US2524835A - Action for upright pianos - Google Patents

Description

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N. A. RINGHOLZ 2,524,335

ACTION FOR UPRIGHT 'PIANOS Filed Jan. 21, 1948 INVENTOR.

#0116531 A. KING/ 0L2 rmzwsvg Patented Oct. 10, 1950 ACTION FOR UPRIGHT PIANOS Norbert A. Ringholz, Columbus, Ga., assignor of one-half to J. Quinton Davidson, Columbus,

Application January 21, 1948, Serial No. 3,407

I 3 Claims.

The present invention relates to improvements in actions for upright pianosand has for an object to provide in an upright piano action similar characteristics in response and repetition to those had in grand piano actions with consequent efficiency in performance techniques and in tonal reproductions.

Another object of the invention is to provide an improved upright piano action simulating closely the grand piano action to enable the same results to be had in the upright action as are provided in the grand piano action whereby great artistic performers on the pianoforte may be enabled to work their art upon the upright piano keyboard with the same efficiency and the same substantial results as are had now only in grand pianos.

A further object of the invention resides in providing an improved upright piano action in which the back check as presently known is eliminated and an improved back checking device substituted of fewer parts and of simplified operation in which the hammer mechanism is back checked in an improved manner which enable repetition of the action to occur in any angular position of the hammer mechanism short of the tripped position and with undiminished effeet as compared with the hammer momentum acquired from the rest or origin position.

A still further object of the invention is to provide an improved upright piano action in which an improved and simplified back checking device is incorporated, eliminating not only the conventional back stop and check but also the bridle wire and bridle strap which were formerly depended on to assist in the return of the ham mer to its origin or rest position.

The invention further contemplates an improved upright piano action with an improved back check device which will eliminate back check blocking and maintain the hammer mechanism at all times free for repetitive action.

With the foregoing and other objects in view, the invention will he more fully described hereinafter, and will be more particularly pointed out in the claims appended hereto. 7

In the drawings, wherein like symbols refer to like or corresponding parts throughout the several views,

Figure l is a side elevational view of an improved upright piano action constructed in accordance with the present invention with the parts shown in the origin or rest position,

Figure 2 is a similar view showing the parts in an intermediate position,

Figure 3 is also a side elevational view showing the hammer mechanism thrown to its farthest impelled position with the release of the jack from the hammer butt,

Figure 4 is a similar view showing the parts in the fully tripped position,

Figure 5 is a perspective View, taken on an enlarged scale, of a form of back check and repetition spring employed; and,

Figure 6 is a similar View showing a modified form of spring.

Referring more particularly to the drawings, 10 designates a key of a piano action and l! its key-frame with the usual front rail pin and punching indicated at l2.

The key is mounted as usual upon the balance rail pin and punching l3 and carries at its rear end portion an upstanding capstan screw M for engaging in the customary manner against the felted under surface of the wippen 15. The wippen is pivoted upon the wippen center pin I! in the wippen flange I 6.

The wippen carries a jack flange I8 in which the lower end of a jack is is pivoted upon the jack center pin 20. The jack knuckle 21 projects as usual from the lower end thereof and is engaged by the jack spring 22 interposed between the knuckle 2| and the wippen l5.

The usual regulating rail 23 carries a regulating button 24 by means of a regulating screw 25 with the button positioned to be engaged by the jack knuckle 2| in the elevated position of the wippen and jack.

The hammer butt 26 is mounted as usual pivotally upon the hammer butt center pin 21 carried by the hammer butt flange 28. The hammer shank 29 carries the hammer in the usual way in relation to the particular string SI for which the hammer is designed. In the origin or rest position the hammer shank 29 lies against the hammer rail 32.

-A conventional spring rail 33 carries the spring rail spring 34 at one end with the other end of the spring engaging the hammer butt 25 for the purpose of assisting in restoring the hammer mechanism to the back check position or to the origin or rest position with the hammer shank Z9 engaging the hammer rail 32.

The hammer butt 25 has the usual hammer butt felt 38 and also the usual buckskin faced hammer butt shoulder 39 and adjoining inclined surface 40.

In accordance with the invention the hammer butt 26 carries a back stop shank 35 through which threadedly engages a back stop regulating 3 screw 3'! carrying a back stop regulating button 36.

The jack i9 is conventional except for the fact that a substantial clearance is left in the origin or rest position of the parts between the upper end of the jack l9 and the hammer butt shoulder 39. In present constructions, when properly regulated, there is approximately -inch clearance between the shoulder 39 and the upper end of the jack 19 so that when the piano key [0 is depressed at the keyboard the jack substantially immediately engages the shoulder to rotate the hammer butt.

However in accordance with the present invention I provide a substantial space between the upper end of the jack l9 and the hammer butt shoulder 39. to prevent the jack from engaging the shoulder 39 at least during the initial movement of the hammer mechanism.

The upper end of the jack [3 carries a back check and repetition spring by means of a substantially straight spring shank 4! extending along the upper portion of the front edge of the jack and being secured at its lower end to the jack by an anchor fastening 42, such as a screw or the like. At the upper end of this shank 41 just above the upper end of the jack IS the spring is shaped to provide a knuckle 43 designed to engage the inclined surface 43 of the hammer butt 26. In one form of the invention this knuckle may be conveniently formed by bending the spring wire into a helix of a suitable number of convolutions in which the axis is substantially horizontal and parallel to the axis of the center pin 2! about which the hammer mechanism rotates. The helical form of the knuckle has advantages in that its surface contacting the inclined surface 46 is curved or rounded and therefore readily slides over the same. The helix also is resilient in its own convolutions and resilient in its connection with the shank so that it may yield forwardly at least to a small degree.

A spring bow 44 extends off the knuckle 43 with its convex side presented beneath the back stop regulating button 36. of the spring wire may be upwardly and inwardly turned as indicated at 45 to impart rigidity to the unsupported end of the spring.

In operation, when a key In is depressed at the keyboard it will result in the usual manner in the elevation of the inner portion of the key and through the capstan screw [4 and wippen IS the connected jack [9 will also be elevated.

From an inspection of Figure 1, it will be clear that contrary to prior practice the upper end of the jack l9 does not initially contact the hammer butt shoulder 39 but is spaced a substantial distance therefrom. However the spring knuckle 43 engages the hammer inclined surface 43 in the origin or rest position of the hammer butt 26, so that in the initial elevating movement of the jack [9 the spring knuckle 43 will transmit the upward vertical thrust of the jack i9 to the hammer butt 26 and the hammer butt 26 will be initially rotated by this thrust action.

It will be noted from Figure 1 that the spring bow 44 engages the back stop regulating button 36 in the origin or rest position in such manner as to maintain the spring knuckle 43 on the inclined surface 4%, and prevents the knuckle 43 from idly sliding relatively along the surface 46. In other words it compels the transmission of thrust from the jack 19 through the spring knuckle .3 and to the hammer butt 26 without any appreciable lost motion.

The outer free end Also the spring bow 44 reacting against the back stop button 36 maintains the jack 19 against swinging so far forward about its pivotal connection with the wippen [5 as to cause the upper end of the jack [9 to get out of alignment with the hammer butt shoulder 39 because, as shown in Figure 2, the upper end of the jack [9 does in fact engage beneath the hammer butt shoulder 39 after the hammer butt 26 has rotated through an initial arc of movement. Also the spring bow 44 engaging beneath the button 36, which is felt faced, at the same time exerts a thrust on the hammer butt 26 tending to rotate the same. By adjusting the screw 3! in the shank 35 this button 36 may be moved up and down relatively to the spring bow 44 for increasing or lessening the tension and the felt face of the button 36 offers a frictional surface to the spring bow 44.

Due to the inclination of the jack l9 and the origin position of the hammer butt 26 which is usual in upright pianos after the hammer butt 26 has rotated through a slight angle and the jack l9 raised correspondingly consequent upon key action, the clearance between the upper end of the jack l9 and the hammer butt shoulder 39 will have been taken up so that, as shown in Figure 2, the jack will engage beneath the hammer shoulder 39 and act to impel the hammer mechanism on its striking motion which has already been initially begun as indicated in Figure l. The contact of the spring bow 44 on the back stop regulating button 36 will continue to contribute to this motion.

This action will continue until the trip position is reached, as shown in Figure 3. In accordance with ordinary practice from this trip position the hammer mechanism will travel by momentum the remaining distance into contact with the string 3 l. The jack knuckle 2| will have engaged its regulatin button 24 so as to require the upper end of the jack l9 to swing away from the hammer butt 26, and the back stop regulating button 36 will lift off the spring bow 44 as the hammer moves into impact with the string, as shown in Figure 4. Figure 4 shows the full trip position of the parts.

The hammer mechanism will spring back from this impact with the string in the usual manner aided by the spring rail spring 34. I prefer to increase the load of this spring rail spring 34 slightly to compensate for the elimination of the conventional back stop, back check wire, back check, bridle Wire and bridle strap. The increasin of the spring tension will give the same touch at the key which would otherwise be disturbed due to the elimination of the weight in the parts discarded.

After the momentum and tripping operations, the hammer mechanism will rebound to osition shown in Figure 3 with the back stop ating button 36 impinging against the in. new which cushions the return movement and slows the same down. The spring bow 44 is subject to resilient deflection owing to the fact that it is carried by the knuckle which is in the form of a spring helix and the load of this spring action may be adjusted and regulated to give the desired back stop action.

As the key is released and the wippen 15 drops the jack knuckle 2i will be withdrawn downwardly from its regulating button 24 whereby the jack spring 22 will again expand and swing the jack rearwardly about its center pin so that the parts are restored to the original initial position with the spring knuckle 43 reengaging the hammer inclined surface 40 and with the spring how 44 moving to the left beneath the back stop regulating button 36. The parts are therefore automatically restored to the position of Figure 1 which is the position of origin or rest where the same are in readiness for subsequent actuation.

The reason for creating the clearance between the jack and shoulder of the hammer butt is to enable the jack to move backwardly to its initial position without interference from the hammer butt irrespective of the position of the hammer butt. Heretofore, in prior constructions where the fit between the jack and hammer butt was a very close one the hammer butt, particularly in its rest or origin position would block the return of the jack to initial or origin position and thus would create what is known in the art as sticky jacks- The result of eliminating sticky jacks is to secure in the new device quicker repetition. This clearance between the jack and the shoulder of the hammer butt also prevents back check blocking. i

The clearance between the upper end of the jack l9 and the hammer butt 26 may be produced not only by the replacement of the normal jack with a jack shorter in length but the clearance may also be had by the adjustment of the capstan screw 14 to lower the jack and wippen relatively to the hammer butt so that it is to be distinctively understood that the conventional jack may be retained in the piano action and the beneficial results of the invention may be secured by attaching the improved back check and repetition spring to the upper end of the jack and by adding the back stop regulating button 36 and its regulating screw 31. In other words the invention more particularly resides in the spring and the back stop regulating button 36. The conventional jack might also be left in place and trimmed or filed down as to its upper edge to leave the desired clearance; or the conventional jack could be left untouched and the hammer butt buckskin could be shaved down to give this clearance.

In referring more particularly to Figure 6, a modified form of back check and repetition spring is illustrated made from flat spring, leaf material rather than from the round. cross section material of spring shown in Figures 1 to 5 inclusive. This flat spring comprises a shank M a spring knuckle 43 and a spring bow 44 It will be noted-that while the spring knuckle 43 is not in the form of a helix still it is so crimped or bent that it will connect the spring bow Ml with the shank M as to provide a resilient support for the bow l l and permit of some relative resilient movement between the bow 44 and its shank 4|.

It will be understood that I have illustrated and described the invention with reference to only a single key of the piano keyboard, but that in actual practice all of the eighty-eight keys or other complement of keys on a standard keyboard will be provided with individual jack, hammer and back stop mechanisms for individual operation in accordance with well known principles in a piano action construction and operation.

It will also be understood that the invention is applicable to existing forms of upright piano actions by simply removing from the existing constructions the back stop, the back check, the back check wire, the bridle wire and the bridle strap and, after adjusting the capstan screw to lower the jack, mounting on the jack a back check and repetition spring according to the present invention and by tapping the hammer butt shank 28 with a screw opening to receive the backstop regulating screw 3l carrying the back stop regulating button 36. The only other change required is that of substituting a slightly stronger spring rail spring 3 5 or by strengthening the incumbent'spring 34 as by rebending or reshaping the same in a manner well known to those skilled in this art. These parts can be introduced at small expense in materials and labor. Where desired a shortened jack may be substituted for the incumbent jack.

Although I have disclosed herein the best form of the invention known to me at this time, I reserve the right to all such modifications and changes as may come within the scope of the following claims.

What I claim is:

1. For use with a piano action for upright pianos having the usual hammer butt with shoulder and inclined surface and shank, the usually key and wippen, and a jack shorter than the conventional jack and pivoted to the wippen, a back check and repetition device comprising a spring adapted to be carried by the jack at the free end portion thereof and having a knuckle adapted to engage the inclined surface of the I hammer butt, and also having a spring bow extending off said knuckle, and a back sto button adapted to be carried by the shank in position to engage the spring bow, said spring having a resilient shank extending along the upper portion of the jack and adapted to be afiixed thereto at its lower end portion with the knuckle extending just above the upper end of the jack and with the spring bow presented on its convex side to the button.

2. A back check and repetition device as claimed in claim 1 characterized by the fact that the spring is a flat leaf spring having a portion crimped upwardly to form the knuckle and to provide a spring support for the bow.

3. For use with a piano action for upright pianos having the usual hammer butt with shoulder and inclined surface and shank, and the usual key and wippen, a back check and repetition device comprising a jack pivoted to the wippen and being slightly shorter than the conventional jack to provide a substantial clearance between the upper end of the jack and the shoulder of the hammer butt, a spring adapted to be carried b said jack and having a knuckle adapted to engage the inclined surface of the hammer butt, a spring bow extending off said knuckle, and a back stop button adapted tobe carried by the shank in position to engage the spring bowf' NORBERT A. RINGI-IOLZ.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 270,322 Mallinson Jan. 9, 1883 827,952 Battalia Aug. 7, 1906 886,341 Beckwith May 5, 1908 1,586,547 Eastwood June 1, 1926

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