US2305037A

US2305037A - Piano action

Info

Publication number: US2305037A
Application number: US392876A
Authority: US
Inventors: Schulze Carl
Original assignee: Individual
Current assignee: Individual
Priority date: 1941-05-10
Filing date: 1941-05-10
Publication date: 1942-12-15
Anticipated expiration: 1959-12-15

Description

A Dec. 15, 1942. c. s cHuLzE 2,305,637

` PIANOAACTION Filed May 1o, 1941 Patented Dec. 15, 1942 UNITED STATES PATENT OFFICE 14 Claims.

to the hammer butt.

A further object of the invention is to provide a construction of this type, in which all parts of the action are readily accessible, and can be taken out bodily from the piano as an assembly, leaving the hammer in place.

A further object of the invention is to provide an action which will occupy relatively small space in a front-and-rear direction of the piano. This feature particularly adapts the action for use in spinet type pianos.

A further object of the invention is to produce an action in which the means for adjusting the same, are all located in an accessible position.

A further object of the invention is to provide improved means for imparting the movement from the key to the hammer butt, and for controlling the point of Aset-olf in imparting movement from the jack to the hammer butt.

A further object of the invention is to provide an action which is particularly adapted to impart the driving motion to the hammer, from the keys that are located at or near the ends of the keyboard, and which are necessarily offset at their inner ends.

Further objects of the invention will appear f hereinafter.

aWay.

Fig. 2 is a View similar to Fig. 1, but show-- ing the action in the back-check position, certain parts being broken away.

Fig. 3 is a fragmentary plan view showing a portion of the case of the piano near one end,

and indicating particularly how the invention 55 adapts itself for use with the offset at the end of a piano keyboard. This figure shows certain parts broken away.

Before proceeding to a more detailed description of the invention, it should be stated that the action involves the use of an actuating member or supporting means for the jack; and one of the novel features consists in pivotally supporting this actuator or jack lever above its corresponding key, so that when the jack lever moves forwardly, it will impart the actuating movement from the jack to the butt of the key. One of the points of novelty in the construction, is that the damper is operated by a thrust movement, instead of through the agency of a pull or tension link. On this account, it is possible to remove the jack lever and all the parts carried thereby as an assembly, after the key has been removed. In other words, this jack lever carries the jack, the damper operating means, and also the back check stop, and preferably all of these adjustments of these parts are located on the outer side of the jack lever and below the keyboard, so that they are all readily accessible from the front of the piano, and without necessitating removal of any parts except the front board of the piano when it is necessary to make adjustments.

Another novel feature lies in the means em- 30 ployed for setting off the jack during the forward movement of the hammer, involving the use of resilient means for maintaining the jack in contact with the actuating shoulder on the hammer butt, in combination with means for 35 limiting the movement under the action of this spring, so that when the limit of the forward movement occurs, the set-off of the jack will take place.

The feature of pivotally supporting the jack 40 levers over the inner ends of the keys that actuate them, facilitates the use of this' action With the end keys on the keyboard, which must have the usual offsets or bends at the inner ends of the keys.

Referring more particularly to the parts, l indicates the keyboard on which a plurality of keys such as the key 2, are mounted. These keys are preferably mounted in the usual way on fulcrum pins, such as the pin 3. The key 2 50 that is illustrated, is supposed to be a key located at the end of the keyboard, in which case the key would have an inward offset 4 at its forward end, in which the usual socket 5 would be provided to cooperate with the fulcrum pin.

A lever rail 6 extends longitudinally with the keyboard of the piano and transversely of the keys, as indicated in Fig. 3. This rail 6 operates as a support for supporting means or actuators such as the actuator "I, that correspond to each key, and which carries a jack 8 for engaging the butt 9 of the hammer IE] to impart the striking movement to the hammer. The actuator or jack lever "I has a body II that is disposed in an upright or substantially vertical position just forward of the forward end of the key 2, and it also includes a substantially horizontal extension I2 which is attached pivotally at I3 to a removable anchor block or base I4 that is secured in the forward face of the rail 6 by a removable fastener such as a screw I5. The jack 8 is supported on a pivot pin I6 carried on a bifurcated post I1 secured to the body I I of the jack lever, and the forward end of the jack is in a position to thrust against a rounded and padded shoulder I8 formed on the hammer butt 9. In the position of rest of the action shown in Fig. 1, the end of the jack lies against a padded rest face I9, and with the end face of the jack substantially against the rounded shoulder I8. The jack 8 illustrated, is relatively short, and hence the action of gravity is insignificant in holding the jack on the rest face I9. On this account I prefer to employ resilient means such as a coil spring to maintain this contact, and this spring is located between the forward side of the body II, and a tail arm 2I formed on the jack near its pivotal support.

It is preferable to employ set-off means for the jack when the stroke of the action has progressed to a desired point. This involves the use of means for limiting the swing of the jack on its pivot. For this purpose I prefer to employ a rein or a cord 22, the forward end of which is attached to the end of the tail arm 2I. This cord may be, if desired, guided through a guide opening 23 in the body of the jack lever, the end of the cord being wrapped upon a small spool 24 that is carried rigidly on a rotatable screw 25. In the position of rest, the cord or rein 22 should have some slack in it. This insures that the forward end of the jack can swing down relatively as the jack-lever swings forwardly and upwardly in its movement. By adjusting the length of the rein or cord 22 to any desired length, a set-ofi effect is attained for the jack as soon as the cord becomes taut. This adjusting screw 25 for winding up the cord on the spool 24, is located below the level of the keyboard I, in order to make it accessible from the front when the front board of the piano is taken on,

The hammer butt 9 is provided with a padded back check 26, which cooperates with a padded back check stop 21 to hold the hammer in the back check position if the key is struck and held down.

In order to enable the back check stop 21 to be adjustable, I prefer to make it in the form of a block, the lower end of which is carried on a leaf spring 2S. This block lies adjacent the inner face of the body II, and may be formed with an inclined face 29 against which an adjusting screw thrusts. This adjusting screw, like the adjusting screw 25, is mounted in the jack lever 1, which is preferably formed of light Wood. The body II of the jack lever preferably curves on a large radius toward the hammer butt, so that the lower portion of the body is located about opposite to the back check 26. Beyond this point the body II is preferably formed with a substantially vertical extension or tail 3I, for operating the damper 32 to lift the same off the strings 33. The connection to the damper is not a pull connection, which is commonly used, but is a thrust connection. This makes it unnecessary to have any part connecting the tail-piece 3| to the damper, and this is most advantageous as it enables the jack lever and all its attached parts to be removed as an assembly without necessitating making any disconnection from the damper. This disconnection already exists. The means for operating the damper from the tail-piece 3l involves a push rod or stem 34, the end of which is formed with a cushion head 35 that thrusts against the damper lever 35. The end of the push rod or stem 34 is socketed in an opening 31 through the end of the lever. The other end of the push rod or stem 34, carries a cushion head 38 which cooperates with an adjustable cushioned head 39 mounted in the tail-piece 3I on an adjusting screw 40. Adjacent to the head 38, the stem 34 is guided in a cushioned guide 4I in the lower end of the hammer pivot rail 42. This pivot rail also operates as a damper rail supporting the damper 32, and the damper is provided with a leaf spring 43 pressing the same toward the strings. The action is provided with any suitable counterbalancing means for counterbalancing the key 2 and the jack lever I. If desired, each key 2 may have its own individual counterbalance spring (not illustrated), in the form of a coil or leaf spring between the keyboard and the under side of the key.

The contact between the forward end of the key and the jack lever is preferably effected through the medium of a roller 44 on which rests a padded contact head 45 that is carried on an adjusting screw 46 mounted in the horizontal extension I2 of the jack lever. In a case where the jack lever and assembled parts are very light, as in the present instance, I may provide a small coil spring 4'I that may, if desired, be mounted in the rail 6; and the force of this spring may be adjusted, if desired, by means of an adjusting screw 48, the upper end of which is accessible on the upper face of the rail 5. This spring thrusts with a light force against the upper side of the extension I2 of the lever. In a construction where the jack 8 is of increased length so as to increase the Weight of the jacklever assembly, or in any situation where this assembly has undue weight, it may be counterbalanced by employing a tension spring instead of the compression spring 41, in which case the lower end of the spring would be attached in an eye in the extension I 2, and the upper end would be .swiveled to the lower end of the adjusting screw 48. With this arrangement the weight of the lever assembly could be very nicely counterbala-nced, in which case separate counterbalance springs for the keys would be employed. However, in the present instance, where the jack lever assembly is very light, the compression spring 41 serves the double function of counterbalancing the key, and also maintaining good contact between the roller 44v and the cushioned head 45 for proper depression resistance.

In the position of rest, the hammers all lie against the forward side of the hammer' rail 49, and at this time the lower end of the jack lever 7 lies quite near but not touching the padded face of the jack-lever rest rail 53. This rest rail 53 performs the function of supporting all of the jack-levers when the keys 2 are removed preparatory to lifting out the jack-lever assemblies.

It will be noted that the adjusting

screws

25, 30 kand 40 are all located below the keyboard l, and in a position for easy access when the front board or face board of the piano case has been removed. The adjusting screw 46 for the contact head 45 is `readily accessible from above. Hence all the necessary adjustments for the action can be made without any difficulty.

This action commends itself for many reasons. It is an easy action in operation, avoiding any increased resistance to the movement of the key when the set-off occurs. It also eliminates the necessity for the use of wippens and their associated parts. The relation of the jack and hammer butt to the jack lever, makes the action a quick repeat action, that is to say, it enables the same key to be struck repeatedly with a minimum of time interval.

The overlapping of the key and the jack lever, enables the overall dimension in a front-andrear direction to be greatly reduced, and this particularlyl adapts the action for spinet type pianos.

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 key mounted to rock on a fulcrum pivot, having a body with an offset forward extension, a lever rail extending longitudinally of the keyboard and transversely to the keys, a jack-lever having a body disposed in a substantially upright posiltion forward of the key, having a substantially horizontal extension at its upper end pivotally supported on the lever rail and disposed over the forward end of the key for actuation thereby, a hammer having a butt pivotally supported forward of the jack-lever, and a jack movably supported on the body of the jack-lever and engaging the hammer butt for actuating the same.

`2. In a piano action, the combination of a key mounted to rock on a fulcrum pivot, a keyboard below the key, said key having a body with an offset forward extension, a lever rail extending longitudinally of the keyboard and transversely to the keys, a jack-lever having a body disposed in a substantially upright position forward of the key, having a substantially horizontal extension at its upper end pivotally supported on the lever rail and disposed over the forward end of the key for actuation thereby, a hammer having a butt pivotally supported forward of the jack-lever, a jack pivotally supported on the body of the jack-lever, said hammer butt having a shoulder to be engaged by the end of the jack to impart the striking movement to the hammer, and means located on the rear side of the body of the jack-lever and below the keyboard for adjusting the position of the jack on its pivotal support.

3. In a piano action, the combination of a key mounted to rock on a fulcrum pivot, a keyboard below the key, said key having a body with an offset forward extension, a lever rail extending longitudinally of the keyboard and transversely to the keys, a jack-lever having a body disposed in a substantially upright position forward of the key, having a substantially horizontal extension at its upper end pivotally supported on the lever rail and disposed over the forward end of the key for actuation thereby, a hammer having a butt pivotally supported forward of the jack-lever, a

jack pivotally mounted on the forward side of the jack-lever body, said hammer butt having va shoulder engaging the forward end of the jack to enable the jack to impart the striking movement' to the hammer, a spring associated with the jack to press the same yieldingly toward said shoulder, and means carried on the body of the jack-lever below the level of the keyboard for enabling the position of the jack-lever to be adjusted against the force exerted by said spring.

4. In a piano action, the combination of a key mounted to rock on a fulcrum pivot, a keyboard below the key, said key having a body with an offset forward extension, a lever rail extending longitudinally of the keyboard and transversely to the keys, a jack-lever having a body disposed in a substantially upright position forward of the key, having a substantially horizontal extension at its upper end pivotally supported on the lever rail and disposed over the forward end of the key for actuation thereby, a hammer having a butt pivotally supported forward of the jack-lever, a jack pivotally supported on the body of the jacklever, said hammer butt having a shoulder to be engaged by the end of the jack to impart the striking movement to the hammer, and a flexible rein attached to the jack and guided on the jacklever, with means located on the rear side of the jack-lever and below the keyboard, for adjusting the rein to limit the downward movement of the jack at its free end.

5. In a piano action, the combination of a key mounted to rock on a fulcrum pivot, a keyboard below the key, said key having a body with an offset forward extension, a lever rail extending longitudinally of the keyboard and transversely to the keys, a jack-lever having a body disposed in a substantially upright position forward of the key, having a substantially horizontal extension at its upper end pivotally supported on the lever rail and disposed over the forward end of the key for actuation thereby, a hammer having a butt pivotally supported forward of the jack-lever, a jack pivotally supported on the body of the jacklever, said hammer butt having a shoulder to be engaged by the end of the jack to impart the striking movement to the hammer, said hammer butt also having a rest for the end of the jack adjacent the shoulder, and a spring associated with the jack for holding the same on the rest when the action is in its state of rest.

6. In a piano action, the combination of a key mounted to rock on a fulcrum pivot, a keyboard below the key, said key having a body with an offset forward extension, a lever rail extending longitudinally of the keyboard and transversely to the keys, a jack-lever having a body disposed in a substantially upright position forward of the key, having a substantially ho-rizontal extension at its'upper end pivotally supported on the lever rail and disposed over the forward end of the key for actuation thereby, a hammer having a butt pivotally supported forward of the jack-lever, a jackV pivotally supported on the body of the jacklever, said hammer butt having a shoulder to be engaged by the end of the jack to impart the striking movement to the hammer, said hammer butt also having a rest for the end of the jack adjacent the shoulder, a spring associated with the jack for holding the same on the rest when the action is in its state of rest, and means for limiting the movement of the jack under the action of the spring when the jack-lever moves forward to impart the striking movement to the hammer-butt.

7. In a piano action, the combination of a key mounted to rock on a fulcrum pivot, having a body with an offset forward extension, a lever rail extending longitudinally of the keyboard and transversely to the keys, a jack-lever having a body disposed in a substantially upright position forward of the key, having a substantially horizontal extension at its upper end pivotally supported on the lever rail and disposed over the forward end of the key for actuation thereby, a hammer having a butt pivotally supported forward of the jack-lever, a jack movably supported on the body of the jack-lever and engaging the hammer-butt for actuating the same, a backcheck pad supported on the hammer adjacent its butt, and a back-check stop carried on the lower portion of the body of the jack-lever, with means on the rear side of the jack-lever for adjusting the back-check stop.

8. In a piano action, the combination of a key mounted to rock on a fulcrum pivot, having a body with an oifset forward extension, a lever rail extending longitudinally of the keyboard and transversely to the keys, a jack-lever having a body disposed in a substantially upright position forward of the key, having a substantially horizontal extension at its upper end pivotally supported on the lever rail and disposed over the forward end of the key for actuation thereby,

a hammer having a butt pivotally supported for- Ward of the jack-lever, a jack movably supported on the body of the jack-lever and engaging the hammer butt for actuating the same, a damper lever, means supported below the hammer butt for actuating the damper lever, and means carried by the lower portion of the jack-lever for thrusting against said last-named means to actuate the damper lever when the key is struck.

9. In a piano action, the combination of a key mounted to rock on a fulcrum pivot, a lever rail extending longitudinally of the piano and transversely above the inner ends of the keys, a jacklever having a body disposed in a substantially upright position forward of the key, and having a substantially horizontal extension at its upper end, pivotally supported on the lever rail and disposed over the forward end of the key for actuation thereby, a hammer having a butt pivotally supported forward of the jack-lever, a

jack pivotally mounted on the body of the jack- .f

lever, with its free end lying adjacent the hammer butt and capable of thrusting against the same to impart the driving force to the hammer, and means located on the outer side of the jacklever body for adjusting the relation of the jack i to the hammer butt.

10. In a piano action, the combination of a key mounted to rock on a fulcrum pivot, a lever rail located above the keyboard extending longitudinally of the keyboard and transversely to the key, a jack lever having a body disposed in a substantially upright position forward of the key, having a substantially horizontal extension at its upper end pivotally attached to the lever rail and disposed over the forward end of the key, means for actuating the jack lever by the key, and means for counterbalancing the key and the jack lever.

ll. In a piano action, the combination of a key mounted to rock on a fulcrum pivot, a lever rail extending longitudinally of the keyboard and transversely to the key, a jack-lever having a body disposed in a substantially upright position forward of the key, having a substantially horizontal extension at its upper end pivotally supported on the lever rail and disposed over the forward end of the key for actuation thereby, and resilient means supported on the rail for exerting a force on the jack-lever to attain a counterbalancing effect on the action.

l2. In a piano action, the combination of a pivotally mounted hammer having a butt with an actuating shoulder through which the striking movement can be imparted to the hammer, and having a rest face adjacent to the shoulder, a jack, supporting means for the same constituting a part of the action, pivotally supporting the jack, and movable toward the hammer butt to enable the jack to impart the striking movement to the hammer, a spring urging-the jack in a direction to maintain its forward end in contact with the shoulder, and set-off means including a flexible rein connecting the jack and the said movable support for limiting the swinging movement of the jack on its pivotal support under the action of the spring to deternnne the point of set-01T of the jack when imparting movement to the hammer butt.

13, In a piano action, the combination of a pivotally mounted hammer having a butt with an actuating shoulder through which the striking movement can be imparted to the hammer, and having a rest face adjacent to the shoulder, a pivotally mounted jack with supporting means for the same constituting a part of the action, said supporting means being movable toward the hammer butt to enable the jack to impart the striking movement to the hammer, a spring urging the jack in a direction to maintain its forward end in contact with the shoulder, and operating to hold the end of the jack on the rest face when the action is in a position of rest, and set-off means including a rein attached to the jack, carried on the supporting means and disposed in a, slack condition when the action is in the condition of rest, and operating to limit the swinging movement of the jack on its pivot, and thereby determine the point of set-off of the jack in imparting the driving movement to 'the hammer.

14. In a piano action, the combination of a key mounted to rock on a fulcrum pivot, a lever rail extending longitudinally of the keyboard and transversely to the key, a jack-lever having a body disposed in a substantially upright position forward of the key, having a substantially horizontal extension at its upper end, means accessible from the forward side of the lever rail for pivotally supporting the jack-lever, a pivotally mounted hammer, a jack pivotally mounted on the body of the jack-lever for engaging the hammer butt to actuate the same, a back-check pad for the hammer, and a back-check stop to cooperate therewith carried on the jack-lever below the jack, a damper having a damper lever for actuating the same, means supported below the hammer for operating the damper lever by a thrust movement against the same, and means unattached to the last-named means and carried by the lower end of the jack-lever for operating the damper, all of said parts cooperating to enable the jack-lever and assembled parts carried thereby to be removed as an assembly after the key has been removed.

CARL SCHULZE.