US828460A - Pianissimo action. - Google Patents

Description

PATENTED AUG. 14, 1906.

H. O. CLARK.

PIANISSIMO ACTION.

APPLICATION FILED AUG.22.1905.

Witnesses Attorneys THE NORRIS PETERS co, WASHINGTON, n cy UNITED STATES PATENT OFFICE.

PIANISSIIVIO ACTION.

Specification of Letters Patent.

Patented Aug. 14, 1906.

Application filed August 22, 1905. Serial No. 275,311.

To all whom, it may concern:

Be it known that I, HORACE O. CLARK, a citizen of the United States, residing at New York, in the county of New York and State of New York, have invented a new and useful Pianissimo Action, of which the following is a specification. I v

This invention relates to improvements in the construction of pianofortes.

In upright pianos of modern construction the depression of the soft or pianissimo pedal raises the action for thepurpose of lessening the stroke of the hammers, and this results in raising the lower ends of the lifters from contact with the rear ends of the keys or altering the distance between the jacks and the ham mer-butts. The spacing of the lifters above the key-rockers is objectionable in many respects and interferes With the touch, each key moving idly when first depressed and striking forcibly against the bottom of the lifter and raising the latter throughout the remaining portion of the key-stroke, and the resistance to the depression of the key is not the same as when the lifter rests on the key throughout the whole of the stroke of the latter. There is a further objection in that the upper end of the jack tends to catch against the hammer-butt and prevent the return of the parts to normal position after the sounding of anote.

To overcome the above-noted objections, provision is madefor connecting the keyboard to the pianissimo pedal and moving the same with the action each time the pedal is depressed, and at the same time means are employed for positively insuring return of the keys and preventin the binding action between the jacks and ammer-butts.

A further object of the invention is to so arrange and construct a pianissimo action as to permit its application to existing pianofortes without change in the construction of the key-frame, key-bottom, or any of the parts of the keyboard mechanism.

A still further object of the invention is to provide means for preventing any catching or jamming between the jacks and hammer butts when the soft pedal is depressed.

With these and other objects in view, as will more fully hereinafter appear, the inven tion consists in certain novel features of con struction and arrangement of parts hereinafter fully described, illustrated in the accompanying drawings, and particularly pointed out in the appended claims.

In the accompanying drawings, Figure 1 is a skeleton perspective view of an upright piano, illustrating the construction and ar rangement of the pianissimo action forming the subject of the present invention, parts being broken away in order to more clearly illustrate the construction. Fig. 2 is a transverse sectional view through the keyboard and the lower portion of the action. Fig. 3 is a detail elevation of one of the ornamental filler-blocks usually employed at the end of the keyboard and showing the manner in which the same is connected to the key-frame. Fig. 4 is atransverse sectional view of the same on the line 4 4 of Fig. 3. 5 is a partial transverse section illustrating a slight modification of the invention.

Similar characters of reference are employed to indicate corresponding parts throughout the several figures of the drawlngs.

The frame A of the pianoforte is of any or dinary construction, and the action includes the usual hammer-rail B, connected by a pin or rod C to the pianissimo or soft pedal D, the connection between the pedal and rod being formed by a lever E, so that when the pedal is depressed the rod will be raised and the hammer-rail elevated in the usual manner.

In nearly all upright pianos the keyboard is formed separate from the remaining ortion of the piano and is detachably hel in place on the key-bottom F. Thekey-frame 10, carrying the keys 11, may be slid into place and locked by filling-blocks 12, which may be of ornamental character. The board as a whole is arranged for movement simultaneously with the hammer-rail B and fol lows the latter in its vertical movement in order to maintain the relation between the keys and the lifters of the action. In the preferred construction the opposite end portions of the frame 10 are provided with projecting pins 16, that are entered in grooves 17, formed in the inner faces of the blocks 12, these grooves being of the construction best shown in Figs. 3 and 4 and each groove terminating in a seat or socket for the reception of a pin. When so supported, the rear end of the frame 10 is held very slightly out of contact with the key-bottom F, and the front edge of the frame is rounded, as indicated at 18, in order that the frame may swing on the pins 16 as a center without binding against the upper surface of the keybottom.

At the rear of the key-bottom is an openin 19 for the passage of a pin 20, that is provide bottom F at its lower end with a threaded the reception of a headed screw 21 to permit adjustment. The head of the screw rests on one end of a lever 22, that is pivoted on a hanger 23, carried by the frame, the opposite end of the lever being connected by a rod 24 to the lever E, and each time said lever is moved by the downward movement of the pedal D the pin 20 will be moved up and will elevate the key-frame and keyboard, so that the rear ends of the keys will follow the upward movement of the lifters and will always maintain their proper relative positions with respect to said lifters.

The screw 21 permits adjustment of the length of the pin 20 in order to compensate for wear or warping or distortion of the parts and permits proper movement of the key- 1 board as a whole, so that the keys will remainin contact with the lifters, and the key stroke and touch will therefore remain con stant without regard to depression of the pianissimo pedal.

It is found in some cases that there is danger of the jacks binding against the hannner butts when the hammer-rail is raised to diminish the stroke of the hammers, and in order to prevent this a bar 25 is placed over the rear ends of all of the keys. This bar is supported by a pair of threaded pins 26, the lower ends of these pins screwing into the keyand the bar being adjustable thereon by means of nuts 27. The lower face of the bar is covered with felt or similar cushioning material at the point where the rear ends of the keys strike, and said bar serves as a means for limiting movement of the keys when the pianissimo pedal is depressed and by preventing excess movement obviates the danger of binding between the jacks and hammer-butts. The pins 26, fur ther, serve as guides for springs 28, which bear against the rear portion of the key-frame and serve to force the latter downward when pressure on the pedal D is relieved.

In Fig. 5 is illustrated a slight modification of the invention, wherein the front bar 29 of the key-frame is provided with a rib 30, that enters a shallow groove 31, formed in the upper surface of the key-bottom and forms a fulcrum for swinging movement of the keyframe when the pedal is depressed.

In both constructions illustrated the keyboard is free to move to a limited extent in the direction of the length of the keys, so that during the upward movement of the keyboard. during the depression of the soft pedal there will be no binding between the rear ends of the keys and. the lower ends of the lifters, the relative positions of these members being preserved.

I claim 1. In a pianoforte, lifters, a key-bottom, a key-frame having its front end rounded and opening for Y resting on the key-bottom, to permit limited play in the direction of the length of the keys when the rear edge of the key-frame is raised, a pianissimo pedal, and. means operable from. the pedal for raising the rear end of said keyframe to preserve the relationship between the keys and lifters.

2. In a pianoforte, a key-bottom, a keyframe resting on the key-bottom and having a rounded front edge for engagement with such bottom, fulcrumpins projecting from the opposite ends of the frame near its front edge, supporting members having grooves in which said pins are loosely fulcrumed, a pianissimo pedal, and means operable on the de pression of such pedal for elevating the rear edge of the key-frame.

3. In a pianoforte, a key-bottom, a keyframe resting loosely on the key-bottom and having projecting pivot-pins at each end near the front edge, movable filling-blocks arranged at the ends of the frame and having slots in which such pins are loosely fulcrumed to permit ready detachment of the key-frame, a pianissimo pedal, and means for transmitting movement from the pedal to the rear edge of the key-frame.

4. In a pianoforte, a pianissimo pedal, a key-frame fulcrumed adjacent to its forward edge, means operatively connecting the rear edge of the frame to the pedal whereby the rear edge of the frame is raised when the pedal is depressed, and a bar extending over the rear ends of the keys and serving to limit the key-stroke when the keyboard. is elevated.

5. In a pianoforte, a pianissimo pedal, a keyboard operatively connected to the pedal and arranged to be raised when the pedal is depressed, threaded pins carried by the keybottom, a bar adjustably supported on said pins and extending over the rear ends of the keys, and springs encircling the pins and extending between the bar and key-frame, said springs serving to depress the keyboard when pressure on the pedal is relieved.

6. In a pianoforte, a key-frame fulcrumed adjacent to its forward edge, a pin extending through a guiding-opening at the rear of the keybottom and arranged to engage with the rear portion of the key-frame, an adjustable screw carried by the lower end. of said pin, a lever fulcrumed under the key-bottom, and arranged to engage said pin, a pianissimo pedal, and means for connecting said lever to said pedal.

In testimony that I claim the foregoing as my own I have hereto affixed my signature in the presence of two witnesses.

HORACE O. CLARK.

I/Vitnesses:

J. H. J OOHUM, J r., J NO. E. PARKER.

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