US2436875A - Piano action - Google Patents

Description

March 2, 1948. C 505; 2,436,875

PIANO ACTION Filed March v23, 1945 2 Sheets-Sheet l mmvroze.

March 2, L948. F. c. SOCIN 2,436,875

PIANO ACTION Filed Mar ch 23, 1945 2 Sheets-Sheet 2 INVENTOR. 15a few/v0.5 6 50cm BY I ,7 rams 115.

Patented Mar. 2, 1948 PIANO ACTION Francis 0. Socln, Batavla, Ill., asslgnor to The Rudolph Wurlitzer Company, Chicago, 111., a

corporation Application March 23, 1945, Serial No. 584,353

Claims. 1

This invention relates to a new and improved direct blow piano action, particularly adapted for use in low upright spinet type pianos.

It is the object of the invention to provide a direct blow action of compact construction such as will enable its use in a low spinet type piano where it is desired that the striking point of the hammer be at a minimum distance above th key bed.

One feature of the invention resides in the construction and relation of the wlppen with respect to the striking action of the key coupled with a laterally extended flexible jack. Thus, it com prises a direct blow type action, all as will be more fully set forth and described in the following specifications.

Another feature of the invention resides in the provision of a double acting spring in association with the hammer butt to assist and accelerate the hammer let-01f and return to rest position; and to equalize the movements of the action to provide for positive and smooth acting repetitive qualities in cooperation with the associated spring or springs as hereinafter described.

The full nature of the invention will be understood from the accompanying drawings and the following description and claims:

Fig. 1 is a side elevation showing a unit of the action in its rest position.

Fig. 2 is the same as Fig. 1 showing the action in striking position.

Fig. 3 is the same as Fig. 1 showing a modified form of unit.

Fig. 4 is a partial view showing a further modification of the unit.

In the drawings there is shown a key bed ll] upon which a piano key H is pivotally supported in the usual and well known manner. The key is provided at its operating end with a striking head l2 rounded to slidably engage the cushion bed pad l3 carried by a finger l4 through which the striking action is transmitted to a vertically extending wlppen l5.

The wippen I5 is pivotally supported adjacent its lower end at" I5a upon a lower flange rail I 6 of a supporting frame by the flange I 1 and at its opposite upper end is pivotally connected at l8 to the finger i4. Said finger has an extension 19 through which a screw threaded button 20 extends for adjustment to and from the striking head of the key. The pad l3 supported on the lower end of the finger I 4 adjacent the end of the key H extends over and between the striking head and the button. Thus, the striking head imparts a direct blow through the adjustable button 20 and finger M to the wippen such as to cause a forward striking action of the wippen.

. The hammer 2| is mounted in alignment with the piano string 22 being carried by the arm 23 extending from the end of one arm of an L- shaped hammer butt 24. The other arm of the hammer butt 24 is pivotally mounted by the flange 25 upon the flange rail Hi. In rest position the hammer lever rests upon the cushioned back rail 26. The striking movement of the wlppen is transmitted to the'hammer through the hammer butt by a flexible jack. Said flexible jack comprises the jack member 2'! pivoted at 28a to the wippen intermediate its ends. This member of the jack is pivoted to a link member 28, which in turn is pivoted at 2827 to the hammer butt intermediate its arms. The general relative arrangement and position of the jack is at an angle ex tending downwardly and laterally from the wippen to the hammer butt. I

Said jack is provided with a heel portion 29 adjacent its pivotal mounting 28a for engagement with the regulating button 36 adjustably carried upon the rail 3!. That arm of the L- shaped hammer butt, which is pivoted to the flange rail, is provided with a let-off bumper 32 engageable with the pivotal connection between the link member 23 and jack member 21.

The flange ii for pivotally supporting the wippen carries a spring arm 33 bearing against the forward face of the wippen near its pivotal connection with the jack, said spring arm 33 tending to return the wippen to rest position. Also, carried by the wippen there is a spring arm 34 extending along the under side of the jack member 27 with its free end connected thereto, which tends to return the flexible jack to its rest position. Also, mounted upon the upper end of the wippen there is a back check 35 engageable by the hammer in its let-off position shown by dotted lines in Fig. 2.

The damper 36 is carried by a damper arm 37 rigidly mounted to extend directly upwardly from the'damper lever 38. Said lever 38 is fulcrumed intermediate its ends upon the support flange 39 mounted upon the flange rail I 6. Said lever is actuated by the actuating finger 40 mounted on the lower end of the wippen below'its supporting flange l1. Thus when the wippen is struck forwardly, the finger 40 swings downwardly against the lever 38, which in turn swings the damper arm 31 rearwardly, carrying the damper free of the string, said damper being returned to dampening position through the sprin 4 I. Said spring 4| is secured to the flange 39 and has its free end extending over and bearing upon the end, of the damper. lever carrying the damper arm 31.

The action is such that upon actuation of the key its striking head imparts an upward movement to the finger I4, which, being pivoted to the upper end of the wippen, drives it forwardly. Since the flexible jack is normally in overcenter position its: forward-andiaownward'fmovement imparts a correspondingzmovement toz-the hammer.

butt, swinging it forwardly and downwardly to throw the hammer into striking engagement with.

throws the let-off bumper 32 againstithepivoted connection between the jack members;.wherebythe jack is flexed to permit the let-off of the hammer to the dotted line position, Fig, 2. Upon the key returning to rest position, the spring 33"will cause the wippen to follow it and the spring 34 will return the jack toits rest position. Said springs 33. and 34, coup1ed-with thefiexing, of the jack,- gives the. action .the, desired: doublerepetition;.

The double repetition action is furthered by providing-a spring-Sfl-havingaa separateend anchoredto the spr-ingrail'r5l-. and its lower end bearing againstethe-rupwardly extending arm of therhammer. butt 2'4 The-spring rail 5! is positimed to act asza .bufier; orstop for the damper 36-, the-"spring:dependingtherefrom and bearing against. the; hammer: butt. tending: to oppose the- I striking: actiomoi: the hammer: Under the-tension ofj said'springthe; let-oft: action of. the hammer following; the blowsis facilitated, the Spring assisting the natural; recoil; thereof. Also, when the:.harnmer isgin check-against the back check 35,.said spring: partially equalizes the, tension of theispring 34 intreturningthe flexible, jack to rest position. The" equalization ofzsaid' spring eliminates any violent kickbackofithei-fiexible jack as thehammer and" jack: are-returned to, rest position: their; pressureon-the-keys, ,thehammer. is thrust gently towarckthestring but not enough-to touch it,,. at the same time the flexiblejackbeing gently but positively-returnedto normal or restposition, whereby, ther; performance of; the action. becomes typical of that otagrand piano. action generally referred to as-asdouble repetition.

Fig. ,3. shows a: modifi'ed-formofthe above described {action wherein adoubleacting; spring I56 is removably anchoredand supported at one end by the pin; ISZprQV-ided in adownwardly extending heel l53iformed on.the-;hammer;butt I24. Its upper endis anchored to the-spring rail 5|. The springis formed L -shapedabout a coil I54 formed therein intermediateitsaends;

That-portion;otthegspring betweenthe rail 5| and'itscoil l'54'acts as, a floating spring arm permitting;lateralmovement of the coil- The portion thereof extending from said; coilto the, pin i521 exerts? an: upward pressureon the hammer butt; 24: about; its'spivotalisupporton" the. rail Hi. This; action: assists the let-off. and=return of the hammerrto rest-position. Thisresultsin. a much smoother, frictionless: action: t'ozthez escapement. I

Fig: 3: furtherillustrates; the;v provision: of; an elongatedtfinger I-l kwhichiis in: the nature of fan adapter-for. accommodating theactionto a larger size; pianoionrcasey Thuszin Fig; 3' thezaction is shown raised somewhat; with respect to the key bed lllandpiano key: H; Withthis arrangement the elongated finger or" adapter: I .l 4 is: pivoted to the-wlpnem H3 at H 8:-.adjacent:its: upper end and is provided:witlrtha-extension; Ii 9 throughiwhich" Thus;v as; the performers fingers release the screw threaded button I20 extends for adjustment to and from the elevated striking head H2 mounted upon the key. The end of the adapter finger ll i carries a cushion pad I I3 and the button I20 carries a similar but separate cushion pad Il3-A. However, said pads may be joined as in one piece as illustrated by the pad l3 of Fig. 1. V

In the modified form. shown in Fig. 4, the wippen 2 I5. is actuated by'a bell crank in place of the finger 1-4, the bell crank having an upstanding finger 2! associated with the upper end of thewippen and positioned to strike it forwardly through the medium of the pad 2E3. The angularly and laterally extending portion of the bell crank, lever indicated at 22B is directly engaged through apad 213 by a capstan screw 212 carried by the striking end of the piano key 2| I. The bell crank lever is pivotally supported intermediate its ends on the upper flange rail 2l9 of the supporting frame through pivotal flange support 2l9-A. Thus, the key is actuated and strikes upwardly against the arm 220 of the bell crank lever, throwing the upstanding finger Zi thereof laterally against the upper end of the wippen 2i 5 for transmitting such lateral swinging movement of. the

wippen to the hammer through theflexiblejack.

The invention claimed is:

1. A piano action including a piano key, a hampositioned to strike the piano string,.a supporting frame, a wippen pivotally mounted at oneend upon said frame below said key to extend substantially vertically with respect to and terminating above said key, a striking member. associated with the upper end of said wippen engageableby the striking end of said key to swing said wippen forwardly toward the string, a hammer butt pivotally supported by said frame carrying said ham mer on one end thereof, a jack pivotally connected with said wippen intermediate-its ends andexetending downwardly and forwardly toward the string into operative engagement with said hammer butt for transmitting the striking action of said key therethrough to said hammer, and a 1. spring anchored to said frame extending upwardly into engagement with said wippen intermediate its ends tending to return it to rest position after being actuated.

2. A piano action including a piano key, a ham.- mer positioned to strike the piano string, a supporting frame including a lower flange rail and an upper flange rail, a wippen pivotally mounted on said lower flange rail below said key to extend upwardly thereabove, a jack pivotally mounted on said wippen intermediate its ends for operative engagement with said hammer to transmit movement therebetween, and an actuating finger-piv otally mounted on said upper flange rail interme diate its ends having an upstanding portion associated with the-upper end of said wippenand a.

laterally extending portion overlyingthe striking end of said key through which upwardmovement of said key will transmit lateral movement to the upper end of said wippen.

3. A piano action includinga piano key, aham= mer positioned to strike the piano string, a supporting frame including a spring rail, a wippen pivotally mounted upon said frame, a striking finger associated with said wippen engageable-by:

the striking end of said key-to swing said wippen about its pivotal mounting, ahammer'butt pivotally supported by said frame carrying a hammer on one end thereof, a jack engaged with saidwippen intermediate its ends and extending into 0p erative engagement with said hammer buttnfor transmitting the striking action of said key therethrough to said hammer, and a double acting spring interposed between the spring rail of said supporting frame and said hammer butt tending to return said hammer from said string to implement its let-off action, said spring being formed with a coil intermediate its ends to provide a floating spring arm.

4. A piano action including a piano key, a hammer positioned to strike the piano string, a supporting frame including a spring rail, a wippen pivotally mounted upon said frame, a striking finger associated with said wippen engageable by the striking end of said key to swing said wippen about its pivotal mounting, a hammer butt pivotally supported by said frame carrying a hammer on one end thereof, a jack engaged with said wippen intermediate its ends and extending into operative engagement with said hammer butt for transmitting the striking action of said key therethrough to said hammer, and a double acting L- shaped spring formed with an intermediate yielding formation intermediate its ends to provide an upwardly extending floating arm with its upper end connected to said spring rail, and a laterally extending arm connected to said hammer butt, to thereby assist the let-off and return of the hammer to rest position.

5. A piano action including a piano key, a hammer positioned to strike the piano string, a supporting frame including a spring rail, a wippen pivotally mounted upon said frame, a striking finger associated with said wippen engageable by the striking end of said key to swing said wippen about its pivotal mounting, a hammer butt pivotally supported by said frame carrying a hammer on one end thereof, a jack engaged with said wippen intermediate its ends and extending into operative engagement with said hammer butt for transmitting the striking action of said key therethrough to said hammer, a spring having one end anchored on said wippen and its opposite end connected with said jack tending to return said jack to normal rest position after actuation, and a double acting spring interposed between the spring rail of said supporting frame and said hammer butt tending to return said hammer from said string to implement its let-off action, said last mentioned spring being formed with a yielding formation intermediate said frame and butt to provide a floating action therebetween.

FRANCIS C. SOCIN.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 172,621 Frickinger Jan. 25, 1876 326,576 Merges Sept, 22, 1885 2,153,226 Zeidler Apr. 4, 1939 2,266,990 Martin Dec. 16, 1941 2,305,037 Schulze Dec. 15, 1942 2,329,009 Socin Sept. 7, 1943 FOREIGN PATENTS Number Country Date 461,445 Great Britain Feb. 17, 1937

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