Abstract:
A damper action for an upright piano that comprises a springed tab on the damper lever that “ratchets” or gives way or folds away in one direction and does not in the other, to provide retention when the spring tab passes by the longitudinal ridge on the sostenuto rod in one direction and non-retention when the spring tab passes by the longitudinal ridge on the sostenuto rod the other direction. The ratchet aspect of the spring tab uses tension from the damper spring and does not require a separate spring to apply tension to yield the ratchet effect.

Description:
BACKGROUND OF THE INVENTION 
     1. Field of the Invention 
     This invention relates to the damper actions of upright pianos. A damper action is a mechanism that transmits motion from a piano key and/or motion from a piano pedal into motion of a damper resting on a piano string located inside the piano. In every piano, there is one damper action per piano key, where there are typically 88 piano keys in a piano. When a piano key is at rest, the corresponding damper of the corresponding damper action rests on or presses down onto the corresponding piano string(s), thereby preventing the string(s) from vibrating or making sound. When the piano key is depressed, the damper action causes the damper to lift off of the piano string(s), thereby allowing the string(s) to vibrate and to make sound. When the piano key is released, the damper action causes the damper to return to the rest position, pressing back onto the piano sting(s), thereby dampening the vibrations and eliminating the sound of the piano string(s). Alternately, damper actions may be actuated to lift dampers by depressing the sustain pedal or by depressing the sostenuto pedal of the piano. When the sustain pedal or the sostenuto pedal is depressed, one or more dampers is lifted from the piano strings to allow the strings to vibrate without dampening. When the sustain pedal or the sostenuto pedal is released, the damper is returned to the rest position to press down onto the piano strings dampening the sound therefrom. This invention specifically relates to one subcomponent of a damper action, namely the sostenuto tab or sostenuto lip located on the damper lever. 
     2. Description of Related Art 
     A damper action comprises: a damper lever, a damper spring, a damper wire, and a damper. A damper action cycles with a key depression, a sustain pedal depression, or a sostenuto pedal depression, where each causes the damper lever to rotate, to move the damper wire attached to one end of the damper lever, which rotates the damper attached to the other end of the damper wire. This causes the damper to be lifted away from the piano strings to allow vibrations and sounds to sustain on the piano strings without dampening by the damper. When the key, sustain pedal, or sostenuto pedal is released, the damper lever returns to the rest position thereby returning the damper to press back against the piano strings. The damper spring puts tension on the damper lever to cause the damper to press against the piano strings when the damper action is at rest. Thus, the damper spring causes the damper to return to the rest position on the piano strings when the piano key is released. 
     There are three possible ways to actuate a damper action: key depression, sustain pedal depression, and sostenuto pedal depression. 
     When a piano key is depressed, this causes rotation of the corresponding damper lever, which removes the correspond damper from the corresponding piano strings. When the key is released, the damper lever cycles back to cause the damper to rest back on the piano strings. Thus, one key depression actuates one damper action. 
     When the sustain pedal is depressed, this causes a sustain lifter rod to rotate, which causes all 88 damper levers in the piano to rotate, thereby removing all 88 dampers from the piano strings. Thus, one sustain pedal depression actuates all 88 damper actions. 
     When the sostenuto pedal is depressed, this causes all damper actions already actuated from key depression at the time the sostenuto pedal was depressed, to remain detached from the piano strings, even after the formerly depressed keys are released, as long as the sostenuto pedal is held depressed. Depressing the sostenuto pedal allows piano stings to continue to make sound after the corresponding keys are released and to continue to do so until the sostenuto pedal is released. Thus, the sostenuto pedal suspends the return of certain dampers until the sostenuto pedal is released. When the sostenuto pedal is released, the respective dampers return to press back against the piano strings and to dampen the sound produced therefrom. 
     As discussed in detail below, when the sostenuto pedal is depressed, this causes a sostenuto rod to rotate. When the sostenuto rod rotates, a longitudinal ridge on the sostenuto rod aligns with a tab on the damper levers, to prevent the damper levers from rotating back to the rest position after the key is released. 
     A problem arises at this point regarding the ability to play other piano keys while holding the sostenuto pedal in the depressed position. As discussed in detail below, depressing a key and actuating a damper action while the sostenuto pedal is depressed causes the tab on the corresponding damper lever to interfere with the longitudinal ridge on the sostenuto rod to produce a clicking sound from the two parts contacting each other, or, even worse, to disrupt the tone of the strings from erratic damper movement caused by the two parts colliding with each other. Thus, there is a problem playing other piano keys while holding the sostenuto pedal down. 
     The same problem arises when the sostenuto pedal is released. If a key is depresses just as the sostenuto pedal is released, this also causes the tab on the corresponding damper lever to interfere with the longitudinal ridge on the sostenuto rod to produce a clicking sound from the two parts contacting each other, or, even worse, to disrupt the tone of the strings with erratic damper movement caused by the two parts colliding with each other. Similarly, when the sostenuto pedal is released while holding down later depressed keys, the longitudinal ridge on the sostenuto rod interferes with the tab on the corresponding damper lever to produce a clicking sound from the two parts contacting each other or even worse to disrupt the tone of the strings from erratic damper movement caused by the two parts colliding with each other. Thus, there is a problem releasing the sostenuto pedal while play or holding other piano keys. 
     To remedy these problems, this invention provides a spring tab on the damper lever that “ratchets” or gives way or folds away in one direction and does not in the other, to provide retention when the spring tab passes by the longitudinal ridge on the sostenuto rod in one direction and non-retention when the spring tab passes by the longitudinal ridge on the sostenuto rod the other direction. Further, as discussed below, the ratchet aspect of the spring tab uses tension from the damper spring and does not require a separate spring to apply tension to yield the ratchet effect. 
     There are no upright piano damper actions in the prior art with spring tabs on the damper levers. There are no upright piano damper actions in the prior art with ratcheted tabs on the damper levers that hold tension from the existing damper spring of the damper action. 
     BRIEF SUMMARY OF THE INVENTION 
     It is an aspect of this invention to provide a damper action for an upright piano that allows the playing of piano notes by striking piano keys after the sostenuto pedal has been depressed and before it is released, without causing a clicking sound or other unwanted sound originating from any contact between the longitudinal ridge on the sostenuto rod and the tab on the damper levers corresponding to stricken keys. 
     It is an aspect of this invention to provide a damper action for an upright piano that allows the playing of piano notes by striking piano keys after the sostenuto pedal has been depressed and before it is released, without causing a change or disruption in piano tone or sound originating from any contact between the longitudinal ridge on the sostenuto rod and the tab on the damper levers corresponding to stricken keys. 
     It is an aspect of this invention to provide a damper action for an upright piano that allows the playing of piano notes by striking piano keys at the same time that the sostenuto pedal is released without causing a clicking sound or other unwanted sound originating from any contact between the longitudinal ridge on the sostenuto rod and the tab on the damper levers corresponding to stricken keys. 
     It is an aspect of this invention to provide a damper action for an upright piano that allows the playing of piano notes by striking piano keys at the same time that the sostenuto pedal is released without causing a change or disruption in piano tone or sound originating from any contact between the longitudinal ridge on the sostenuto rod and the tab on the damper levers corresponding to stricken keys. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  is a side elevation view of a piano key, a piano action, a damper action, and a piano string of an upright piano with sostenuto spring tab, with piano key at rest. 
         FIG. 2  is a prospective view of a piano key, a piano action, a damper action, and a piano string of an upright piano with sostenuto spring tab with piano key at rest. 
         FIG. 3  is a snapshot of  FIG. 1  with piano key fully depressed. 
         FIG. 4  is a snapshot of  FIG. 1  with sustain pedal fully depressed. 
         FIG. 5  is a side elevation view of a piano key, a piano action, a damper action, and a piano string of an upright piano of the Prior Art without sostenuto spring tab, with piano key at rest. 
         FIG. 6  is a snapshot of  FIG. 5  with piano key fully depressed. 
         FIG. 7  is a snapshot of  FIG. 6  with sostenuto pedal fully depressed. 
         FIG. 8  is a snapshot of  FIG. 7  with piano key released and sostenuto pedal fully depressed. 
         FIG. 9  is a side elevation view of different piano key, piano action, damper action, and piano string of the same piano as  FIG. 8 , with its key fully depressed after holding down the sostenuto pedal where the interference between longitudinal ridge and damper lever tabs can be noted. 
         FIG. 10  is a side elevation view of a piano key, a piano action, a piano string, and a damper action with sostenuto spring tab of an upright piano, with piano key at rest. 
         FIG. 11  is a snapshot of  FIG. 10  with piano key fully depressed. 
         FIG. 12  is a snapshot of  FIG. 11  with sostenuto pedal fully depressed. 
         FIG. 13  is a snap shot of  FIG. 12  with piano key released and sostenuto pedal fully depressed. 
         FIG. 14  is a side elevation view of different piano key, piano action, damper action, and piano string of the same piano as  FIG. 13 , with its key fully depressed after holding down the sostenuto pedal, where the lack of interference between longitudinal ridge and the sostenuto spring tabs can be noted due to the ratchet effect of the sostenuto spring tabs. 
         FIG. 15  is a blow-up view of a damper action for an upright piano with sostenuto spring tab. 
     
    
    
     DEFINITION LIST 
     
       
         
               
               
             
               
               
             
           
               
                   
               
               
                 Term 
                 Definition 
               
               
                   
               
             
             
               
                   
               
             
          
           
               
                 1 
                 Piano Key 
               
               
                 2 
                 Balance Point of Piano Key 
               
               
                 3 
                 Dowel Capstan 
               
               
                 4 
                 Whippen 
               
               
                 5 
                 Damper Spoon 
               
               
                 6 
                 Jack 
               
               
                 7 
                 Hammer Butt 
               
               
                 8 
                 Hammer 
               
               
                 9 
                 Damper 
               
               
                 10 
                 Piano String 
               
               
                 11 
                 Sostenuto Rod 
               
               
                 12 
                 Sostenuto Spring Tab 
               
               
                 13 
                 Damper Lever 
               
               
                 14 
                 Sustain Lifter Rod 
               
               
                 15 
                 Rigid Sostenuto Tab (Prior Art) 
               
               
                 16 
                 Damper Flange 
               
               
                 17 
                 Damper Spring 
               
               
                 18 
                 Sostenuto Spring Tab Center of Rotation 
               
               
                 19 
                 Engagement Tip of Sostenuto Spring Tab 
               
               
                 20 
                 Sostenuto Bracket 
               
               
                   
               
             
          
         
       
     
     DETAILED DESCRIPTION OF THE INVENTION 
     An upright piano damper action comprises: a damper lever  13 , a damper spring  17 , a damper wire (depicted, not numbered), and a damper  9 . A damper action cycles with a key  1  depression, a sustain pedal (not depicted) depression, or a sostenuto pedal (not depicted) depression, where each causes the damper lever  13  to rotate. Damper lever  13  is a rigid oblong member with two ends. Damper lever  13  rotation occurs about center-of-rotation point  18  which is located near the center of damper lever  13 . When a damper action is at rest, damper  9  rests against or presses against piano string  10  to dampen any vibrations or sounds in the piano string. Thus, when at rest, a damper action dampens the piano string. When a key, sustain pedal, or sostenuto pedal is depressed, the upper end of damper lever  13  rotates away from piano string  10  to become detached therefrom thereby removing any vibration or sound dampening effects on the piano string  10 . When a key, sustain pedal, or sostenuto pedal is released, the upper end of damper lever  13  rotates back towards piano string  10  to rest or push slightly there against thereby reestablishing the vibration or sound dampening effects on the piano string  10 . 
     Damper spring  17  puts tension on damper lever  13  to cause damper  9  to press against piano string  10  when the damper action is at rest. Thus, damper spring  17  causes damper  9  to return to the rest position on the piano strings when the piano key, the sustain pedal, and/or the sostenuto pedal is released. Damper spring  17  is a spring that exerts tension on the upper end of damper lever  13 . Damper spring  17  presses on one end against damper flange  16  which is connected to a rigid piano rail and thus this end of damper spring  17  remains stationary and fixed in location. The other end of damper spring  17  exerts tension against the upper end of damper lever  13 . Since damper lever  13  is a rotating member, it is pushed by spring tension against piano string  10 . 
     In  FIGS. 1 and 2 , piano key  10  is at rest. In this condition, damper spring  17  pushes damper  9  in a counterclockwise direction against piano string  10 . 
       FIG. 3  depicts how a piano key actuates the damper action. The depression of piano key  1  causes the piano action to cycle, which causes the damper spoon  5  to rotate in a counterclockwise direction, to contact the lower end of damper lever  13 , thereby causing damper lever  13  to rotate in a clockwise direction, thereby removing damper  9  from pressing against piano string  10 . During this motion, the piano action also caused hammer  8  to strike piano string  10  to instill vibrations and sound going un-dampened because the damper is removed from the string. String  10  remains un-dampened at this point until the piano key  1  is released. 
       FIG. 4  depicts how the sustain pedal actuates the damper action. The depression of the sustain pedal causes sustain lifter rod  14  to rotate in a counterclockwise direction and to move towards piano string  10 , which causes sustain lifter rod to contact the lower end of damper lever  13 . This motion causes damper lever  13  to rotate in the clockwise direction in  FIG. 4 . Sustain lifter rod  14  is a long rod, rail, or track positioned parallel to the piano keyboard running the full width of the piano. When lifter rod  14  rotates and moves, it pushes on all 88 damper levers  13  in order to remove all dampers  9  from all piano stings  1  in the piano. When the sustain pedal is released, sustain lifter rod  14  rotates back in a clockwise direction and moves way from the lower ends of damper levers  14 , thereby allowing tension from all damper springs  17  to push all dampers  9  back against piano strings  1 . 
       FIGS. 5-9  depict how the sostenuto pedal actuates one or more damper actions with prior art upright piano damper actions.  FIG. 5  depicts piano key  1  at rest with damper action at rest.  FIG. 6  depicts piano key  1  fully depressed, so that damper spoon  5  contacts the lower end of damper lever  13  to rotate this member in the clockwise direction, to lift damper  9  from piano string  10 . In this state, lush sustaining sound may be achieved without sound dampening from the damper action. Dampening reverts however to return the damper as according to  FIG. 5  upon the release of depressed piano key  1 . 
     Before the returning to the  FIG. 5  dampened state, however, the pianist may wish to sustain these already depressed notes and then move on to playing other notes without such sustain.  FIGS. 7-9  depict this state of affairs. 
       FIG. 7  depicts the rotation of sostenuto rod  11  in response to depression of the sostenuto pedal. The depression of the sustain pedal causes sostenuto rod  11  to rotate in a counterclockwise direction. The longitudinal axis of sostenuto rod  11  runs perpendicular to the pages of all figures except  FIG. 2 . Sostenuto lifter rod  11  is a long rod, rail, or track positioned parallel to the piano keyboard running the full width of the piano. Sostenuto rod  11  comprises a longitudinal ridge on the exterior running along the length of the rod. Longitudinal ridge rotates when sostenuto rod  11  rotates. When sostenuto pedal is at rest, longitudinal ridge is positioned as depicted in FIGS.  5 - 6 , at the nine o&#39;clock location. When sostenuto pedal is fully depressed, longitudinal ridge is positioned as depicted in  FIGS. 7-9 , at the six o&#39;clock location. As depicted, longitudinal ridge rotates about a quarter turn in response to sostenuto pedal depression. 
     In  FIG. 8 , piano key  1  has been released while holding the sostenuto pedal depressed. This cases damper spoon  5  to move in the rightward direction, thereby releasing pressure on the lower end of damper lever  13 , causing damper spring  17  to exert pressure on the upper end of damper lever  13  in the counterclockwise direction. Normally this would return damper  9  to rest upon piano string  10 . However, damper  9  does not return to rest upon piano string  10  because of the pressure exerted on the sostenuto pedal, translating to pressure on rigid tabs  15 . Damper  9  would return but for rigid tab  15  snared against the longitudinal ridge of sostenuto rod  11 . Thus, the sostenuto pedal actuates the damper action to hold damper  9  away from piano string  10  until the pedal is released. 
     The nature of the problem with the prior art is depicted in  FIG. 9 . While the sostenuto pedal is depressed and thus while longitudinal ridge is at the six o&#39;clock position, when new piano keys  1  or new piano notes are played, the piano action still actuates the damper action. Thus, damper spoon  5  moves leftward to contact the lower end of damper lever  13 , to rotate the member, causing rigid tab  15  to crash into the longitudinal ridge of sostenuto rod. This collision is a problem for most pianists. 
       FIGS. 10-15  depict how this collision does not occur using sostenuto spring tab  12  using tension from the damper spring  17 .  FIG. 10  depicts piano key  1  at rest with damper action at rest.  FIG. 11  depicts piano key  1  fully depressed, so that damper spoon  5  contacts the lower end of damper lever  13  to rotate this member in the clockwise direction, to lift damper  9  from piano string  10 . In this state, lush sustaining sound may be achieved without sound dampening from the damper action. Dampening reverts however to return the damper as according to  FIG. 10  upon the release of depressed piano key  1 . 
     Before the returning to the  FIG. 10  dampened state, however, the pianist may wish to sustain these already depressed notes and then move on to playing other notes without such sustain.  FIGS. 12-14  depict this state of affairs. 
       FIG. 12  depicts the rotation of sostenuto rod  11  in response to depression of the sostenuto pedal. The depression of the sustain pedal causes sostenuto rod  11  to rotate in a counterclockwise direction. The longitudinal axis of sostenuto rod  11  runs perpendicular to the pages of all figures except  FIG. 2 . Sostenuto lifter rod  11  is a long rod, rail, or track positioned parallel to the piano keyboard running the full width of the piano. Sostenuto rod  11  comprises a longitudinal ridge on the exterior running along the length of the rod. Longitudinal ridge rotates when sostenuto rod  11  rotates. When sostenuto pedal is at rest, longitudinal ridge is positioned as depicted in  FIGS. 10-11 , and  15 , at the nine o&#39;clock location. When sostenuto pedal is fully depressed, longitudinal ridge is positioned as depicted in  FIGS. 12-14 , at the six o&#39;clock location. As depicted, longitudinal ridge rotates about a quarter turn in response to sostenuto pedal depression. 
     In  FIG. 13 , piano key  1  has been released while holding the sostenuto pedal depressed. This cases damper spoon  5  to move in the rightward direction, thereby releasing pressure on the lower end of damper lever  13 , causing damper spring  17  to exert pressure on the upper end of damper lever  13  in the counterclockwise direction. Normally this would return damper  9  to rest upon piano string  10 . However, damper  9  does not return to rest upon piano string  10  because of the pressure exerted on the sostenuto pedal, translating to pressure on sostenuto spring tab  12 . Damper  9  would return but for sostenuto spring tab  12  snared against the longitudinal ridge of sostenuto rod  11 . Thus, the sostenuto pedal actuates the damper action to hold damper  9  away from piano string  10  until the pedal is released. 
     Referencing  FIG. 14 , while the sostenuto pedal is depressed and longitudinal ridge is at the six o&#39;clock position, when new piano keys  1  or new piano notes are played, the piano action still actuates the damper action. Thus, damper spoon  5  moves leftward to contact the lower end of damper lever  13 , to rotate the member, causing rigid tab  15  to threaten a collision with these members. However, with the design of the sostenuto spring tab  12 , tab  12  breaks away to rotate in the counterclockwise direction, thereby avoiding the collision. Spring tab  12  is merely pushed aside rather than crashed into. This eliminates all unwanted sounds created with upright pianos of the prior art. 
     Referencing  FIG. 15 , spring tab  12  is a rocker member with center of rotation at point  18 . Spring tab  12  is a cylindrical member with a longitudinal ridge running down two opposite sides of the member. One longitudinal ridge is used to catch onto the longitudinal ridge of the sostenuto rod  11 . The other is used to catch on a ridge of the damper lever  13  to prevent rotation in the clockwise direction. Center-of-rotation  18  runs along the center axis of the member. Spring tab  12  is positioned on the upper end of damper lever  13  in such a way as to limit spring tab  12  rotation in the clockwise direction but allow slight rotation in the counterclockwise direction. This is accomplished by spring tab  12  meeting resistance from the damper lever  13  in one direction but not so in the other. 
     Still referencing  FIG. 15 , damper spring  17  is semirigid oblong spring member as depicted that holds damper lever  13  firmly against piano string  10 . Damper spring  17  also holds spring tab  12  firmly in the clockwise direction against the damper lever  13  by pressing on the exterior of one of its longitudinal ridges. Spring tab  17  is a low tension spring so that the pressure required to depress a piano key  1  should easily overtake that required to bend spring. 
     Because of the ratcheted or one-way break away design of the sostenuto spring tab  12 , the longitudinal ridge of sostenuto rod can hold tight onto sostenuto spring tab  12  in the clockwise direction but allow the spring tab  12  to freely pass in the counterclockwise direction.