US2424017A - Piano-action - Google Patents

Description

A. P. BROWN July 15, 1947.

PIANO-ACTION Filed Dec. 22, 1945 INVENTOR. ALEXANDER R BROWN BYM ATTORNEY Patented July 15, 1947 UNITED STATES PATENT OFFICE PIANO-ACTION Alexander P. Brown, Beechhurst, N. Y.

Application December 22, 1945, Serial No. 636,656

8 Claims. 1

My invention relates to piano actions and, more particularly, to actions for splnets of restricted dimensions. An object of my invention is to provide an action which can be inserted in a piano of a height not much exceeding the height of the keys.

In the prior art, this object has been attained by providing mechanisms connecting the key with an actuating element positioned at a lower level whereby the height of an action of otherwise more or less conventional structure is reduced. Such devices are known as underslung actions. They have several severe disadvantages. The mechanism interposed between the key and the proper action increases the number of parts required, requires higher expenses, makes the structure more complicated, makes the proper adjustment more difficult and less reliable and results in a mushy touch and tones of poor quality.

Further objects of my invention are to avoid these drawbacks, to actuate the proper action by direct blow or stroke of the key, and, thereby, to obtain tones of perfect quality.

Other objects are to provide a jack with a lower end positioned considerably below the level of the key; to provide a hammer with a pivoted butt positioned at its lower end; to provide for a hooking engagement between the jack and the hammer butt whereby the jack releasably engages the hammer and swings the same from the position of rest'toward the sound string, can be disengaged from the hammer when the latter rebounds, and swings the hammer back from the rebounded position into the position of rest; to provide a wippen having an arm struck upward by the key and having another arm moving down at the same time and carrying a back check; to provide a jack hinged to this latter arm and moving down when the key is struck; and to arrange these parts in a narrow space located at the back side of the key.

Further objects are to provide a damper with a hinge positioned near its lower end and considerably below the level of the key, and to provide this damper with an extension which is engaged by the jack at the end of a stroke.

Still other objects are to arrange the hammer and the jack at a short horizontal distance from each other; to facilitate, thereby, the hooked cooperation of these parts; to provide, thereby, for a small horizontal'measure of the action and of the piano; and to provide a structure of the hammer rest which can be positioned in the narrow space between the hammer and the jack.

Still further objects are to provide a fixed stop for the jack whereby the same is turned around its hinge at the end of a stroke; to provide the jack with a projection engaging a recess of the hammer butt and disengaged from this recess by this turning movement; and to provide means urging the jack into the engaging position.

Still other objects are to provide the hammer butt with a fixed pivot positioned in front of the engaging projection of the jack; and to provide this butt with a recess positioned between this pivot and this jack projection.

Still further objects are to reduce the number of parts, to simplify the structure of a piano action of this type, and to make it unnecessary to provide the hammer with a spring.

Still other objects and advantages will appear from the following description of an exemplifying embodiment of my invention, from the appended claims and from the accompanying drawing in which the figure shows a vertical, partially sectional side view of this embodiment.

It should be noted that, throughout this specification and claims, the front side" is understood to be the side facing the performer or the left side in the drawing, and the back side to be the side facing the sound string or the right side in the drawing.

Referring to the drawing, numeral l indicates a key of conventional structure shown broken off, the front part of this key being omitted. Preferably, the back end of the key is reduced in height.

The key I can be operated either by the hand of a performer or by a pneumatic action which may move a wire 2 in vertical direction. The wire 2 may pass slidably through an opening of a block 3 aflixed, by a screw 46, to the key bed 4 and may have an upper end provided with a head 5 contacting a padded lower surface of the key I. In both kinds of operation, the back end of the key I moves upward when the key is struck.

A wippen 6 has a fixed pivot 1 positioned, in horizontal direction, beyond the key I. The pivot 1 connects the wippen 6 rotatably to a part 41 which is afiixed, by a screw 48, to a bar 49 forming a part of the pianos stationary structure. An arm 8 of the wippen 6 extends about horizontally over the back end of the key I and carries an adjustable screw 9 contacting a padded upper surface of the key whereby the wippen 6 is turned clockwise around the pivot 1 when the key is struck. Another wippen arm l0 extends from the pivot l in a direction about opposite to the arm 6 and has a slightly upward directed elongation II to which a back check [2 is aflixed.

The back check may comprise a wire I3 which is bendable for adjustment of the position of the back check.

A jack I4 is hinged to the wippen 6 at a pivot point I5 of the arm Ill. The fixed pivot I is positioned between the pivot I5 and the screw 9. A spring I6 has one end positioned in a recess of the wippen 6 or its elongation II and another end positioned in a recess of an angular extension I1 of the jack I4. The spring I6 urges the jack in clockwise direction around the pivot I5.

A fixed, padded stop I8 is positioned below the jack extension IT. A jack trip screw I9 is adjustably inserted in the extension I'I. At the end of a stroke, this screw contacts the stop I8 whereby the jack I4 is slightly turned around the pivot I5 in counter-clockwise direction.

The jack I4 extends from the pivot I5 down in an oblique direction and has a lower end positioned considerably below the level of the key or of the key board. This lower end is provided with a front projection 20 for releasable engagement with a hammer as will be described later. The jack I4 has another projection or nose 2I at its back side which, preferably, is positioned at a distance from the lower end of the jack. This nose 2I serves for the operation of the damper as will be described later.

The hammer has a shank 22 which, in the position of rest, is situated at'a short distance from the jack I6 and of the stop I8 and at the back side thereof. A butt 23 is affixed to the lower end of the shank 22 and has a part 24 passing below the jack I4 and reaching over the front side of the projection 20 whereby the butt forms about an are or a U surrounding an open space 25. The lower end of the jack I4 enters the space 25. The butt part 24 has a recess 26 at that side which faces the front of the projection 20. This recess is releasably engaged by the projection 20 which pushes the part 24 down when the key is struck and the jack moves downward, and pushes the part 24 up when the key is released and the jack moves upward. A fixed pivot 21 is positioned in the butt part 24 farther to the front side than the recess 26 whereby downward movement of the projection 20 turns the hammer in clockwise direction toward a sounding string 28. The pivot 21 connects the butt 23 rotatably to a part 50 which is affixed, by a screw 5I, to a bar 52 forming a part of the pianos stationary structure. The upper and lower surfaces of the recess 26 may be padded with felt layers, and a thin layer 29 of suitable protective material, for example, buckskin, may be placed over these felt layers and adjoining parts of the butts surface.

A head 30 is aflixed to the upper end of the shank 22 and is positioned below the back check in the position of rest. When the hammer swings around the pivot 27 in clockwise direction, the head 30 hits the string 28 in the position shown in dotted lines. When the hammer rebounds from the latter position, a rounded surface 3I of the head 30 engages wedgingly a padded surface 32 of the back check which, at the same time, is positioned as shown in dotted lines.

A hammer rest 33 forms a stop for counterclockwise movement of the hammer. In the position of rest, the shank 22 contacts a padded surface of the hammer rest 33. The latter is positioned in the narrow space between the shank 22 and the fixed stop I8, and suitable clearance is left between the rest 33 and this stop. In order to make this arrangement possible, the

structure of the hammer rest comprises, in contradistinction from the usual wooden bar or rail, a steel rail 34 which has a U-shaped cross-section having short legs bent into tight engagement with the pad of the rest 33. This structure can be made sufiiciently strong without requiring much space in the direction perpendicular to the shank 22 and makes it possible to arrange the jack I4 and the shank 22 about parallel and at a short distance from each other.

A damper comprises a preferably horizontally positioned lever 35 turnable around a fixed pivot 36, a head 31 and a wire 38 connecting the head 31 with the back end of the lever 35. The pivot 36 connects the lever 35 rotatably to a part 53 which is affixed, by a screw 54, to a bar 55 forming a part of the pianos stationary structure. A spring 39 has a fixed end and a movable end 40 entering a recess of the lever 35 and urging the damper into contact with the string 28. The fixed end of the spring 39 may enter a recess of a disk 4I aflixed to a screw 42 which is adjustably inserted in an extension 43 of a fixed part, for example, of the bar 55. The back side of the extension 43 may be padded and may form a rest or stop for counter-clockwise movement of the damper.

A wire, spoon or extension 44 is affixed to the other end of the lever 35 and reaches across the hammer shank 22 into the path of the nose 2I. This nose is positioned over the free end of the wire 44 and forms, together with the lower part of the jack I4, an angle which may be padded. The wire 44 is so adjusted that the surface of the nose 2I hits the free end of the wire at the end of a key stroke.

The described piano action operates as follows:

When the key I is struck, its back end drives the wippen 6 in clockwise direction, raising the wippen arm 8 and lowering the arm I0 and the back check I2. The arm I0 pushes the jack down whereby the projection 20, engaging the recess 26 and pushing the lower surface thereof, turns the hammer around the pivot 21 into the position where the hammer head 2! strikes the string 28 as shown in dotted lines.

The jack trip screw I9, is so adjusted that it contacts the stop I8 a short time before the key stroke is completed and that, when the hammer hits the string, the jack has been turned, by the resistance of this stop, a little in counterclockwise direction around the hinge I5. Thereby, the projection 20 is withdrawn from the recess 26 into the space 25. Simultaneously, the nose 2I contacts the wire 44 and turns the damper a little in counter-clockwise direction around the pivot 36 whereby the damper head 31 is withdrawn from the string 28. Then, the hammer, being disengaged from the projection 20 of the jack, rebounds and is caught by the back check I2 as described before.

When the key I is released, it returns into the shown position of rest. At the same time, the spring I6 urges the wippen 6 back into the shown position, the jack trip screw I9 losing contact with the stop I8 and the projection 20 entering again the recess 26 and pushing the upper surface thereof up whereby the hammer is returned into the position shown in full lines.

I desire it understood that my invention is not confined to the particular embodiment shown and described, the same being merely illustrative, and that my invention may be carried out in other ways without departing from the spirit of my invention as it is obvious that the particular embodiment shown and described is only one of the many that may be employed to attain the objects'of my invention.

Having described the nature of my invention, what I claim and desire to protect by Letters Patent is:

1. In a piano action, a combination comprising a key having a, back end moving up when the key is struck, a wippen having a fixed pivot and two arms extending from said pivot in about opposite, substantially horizontal directions, one of said arms having a lower surface drivingly contacted by said key end, a jack hinged to the other wippen arm whereby said jack moves down when the key is struck, said jack having a lower end positioned considerably lower than said key, and a hammer having a shank positioned at the back side of said jack, and having a butt affixed to the lower end of said shank and engageable by said lower jack end, said butt having a fixed pivot positioned farther to the front side than the point of said engagement.

2. In a piano action, a combination comprising a key having a back end moving up when the key is struck, a wippen having a fixed pivot and two arms extending from said pivot in about opposite, substantially horizontal directions, one of said arms having a lower surface drivingly contacted by said key end, a back check affixed to the other wippen arm, a jack hinged to the other wippen arm whereby said jack moves down when the key is struck, said jack having a lower end positioned considerably lower than said key, and a hammer having a shank positioned at the back side of said jack, having a head afiixed to the upper end of said shank and engageable by said back check, and having a butt afiixed to the lower end of said shank and engageable by said lower jack end, said butt having a fixed pivot posi tioned farther to the front side than the point of said engagement.

3. In a piano action, a combination comprising a key having a back end moving up when the key is struck, a wippen having a fixed pivot and two arms extending from said pivot in about opposite, substantially horizontal directions, one of said arms having a lower surface drivingly contacted by said key end, a jack hinged to the other wippen arm whereby said jack moves down when the key is struck, said jack having a lower end positioned considerably lower than said key, a hammer having a shank positioned at the back side of said jack, and having a butt affixed to the lower end of said shank and having a recess with a lateral opening and having a fixed Divot positioned farther to the front side than said recess, said lower jack end having a projection engaging said recess and being disengageable from the same by turning movement of said jack, and means turning said jack at the end of a key stroke.

4. In a piano action, a combination comprising a key having a back end moving up when the key is struck, a wippen having a fixed pivot and two arms extending from said pivot in about opposite, substantially horizontal directions, one of said arms having a lower surface drivingly contacted by said key end, a jack hinged to the other wippen arm whereby said jack moves down when the key is struck, said jack having a lower end positioned considerably lower than said key, a, hammer having a shank positioned at the back side of said jack, and having a butt affixed to the lower end of said shank and having a recess with a lateral opening and having a fixed pivot positioned farther to the front side than said recess, said lower jack end having a pro-.- jection engaging said recess and being disengageable from the same by turning movement of said jack, said jack having an extension, a spring positioned between said extension and said wippen and urging said wippen and said jack to turn relatively to each other, and a fixed stop positioned in the path of said extension whereby downward movement of the jack brings said extension into contact with said stop and, at the end of a key stroke, said jack is turned against the pressure of said spring.

5. In a piano action, a combination comprising a key having a, back end moving up when the key is struck, a wippen having a fixed pivot and two arms extending from said pivot in about opposite, substantially horizontal directions, one of said arms having a lower surface drivingly contacted by said key end, a jack hinged to the other wippen arm whereby said jack moves down when the key is struck, said jack having a lower end positioned considerably lower than said key, and a hammer having a shank positioned at the back side of said jack, and having a butt afiixed to the lower end of said shank and extending around said lower jack end whereby said butt surrounds an open space entered by said jack end, the front part of said butt having a recess at the side of said space, said jack end forming a projection releasably engaging said recess, said butt having a fixed pivot positioned farther to the front side than said recess.

6. In a piano action, a combination comprising a key having a back end moving up when the key is struck, a wippen having a fixed pivot and two arms extending from said pivot in about opposite, substantially horizontal directions, one of said arms having a lower surface drivingly contacted by said key end, a jack hinged to the other wippen arm whereby said jack moves down when the key is struck, said jack having a lower end positioned considerably lower than said key, a hammer having a shank positioned at the back side of said jack, and having a butt aflixed to the lower end of said shank and engageable by said lower jack end, said butt having a fixed pivot positioned farther to the front side than the point of said engagement, said jack having a lateral projection, and a damper having a fixed pivot and a part reaching into the path of said jack projection,

'7. In a piano action, a combination comprising a key having a back end moving up when the key is struck, a wippen having a fixed pivot and two arms extending from said pivot in about opposite, substantially horizontal directions, one of said arms having a lower surface drivingly contacted by said key end, a jack hinged to the other wippen arm whereby said jack moves down when the key is struck, said jack having a lower end positioned considerably lower than said key, a hammer having a shank positioned at the back side of said jack, and having a butt afiixed to the lower end of said shank and engageable by said lower jack end, said butt having a fixed pivot positioned farther to the front side than the point of said engagement, and a hammer rest positioned between said shank and said jack and comprising a steel rail of U-shaped cross-section.

8. In a piano action, a combination comprising a key having a back end moving up when the key is struck, a wippen having a fixed pivot and two arms extending from said pivot in about opposite,

substantially horizontal directions, one of said arms having a lower surface drivingly contacted by said key end, a jack hinged to the other wippen arm whereby said jack moves down when the key is struck, said jack having a lower end positioned considerably lower than said key, a hammer having a shank positioned at the back side of said jack, and having a :butt aifixed to the lower end of said shank and having a recess with a lateral opening and having a fixed pivot positioned farther to the front side than said recess, said lower jack end having a projection engaging said recess and being disengageable from the same by turning movement of said jack, said jack having an extension, a spring positioned between said extension and said wippen and urging said wippen and said jack to turn relatively to each other, a, fixed stop positioned in the path of said extension whereby downward movement of the jack brings said extension into contact with said stop and, at the end of a key stroke, said jack is turned against the pressure of said spring, and a hammer rest positioned between said shank and said stop and comprising a steel rail of U- shaped cross-section.

ALEXANDER P. BROWN.

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