Action (piano)

As a piano action, hammer action or striking mechanism is called a lever construction, are hurled at the touch of a button hammers against the strings of a piano to get this to blades.

• 3.1 Under damper
• 3.2 overdampers

History

One of the forerunners of the piano action are the mechanics of the harpsichord in the strings using quills are plucked and the mechanics of the clavichord, are struck by tangents at the strings. For the development of a mechanism, are struck by hammers on the strings, also was the model of the hammered dulcimer of importance, whose strings a player strikes with guided in hands mallets.

As in 1700, a dulcimer virtuoso named Pantaleon Hebenstreit ( 1668-1750 ) toured Europe and gave acclaimed concerts, various instrument makers set out to mechanize the game of dulcimer through a keyboard.

One of these men was the Florentine Bartolomeo Cristofori, who produced in 1710 the first copies of a jack mechanism. Regardless invented the Frenchman Marius J. ( 1716) and Nordhäuser Christoph Gottlieb Schröter ( 1717) a keyboard instrument whose strings are not plucked but struck by hammers. Important for the further development of the pianoforte were especially Gottfried Silbermann (1683-1753) in Strasbourg and Johann Andreas Stein in Augsburg, considered the spiritual father of the Viennese action.

Other markers in the development of the piano action was the construction of an overshot mechanics by Nannette Streicher and Theodor Stöcker and the invention of a Repetitionsmechanik ( "double échappement " ) by Sébastien Erard in 1823.

One of the latest innovations in the history of the piano action constitutes a patent of the Bamberg piano maker Josef My host, who presented a Knuckle Rollers in 2002.

Mechanics types of wings and the way they operate

For the variety of different types of mechanics, which was developed over the last two and a half centuries, created almost as many names. This mechanism types have been baptized not only according to its functioning or its inventor, but also according to their origin or the place of its largest circulation, which can lead to some confusion. In addition, a distinction is required by mechanics for vertically strung upright pianos and mechanisms for horizontally strung wing and square pianos.

Tangent mechanics

An early form of the mechanics in the transition from the clavichord and harpsichord to fortepiano was the tangent mechanics. When you have no hammer is thrown against the string, but a wooden box, called " tangent ".

By pressing the button (A) to its rear end lifts with the Pilote (B). The capstan pushes the driver ( C) up, which in turn throws the legislation at a rake tangent ( D) against the string (E). At the same time, the damper (B ) rises, so that the string can vibrate freely.

Single Action

An early shock mechanism, which can be found in the English panel pianos is called " Single Action ", which translates as " easy trigger " means. In her flat Hammerleistchen are secured with semi-circular leather-covered hammers by a leather tongue hinge in a separate hammer chair. A pestle made ​​of brass wire with a leather-covered wooden doll serves as a trigger. By pressing the button (A) hurls the pestle (B) the hammer rail (C ) against the string (D). Simultaneously, the rear end of key raises the damper ( E) of the string, so that it can swing freely.

Double Action

1776 Georg Fröschle built in London for the first time a square piano - shock mechanism with driver. Ten years later, settled John Geib patented this mechanism type as " Double Action ", and up to 1800 only instruments of the company Longman & Broderip were allowed to be equipped with it. It has in comparison with the " Single Action " about an additional driver. The game technical advantage in a nuanced richer stop and a more familiar game. By pressing the button (A) pushes the trigger ( B) against the driver ( C). This in turn throws the hammer (D ) up against the string (E). At the same time stands out over a mechanism at the key end of the damper (F) of the string, so that it can swing freely.

Viennese action

Piano tuners after the bounce principle received early the name " German mechanics" or " Viennese action " because they were built primarily by German and Austrian piano maker. By applying pressure to the front end (right in picture) button (A ), the rear end lifts (left in the picture) with the capsule ( B) and the therein Hammer ( C). The rear (left ) end of the hammer, called " beak" (D), bounces against the bar (E), so that the front end with the hammer head (F) against the string (G ) fast. At the same time, the damper (H ) leaves the string, so that it can swing freely. After the attack, the beak slips past the bar, so that the hammer head can fall back on the hammer rest cushion ( I).

Prell tongue mechanism with single trigger

Since a rigid, common to all the hammers bounce - bar, a fine adjustment of the tripping is problematic, the bounce - bar was soon replaced by single movable bounce tongues. These tongues are fastened to a bumper leather hinge and held by a spring on the end of the hammer shank. The adjustable bias of the spring and the moment of the energy of the trigger can now be changed.

By applying pressure to the front end (right in picture) button (A ) to its rear end lifts (left in the picture) with the capsule located on it (B) is suspended in at an axis of the hammer ( C). Its rear end, called " beak" (D), becomes entangled in the paragraph a resiliently mounted bounce tongue (E ) (also "triggers" ) so that the front end lifts and the hammer head (F ) upwards hurls against the string. Simultaneously, the puppet damper (G) is moved upward and lifts the overlying absorber ( H) of the string. After the attack, the hammer head fall back into the trap ( I). At the decline of the button the beak leather slides on the tongue along bounce back to its original position.

Oberschlägige mechanics

The oberschlägige mechanics is in the architectural history of the piano is a special case, which was first tested by the Viennese piano maker and Andreas Streicher Nannette Streicher, and later by the London piano makers Robert Wornum and the Berlin piano maker Theodor Stöcker. When you meet the hammers from above the horizontal strings. The advantage is that the strings are struck by the hammers in the direction of the bridge and the soundboard and not away from them, so that a higher efficiency between effort and sound outcome results. The disadvantage, however, is that the hammers can not fall back by gravity to its rest position, but must be retrieved using a spring mechanism. In addition, due to a oberschlägige mechanics, so that the process of tuning is complicated a more complicated arrangement of the tuning peg.

The pressure on the front end (right in picture) button (A ) is the bridge ( B) on the pestle (C ) transfer that pushes the butt (D ) down, so that the hammer head ( E) against the string ( F) impinges. At the same time an onboard rear end of the key rod pushes the damper ( G) of the string, so that it can swing freely. After the attack the spring ( H) takes out the hammer back to the top. When released, the spring (I) them. Again back to top to its original position

Jack mechanism

By spreading the jack mechanism by English piano maker mechanics types received after the jacks principle also the name "English mechanics". Further modifications were also " half- English mechanics " and "Full English mechanics" called, although these were developed by German and Austrian piano builders, such as the " Blüthner Patent mechanics". " Half English mechanics " there was to about 1900.

By applying pressure to the front end (right in picture) button (A ) to its rear end lifts (left in the picture) with the jack located on it (B). This pushes against the butt (C ) of a chair in the hammer (D ) having an axis suspended hammer and thus hurls the hammer head (E ) upwards against the string. After the attack, the hammer will fall back into the trap ( F).

Repetitionsmechanik ( "double échappement " )

The Repetitionsmechanik of Sébastien Erard from 1821 is an advanced jack mechanism which allows rapid repetition ( = repeatedly striking ) of tones. It represents the current state in the development of the piano action

By applying pressure to the front end of the button (A) to its rear end lifts with the capstan located on it (B). The capstan pushes the lift link unit (C) upward, so that the movable therein mounted jack (D) abuts the shank roller ( E) and the hammer head (F ) up flings. However, before he touches the string, meets the trigger arm (G) on the regulating button (H ), so that the jack (D) is moved out of its position under the hammer shaft pulley ( E). Previously, the repetition lever ( J) has been isolated by the Abnickschraube fixed in the newer mechanisms of the hammer from the hammer capsule - hence the term " Repetitionsmechanik double trigger ". Thus, the direct power transmission between the key and hammer is broken, so that the hammer head alone by the transmitted pulse at him the rest of the way to the string overcomes while the key reaches its bottom dead center. After the attack, the hammer head bounces back and is in the catcher ( I) stopped halfway. Here, the repetition lever (J) is pressed downwards and increases the tension to the repetition spring (K). Once the catcher releases the hammer head, the repetition lever lifts the hammer shank (L ) so far that the jack can return (D) in their attack position under the hammer shaft pulley ( E). Thus, the lever system is ready for a renewed attack, even before the (A) button is again completely returned to its upper rest position.

Mechanics types of upright pianos ( pianos ) and their modes of

When pianino the upward movement of the rocker switch to a forward movement of the hammer must be implemented. Thus, the contact with the hammer is somewhat indirect. This reaction is generally achieved by a jack under the so-called " butt " grips, the rotary joint for the hammer. The movement of the hammer is " coupled " to the nut, the jack caused deflected sideways before the movement of the hammer reaching the strings. As with the wing must also be prevented when upright piano that by hammer and finger force, the strings are firmly pressed - the mount point of the hammer is only achieved with the momentum in free flight. The technical term for this is the " trigger ".

In pianos is usually the set of strings of a note, the " choir", quite far struck above. As the wing is provided with about one-seventh to ninth of the freely vibrating string length for almost all cases an ideal tone of the hammer impact point. At very high concert pianos (over about 135 length) are specially selected rod-shaped extensions of key operations, so-called abstract, required.

In contrast, there was in the 1950s to the 1970s spinets (so-called " spinets " in English ), which are built so low that an attack of the hammers on the keys is not possible and is done transmitting the key lever down. These miniature pianos are sonically disadvantage and to repair because of the offset operation more difficult and expensive to maintain, and also to vote.

Under damper

The attenuation of an upright piano or high piano is usually located below the hammers on the same side of the strings conditioning, in the area of ​​stronger amplitude of the antinodes.

Overdampers

However, older upright pianos have ( until about 1910), partly a so-called upper damper mechanism; the damper dolls sit on the hammers. In English, you will find this and the term " birdcage action", " bird cage " mechanism, because of the built in front of the hammer action damper actuator wires. This type of damping is to a less effective than that of a sub- damper piano as it dampens the oscillations only in the edge region of the anti-nodes, the Moreover, the damping doll prevent optimal hammer stopper point with short trebles - with corresponding disadvantages of sound quality, and can be used to further the voices, and especially the mechanism of regulating be difficult. That overdampers pianos in general, however, are completely useless, as you can often claimed, one can not say. A well regulated overdampers piano is because of its significant Nachklingens the predestined instrument for early jazz and especially for the ragtime.