US2156962A - Piano action - Google Patents

Description

May 2, 1939. w. G. BETz 2,156,962

PIA'No ACTION Filed April 24,v 1937 Patentecl May 2, 1939 UNITED STATES :PATENT OFFICE 12 Claims.

This invention relates in general to piano actions, and more in particular to an action for a so-called miniature upright piano, or, as it is sometimes called, a low-level type of vertical piano and an action related in structure to the structure of my copending application, Serial No. 93,040, filed July 28, 1936.

In the so-called "miniature upright pianos, it has been a difficult problem to provide 1a simple mechanism for Operating the hammer of the piano action so that substantially instantaneous response may be obtained from the striking of a key to accomplish' the striking of a string, and consequently the playing of a note. It has furthermore been a problem to obtain this result in a satisfactory balance of the action so as to require only a relatively light touch on the keys.

There have been other difficult problems to overcome With respect to the installation of theaction and adjustment of the parts. i

It is an object of my invention to provide an improved action for a low-level upright piano.

A further object of my invention is to provide such a device With Simplified mechanism con- 3 nected together and Operating in a manner so as to improve the response between the striking of a key and the movement of a hammer against the string to sound the note and accomplish this improved responseV With a minimum amount of friction in the Operating elements of the action.

A further object of the invention is to provide an action assembled in such a manner that it may be readily mounted in the piano independent of the mounting of the key bed and keys, and

3'5 such an action as to require a minimum amount of adjustment in its parts, but to be readily accessible if adjustment is necessary.

One of the features of the piano action of my invention is the provision of an abstract therefor having a head portion With an extension overhanging a key for direct attack thereon by said key, and a mounting portion With an extension under the Whip of the action for pivotal connection therewith, and a rigid connection between these two portions so that the abstract as a unit is balanced under the strain of attack by the key by virtue of the two extensions being positioned in opposite directions from the rigid connection and thus compensating for the pressures applied at the two portions.

A further feature of Vthis abstract is that it may be readily adapted for use in any size action of this type by merely changing the length of the rigid connection and putting the same head and mounting portions on each rigid connection.

Other objects and advantages of the invention Will be apparent from the following description, taken With the drawing, in which:

Fig. 1 is a fragmentary side elevation of an action for a single key of the piano.

(ol'. s4 240) Fig. 2 is a similar view of a modification thereof.

Although the invention may take numerous forms, only two have been illustrated herein. The structure of Fig. 1 includes a key lfl mounted 5 in the normal manner on a key bed of a piano, lto actuate mechanism for striking a string ll mounted on a plate 12 of an upright piano in the usual manner to accomplish playing of said piano. Only one action has been illustrated in 10 each figure, but it is understood that a similar action is provided for each key over the entire scale of the piano.

The action is supported on a mounting bracket I 3 carried at the top in the usual manner from a supporting bolt (not shown), and carried at the bottom on a rail M. Mounting means intermeciiate the bracket and the action itself include a Whip rail 'secured on to the bracket l3, and an abstract rail H to Which the abstract mechanism is pivotally connected, as Will be hereinafter described.

Upon hitting the key I, the movement thereof is transmitted through a capstan 18 to a Wcoden abstract head l, which is mounted on rigid steel Wire connection 2 I, and the latter is H rigidly supported in a Wooden abstract pivot member 22. The abstract head [9 and pivot member 22 may be threadably secured to the Wire: 2! in the usual manner, and pointed in opposite V directions as illustrated in Figs. 1 and 2. Neck or mounting portions extending .downwardly and upwardly respectively on the members l9 and 22 increase the rigidity of the securing or mounting of such members on the Wire 2| and by virtue of* their length stiffen the Wire itself. With this assembly, the length of the entire abstract may be varied to fit any size action by merely shortening or lengthening the Wire 25. The abstract= pivot 22 is pivoted from a Whip 23 at an integral extension 22' thereof, by means of a pivot pin 26 extending through said extension and the side Walls 21 of a U-shaped cavity portion 28 in thelower portion of the whip 23. The Whip 23 is pivotally mounted at 24 on a Whip flange Zi 45 Which in turn is rigidly supported from the whip rail IB.

A fly 3I, for engaging the hammer butt 32 of the hammer 33 to pivotally move the latter, is pivoted at 34 to a flange 36, Which flange is rigid- 'i ly mounted on the Whip- 23. As Will be noted from an examination of both figures of the drawing, the pivot point 34 of the fly 3] is in direct alinement with the pivot point of the abstract pivot member 22 at 26. With this arrangement, the 35 fulcrum of the abstract pivot member is in line with the fulcrum of the fly that delivers the stroke to the hammer, that is, both pivot points are on the circumference of a circle draWn With the pivot point 24 as the center of the circle.

The motion of the whip 23, pivoted from the flange 29, is, after all, pivotal, but With the fulcrum of the abstract pivot member 22 under the pivot of the fly 3| and therefore in substantial alinement With the fulcrum of the fly, the motion of the key i!! is transmitted directly to the fly 3! and in turn to the hammer 33. With the direct attack, first of all, on the abstract head |9 by the key, then through the abstract to the fly, and then to the hammer, there is no lost motion in the action, friction, nor weight such as to require more than a very light touch on the key. With this action it has been found that a shorter key lll may be employed, thus reducing the total depth of the piano casing for the action. The hammer 33 is pivoted from a fiange 31, Which in turn is Secured on the Whip rail IG, while the usual back check 38 is mounted on the Whip 23 to act in the usual manner on the catcher 39 on the butt of the hammer. In the released position of the action, the hammer shank rests against a felt pad or cushion on the hammer rail 4| in the usual manner.

Referring further to the abstract assembly, the abstract head iQ is pivotally connected to the rail ll by means of a pivoted fiange 43 and a stationary flange 44. The flange 43 stands at an angle With the fiange M and head 19 in the release position of the action, and the abstract head I9 will move slightly forward and upward in an arc on the movement of key Ii), with the capstan IS in direct striking engagement With the abstract head IQ. The head IE pivots at on the flange 43 extending into a U-shaped cavity in the top of the head, and this flange pivots on the flange 44 at 45. In the meantime, during the striking action, the Whip 23 is being raised and the member 22 pivoted With respect thereto so that the pivot action of the abstract is accomplished through a plurality of points. In this respect, the abstract head 19 follows the capstan l and friction between the capstan and abstract head is reduced to a minimum to make the playing action of the piano far more sensitive. The construction of the three-part abstract and its counterbalanced mounting in the action also contributes to the playing efficiency of the action, and sensitivity. In this connection it is noted that the portion IQ' on the abstract i!! and integral therewith, or at least rigid With respect thereto, extends forwardly from the connector wire 2! over the key HI, while the integral extension 22' of the pivot member 22 extends rearwardly from the Wire 2! to lie under the whip 23 and be pivotally connected thereto at 26 as previously described. As a result of this construction, the strain on the wire 2| is equalized, the wire remains straight and the abstract rigid When transmitting motion from the key lO to the hammer 33, and the action, besides operating at maximum efficiency as previously described, also stays in regulation.

The piano action of my invention, in a modified embodiment, is illustrated in Fig. 2 in the released position, With the top of the fly 5| engaging an edge 59 formed by two angularly extending cushioned side Walls on the butt 58 of the hammer. As the abstract is raised upon striking the key IB, the Whip 23 is pivoted up- Wardly and the fly 51 pivoted from the Whip raises the hammer butt 58 to raise the hammer in the usual manner. At the end of the stroke, the cushion 53 of the fiy 5! engages the corresponding cushion 54 of the back check 56, and because of an inherent flexibility or resilience in aisaoez I i...

the substantially U-shaped mounting wire 51 for the back check, there is a slight movement in the back check 56 to provide a live reaction in' the recoil of the elements of the piano action. Furthermore, the relatively large surface of the back check block 55 itself is very effective in Stopping the movement of the fly 5! in the most desirable manner. The mounting U-shaped Wire 51 may be readily bent up or down in the U-portion for adjustment to move the check 56 toward or away from the fiy 5! to provide the proper adjusted position of the entire mechanism.

An adjustable stop El is supported from a lug 62 carried in the rail 16 for adjustment to provide the proper Stopping action on the butt of the fly 5I.

In the present invention, therefore, a simplified piano action is provided, which .is mounted independently of the key board. This facilitates the original assembly of the piano, as Well as making the subsequent regulation of the piano action very simple, for the regulator may remove the keyboard without touching the piano action for such removal. The abstract construction itself and its mounting in the entire action makes possible the transmission of the motion of the key in a direct manner to the hammer, and the entire action is compressed from front to the rear in the piano, Without sacrificing the playing efficiency thereof. This all makes possible a shalloW, that is from the front to the rear, piano casing, thus reducing the cost of the piano and in general providing a neater appearing device. There being no adjustments necessary in the abstract mechanism, there are no parts thereof '1 Which Will become loose in use, and therefore the piano action will operate With a minimum of noise during its entire life.

Although the invention has been described in its preferred embodiments, it is understood that it is not limited thereby, but is limited only by the scope of the appended claims.

I claim:

1. A piano action for each key of a piano, said action including a pivoted whip, a fly pivoted therefrom, a hammer adapted to be actuated by movement of the fly, and means for transmitting the motion of a piano key to the hammer including a three-member abstract having a head member with a portion rearwardly of the rear end of the key and With a rigid forward extensoin thereon overhanging the key for direct attack thereby, an upright connecting member rearwardly of the rear end of the key and extending downwardly from the head member to a pivot member supporting said connecting number and having a rigid rearward extension for pivotal connection to said whip.

2. A low level type upright piano having a plurality of keys, an action for each key, and supporting means for the actions including an abstract rail, each action including a pivoted hammer and means for actuating the hammer, said means including an abstract having a head with an integral key attack extension, and an abstract guide flange pivotally connected between said abstract rail and said abstract head extending upvvardly and rearwardly from the head, With the attack extension and the pivotal abstract flange extending from portions rear- Wardly of the rear end of the key and overhanging the rear end of a key, and with the remainder of the entire action and of the supporting means including the abstract rail entirely rearward of the rear end of the key.

3. In a low level upright piano, a plurality of keys, action supporting means, including an overhead abstract rail rearwardly of the rear ends of the keys, an action for each key including a pivoted hammer, a pivoted whip, and means for actuating the Whip including an abstract having a head overhanging the rear end of a key for attack thereon by the key, a foot lying below the key and pivoted to the Whip, a connecting member extending between the head and foot, with said head and foot each rigid With respect to said connecting member, and guide means for said head pivoted at the overhead rail and to the head to maintain said head over said key.

4. In a piano of the loW level upright type, a plurality of keys, a piano action, and means for supporting the action in the piano including a horizontal abstract rail extending transversely of the length of lthe piano keys and positioned rear- Wardly of said keys, said piano action having a hammer and means for transmitting motion of the key to the hammer, including van abstract having a downwardly extending portion, a head portion rigid With respect to said downwardly extendng portion, and a guide flange for said head portion pivotally connected at the abstract rail and pivotally connected to the head portion of the abstract.

5. In a piano having a plurality of keys, an action for each of said keys, and means for supporting the action, including an abstract rail above the keys and rearwardly thereof, said action including an abstract having a downvvardly extending lift portion and a key attack portion above the lift portion and rigid With respect thereto, and a guide fiange for said abstract connected for pivotal movement at said abstract rail and pivotally connected to the key attack portion.

6. In a piano, a plurality of keys, With each key having a strikng portion at the rear thereof, a playing action for each, and a supporting bracket for such action positioned entirely to the rear of the keys, each action including a pivoted Whip, a pivoted hammer, and an abstract having an upright portion positioned rearwardly of the key and pivotally connected to said Whip, said abstract including an attack portion extending forwardly over the keys and non-pivotally connected to the upright portion thereof, to be struck by the striking portion on a key to lift the abstract, and pivoted supporting means for said attack portion connected at the rear thereof and extending rearwardly and upwardly away from said portion for connecting to the supporting bracket to the rear of the keys.

7 In an upright piano, a plurality of keys, an action for each of said keys, and supporting means including an abstract rail for said action spaced rearwardly from the end of the keys, each of said actions including a pivoted Whip, an abstract pivotally connected to said Whip and extending upwardly in a line intermediate said abstract rail and the rear end of a key to a head portion overhanging such rear end, and a pivoted finger extending forwardly from said rail to connect with said abstract head and maintain said head centered over the rear end of the key.

8. An abstract for a piano action including in combination, an inverted substantially L-shaped head With one leg in the L-shape comprising an attack portion for engagement by a piano key and the other leg of the L-shape comprising a mounting portion, a connecting member nonpivotally secured in said mounting portion of the head and extending away therefrom in alignment therewith, and a substantially L-shaped rigid abstract mounting member With one leg of the L-shaped mounting member having a cavity for receiving the connecting member and rigidly securing the same therein and the other leg of such L-shaped mounting member comprising a mounting portion for connection into the piano action and With each of said legs of the L-shaped mounting member adapted to remain continuously rigid relative to one another during the Operating movement of the abstract.

9. In a piano action for upright pianos having a keyboard extending to the front of the piano and supporting means for said action at the rear of the piano, a Whip rail on said supporting means, and a Whip pivotally supported from said rail. a hammer fly pivotally supported from the Whip and positioned above the whip, means for pivoting said Whip about the pivotal supporting point therefor to raise the fly, said pivoting means comprising a key engaging abstract having an upright portion and having a mounting portion With the latter having a cavity therein for receiving and rigidly supporting said upright portion and providing a non-flexible connection at the mounting portion from said upright portion to said Whip, transverse pivot means for pivotally connecting the abstract to the Whip at the mounting portion of said abstract.

10. In a piano action for an upright piano having a pivotal key, said action including a pivoted Whip, and means providing a counterbalanced motion transmitting structure intermediate the key and Whip for pivoting the vvhip, said means comprising a substantially Z-shaped unit having a head portion positioned rearwardly of the rear end of the key With a forward extension for positioning over the end of a key for striking engagement thereby and a downward extension at the rear of the forward extension, a connecting portion normally positioned rearwardly of the rear end of the key secured in said downward extension, and a pivotal mounting portion for said unit having an upward extension apertured to receive and retain said connecting. portion therein and having a rearward extension at the rear and bottom of said upward extension for pivotal connection With said Whip.

11. In an action for a piano having the usual keyboard with a plurality of keys, mounting means for said action, a pivoted Whip, an abstract for each of said keys pivotally supported on said Whip having a head portion With an integral key striking portion overhanging the rear end of said key, and means for supporting and centering said abstract over said key, said means including a support link extending rearwardly and slightly up- Wardly from said abstract to a fixed support member on the piano.

12. In a piano action for an upright piano, a hammer and means for actuating said hammer including a pivoted Whip, an abstract comprising a rigid one-piece head positioned substantially rearwardly of the rear end of the key and having a portion extending over the end of the key of said piano for direct attack thereby, a pivot member below said key having a rigid pivot extension extending in a direction opposite to the attack portion of the head for direct pivotal connection With said whip, and a substantially rigid connecting member extending dovvnwardly from said head to said pivot member and positioned over its length rearwardly of the rear end of the key.

WILLIAM G. BETZ.

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