US2297717A - Piano action - Google Patents

Description

J. C. POTWIN Oct. 6, 1942.

PIANO ACTION Filed Sept. 30, 1941 2 SheetsSheet 2 UNITED STATES PATENT OFFICE PIANO ACTION Julian C. Potwin, Ivoryton, Conn., assigner to Pratt, Read & Company, Ivoryton, Conn., a corporation of Connecticut Application September 30, 1941, Serial No. 413,020

Claims.

This invention relates generally to piano mechanism and in particular to a piano action of drop type for a low upright piano.

It is an object of this invention to provide an improved drop type action for a low upright piano.

Another object of this invention is to provide a piano action of drop type having an improved abstract and whip assembly.

A further object of this invention is to provide piano mechanism including a key and a piano action having a whip, in which the key is operatively connected with the action by an abstract which is arranged in direct striking engagement with a pivoted whip and pivotally connected into the action so as to be transportable with the action as a unit when disconnected from the key.`

Yet another object is to provide an improved action comprised of but few parts, compactly assembled with a minimum number of frictional connections and adjustable portions, to provide for a long operating life with little attention and replacement of parts and an improved repeating action of the piano key.

A particular feature of this invention is found in the provision of a piano action having a pivoted Whip and abstract foot portion arranged for striking engagement, but relatively formed so that a rocking action occurs therebetween simultaneously with the pivotal lifting of the whip by the abstract. Any friction between these parts tending to restrict their free movement is thus practically eliminated.

Another feature of this invention is found in the provision of an abstract comprised of a wire lifter with end members secured thereon, in which each end of the wire is hooked for anchoring in a corresponding member and each member is grooved so that corresponding hooks and grooves cooperate to retain a corresponding end member in a xed position on the abstract lifter.

Further objects, features and advantages of this invention will become apparent from the following description when taken in connection with the accompanying drawings in which:

Fig. l is an elevation partly in cross section of one of the units of a complete piano action showing the improved abstract and whip assembly of this invention in one operating position;

Fig. 2 is a fragmentary view illustrated similarly to Fig. 1 showing the parts thereof in changed position;

Fig. 3 is a fragmentary elevational view of the abstract head member in Fig. l as seen along the lines 3--3 in Fig. 1;

Fig. 4 is a fragmentary elevational View of the abstract foot member as seen along the line 4 4 in Fig. 1;

Fig. 5 is a fragmentary elevational view of a piano action unit similar in all respects to Fig. 1 but having an abstract of a modied form;

Fig. 6 is a plan view of the head portion of the modified abstract as seen along the line 6 6 in Fig. 5; and

Fig. '7 is a bottom view of the foot member of the modified abstract as seen along the line 1-1 in Fig. 5.

In the practice of this invention there is provided a drop type piano action having a plurality of abstracts, all simultaneously connectible, or disconnectible with corresponding piano keys as an incident to the assembly or disassembly, respectively, of the action and piano keys. Each of the abstracts is provided with a foot portion extending longitudinally in a direction from front to rear of the piano action and pivotally connected intermediate the ends thereof into the piano action. One end of the abstract foot portion is arranged to underlie a portion of a corresponding pivoted whip, the adjacent surfaces of the abstract foot portion and whip being reversely curved and arranged in striking engagement, the engaging surfaces providing for a rocking action between the whip and abstract simultaneously with the pivotal lifting of the whip by the abstract. Because of the pivotal connection of the abstract foot portion in the remainder of the piano action, and its releasable connection with a corresponding piano key, the abstract on disconnection from the key is readily adapted to be transported or moved about with the remainder of the piano action as a unit.

There is shown in Fig. 1 a piano action including a supporting rail I 0 which in turn is mounted on a plurality of mounting brackets (not shown). A whip I2 is pivotally connected to the rail I0 and in turn pivotally supports a jack I3. As the whip I2 is raised the jack I3 engages, in the usual manner, the butt I6 of a hammer I4, this motion being transmitted through the jack to pivot the hammer into striking engagement with a corresponding piano string. A back check I'I and bridle strap wire I8 are both supported on the whip, which is operatively connected with a corresponding key I9 by an abstract 2| having a head portion 22 and a foot portion 23 connected together by a Wire lifter 24.

The head portion 22 extends longitudinally in a direction from front to rear of the piano action, with a portion thereof overhanging and in operative engagement with a capstan 26, which is mounted near the rear end of the key. As shown in Figs. l and 3 the upper end of the wire lifter 24 is of substantially hook or U-shape, the free end portion 21 thereof being anchored in the head or end member 22 and positioned transversely thereof. A groove 28 extending in the direction of the lifter wire 2Q is formed in the longitudinal side 29 of the head portion 22 and extends substantially transversely thereof. The groove 28 is arranged substantially normal to the anchored portion 21 of the lifter 24 and is adapted to receive therein the straight or base portion 3l end of the lifter being bent so as to position the intermediate or body portion of the lifter wire 24 substantially between the longitudinal sides 28 and 33 of the end member 22. By virtue of the anchoring of the lifter wire in the head end 22 and the disposition of a portion thereof in the groove 28 the head portion 22 is fixedly secured to the lifter wire.

The abstract foot portion 23 also extends longitudinally in a direction from front to rear or transversely of the piano action and is pivotally connected intermediate its ends 3A and 36 by an axis member 31 to guiding or retaining means designated generally as 38. The retaining means 38 is comprised of an arm 39 mounted at one end on a rail member 4I comprising part of the piano action, the opposite end 42 of the arm 39 being pivotally connected by an axis member 43 to one end of a lever 44. The other end of the lever 44 is pivotally connected to the abstract foot portion by the axis member 31.

The end 311 of the abstract foot portion is secured tothe lower end of the lifter rod which as seen in Fig. 4, is hook-formed similarly to the upper end hereinabove described, with like reference characters being used to designate corresponding parts. It is seen, therefore, that the. end members 22 and 23 are rigidly secured to the Wire lifter 24 to provide a substantially integral abstract unit, with the body portion of the lifter 24 intermediate the end members 22 and 23 being of substantially straight form.

The end 35 of the end member or foot portion 23 underlies the end portion 46 of the whip I2 and is formed along its upper side with a reversely curved surface 41. The under or lower side of the whip end 85 is provided with a corresponding reversely curved surface 48 adapted to fit in mating engagement with the surface 41. The surfaces 41 and 48 are separated by a felt or like bushing I9 secured to the whip I2 and functioning toV quiet the striking or abutting engagement of such two surfaces during the operation of the piano mechanism. From a consideration of Fig. l, therefore, it is seen that the head portion 22 is free 0f the piano action and overhangs the capstan 28 in abutting engagement So as to be readily connectible and disconnectible therefrom, with the foot portion of the abstract being pivotally connected with the piano action by the retaining means 38 and having a portion thereof in an underlying position relative to the whip I2 and in direct engagement therewith. On disconnection of? the abstract and key, therefore, the abstract .remains connected with the piano action.

The abstract 2I duringplaying movement thereof is guided in a substantially up and down direction by means including a rail member I having adjustable guide elements 52 thereon individual to each abstract 2|. The guide rail 5I is removably of the lifter end, the other leg 32 of the U-shaped secured to the key frame 53 and rearwardly thereof, and in Fig. 1 is shown removed from the key frame and in a position for simultaneously moving all of the abstracts 2I out of an engaging position with a corresponding key I9 and towards@ the remainder of the piano action. With the rail member 5I retained in a position adjacent the piano action by suitable means (not shown) all ofl the abstracts 2| are transportable with the action: as a unit for shipping and assembly purposes.

As shown in Fig. l the key I9 is in a rest posi-- tion, with the Zone of engagement between the abstract foot portion 23 and whip I2 at the surfaces 21 and I8 being substantially above the axis' member 31. On depressing or playing of the key the abstract 2i is lifted upwardly to in turn pivotally lift the whip I2. As the whip I2 is raised the zone of engagement between the curved surfaces 41 and 88 moves outwardly toward the extremity of the abstract end 35, as shown in Fig. 2, by virtue of the rocking action provided between the whip I2 and end member 23 by such curved surfaces. Frictional resistance between the engaging portions of the abstract and whip is thus practically eliminated, since the rocking action occurs simultaneously with the lifting of the whip I2. An operation of the piano action is thus accomplished which improves the repeat action of the key I9, this improved operation being facilitated by the reduced number of pivotal connections utilized in the assembly of the abstract 2 I, and the consequent reduction in the number of parts to be set or regulated in the adjustment of the abstract 2l. By virtue of this simple and compact construction and arrangement of the abstract 2I and whip I2, the initial adjustment of the abstract is not changed when the abstract is disconnected from the key for transporting or assembly purposes and is positively maintained over a long operating period.

Referring to Figs. 5, 6 and '7 there is illustrated a piano action which is similar in all respects to the action shown in Figs. l and 2 except for a modified form of abstract 2|. The head member 22' operatively engages the capstan 28 in a manner similar to that described for the vhead member 22, and extends longitudinally in a direction from front to rear of the piano action. A groove 56 in a longitudinal side face 51 extends in the direction of the lifter wire 24 and substantially transversely of the head member 22. A second groove 58 formed in the top side 59 of the head member 22 is arranged normal to the groove 55 and in communication therewith. The upper end of the lifter rod 24' is of substantially hook or U-shape, the free end 62 Vthereof being anchored in a substantially vertical direction in the head member 22 and the remaining portions thereof being disposed within the grooves 56 and 58. As is best seen in Fig. 6 the groove 58 is of a depth such that the body portion of the lifter wire 24 is positioned substantially intermediate the longitudinal sides 51 and 63 of the head member in a substantially up and down direction.

The foot member 23 has a substantially transversely extending groove 84 formed in the longitudinal side 68 thereof for receiving a portion of the lower end of lifter wire 2li', which is of substantially U-shape, the free end 61 thereof being anchored in a substantially vertical direction in the foot member 23. From a consideration of Figs. 6 and 7 it is evident that the lifter rod 24' is of straight form over substantially its entire length with the bent ends thereof extended in opposite directions normally therefrom and longitudinally of the end members 22 and 23. Each end 62 and 6l of the lifter wire 24 is firmly anchored in a corresponding one of the end members 22 and 23', respectively, with the lifter wire portions substantially adjacent to such ends being disposed in corresponding grooves formed in the end members. There is thus provided a simple and rugged abstract member of substantially unit construction.

The invention thus provides for an improved abstract which is readily connectible or disconnectble from a corresponding key and assembled for direct engagement with a corresponding whip in the piano action in a manner such that the abstract on disconnection from the corresponding key is transportable With the piano action as a unit. The engaging portions of the abstract and whip are of a relative form such that a rocking action occurs betwen the whip and abstract concurrently with the pivotal lifting or raising of the whip by the abstract. Frictional resistance between the abstract and whip is thus substantially eliminated. The number of pivotal connections utilized in the assembly of the abstract are reduced to a minimum so that the initial adjustment of the abstract relative to a corresponding whip and key and the efficient operation of the action is positively retained over a long operating life.

Although the invention has been described with specific reference to a preferred embodiment thereof, it is to be understood that it is not to be so limited since changes in the various parts and their assembly can be made therein which are within the full intended scope of the invention as defined by the appended claims.

I claim:

l. An abstract for a piano action including a wire lifter and an end member at one end of the wire lifter having longitudinally extending side faces, with a groove in one of said faces extending in the direction of said lifter and substantially transversely of said end member, said lifter being of substantially hook shape at said one end, with the free end of said hook anchored in said body member, and at least one other portion of said hook being disposed in said groove to retain said end member in a fixed position on said lifter wire.

2. An abstract including a wire lifter with a substantially straight body portion and an end portion of substantially U-shape, an end member secured to said end portion having longitudinally extending side faces and a groove in one of said side faces extending in the direction of said lifter body portion and substantially transversely of said end member, with one leg of said substantially U-shaped end portion being anchored in said body member and extending transversely thereof, and at least a portion of the base of said U-shaped portion being disposed in said groove, the other leg of said end portion being of a form to position the body portion of said wire lifter substantially intermediate said side faces.

3. An abstract with a wire lifter including an end member at one end thereof having side faces, with one of said side faces having a groove therein extending in the direction of said lifter and substantially transversely of said end member, and another side face adjacent said first side face having a groove therein normal to said rst groove and in communication therewith, said lifter having a hook portion at said one end substantially parallel with said first groove and in an anchored position in said body member, and another portion bent for disposition in said two grooves to retain said end member fixed on said lifter wire.

4. An abstract including a wire lifter and an end member at one end of the wire lifter having longitudinally extending side faces, with a groove in one of said side faces intermediate the ends of said end member extended in the direction of said lifter wire, said lifter being of hook shape at said one end thereof, with the free end of said hook anchored in said end member, and `at least another portion of said hook being located in said groove and confined therein against any movement longitudinally of said end member, and cooperating with said anchored hook end to retain said end member in a xed position on said lifter wire.

5. An abstract for a piano action associated with a corresponding piano key for applying a force on the abstract to actuate the same for a playing operation of said piano action, said abstract including a wire lifter movable in a substantially up and down direction, a body member at one end of said lifter wire having a side face with a groove therein extended in the direction of said wire lifter and said groove defining a portion on the body rearwardly of the groove comprising a projection relative to the vbottom of the groove, said wire lifter at said one end having a part extending in a different direction than that of the groove anchored in said body member, and a second part receivable Within said groove through the open lengthwise top thereof, a portion on said body member to one side of said groove adapted to be operatively connected with said key, and a second portion on said body member including said projection acting as a stop for said second part in said groove to retain said second part of the wire lifter rigid in the body member on application of the force from said key on said body member.

JULIAN C. POTWIN.

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