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Publication numberUS633915 A
Publication typeGrant
Publication dateSep 26, 1899
Filing dateMar 14, 1899
Priority dateMar 14, 1899
Publication numberUS 633915 A, US 633915A, US-A-633915, US633915 A, US633915A
InventorsAndrew J Smith
Original AssigneeHerbert Griswold, Andrew J Smith
Export CitationBiBTeX, EndNote, RefMan
External Links: USPTO, USPTO Assignment, Espacenet
Key mechanism for musical instruments.
US 633915 A
Abstract  available in
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Claims  available in
Description  (OCR text may contain errors)

No. 633,9I5. Patented Sept. 26, I899. A. J. SMITH.


(Application filed m. 14, 1099.

(No Model.)


UNITED STATES l rrjrnn r @rricn.



SPECIFICATION forming part of Letters Patent No. 15, dated $e13te111bel 2 1899- Applioation filed March 14, 1899. Serial No. 709,005. (No model.)

To all whom 5/; may concern:

Be it known that 1, ANDREW .l. SMITH, a citizen of the United States, residing at Spring field, in the county of Sangamon and State of Illinois, have invented certain new and useful Improvements in Key Mechanism for Musical Instruments, of which the following is such a full, clear, andexact description as will enable others skilled in the art to which it ap pertains to make and use my said invention.

My invention relates to musical instru ments of that classsuch as pianos, organs, &c.- which have keys which may be manipulated to produce various musical notes.

The purposes of my invention are to provide simple and effective means to prevent sticking of the keys and to provide means whereby the accumulation of dirt within the instrument may be avoided.

With these ends in view my invention consists in certain novel features of construction and combinations of parts shown in the annexed drawings, to which reference is hereby made, and hereinafter described, and pointed out in the claim.

Referring to the drawings, Figure 1 is a side elevation of the complete mechanism. Fig. 2 is a top plan view of a part of the guiderail carrying the guides or eyes in which the guide-pins work. Fig. 3 is a vertical section through the guide-rail on the line 3 3 of Fig.

2. Fig. 4: is a vertical transverse section through one of the keys on the line 4 a of Fig. 1. Fig. 5 is a horizontal transverse section through one of the guide-pins on the line 5 5 of Fig. 1, looking downward, and shows in top plan one of the eyes or guides in which the guide-pins work.

Similar letters of reference designate like parts in all of the views.

In the drawings I have shown only one key, it being understood that there are a number of keys, all exactly alike and arranged side by side.

In order that the nature of my invention may be clearly understood, I will state that prior to my invention of the improvements herein described the common practice has been to guide the keys by means of vertical guide-pins immovably secured to a rail underlying the keys near the front end thereof, the upwardly-projecting ends of the pin fitting in longitudinal felt-lined mortises in the lower part of the keys. The keys being commonly made of pine or other light and porous wood, it is found in practice that when exposed to moisture the wood swells, thereby contracting the mortises in the keys to such extent as to cause the pins to bind in the mortises, and thereby prevent free movement of the keys. One of the main purposes of my invention is to overcome this dilliculty, and I accomplish this result by securing the guidepins rigidly on the keys and forming the eyes in which the guide-pins work on a sill or rail of metal or other non-porous or non-absorbent material which will not swell when exposed to moisture.

The guide-rail A, the center rail 13, and the rear rail D are supported on and suitably secured to two or more sills C, transverse to the instrument in which the key mechanism is employed. Vertical pins B, one for each key, are secured at suitable distances apart on the center rail 13. A felt washer B surrounds each of the pins B". A longitudinal felt cushion D is cemented or otherwise secured on the upper surface of the rear rail D.

The boxshaped guide-rail A is made of metal or hard rubber or indnrated fiber or other material which will not swell to a deleterious extent when exposed to moisture.

yielding and sound-deadening material, are

cemented or otherwise suitably secured to the side walls of the openings a.

In order to prevent the accumulation of dirt on the rail A, it is made foraminous, as clearly shown in Fig. 2. lhe precise form of the openings in the rail is immaterial, and

they may be made of any form adapted to lighten the rail without unduly im 'iairing its strength.

The key proper, E, is preferably of pine or other light wood. A finger plate E, of ivory or othersuitable material, is suitably secured to the key E.

The guide-pin is preferably in crossseo tion elliptical in form and for a part of its length is-preferably screw-threaded, as at c, and screws into the key E.

The pin E is made of elliptical cross-section, as described, in order that when the felt linings a in the eyes a become worn to such ex tent as to permit undue lateral motion of the pins in the eyes the pins may be turned slightly, so as to compensate for the wear,an d thus obviate the necessity for replacement of the felt lining a.

I do not confine my claim to a pin of elliptical cross-section,since it is obvious that pins of any other form of which the cross-section is a curve having a major and a minor axis may be used. Neither do I confine my claim to a screw-threaded pin, since it is obvious that other means maybe employed for turnably connecting the pin with the key. It is essential only that the pin shall be turnable and that it shall be of such form that when turned the transverse measurement of the pin shall properly correspond to the trans verse distance across the eye in which the pin slides.

A 'felt washer E surrounds the pin E and is secured to the under side of the key It.

'When the key is depressed, the washer abuts against the upper surface of the boss A.

An adjustingpin F screws into the key E. The key E is pierced between its extremities by a vertical slot 0, (shown in. dotted lines Fig. 1,) through which the pin 13 passes. The slot e is longer at the top than at the bottom in order that the key may oscillate freely on the washer 13 without striking against the pin.

A suitable number of suitably placed weights E", of lead or other heavy material, serve to balance the key in such manner as to make it properly responsive to the touch of the person performing on the instrument.

Having fully described my invention, what I claim as new, and desire to secure by Letters Patent, is

In key mechanism for musical instruments, the herein-described box-shaped foraminatcd guide-rail provided with bosses having eyes bushed with sound-deadening material, in combination with oscillative keys and oval pins on said keys registering with and turnable for transverseadjustment in the eyes of said guide-rail, as set forth.

In witness whereof I have hereunto subscribed my name, at Springfield, Illinois, this 8th day of March, 1899.




Referenced by
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US6531651 *May 2, 2001Mar 11, 2003Kabushiki Kaisha Kawai Gakki SeisakushoKey for musical instrument
US7186907Apr 22, 2005Mar 6, 2007Asami InouyePiano key assembly
US7633002Mar 6, 2008Dec 15, 2009Asami InouyePiano key assembly
US9070346 *Aug 12, 2013Jun 30, 2015Kabushiki Kaisha Kawai Gakki SeisakushoWhite key for keyboard instrument
US20050235804 *Apr 22, 2005Oct 27, 2005Asami InouyePiano key assembly
US20090223347 *Mar 6, 2008Sep 10, 2009Asami Inouyepiano key assembly
US20140083277 *Aug 12, 2013Mar 27, 2014Kabushiki Kaisha Kawai Gakki SeisakushoWhite key for keyboard instrument
DE102008023860A1May 16, 2008Sep 17, 2009Asami InouyeVerbesserung der Klaviertastenbaugruppe
Cooperative ClassificationG10C3/12