US288279A - Stringing pianos - Google Patents

Description

(No Model) L. G.-TH.ERRIEN.

STRING-1N6: PIANOS.

No. 288,279. Patented Nov. 13, 1883. 5: 1 H 7 n FL- 5' I I! l 1 W b1 2 5 s as.

" UNITED STATES PATENT OFFICE.

LOUIS O. TIIEERIEN, OF MONTREAL, QUEBEC, CANADA, ASSIGNOR, BY DI- uEOT AND MESNE ASSIGNMENTS, OF SEVENTEEN TlVENTY-FOURTHS TO AUGUSTIN LAVALLEE AND ADOLPHE OUIMET, OF SAME PLACE, AND TREFFLE GAROEAU, OF BOSTON, MASSACHUSETTS.

STRINGING PIANOS.

SPECIFICATIQN forming part of Letters Patent No. 288,279, dated November 13, 1883,

Application filed May 18,1883.

To all whom it may concern.-

Be it known that 1, Louis 0. THERRIEN, of Montreal, in the Province of Quebec and the Dominion of Canada, have invented a new and useful Device for Stringing Pianos, of which the following is a specification.

My invention relates to improvements in devices for stringing pianos, in which levers are employed for maintaining the desired strain.

Hcretofore in stringing pianos by means of levers the lon arm of the lever has been secured by means of a spring. In such arrangement it is evident that the tension of the spring, and consequently the strain on the string, must I 5 vary, since the slight movement of the short arm of the lever, caused by the expansion and contraction of the string, causes a great movement of the long arm, thereby bringing a greater or less strain on the spring.

The object of any invention is to provide a device for keeping the strings of apiano-forte under a constant and unvarying tension, so that when a string is once adjusted to the proper tension-say to produce a certain musical 2 5 note-it will continue to give that note and no other with out further adjustment or tuning, (as it is commonly called,) regardless of the use, abuse, or changes of temperature to which it may be subjected.

My invention is obviously applicable to any line or cord subjected to strain.

My invention consists, mainly, in the combination,with a string secured at one end, of a weight connected to the string by a system of 3 5 levers proportioned to cause the weight to produce the desired tension, as hereinafter fullyset forth.

In the accompanying drawings,whieh illustrate so much of a piano string frame and 40 sounding-board as is deemed necessary to show my improved device for straining the strings as arranged in the best way now known to me,

Figure l. is a longitudinal section, showing a string of an upright piano with the straining 5 device attached. Fig. 2 is a front view, and

Fig. 3 is a rear view of a portion of the stringframe.

The strings A are secured at one end in any (N0 model.)

suitable way. In this instance .I have shown them attached to wrest-pins,which are prefero ably used, as by means of/them the strings may be brought nearly to tune, and thereby reduce any subsequent adjustment of the levers to the minimum. The strings A are secured at their other ends to the short arms of levers l3, hav- 5 ing their fulcrums' atb,and their long arms connected to the long arms of other lovers, 1%, having their fulcrums at i).

To the long arm of the levers B are attached weights O, which, by means of the compound leverage above mentioned, give the desired tension to the strings. The weights 0 are made of flat plates and quite lightsay about one pound eachso as not to obj eetionably in crease the weight of the instrument. Each plate 0 has small screw-threaded rods or wires 0 secured to its lower end. These rods 0 pass through perforations in a plate or board, 0, and are provided with nuts 0' below the board 0'. These nuts ciwhen the strings are properly 7o tuned, are screwed near to theboard 0, but not touching it, so as to leave sufficient space for the movement of the plate 0 incident to the contraction and expansion of the strings. By means of these rods cand the nuts 0, the plates O are prevented from becoming displaced or unduly moving when a piano is turned on end or otherwise in transportation. As above mentioned, the strings are very nearly tuned by putting on the weights, and if not in perfect tune they can be made so by means of the screws 1) in the ends of the levers B, adapted to turn but prevented from moving endwise, and bearing on the knife-edges of the fulcrums b of these levers, so that by turning these 8 5 screws their threads engage with the knifeedges, whereby the position of these levers in relation to their fulcrunis can be delicately and accurately adjusted, so as to increase or diminish the strain on the string to the slight o extent required.

It is evident that when the strings and weights are once properly adjusted they will remain so indefinitely, and the usual frequent tunings heretofore required in pianofortes 9 5 will not nowbe necessary. I have held pieces of red-hot iron in proximity to strings tuned 2. The combination, in a piano-forte, of the 10 inthis way, and Ihave also kinked such strings string, the compound levers, the weight, the with a pair of nippers without varying their screw, and the fulcrum having its edge adapttones in the slightest. ed'to engage with the thread of the screw, sub- I claim as my invention stantially as and for the purpose set forth. 1. In'a piano-forte,'the combination, with a I LOUIS G. THERRIEN.

I string, A, of the compound levers B and B I WVitnesses:

and weight C, arranged substantially as de- G. B. MAYNADIER, scribed, and for the purpose set forth. R. SNOW.

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