding board iron frames, and action thereof, although they may be introduced, especially those which relate to the action, as hereinafter specified, into the square pianos.
In the drawings Figure 1 is a plan or top view of a grand piano forte, with the top cover entirely removed, and a single string only being shown therein. Fig. 2 is a longitudinal vertical section of the same, taken in the plane of the line A B, Fig. 1; the legs and pedals being dispensed with in this view. Fig. 3, is a detail plan of a subsidiary iron frame combined with the main iron frame, for strengthening the wooden frame of the instrument, and preventing it from crippling, and Fig. 4 is a plan of the under-side of the same , on one hald of the scale of the other figures, and Fig. 5 is a side elevation of my improved action.
a, a, a, a in Figs. 1, 2 and 4 represents the wooden framework of the instrument, braced for the purpose of resisting the strain of the strings, as shown in Figs. 2 and 4 or in any other desirable manner.
b, b, b is the sounding board of the shape shown in Fig. 1, and set on a wooden frame c, c, c around its edges, as shown by the dotted lines in Fig,. 1, and secured to the main framework a, a, a at the several points indicated, and by the screws d, d, d, passing through the edge frame c, c, c, as shown also by dotted lines in Fig. 1.
This sounding board, and its frame ccc it will be perceived by inspection of Fig., 2, do not touch any part of the framework, except the points of confinement before referred to at d, d, d, and therefore it is left free to vibrate or formed with a spring as it were, much more, than by the modes of construction and arrangement for the same, now in use. It is however necessary to sustain it, in order to make its vibrations perfect, at or about the center of the curved part thereof, and this I do by connecting it on its under side, to the outer end of the bent arm or lever f, f, Fig, 2 which is confined to the framework a, a, a, by the screw g, by which the said arm or lever may be confined in any desired position, and made to bear with greater or less force on said sounding board, so that said sounding board may be strained in a manner similar to that is which a drum head is strained, or so as to produce a similar effect.
h, h, h is the subsidiary iron frame, before referred to, constructed in the form shown in Fig. 3, and secured to the framework a, a, a just about where the hammers strike the strings, spaces or openings being left at i, i, i for the action of said hammers. The front rail of said frame is formed with an elongated rectangular socket, into which is fitted and firmly glued, a long wooden block k, fastened by screws to the underside of the front rail of the regular iron frame l, l, l, which extends all around the instrument.
By this arrangement or combination of two iron frames, great additional strength is secured to the whole instrument, and especially to that part thereof, where the hammers strike the strings.
I have made also an improvement in the upper iron frame, which consists in so casting the iron bridge m, m, on which the strings are strained, with or to the front rail of said frame, by means of the suspension brackets n, n, n, as that the said bridge is raised, so as to be above the level of the bottom of said frame, and the strings may be strained under the same, as shown in section in Fig. 2.
The action which I have devised in my improvements may be termed a reversed action, or one in which the hammer is nearer the front or ivory end of the key lever, than the center block of the same, by which arrangement the length of a grand piano, and the width of a square one my be considerably and economically diminished.
My improvements in this kind of action, consist in arranging a curved spring, in combination with the stem and center block of the hammer, and fly of the hack, so as to ease the escapement of the said fly, from the said center block, and prevent any snapping of the same, Also in arranging the "back catch" so called, on the end of a lever, having a fulcrum in said jack, so that it may act not only to catch the hammer , but also to operate the same, in repeating rapidly on one string of the instrument.
My said improvements are represented in Fig. 5, as before stated, in which o, o represents the key lever, to one part of which the jack p is confined, q is the fly of said jack, arranged with a spring r' in the usual way, so as to carry it under the notch in the center block s of the hammer, of which t, t is the stem, and u the head. The escapement of the fly of the jack is effected by means of the arm a', and regulating button b', operating in the usual manner,which will be readily understood by inspercion of Fig. 5. The spring for easing said escapement is shown at c', c' being coiled a little, where it is attached to the underside of the hammer stem. and then bent downward, and curved at its end, which bears against a groove formed in the front of the center block, and operated to effect its purpose, in a manner which will be understood by inspection of the drawing Fig. 5.
The back catch d' is secured in the front end of a lever e' h', which passes through the bottom of the jack, and has a fulcrum therein, as shown at f' Fig. 5. Its rear end projects out beyond the back of the jack, and under the rail g', and causes the back catch d' to follow the hammer, as it moves to strike the string i', the upper edge of said catch fitting under the ledge k', formed in the front of the hammer, as shown in Fig. 5, and if it is desired to repeat the stroke of the hammer, before the fly of the jack gets under the center block of the hammer for the purpose, a second stroke or touch on the key lever will carry the hammer up quickly again, by the action of this back catch on the hammer as set forth.
One other improvement which I have made in the action, consists in substituting a piece of gutta percha on the top of the hammer in lieu of some of the leather coverings thereof, as shown at l' in Fig. 5; one or two layers of leather being used above the gutta percha as shown at m'. By this improvement a more brilliant tone is secured than can be procured by the modes of covering the hammer heads as now practised.
Having thus described my improvements, I shall state my claims, as follows:
What I claim as my invention, and desire to secure to me by Letters Patent, is:
1. Arranging the sounding board in a springing form, and supporting its back on a straining lever, made to bear with more or less force against it, in the manner and for the purpose herein above specified.
2. I claim the combination of the short subsidiary iron frame, having a rectangular socket on its front rail, with the long main iron frame, having a wooden block on the under side of its front rail, which fits and is glued into the aforesaid socket, as herein before set forth.
3. I claim casting the bridge of the long iron frame, with curved brackets so as to have it raised above the level of the bottom of the front rail of said frame, and permit the strings to be strained, or strung under the same, as herein above explained.
4. I claim easing the escapement of the fly of the jack, from under the center block, of the hammer, by means of a spring, combined with said block ,and the stem of the hammer as herein above state.
5. I claim arranging the back catch on a lever, having a fulcrum in the hack, and arranged so as to cause the catch to follow the hammer, in a stroke of the same, and cause it to repeat the stroke or note if desired, when the fly of the jack fails to operate, so as to effect said second stroke.
6. I claim using a piece of gutta percha on the top of the hammer head, in lieu of some of the layers of leather, in the manner and for the purpose specified.
| LOUIS H. BROWNE. |
| Witnesses: EZRA LINCOLN, HENRY F. CONANT. |