US3169436A

US3169436A - Piano action

Info

Publication number: US3169436A
Application number: US301827A
Authority: US
Inventors: Charles F Smith
Original assignee: Individual
Current assignee: Individual
Priority date: 1963-08-13
Filing date: 1963-08-13
Publication date: 1965-02-16
Anticipated expiration: 1982-02-16

Description

Feb. i6, 1965 c. F. SMITH PIANO ACTION Filed Aug. 13, 1965 .Zava-nim" E A Char/es AC Sm/'/y /aZ/M, 2a, m M

YY 4 1r a, v. A .i In n United States Patent g Office n 3,169,436 PIANO ACTION Charles F. Smith, 835 Circle Ave., Forest Park, Ill. Filed Aug. 13, 1963, Ser. No. 301,827 4 Claims. (Cl. sfr-243) The present invention relates to an escapement action for a grand piano. f n

Escapement actions have followed a standardized construction for many years. In this structure, the jack contacts the hammer knuckle and lifts it to raise the hammer against the string. YThere has long existed a problem with respect to friction kdrag betweenthe jack and the knuckle. This friction'drag results in sluggish action of the keys, and obviously adds to the inertia. Considerable linger strength must'be developedv for playing the piano over long periods of time. Furthermore, a very soft tone cannot be struck in a reliable manner because the player cannot be completely sensitive to the extent of the friction drag.

It is an object of the present invention to provide an improved construction which will minimize the friction betweenthe jack and the hammer knuckle.-

A further object of the invention is to provide an adjustment whereby the amount of friction drag between the knuckle and jack can be readily changed and regulated. Some piano players, particularly professional artists, have become accustomed to full friction drag between the jack and knuckle and have developed such finger strength that any change in this drag would be objectionable to them. In order to met the requirements of such persons,

my invention permits the adjustment of the frictionl drag;

In the accompanying drawing: Y

FIGURE 1 is a side elevation of a grand pianoV escapement action; y

FIGURE 2 is a side elevation of the hammer butt,

' knuckle and spoon for positioning the jack with respect to the knuckle; n f FIGURE 3 is a front elevation, partly in cross section of the hammer butt, knuckle and spoon for positioning the jack;

FIGURES 4 and 5 are side elevations, partly in crossl section, of the kunckle and jack andrassociated parts.

base 11 also carries a balance rail 14 which supports aV plurality of balance key pins 15. The'keys 16 are held in position by the felt washer 17. The back end of each of the keys 16 carries a felt pad 1S adapted to engage the f damper lever which is carried by the bracket or frame 19.

Each key is provided with a capstan screw 21, positioned at an intermediate point between the rear extremity of the key 16 and the balance vkey pin 15. The capstan screw 21 bears against a felt surface 22 carried by a dependent portion '23i`of a whip or wippen Z4. The wippen 24 is' supported at its rear end by a whip flange 2SV which is securedV by aV screw Z6 to a whip railZ'i. The whip rail 27V is secured to the bracket or frame 2.8.

The forward extremity of the whip 24 is pivotally conV nected to the jack'29', intermediate thetwo ends of the f jack. A jack regulating screw 30 vis carried by the jack.v This screw 30 has a jackV butt 31 which contactsk the to control the amount of friction drag betwen the knuckle spoon or stop 32.. r

The whip'23 carries a repetition lever flange 35. Piv- Patented Feb. 16, 1965 otallyconnected tothis iiange is a repetition lever 36, one end of whichv carries a regulating screw 37. Adjacent the forward extremity of the repetition lever 36 there is an opening through which passes the upper end of the jack 29. Both the jack 29V and the repetition lever 36 engage a knuckle 38, which is carried by the hammer butt 39. The hammer butt 39 is pivotallyv connected to a butt flange di), which is mounted on the hammer rail 34. The hammer butt 39 extends rearwardly to a reduced diameter portion known as a hammer stem 41.

The hammer stern lll'carriesV at its outer` extremity a hammer 42 which, when raised to the dotted line position shown in FIG.y 1, will strike the piano string 43. Wheny a key is struck and held down, the back check 44 carried 1 at the rearend of the key 16 is raised to limit the downwardk motion of the hammer d2. n

The forward or outer end ofthe repetition lever carries a button ltwhich strikes a stop 46 positioned on the hammer flange during upward movement of the repetition n lever. A spring 47 is connected to the repetition lever and the jack, as shown in FIG. 1. The tension of vthe spring urges the repetition lever upwardly and urges the 7 jack under the knuckle.

The foregoing parts constitute the standard or common grand pianopaction. In accordance with the present invention I modify this standard action by providing a positioning member 48 extending downwardly immediately rearwardly of the knuckle 3S. This positioning d member or spoon serves to position the jack away from the spoon or ystop 32 whenthe key is released. On the next stroke, therefore, the jack is not held against rear- FIGS. 4 and 5 illustrate the position of the knuckle, jack and positioning member just before and just after the escapement of the jack from under the knuckle.

The operation of the action is as follows: VWhen the key is depressed the jack V29 raises the knuckle andtheharnmer stern so that the hammer 42 hits the wire 43. The hammer rebounds and is caugnt by the back check 44. The jack 29, in its upward movement, has struck stop 33 causing the opposite end to move sharply out from under the knuckle to a forward position as shown in FIG. 5. The repetition lever 36 is depressed by reason of its movementA against stop 46.

When the key is release, vthe back check 44 is lowered and no Vlonger supports the hammer; The repetition lever 36 supports the hammer at this Vpoint so that the jack can move back under the knuckle rfor the next stroke. As the` jack moves rearwardly under the knuckle, yits movement is checked by the contact of the button 31 with the spoon 32. As the hammer stern dropsk into its lowest'position the spoon or positioning member 43 con-` tactsrthe jack and moves it forwardly so that the botton .31 is clear ofspoon 321.' With the jack thus positioned clear of the spoon 32, thejackV contacts the knuckle is only one position on upward movement, and does not slide across the surface of the knuckle.

By adjustment of the screw 30 the amount of clearance between the button 31 and the. stop 32 can be regulated and the jack. If a pianist accustomed to playing with the old friction drag desires such drag, it can be provided in fuller to the desired degree.

It is to be understood that the invention is not limited to the particular embodiment which has been described and shown in the drawing, and such variation in the construction may be made as is commensurate with the scope of the invention as set forth in the following claims.

What is claimed is:

1. The combination in a grand piano action comprising a hammer butt carrying on its underside a knuckle, a repetition lever and jack arranged to actuate said hammer butt by engagement with said knuckle, and means on said hammer butt for engagement with said jack to position said jack under said knuckle.

2. The combination in a grand piano action comprising a hammer butt carrying a hammer, a knuckle mounted on the underside of said butt, a jack, a whip, a a stop mounted on said whip for limiting the movement of said jack, and a member on said hammer butt for engagement with said jack whereby said jack may be moved clear of said stop.

3. In a grand piano action comprising a hammer butt having a knuckle on its underside, a repetition lever and jack arranged to actuate said hammer butt by engagement with said knuckle, the improvement which resides in the provision of a spoon on said hammer butt for engaging said jack to position the jack under the knuckle.

4. In a grand piano action comprising a hammer butt having a knuckle thereon, a repetition lever and jack arranged to actuate said hammer butt by engagement with said knuckle, the improvement which resides in the provision of an adjustable stop member for limiting the movement of said jack, and the provision of a spoon on the hammer butt for positioning the jack with respect to the stop.

References Cited by the Examiner UNITED STATES PATENTS 32,863 7/61 Frickinger 84-23'7 49,394 8/65 Farholtz 84--237 717,349 12/02 Charpiat 84-237 1,097,696 5/14 Werolin 84-237 1,215,489 2/1'7 Conover 84-239 2,267,538 12/41 Socin 84--239 LEO SMLOW, Primary Examiner.

Claims

1. THE COMBINATION IN A GRAND PIANO ACTION COMPRISING A HAMMER BUTT CARRYING ON ITS UNDERSIDE A KNUCKLE, A REPETITION LEVER AND JACK ARRANGED TO ACTUATE SAID HAMMER BUTT BY ENGAGEMENT WITH SAID KNACKLE, AND MEANS ON SAID HAMMER BUTT FOR ENGAGEMENT WITH SAID JACK TO POSITION SAID JACK UNDER SAID KNUCKLE.