US2280982A - Repeat action for grand pianos - Google Patents

Description

A ril 28, 1942. cQscHuLzE 2,280,982

REPEAT-ACTION FOR GRAND PIANQS Filed Feb. 3, 1941 Patented Apr. 28, 1942 r UNITED STATES PATENT OFFICE This invention relates to a piano action, and while features of the invention may be adapted to different types of action, in the present specification the invention has been described as applied to a grand piano action. In the grand type or square piano action, the hammer when at wardly from the hammer butt, and the hammer head is located at a considerable horizontal distance from the pivotal support of the butt so that it is difficult to counterbalance the weight of the hammer head. Furthermore, this position of the hammer tends to cause it to return very rapidly to its normal position from the back check a problem is presented to counterbalance the hammer in such a way that rapid repeat notes can be given. It is one of the objects of this invention to provide a construction which is particularly adapted for enabling rapid repeat notes to be struck. More specifically, the invention concerns means which I employ for counterbalancing the weight of the hammer at the hammer butt in a way that will tend to retard the return of the hammer to its normal position if a key is struck and held down, and then struck again to sound a repeat note. One of the objects of the invention is to provide counterbalancing means which will apply its force in a follow-up manner to the hammer butt, and thereby give a superior effect to an ordinary counterbalancing spring applied to the hammer butt, which must extend itself as the hammer moves forwardly, the result of the extension of the spring being that it becomes relatively weaker as a counterbalance spring in proportion to the degree of its extension. In accordance with my invention the counterbalancing spring operates through a counterbalancing jack which is mounted on the actuating lever that actuates the 1 driving jack that drives the hammer in its stroke, thereby enabling the spring to exert a more or less constant counterbalancing effect even when the hammer is in its advanced, backcheck position.

A further object of the invention is to provide a piano action having theseadvantageous characteristics, composed of few parts and capable of nice adjustment particularly as regards the degree of pressure or terbalancing jack.

Further objects hereinafter.

The invention consists in the novel parts. and combination of parts to be described hereinafter,.

of the invention will appear thrust exerted by the counall of which contribute to produce an efficient repeat action for grand piano.

A preferred embodiment of the invention is described in the following specification, while the broad scope of the invention is pointed out in the appended claims.

In the drawing:

Fig 1 is a vertical section through a piano case, certain parts being broken away, and illustrating the essential parts of a piano action embodying my invention. In this view the action is shown in a position of rest.

Fig. 2 is a view similar to Fig. 1, but shows the action in its back-check position.

Before proceeding to a more detailed description of this piano action, it should be stated that in practicing the invention, an actuating lever is provided carrying a driving jack that cooperates with the driving shoulder on the butt of the hammer. In addition to this, a resiliently pressed pivotal support for the hammer butt. In this way, as the actuating lever swings forwardly when the While the actuating lever referred to in the above paragraph, may be actuated by the piano key, in the simple construction illustrated in the drawing and now to be described, the actuating lever is the rear end of the regular or usual piano key.

' The key 9 which, of course, operates as an ac- 'tuating lever for the action,

supports a regular jack H which is pivotally supported at l2 on a post B or posts on the upper side of the key 9. I prefer, however, not to support the post l3 directly on the body of the key 9, but upon a splint 9a which is virtually a part of the key but connected to the same by any suitable means such as a screw 14. This construction is advantageous because it gives a ready vertical adjustment for the jack II, and also for the counterbalancing jack that will be presently described. This adjustment is made possible because the splint or tongue 9a adjacent its root I5, is cut down to a thin neck 16 which will readily flex, and under the free end I! adjusting means is provided, enabling this free end to be adjusted up or down. The resiliency of the splint 9a at the neck 16, tends to press the splint down toward the body of the key, and this enables a very simple adjusting means to be employed, consisting of one or more lifts or lift means I8 that may be put in position in the gap or throat 19 between the splint 9a and the body of the key.

This free end i! of the splint 9a constitutes a base means for resilient means to maintain the counterbalancing jack pressed against the butt 4 of the hammer. In the present instance, for accomplishing my objects, I provide a leaf spring 20 which is disposed in an inclined position with its flat faces constituting its upper and lower sides. The relatively fixed end of this spring may be held tight in a transverse inclined cut 2| formed in the upper face of the base means H. The upper end of the spring 20 is preferably provided with a block 22 that affords means for effecting a pivotal connection 23 to the lower end of a counterbalancing jack 24, the upper end of which thrusts against the under side of the butt 4 at a bearing point that is located between the pivot of the butt and the driving shoulder 25, which is engaged by the toe of the jack II. In order to provide a slightly flexible connection between the upper end of the counterbalancing jack 24 and the bearing point for the jack on the hammer butt, I prefer to provide a socket 26 on the under face of the butt 4, and I prefer to taper the upper end of the counterbalancing jack 24 and shape it sothat its upper end terminates in a pintle or pin 21 that is of considerably smaller diameter than the socket 26, thereby permitting free movement at this point. The upper end of the counterbalancing jack adjacent the pintle, is preferably in the form of a tapered nose 28 with a slight shoulder at its upper end that thrusts against the pad 29 secured to the under side of the butt 4, including the edge of the socket.

This thrust and contact is preferably maintained throughout the entire movement of the action. The jack I I is provided with the usual coil spring 38a under its heel 30, that presses the toe of the jack up against the driving shoulder 25. This driving shoulder 25, of course, is padded and may have any desired form, but in the present instance it ,is shown. as an inclined shoulder that intersects with a substantially vertical shoulder 250:. When the action is at rest the spring 30a holds the toe of the jack up against this vertical rest shoulder 25a, that is to say, in the angle between this shoulder and the inclined shoulder 25.

When the key 9 is struck, the heel 30 of the jack encounters a set-off or stop 3| that swings the upper end of the jack out of engagement with the shoulder 25 before the hammer 5 reaches the string. If the key is held down, the hammer of course, will return to its back-check position shown in Fig. 2. Now when a repeat note is struck, the release of the key for striking the repeat note will, of course, permit the back-check pad 1 to descend, and this, of course, would take it out of the path of the back-check tail 32 of the hammer head. The hammer would then be accelerated downwardly by gravity, and in the absence of my counterbalancing jack 24, this descent would be quite rapid and would not allow time for the toe of the jack H to get back under the shoulder 25 for striking a repeat note. However, my counterbalancing jack through the agency of-the leaf spring 20 that supports it, will exert a resistance that retards the fall of the hammer head 2, and this of course, allows time for the jack II to get down under the shoulder 25 to strike the repeat note or notes.

Attention is called to the fact that my improvement involves the basing of the counterbalancing jack spring 20 on the key 9 and between the location of the hammer butt and the fulcrum pin ID at which the key 9 rocks. For this reason as the hammer butt 4 swings upwardly, the block 22 that carries the counterbalancing jack 24, will have a considerable rise as it would move upwardly on a radius from the rocking point at the base of the pin it up to the location of the conical tip'28.

As pointed out above, where it is necessary to makeany adjustment in the height of this block 22, this can be accomplished by using thicker or thinner lifts l8 under the free end of the splint 9a. Some of these lifts may be of wood or rigid material, but it is advisable to have one or more of these lifts composed of soft pad material such as indicated in the drawing.

Many other embodiments of the invention may be resorted to without departing from the spirit of the invention.

What I claim is:

1. In a piano action, the combination of a hammer having a shank with a butt, a pivotal support for the'hammer butt, said butt having a driving shoulder, an actuating lever, a driving jack pivotally supported on the actuating lever and engaging the driving shoulder for swinging the hammer forward, resilient means for pressing the driving jack, into contact with the driving shoulder, set-off means cooperating with the'jack' to move the same out of contact with the shoulder during the forward movement of the hammer, a resilient.counterbalancing member supported on the actuating lever, a counterbalancing jack jointed thereto, engaging the hammer butt and maintaining contact substantially at all times with the same at a substantially fixed point on the. hammer butt located between the driving shoulder and the pivotal support of the hammer butt, said counterbalancing jack operating to retard the return of the hammer and thereby allow time after the actuating lever has been moved to, and held in, its extreme position, for the driving jack to re-engage with the driving shoulder, for strikinga repeat note.

2. In a piano action, hammer having a shank with a butt, a pivotal support for the hammer butt, said butt having a driving shoulder, an actuating lever, a driving jack pivotally supported on the actuating lever and engaging the driving shoulder for swinging the hammer forward, resilientmeans for pressthe combination of a ing the driving jack into contact with the driving shoulder, set-off means cooperating with the jack to move the same out of contact with the shoulder during the forward movement of the hammer, said butt having a bearing point located be tween the driving shoulder and the hammers pivot, a counterbalancing jack for the hammer having a flexible joint supported on the actuating lever, having a connection to, and thrusting against, the hammer butt at said bearing point, said counterbalancing jack operating to retard the return of the hammer and thereby allow time after the actuating lever has been moved to, and held in, its extreme position, for the driving jack to re-engage with the drivin shoulder, for striking a repeat note.

3. In a piano action, the combination of a hammer having a shank with a butt, a pivotal support for the hammer butt, said butt having a driving shoulder, an actuating lever, a driving jack pivotally supported on the actuating lever and engaging the driving shoulder for swinging the hammer forward, resilient means for pressing the driving jack into contact with the driving shoulder, set-off means cooperating with the jack to move the same out of contact with the shoulder during the forward movement of the hammer, a leaf-spring supported at one end on the said actuating lever and having its free end located adjacent the hammer butt, a counterbalancing jack pivotally supported on the free end of the leaf spring, said hammer butt having a hearing point engaging the end of the countel-balancing jack and located between the driving shoulder and the pivot point of the hammer butt.

4, In a piano action, the combination of a hammer having a shank with a butt, a pivotal support for the hammer butt, said butt having a driving shoulder, an actuating lever, a driving jack pivotally supported on the actuating lever and engaging the driving shoulder for swinging the hammer forward, resilient means for pressing the driving jack into contact with the driving shoulder, set-off means cooperating with the jack to move the same out of contact with the shoulder during the forward movement of the hammer, a leaf-spring supported at one end on the said actuating lever and having its free end located adjacent the hammer butt, a counterbalancing jack pivotally supported on the free end of the leaf spring, said hammer butt having a bearing point engaging the end of the counterbalancing jack and located between the driving shoulder and the pivot point of the hammer butt, the hammer butt having a socket at the said hearing point, and-the counterbalancing jack having a pin received loosely in the said socket to maintain the end of the counterbalancing jack in contact with the hammer butt as it swings forward.

5. In a piano action, the combination of a hammer having a shank with a butt, a pivotal support for the hammer butt, said butt having a driving shoulder, an actuating lever, a driving jack pivotally supported on the actuating lever and engaging the driving shoulder for swinging the hammer forward, resilient means for pressing the driving jack into contact with the dr iy ing shoulder, set-off means cooperating with the jack to move the same out of contact with the shoulder during the forward movement of the hammer, a counterbalancing leaf spring having its free end located near the hammer butt carrying the relatively fixed end of the leaf spring and supported on the actuating lever so that the base means is adjustable on the actuating lever to regulate the position of the free end of the leaf spring, and a counterbalancing jack supported on the free end of the counterbalancing leaf spring and thrusting against the hammer butt between its pivotal support and the driving shoulder and operating to retard the return of the hammer, and thereby facilitate the playing of quick repeat notes.

6. In a piano action, the combination of a hammer having a shank with a butt, a pivotal support for the hammer butt, said butt having a driving shoulder, an actuating lever, a driving jack pivotally supported on the actuating lever and engaging the driving shoulder for swinging the hammer forward, resilient means for pressing the driving jack into contact with the driving shoulder, set-off means cooperating with the jack to move the same out of contact with the shoulder during a forward movement of the hammer, a splint connected with the actuating lever adjacent the free end of the lever, and extending under and past the hammer butt, lift means under the free end of the splint for adjusting the same to any desired position, a counterbalancing leaf-spring connected to the free end of the splint, having its own free end lying adjacent the hammer butt, and a counterbalancing jack having a pivotal connection supporting the same on the free end of the counterbalancing spring and thrusting against the hammer butt between its pivotal support and the driving shoulder, and operating to retard the return of the hammer to facilitate the playing of quick repeat notes.

7. In a piano action, the combination of a hammer having a shank with a butt, a pivotal support for the hammer butt, said butt having a driving shoulder, a piano key having its fulcrum forward of the location of the hammer butt and with its rear end extending rearwardly under the hammer, a driving jack pivotally supported on the actuating lever and engaging the driving shoulder for swinging the hammer forward, resilient means for pressing the driving jack into contact with the driving shoulder, set-01f means cooperating with the driving jack to move the same out of contact with the shoulder during the forward movement of the hammer, a splint supported on the rear end of the key and extending under and past the hammer butt, means associated with the free end of the splint for adjusting the same, a leaf-spring mounted on the free end of the splint with its own free end lying adjacent to the hammer butt, said hammer butt having a socket formed therein between the pivotal support of the hammer butt and the driving shoulder, a counterbalancing jack pivotally supported on the free end of the leaf-spring and having its end received in the said socket, said counterbalancing jack operating to retard the return of the hammer and thereby facilitate the striking of rapid repeat notes.

CARL SCHULZE.

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