CA1224950A - Action for upright piano - Google Patents

Abstract

An action for an upright piano which emulates or simulates the action of a grand piano is provided. In the action, a back check lever is positioned above the back of the key, and a grand piano whippen is positioned above the back check lever. The grand whippen acts on a knuckle provided on a catcher arm integrally connected with the hammer shank at a substantial angle. Depression of the key produces upward movement of the back of the key, the back check lever, and the grand whippen, in turn producing rotation of the catcher arm which drives the hammer towards the string. The catcher arm has a catcher at its forward end and the back check lever has a hack check for catching the catcher after the hammer has rebounded from the string. A damping action is mounted independently from the hammer action.

Description

Titl.e~ I'IOh FOR l~P~lGllT f'LAh~

.[nventor: Pau,L GerharcL W.al.l, oi' Ki.t,chenert Ontarlo, (',anada B~KGMOUND OE~ HE INV_N'l'LON
'L'his i,nvention rela-tes to an act:ion f'o:r an upr:i,gh-t piano~ the ac-tion be~n~ the mechanism which transm:its the impetus given by the player's -touch to the pi.ano strings.
An i.dea:l p:i.ano ac-t:ion would have -the f'ol:Lowing 5 characterist:ics: Firs-tly, the piano player shou:Ld have good contro:l over the hammer blo~, in order to be able t.o vary the character of the no-tes played. Second:Ly, -there must be escapement so -that the harnmer can rebound freely after striking -the 9 tring, even i.f -the key is stil:L being 10 d.epressed by the player. Thirdly, the motion of' the hammer shoul.d be cheaked after i-t has rebounded from -the s-tring.
:Fourthly, the player should be able -to :repeat -the note immediately and continuously it' desi.red, even if the key is not :thlll.y released. .E~`i:l'thly, the damping a.ction should be 15 instantaneous and silent.
Diff'erent p,iano actions approach these ideals to va:ry:ing deg-.rees. The ac-tion of a grand piano is generally considered to much more cLose.ly approach these ideals than the ac-tion of' an upri.ght pi.ano. For example, the grand 20 p;"ano ac-tion a.L:Lows :t'or immediate and continued repetition of a note, even i.f the key has no-t fully re-turned -to its normal (undepressed) positi.on, whi:l,e the upright action requires that the key return to or almost to its no:r.~mal posi-tion be-t'ore the note can be repea-ted. This dit'ference `~

is clue to the superior d~si~n o~ the grand plano ~hippen assen~bLy.
The conventional uprl~ht piano actLon has a singrLe simpLe escapement, tha-t of -the hammer trom the jack of the whippen assembly. Ttle head of the jack is ordinarily in contac-t wi-th the bu-tt of the hammer. When the key is depressed the jack is moved upward:Ly, forcing the bu-tt o:f -the hammer -to rotate upwardly about the pivot poin-t on its flan~e. ~t a certain point bef`ore the nammer contacts the string, escapement takes place. The jack rotates out -from utlder -the bu-t-t oi`-the hammer, freeing the hammer to continue under its own inertia towards the string and to rebound freeLy a~ter impact. After rebounding :~rom the string, the ca-tcher is caught by the backcheck and held in this posi-tion as long as the key is depressed. In order ~or the no-te to be repeated, -the key must be -fully released or very near]y so, so tha-t -the jack can drop back in-to pos:ition under -the hammer butt.
By contrast, in the grand piano action the jack 20 can drop back under the knuckle before the key is fully released. In a grand piano action, there is a compound escapemen-t, involvlng the jack coming into contact wi-th a regulating button and be:ing forced to rotate out from under -the knllckle o~ the hammer, al~d also the repeti-tion lever 25 comin~ in-to contact with a drop screw. As the key is depressed, -the escapement -takes p:lace and the hammer f`lies :treely towards the string under i-ts own iner-tia. A-~-ter reboundi.ng from the string, the catcher :is caught by the backcheclc and he:Ld in this position as long as the key is 35~) depressed. Then, when -the key is released slightly, the repet~tion lever supports the knuck:le, allowing the jack tc>
drop bacli into pos:ition. Consequently, if the key is c3epressed again, the jack~ can immediate:ly move upwards and 5 attack the knuck]e. Repea-ti,ng a no-te immediately and continl~ously is thus -far easier than on an upri~ht piano.
Checking in a grand piano action must generally be more secure than in an upright action, due -to the force in the direction of` the string exerted by -the repet:i-tion lever 10 on the knuckle on -the hammer shank.
Wi-th respect to damping in a grand piano, the damper is he:Ld onto the s-tring by gravity. ~s soon as the Isey is released, the damper starts to drop back onto the string. The damper is a:Lso under the direct control of the 15 key. When the key is depressed the ef'fect produced by gravity on the damper must be overcome. The f`act that the damper is under direct control of -the key and that the damper is held on the s-tring only by gravity gives the grand piano a precise -touch which is appreciated by many players.
By con-trast, the damper in -the upright piano is held onto the string by means of a small damper spring.
When -the l~ey is depressed -the force e,Yerted by -the spring on the damper must be overcome. Overcoming -this f`orce is a gradllal process and the touch of'-the uprigh-t piano keys is 25 oonsequen-tly somewhat dit'f'erent from that of'-the grand piano. I'he spring may also deteriorate with time and thereby produce an inconsistent touch. If sufficien-t deterioration occurs, the damper may be lef-t in imperf'ec-t contac-t with the string, -thereby reducing its abili-ty to ~2~5~
damper) st:ring ~ibration. Also. the damper is not under the di.rect c~ontrc).l of` tt)e key but ra-ther is activa-ted via an in-l-,ermedia-te lever. These :f'~ctor~ resul-t in a damper action which ha.s a :less conl,rol:Led and con~i.sten-t touch and which 5 is more prone to Inechanic~al problems than -the damper action in a. grancl pi.ano.
:In addit,ion t,o sllperior note repet.it,ion, -the orand piano acti.on ha.s an advan-tage over the upright p:iano action in relation to the operation ot' the .left or soft pedal, la.rgely due -to the -Eact -tha-t -the hammer and damper actions are s-t.ructurally i,ndependen-t of each other.
In the g:rand piano, when the left peclal is depressed, -the key:t`rame s:Lides .la-terally on -the Iceybed. '['he hammer a,c-tion is attached -to the keyframe, and consequently i,t also slides lat.era:i.ly ~hen the soft pedal is depressed.
T f' a key in the treble section is p:Layed, -the hammer ordi,narily strikes three strings. Ilowever, i.-t` the key is played whi:Le the sof't peda,l is being depressed, the hammer wilL move latera:lly with -the keyframe and strike only -two strings. A ~ofter sound w:i.ll consequen-tl.y be produced.
Tn a conventional upright piano, movement of the key:;rame i.s not posslble, because the dampers are attached to the ma:in action ra,i:L, as are -the hammer t':Langes. Si,nce -the dampe~rs must not move :in relation -to the strings ~because they must be seated properly on the stri,ngs in order to d.ampen string vibra-tion), this means -t:ha-t the hammer ac-tion, be:ing supported on -the same main ac-tion raiL~ cannot move with respect to the strings. By contrast, in -the grancl pi,ano, -the dampers are at-tached -to a damper flange rail whic.h -is independe:nt f'-rom t,he main ac-tion rai.l. 'I'he keyframe can there~ore t)e made f'ree to move l.a-teraLly when the soft pedal j a, used ~ l thou-t having -the da.mpers sl1i.f't, :[n ~ convent1onaL up:l~i,ght piano, softening is achieved by having the hammer rail move the hammers closer to the strings when t,he sof't pedal is depressed. I:f a key is played with -the soft peda:l depressed, some o:f the mo-tion normal:ly impa~ted -to the hammer is ,Los-t because o-f' the shorter distance between the hammers and -the s-trings and because of 1;he shorter period ol` contact between the jack and the hamme:r butt. resu:Lting f'rom the shif`ting of -t.he hammer raiL, so the hammer strikes -the s-t.rings wi,-th :Less force than normal. ~ hammer in the -treble section of -the pi,ano will, normaLI.y strike three str:ings, bu-t will strilse them with ,less t'orce -than usual when the soft peda:L is used, and wi.,L:I theref'ore produce a sof'te-r sound.

Si~MMARY OF l`HE :tNVEN'I'ION
I-t is an objec-t of the present invention -to provide an action for an upri.ght piano whi.ch emula-tes or si.mu:Lates the grand. piano action. The ac-tion a,Llows no-tes to be repeated even when the key has not ful,l.y re-turned to its norma,l positi,on, and beca.use -the hammer action and.-the damper act:ion are :independent, allows the keyframe -to move ,I,atera:L:Ly ~hen -the so:t'-t pecla:L is depressed.
In the ac-tion of the presen-t inven-tion, the 25 conventional upright piano whippen and hammer bu-tt have heen replaced with ones such as those in -the grand piano. Thi,s a:L:Lows for immediate and continued repe-tition of' no-tes. The da.rnper and hamme:r of -the -pr~esent ac-tion are not :located on the same action rai:l, bu-t rather a:re set Up independen-tl.y on their own action :rai..ls. rl'his independent s-tructu:re al:Lows f'or severa:L advantages. Firs-t:Ly, the dampers may be arranged in such a manner as to be activated 'by gravi-ty, as is -the case i.n a grand p:iano, and not by means of a spring, as is -the case in an llpri.gh-t piano. SecondLy, the keyframe and hammer ac-t:i.on can be al:lowed to slide laterally on the keybed when the sof'-t peda:l. i.s depressed, wi.thollt moving the dampers, -thereby a:l:Lowing for -the act:ion of` a true so~-t pedal.
The acti.on allows the upright piano to pla.y very much as if it were a grand piano, having a -touch simila.r or identica:L to -that ot' a grand piano. The ac-tion is arrangecl in sllch a manner as to fit easil.y int.o the cornpact size and shape of the l~pright piano.
Fea-tures of the inven-tion wil:L be descr:ibed or will become apparent in the course o:f -the fol.:Lowing de-tailed description o:f' the pret'e-rred embodiment of the invent:ion.

BRIE.F DESCXIPTION OF' THE DR~WINGS
The preferred embodiment of.' -the invention will now 'be descri'bed with reference to the accompanying drawings, in which:
Fig. I is a side view of one no-te element o~ the ac-tion, showing it in the unac-tllated position; and Fig. 2 is a view correspondi.ng to Fig. :L, e~ploded -to StlOW the independence of the hammer ac-tion and the damper action.

5~

~ l.ED DES(~R:IPTION Oli` I'H~ PRE~`:ER:RED EMBODIMEN'I`
. ~
'I:'he structure and opera-t.ion QL' the act1on are as follows, described with ref`erence to Fig. :I.
Y'he player depresses the :L'ront of' the liey tnot.
shown)~ which raises -the back of -the key :I, the key be:ing insta.L:Led in the usua.L lever L'ash:i.on on -the key:t'rame 2.
'rhe upwaId movemen-t o-f the back of` the key 1 raises the back check lever 3 via capstan screw ~ causing it to rota-te about its f'l.ange 5, ins-taLled on a backcheck lever raiL 6.
The upward movemen-t o-f'-the back check lever 3 li-fts caps-tan screw 7, causing the whippen assembly to move upT~ardly, ro-tating ill about i-ts flange 8 wh:ich i.s a-ttached to -the whippen :rail 9.
The whippen assembLy is essen-tialLy that of a grand piano, comprising a l~h:ippen arm :L0 p:ivota:Lly connec-ted near :it.s :L'ront end to a flange 8 on whippen rail 9, a repeti-t:ion lever lL p:ivo-tally connected t.o a repetition lever flange 12 protruding upward:Ly .t'rom an in-termediate point of the whippen arm `L0; a jack 13 pivotalLy connected to the wh:ipperl arm l0 nea.r the rear end ot' the whippen arm, the jack 20 comp:r:ising an upward:I,y-directed a-ttack a:rm l'l passing th:rough a slot 15 provided in -the repetit:ion lever :L1 and a rea.rwardly-rli:rected bel].-crank arm 16 .integral wi-th -the attack arm L~L. A repeti-ti.on :Lever spring L7 biases a jack reglllating but-ton 18 on the attack arm 14 :forwardly against 25 a stop :I9 :Eor positi.onin~ the end o:t' the a-ttack arm l~L
di:rectly under the knuckle 20, and at -the same -t:ime `biases t.he repeti.tion lever 1l upwardly against a felt pad on ~ep~-?t~ i t.ion lever screw 2I s~ch -that the repetition Lever II
is prevent,ed lrorn orcIlnariI~ :Iying below -the end ~f the at-tack arm 1.~1 -in the a,re.a o:f` the knIlckLe 20. The stop l~J
and -the repe-tltic>n :I.ever screw 2l a,re both carri.ed on a stop 5 sllpport a:rm 22.
The l~pward movement oi'-t,he whippen assemb.Iy produced by depressing the key :L causes the Jack i.3 -to move upwards so -that its at,t,ack a.rm ,1 'I "at-tacks" the kn~Ick:Le 20 on the ca-tcher arm 23. The attack on -the knuckle 20 causes the lO catcher arm 23 and in-tegra:l hammer shank 2~ to ro-tate abou-t the hamme:r -Flange 25 ins-ta:Lled on main action rail 26, thereby urging -the hammer 27 away from i-ts resting positi.on near the hammer rai:l. 28, -towards the string 30. The hammer 27 is ord-irlari.I.y ass:isted -to its resting posi-tion by a hammer 15 blltt spring 3:L be-tween the hammer shank 2'I and spr:ing :rail 29.
Jus-t before the hammer 27 hits the str:ing 30, -the bell-crank arm 16 of -the jack 13 comes into contac-t with the regulating button 32 a-t,-tached undernea-th main ac-tion rai.:L
20 26. The regul.a-ting but-ton 32 causes the jack 13 to rota-te counter-clockwise (with respect to the viewpoint used in the dra,wings), i.e. so that -the attack arm 14 moves rearwardly (i.e. gene:ra:L:Ly away t'rom the :t'ront of'-the piano and towards the string 30) and away from underneath the knuck:le 20. At 25 essen-tial:l.y the same time, the rearward end of` repeti.tion lever :Ll comes into contac-t with the drop sc:rew 33 installed in hammer :t`lange 25. The drop screw 33 preven-ts any f'urther upward movement o:f -the repeti-tion lever :LI. ThlIs the drop screw 33 and the regulating but-ton 32 controL the compound ~22~5~

eS(`.lpelll~-'llt: 0~' t.he hamrner assemb.l.y t'rom -the repe-t.i-ti,on lever 1:l and attach arm :1 I re.spec-t:ive:ly. When th-is escapement occurs, the hammer 2'i :f'lies t'reely tol^7ards the st.ring 30.
'I'he da,mpi 11~ a( t,ion will now be described. A.s can be seen cleGIrly t'.7o~ F-ig. 2, -t,he damping action i.s independent; Or the hammer ac-tion, and is under direct control. of` the back oi' t,he key l. As t,he key I is depressed, -the ri.s:i,n~ back end of the key :I comes in-to contact with -the dampe:r Lever 3~l, which is pivotal.ly insta:Ll.ed on f`:l.arlge 35 moun-ted on ~ower damper lever rai:l 36. The resul.ting upward ro-tation of the damper lever 3~l Li:fts -the damper wi:re 37 connec-ted to the damper :I:i.f'-ter flange 38, u:L-timate1y causing the upper damper .I.ever 39 to ro-tate abou-t i.ts f'l.ange 40 ins-ta:lled on -the upper damper lever rall. ~1. This ro-tation causes the damper 'i2 -to be lif'ted of:t' the s-tring 30. Lead weights 43 in -the damper :Lever 34 cause -the damper '12 to return -to the string 30 as -the key l starts returning to i-ts res-ting posi-tio:n.
The right pedal li-ft,s al:L of the dampers ~12 from the strings 20 30 by ac-ting to li.f-t -the damper lif-t :rai:L 44 which raises the damper lever 34.
When the hammer 27 s-trihes -the string 30 and rebounds, being -t`ree -to do so by vir-tue of the escapemen-t, the rebounding knuck:Le 20 iands on -the repeti-ti.on lever 11.
25 Since -the downward force ot`-the rebounding hammer is greater -than the orce of'-the repe-ti.-tion l.ever spring 1.7, the knuckle 20 pushes -the repe-t:ition lever ll down, causing i-t to pivo-t about its :t'lange 12. The downward moti.on continues unti1 the mo-tion of the hammer 27 is checked when -the

2~
catcher 1~ t'a1:1s i1~tO the back check ~16, wh:ich :is moved :into poxi tiOIl by vir-tue of the rais-ir1g of the back check leVt?r ~.
As in a g:rand ~ction, -the checki.ng :is qu:Lte secure, whic11 :i.s necessa:ry hecause of' the presence ot' the repeti.-tion l~ver.
'I'he hammer remains in -the checked posi-tion as long as the key l is depressed.
At this poin-t the key 1 is t'ul.Ly depressed, the repetitioll Lever 1:1 :is sl:ight:ly depressed away t'rom repetition lever screw 2] and is e~er-ting upward pressure on the knuck]e 20 by virt~ie o:f the upward -force wh:ich the sprin~q 17 e~erts on -the repeti-tion lever Ll. ~s long as the key remai.ns depressed1 -the llp~ard force of the repetltion lever spring -tr.~ies to push the knuchle 20 up, but canno-t because the hammer :is held in check. However, as soon as the key l is sligh-tly re:Leased and s-tarts to come up, the back check 46 releases the catcher ~}5, and the upward f'orce exerted by the repe-ti-t:i.on lever 1l on the knuck.Le 20 acts to suppor-t the knuck:Le 20 briefly, allowing the attack arm :1'1 of'-the jack 13 to return to its starting position unde:r the 20 knuckle 20 as soon ax it is clear o-f' the regulating button 32. rL'hi.s immediate repositioning of'-the a-ttack arm l/1 of the ~jack l3 allows for immediate and continued repetition of the note if' desired, withou-t need f'or the key :1 to be fu:Lly released.
When the soft pedal (not shown) i.s depressed, -the keyf':rame 2 and hammer action, including the backcheck :Lever rail 6, -the whippen rai:L 9, main action rail 26, and spring rai:L 29, slide lateral:l.y on t.he keybed (not shown). If the key l is depressed whi.le the soft pedal. is depressed, the 122~9SO
h.lmmer 2'7 t,hllCI strikes -f`e~er str-irl~s than usllFll, -thereby producing a so~'-te~ sollnd.
rl'his is possible bec~use as in a ~and pi,ano, the damper action is comple-tely independen-t of -the hamrner act:ion (as shown clearLy in ~'ig.2), ~o t,ha-t -the key-~'rame and t,he hammer action can be IllO~f? I.a-terally withou-t af'f'ec-ting -the damping mechanism.

Claims (3)

THE EMBODIMENTS OF THE INVENTION IN WHICH AN EXCLUSIVE
PROPERTY OR PRIVILEGE IS CLAIMED ARE DEFINED AS FOLLOWS;

1. In an upright piano action in which each note element of the action comprises a substantially horizontal key in the form of a lever pivotally connected to a frame member of the piano such that the back of the key is raised when the front playing portion of the key is depressed, a back check lever pivotally connected to a frame member and positioned above the back of said key to be raised by upward movement of the back of the key, at least one substantially vertically-oriented piano string installed on a frame member, a hammer-carrying shank pivotally installed on a main action rail about a horizontal axis for moving said hammer towards and away from said at least one piano string, and actuating means arranged between said back check lever and said hammer shank for actuating said hammer in response to the upward movement of said back check lever, the improvement in which said actuating means for each note element comprises:
a catcher arm integrally connected with said hammer shank at a substantial angle such that substantially upward movement of said catcher arm produces essentially rearward movement of said hammer towards said piano string, said catcher arm including a knuckle on its lower surface and further including a catcher at its forward end for engagement with a back check provided on said back check lever when said key has been fully depressed and said hammer has rebounded from said piano string;
a grand whippen disposed above said back check lever, said grand whippen comprising: a whippen arm pivotally connected near its front end to a whippen rail; a repetition lever pivotally connected to a pivot support arm protruding upwardly from an intermediate point of said whippen arm; a jack pivotally connected to said whippen arm near the rear end of said whippen arm, said jack comprising an upwardly-directed attack arm passing through a slot provided in said repetition lever and a rearwardly-directed bell-crank arm integral with said attack arm; and spring means for biasing said attack arm of said jack forwardly against a stop for positioning directly under said knuckle and for biasing said repetition lever upwardly and against a stop such that said repetition lever does not ordinarily lie below the end of said attack arm in the area of the knuckle, said stops being attached above said whippen arm;
a regulating button positioned below said main action rail and positioned above said bell-crank arm of said jack for engaging said bell-crank arm just prior to said hammer contacting said piano string; and a drop screw fixed with respect to said main action rail and positioned for engaging said repetition lever just prior to said hammer contacting said piano string.

2. An upright piano action improvement as recited in claim 1, in which said actuating means for each note element is installed on a keyframe of the piano capable of lateral movement with respect to said piano strings.

3. An upright piano action improvement as recited in claim 2, further comprising damping means including a damper lever pivotally connected to a damper lever rail and positioned above the back of said key to he contacted by the rising back of said key then said key is depressed, a damper wire 37 connected to said damper lever to be raised when said damper lever is raised, a damper ordinarily resting on said piano strings, an upper damper lever pivotally installed on an upper damper lever rail connecting said damper wire and said damper for converting said upward movement of said damper wire into movement of said damper forward and away from said strings, said damping means being structurally independent from said actuating means whereby said actuating means may move laterally without said damping means being moved laterally.