US2236614A - Piano - Google Patents

Description

April 1941. F. A. WESSELL, JR

PIANO Filed May 18, 1938 WITNESS ATTORNEYS Patented Apr. 1, 1941 UNITED STATES PATENT @EFFEQE PIANO Fernando A. Wessell, Jr., Red Bank, N. J.

Application May 18, 1938, Serial No. 208,567

3 Claims.

.. requirements imposed by the modern technique .l

and which can be readily assembled and adjusted in the piano with a minimum of effort.

In the construction of an upright piano, it is necessary that the operating parts be incorporated therein in a certain definite relationship in order that the piano will have a good tonal quality and will satisfy the numerous requirements of the modern technique. One of thes requirements is that the key touch, which is the normal amount of force that the finger or the player applies to a key in order to obtain from the string the desired vibrating power and resonance, should be approximately two ounces to three ounces and this is standard for all pianos. The depth of touch or drop is also standard and all modern pianos have a depth of touch of approximately to 1% of an inch. The leverage of the key levers in modern upright pianos is such that a key lever will lift one end of the wippen operatively connected to its inner end, two-thirds of the distance that the key lever is depressed, as this ratio has been found by experience to give the most satisfactory results.

' The key levers of a modern upright plane, therefore, are usually constructed and balanced so that the weight arm of the key lever and the power arm thereof will be in the proportion of two to three. The actions in an upright piano are usually so constructed and arranged with relation to the key levers that the wippens thereof will rotate upwardly through a predetermined angle as the weight arms of th key levers are rotated upwardly so that when a key is depressed by the player, the associated key lever weight arm and action will rise with a minimum amount of friction from below center. The relationship of all the lever arcs of the several] parts of the action also must be maintained with scientific exactness to enable such parts to move relative to one another with a minimum of friction and to obtain the most satisfactory results with the modern requirements of key touch, depth of touch, key lever leverage, and the amount of force with which the hammer hits the string at its striking point. The hammer blow is, of

course, dependent upon the size of the hammer, the amount of force imparted to the hammer butt by the key lever through the action and the distance through which the hammer head has to travel. Experience has demonstrated that in an upright pianothe hammer head should travel approximately 1%, to 1% inches in order to giv the string a blow suitable to impart the desirable vibrating power .to the string. Another requirement that has developed through long experience in this art is that the jack or fly should be pivoted outwardly away from the hammer butt when the hammer head is Within to of an inch of completing its travel toward its ass ciated string after a key has been depressed in order to enable the hammer to rebound freely from the string after it has delivered its blow while yet maintaining a. proper timing of the coacting parts so that they will function satisfactorily during the playing of the piano. It will be evident therefore that the arrangement of the operating parts in an upright piano suitable for the modern technique involves a satisfactory fulfilment of numerous requirements and that such parts are so arranged that even a slight modification of any one of them may materially affect the operation of the piano and render it unsuitable for the modern technique. These requirements apply to every action and its associated parts in order that there will be provided a uniformity of key touch, depth of touch, key lever leverage, action operation, and hammer blow throughout the piano.

At the present time, there is practically no demand for the heretofore satisfactory regular upright or vertical piano because of its bulkiness and in an effort to meet the modern ideas of interior decoration, piano manufacturers have been obliged to considerably reduc the size of the upright piano so as to provide the smallest practical instrument. This result has been obtained, so far as I am aware, not by changing the coordination and relationship of the parts of the actions which had attained perfection after long years of often expensive experience, but by changing the size and/or arrangement of the strings, string plate, and sound board of the piano or by dropping the action mechanism to a plac between the inner ends of the key levers and the strings or below the key levers. While such prior small piano constructions have proven fairly successful, they have not been completely satisfactory for several reasons. For example, in those small pianos whose size has been obtained solely by dropping the action mechanism tends up through the key lever,

to a position between the inner ends of the key levers and the strings or below the key levers, the changed position of the actions brought into being other disadvantageous factors which were not present in the standard upright piano, such as interference of the mechanisms which connected the actions to the key levers with the operation of th actions or key levers, difficulty in adjustment or replacement of parts, etc. Furthermore, the connections devised for the actions and key levers of these small pianos are of a complicated nature or possess inherent faults which made their use in a piano not entirely satisfactory.

In studying this problem it occurred to me that it might be possible to reduce the height of the upright piano sufficiently for modern decorative purposes and still retain the advantages of the regular upright by reducing the size of the action itself. could not by merely reducing the dimensions of the several parts of the regular upright action expect to obtain a satisfactory action which would fulfil the requirements of the modern technique but I found after further study and experimentation that if in addition certain substantial and radical changes in the arrangement and construction of the parts comprising such act-ion were made, such a result could be accomplished. These changes, while apparently very simple, have enabled me to considerably reduce the size ocf the standard upright piano without positioning the action intermediate the strings and the key levers or below the latter, or necessitating the use of additional connecting mechanisms and to provide a compact action arrangement which is of simple construction, can be readily arranged and adjusted in the small modern cases, will function in a. most reliable and satisfactory manner and will fulfil all of the requirements imposed by th modern technique.

For a better understanding of my invention, reference is to be had to the following description taken in connection with the accompanying drawing in which Fig. l is a side elevation of an in dotted outline at their innermost position afterthe key has been struck and the rod 66 being shown in dotted outline at its uppermost position as a result of depressing a foot pedal of the piano, to illustrate the coa-ction of such outlined parts in sustaining individual notes or chords, and Fig. 3 is a detailed view of the improved fly or jack utilized in my action, the jack being shown in full size.

In the drawing, the reference character It designates the key lever which is supported intermediate its ends'upon a block H mounted on the baseboard I2 of the piano. The key lever i is pivoted to rock on the block II in the customary fashion by means of a pin l3 which ex- A cushion I4 of felted material is provided on the baseboard [2 to support the inner end of the key lever in its normal or at-rest position as shown in Fig. 1 and a felt washer I5 is mounted on a stud 16 for controlling the depth of touch or drop of the My experience told me that I A key provided on the outer end of the key lever ID. This construction is similar to that of an ordinary upright piano, the length of the weight arm of the key lever with relation to the length of the power arm thereof being in the ratio of 2:3 and the depth of touch being approximately {a of an inch. The inner end of the key lever, however, unlike the ordinary upright key lever, is reduced in thickness to approximately half the thickness of the remaining portion of the key lever. Secured upon the inner reduced end of the key lever is a capstan screw ll arranged to engage with a felt pad ll provided on the underside of a wippen H3.

The wippen I8 is pivotally supported at I8 by a depending wippen flange l9 which is secured at its upper end to the lower portion of an action rail 2!). Fastened to the upper rear portion of the action rail 2!] is a hammer flange 28 which pivotally supports at its upper end a hammer butt 22, the latter of which carries the shank 23 and the hammer 24, the shank 23 resting against a rail 25 when in its normal or atrest position, as shown in Fig. l. The hammer butt 22 is provided with the usual cushion 26 and the upwardly and outwardly inclined cushioned surface 2?. It is to be observed at this point that the hammer butt 22 and the hammer 24 ar of standard size but the shank 23 has been considerably shortened in length and is approximately 2% inches long.

The cushions 26 and 27 are engaged by the upper end of a jack 28 which is pivoted at its lower end to the upwardly extending standard 28 carried by the wippen IS, the pivot of the jack being designated by the numeral 33 in Fig. 3 of the drawing. The upper end of the fly or jack is normally held against the cushions 26 and 21 and in the corner formed by said cushioned surfaces by means of a spring 3B which is positioned between an outwardly extending arm 3| formed on the lower end of the jack and the upper surface of the wippen I8 as shown more clearly in Fig.2. Just above the arm 3| is supported a stop 32 with which the arm 3| is adapted to contact during the upward movement of the whippen 18 under the action of the key lever 10. It will be evident from the drawing, as thus far described, that when the key is depressed to lift the inner end or weight arm of the key lever, the wippen l8 will be rotated about its pivot l8 to lift the jack 23. The upward movement of the jack will force the hammer butt 22 about its pivot and cause the hammer 24 to strike the piano string 49 a blow, As soon as the arm 3| of the jack engages with the stop'32 during the upward movement of the wippen l8, the upper end of the jack 28 will be caused to swing outwardly along the cushioned surface 21. As is the case with a standard upright action this operation occurs when the hammer head which has a travel of approximately 1% inches is within from to of an inch of completing its travel to the string 49 as is illustrated by the dotted position of the hammer head 24 in Fig. l of the drawing.

The point of engagement or contact of the arm M with the stop 32 is indicated in Fig. 1 by an arrow. As will be observed more clearly in Figs. 2 and 3 of the drawing, the recessed portion 35 on the underside of the arm 3| for receiving the upper end of the spiral jack spring 39 is positioned at a distance from the pivotal point 33 of the jack so that the lever arm from such pivotal point to the center of force of such operated to strik the piano wire.

spring is greater than the length of the lever arm between such pivotal point and the point of contact 34. This is clearly illustrated in Fig. 3, where the broken line 36 indicates the lever arm between the pivotal point 33 and the center of force of the spring 39.] and the broken line 31 indicates the lever arm between the pivotal point 33 and the point of contact 34. I have found that contrary to the long established practice with respect to standard actions, the leverage exerted by the jack spring in a compact action such as the one with which this invention is concerned should be at least as great as the lever arm between the pivotal point of the jack and the point of contact of the jack arm with the stop and preferably should be greater in order to obtain a proper movement of the jack and a proper coordination and operation of the key lever, wippen, jack and hammer. By reason of the fact that the center of force of the spring 30 (see the double headed arrow in Fig. 2) is outside the point of contact of the jack arm with the stop or abutment member 32 in all positions of the jack during its upward and lateral movements, the jack will be biased at all times about the pivot 33, in a counter-clockwise direction, as viewed in the drawing, and towards the cushion or lateral stop 26 on the hammer butt 22. This will be true even during the intervals that the jack is engaged with the member 32. Thus there is insured an immediate complete return of the jack to the lateral stop 26 on each release of the associated key. I have also found that it is necessary for a proper operation of these parts that the length of the lever arm between the point of contact 34 and the pivotal point 33 should be one-fifth the length of the lever arm between the pivotal point 33 and the point of contact of the jack with the cushion 27, such latter lever arm being indicated by the broken line 38 in Fig. 3 of the drawing. By maintaining the above-mentioned relationships, I found that I was enabled to provide a compact action mechanism which, while considerably smaller than the standard mechanism, satisfied all the long established requirements for a standard upright action and operated in a manner comparable to the latter.

The stop 32 is mounted on a stop or regulating rail 39 in such manner that it may be adjusted vertically to the proper position for regulating the movement of the jack. The rail 39 which is supported on the action rail 2|] by means of a plurality of outwardly extending arms 40 is arranged with respect to the fly or jack that it also functions as a stop or block to the outward pivotal movement of the jack, the latter engaging with the felted cushion 4| provided on the inner face of the rail and extending the full length thereof. The rail 39 as thus arranged serves the dual purpose of providing a support for the vertically adjustable stop and insuring a proper operation of the jack every time the key lever functions.

A downwardly and outwardly extending inclined rod 42 is connected to the hammer butt 22 and carries a countercheck or button 43 at its outer end. The button 43 is adapted to engage with a back check 44 after the hammer has been The back check 44 is supported on back-check wire 45 secured adjacent the outer end of the wippen 18 so that it is raised into proper position for checking the backward movement of the hammer when the wippen I8 is lifted by the capstan screw '75 of the key lever. Positioned on the wippen I8 intermediate the wire and the outer end of the wippen, is a bridle wire 43 to which is attached one end of a bridle 41, the other end of which is secured to the hammer butt by means of the rod 42. A spring 48 is provided for returning the hammer to its normal or at-rest position without vibration after a key has been struck. The parts 42, 45, 46, 41 and 43 are arranged as in a standard piano action but are considerably shorter than like parts in such action and contribute to the compactness of my action.

The several rails for supporting the action are mounted upon a plurality of standards, one of which is illustrated in Fig. 1 of the drawing. The standard illustrated comprises a vertically disposed body portion 50 which is pivotally sup ported at its lower end by means of a screw member 5| and which is adjustably secured to the backboard 52 of the piano by means of the threaded rod 53 and the hand nut 54. The standard is provided intermediate its ends with an outwardly extending brace 55 which functions as a rest for the hammer rail 25, the latter of which is pivotally connected to the standard by means of the connecting wires 53. The standard is provided adjacent its lower end with a recess into which is received the body of the action rail 20 and by means of which such rail is supported on the standard. As is shown more clearly in Fig. 2, the action rail 26 has an upper offset portion, the outer face of which is formed to receive the hammer flange 2!, the bottom face of the latter abutting the shoulder formed by the offset upper portion. The upper portion of the rail 20 is so proportioned that when the hammer flange is positioned thereon, the pivotal point of the hammer 22 is disposed in a horizontal direction nearer the pivotal point of the jack 28 than is customary in ordinary upright actions, whereby, when the jack is in its normal at rest position with its upper end engaging in the corner formed by the cushions 26 and 21, the jack is tilted only slightly to the left from the vertical, as viewed in Fig, 1. The ratios of the several lever arms functioning in the operation of the jack and the arc of movement of the point of contact of the jack with the hammer butt cushions under the influence of the stop 32 are so arranged that when the key is depressed and held in its lowermost position using normal playing pressure, the upper end or point of contact of the jack is displaced from its point of contact in the corner between the cushions 25 and 2'! to the right approximately three sixteenths of an inch, or, in degrees, approximately six degrees, so that the jack is tilted slightly to the right, as viewed in Fig. 1, to a position at rest on the right-hand side of a vertical line passed through the axis of the jack. I have found that by arranging the jack with respect to the several connecting parts so it is moved from one side of a vertical line passed through the pivotal point of the jack, through such vertical line to a point on the other side thereof, as a result of the downward movement of the key in the normal playing of the piano, I have been enabled to provide a satisfactory let-off action of the jack for small compact actions of the type with which this invention is concerned. The inner face of such oifset portion of the rail 20 is provided with a felted groove 59 within which is disposed the damper rod 51, the latter being supported in position by the depending members 58 which extend upwardly and are pivotally connected at their upper ends to the projecting ends of the damper rod flanges 60. As is shown in Fig. 2, the flanges 61] are secured in substantially horizontal relation to the top surface of the action rail. The damper rod 57, as is usual, is adapted to engage with the lower end of the damper shank 6| which has supported at its upper end the damper 62. The damper shank 6| is pivotally supported intermediate its ends by the flange 63 which, like the flange 6B, is mounted on the top surface of the rail 20. This manner of supporting the dampers and damper rod enables the ready assemblage and removal of the parts and simplifies the construction of the action rail 20. A spoon E4 is provided on the inner end of the wippen l8 for normal operation of the damper during the playing of the piano.

As a further means for controlling the functioning of the dampers 62, I provide a rod 66,-

having a plurality of upwardly extending standards or supports carrying a hollow silk cord 68 which is threaded through the upper ends of such supports and extends in substantially parallel relation to the rod 5b. small cord made of silk threads braided in a manner well known to the art into a hollow cylindrical form so that it has a very fine bore. The rod 66 normally rests against a pair of felt pads 69 provided on the lower ends of two flange;

members" or supports 10, depending from the outer end portions of the action rail 20. As is shown in Fig, 2, the upper ends of the members H! are practically similar in shape to the wippen flanges l9 and are attached to the action rail in a similar manner, whereas the lower ends thereof are substantially boot-shaped, the felt pads 89 being mounted on the toes thereof. The rod 65 is supported in position against the felt pads 69 by a pair of depending members ll whose upper ends are pivotally connected to the flange members lil whereby the rod 66 may be pivoted inwardly and upwardly, as is shown in Fig. 2. Pivotal movement is imparted to the rod 66 by depressing one of the foot pedals on the piano (not shown) to which it is connected by lifter mechanism of a conventional type and therefore not shown. Each of the damper shanks Bl is provided with a depending wire 12 having at its lower end a head 73 which, as is shown in Fig. 1, normally moves in an arcuate path above the silk cord 88. When the rod 66 has been pivoted inwardly, however, to the position shown in Fig. 2, the silk cord will have been moved into a position where it will be in the path of movement of the head 13. If the damper has been operated, due to the striking of its associated key, so that the head 13 is at its innermost position at the time the silk cord 68 is moved into its path of movement, as shown in dotted lines in Fig. 2, the head 13 will be held against return to its normal position and the damper 62 will be prevented from damping its associated string. Thus, by reason of this arrangement, individual notes or chords may be sustainedduring the playing of the piano. The tension of the silk cord 68 is such that it does not interfere with the noiirnal action of subsequently actuated dampers in the playing of the piano.

t will be observed that by constructing and arranging the several parts of the action and key lever mechanism in the manner above described that the lever arm from the :point. of contact 34 to the pivotal point 33 of the jack 28 .is less than the lever arm from the center of The chord 68 is a;

'force of the spring 30 and bears a 1:5 relationship with the lever arm between such pivotal point and the point of contact at the upper end .of the jack,,arranging the rail 39 so that it performs thedual function of supporting the stops 32 and back stopping the jacks and simplifying construction of the action rail and rearranging the relation of the parts supported thereby, I am enabled to reduce the height of the upright action from 11 /4 inches, which is the height nor- ,mally necessary for the standard upright action,

to that of 7%; inches, without interfering in any way with the requirements imposed by the mod- 1 cm technique with respect to touch, power, resonance, hammer travel, jack action, etc. The

above described arrangement also enables me to incorporate an individual note sustaining mechanism in a small compact upright action unit, which, so far as I am aware, has never before been accomplished.

While the above described construction embodies the preferred form of my invention, it will be apparent that various changes in the specific form shown and disclosed may be made within the scope of the appended claims without departing from the spirit of the invention.

I claim:

1. In a small upright piano, a compactpiano action comprising a wippen, a jack having an outwardly projecting arm pivotally supported on said wippen, a pivoted hammer butt engaging the upper end of said jack, a coiled spring supported j between said wippen and jack arm and adapted r rail, dampers having damper shanks, flange members attached in substantially horizontal position to the upper surface of said action rail and pivotally supporting said damper shanks,

I a second set of flange members attached in substantially horizontal position to the upper surface of said action rail, a damper rod disposed in the groove of said action rail, and supporting members connecting said damper rod with said second set of flange members.

2. In a small upright piano, a compact piano action comprising an action rail recessed on its inner face to provide a longitudinally extending groove, dampers having damper shanks, a wire member depending from each of said damper shanks and having a head at the lower end thereof, flange members attached to said action rail and pivotally supporting said damper shanks, a'second set of flange members attached to said action rail, a damper rod disposed in the groove of said action r-ail, supporting members connecting said damper rod with said second set of flange members, a second rod extending in substantially parallel relation with said damper rod and being provided with a plurality of upstanding posts, a hollow silk cord carried by said posts, a pair of depending supports mounted on said action rail and being provided at their lower ends with a felt cushion against which said second rod normally rests, supporting members pivotally connecting said second rod'to said depending supports and arranged to enable said rod to be pivoted upwardly to move said hollow silk cord into the path of movement of the heads at the lower ends of said Wire members.

3. In a small upright piano having a height substantially less than that of a full-sized upright piano, a compact piano action having a vertical dimension not substantially greater than 7 /4 inches and comprising a wippen pivoted for movement in a vertical plane'and provided on its under surface with a felt pad adapted to be engaged by a capstan screw mounted on the key lever associated with such action, a standard attached to said wippen above the felt pad and extending upwardly therefrom, a jack having an outwardly projecting arm pivotally supported on said standard, a pivoted hammer butt engaging the upper end of said jack, a lateral stop on said hammer butt for the upper end of the jack, a relatively short shank mounted on said hammer butt and supporting a,hammer head, a coiled spring supported between said wippen and jack arm and adapted to normally maintain said jack in engagement with said hammer butt and said lateral stop, and a fixed abutment member disposed above said jaok arm and adapted to engage said arm'and to pivot said jack outwardly away from said lateral stop when said wippen is raised upwardly, the lever arm distance from the point of contact of said jack arm with said abutment member to the pivotal point of said jack in all relative positions of said points during upward and lateral movement of the jack being no longer than the lever arm distance from the center of force of said spring with respect to said jack arm to the pivotal point of said jack, whereby the spring will bias the jack towards said lateral stop before actual disengagement of said points of contact and will thereby insure an immediate complete return of the jack to said lateral stop on each release of each previously depressed key.

FERNANDO A, WESSELL, JR.

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