US3545329A

US3545329A - Piano action

Info

Publication number: US3545329A
Application number: US811457A
Authority: US
Inventors: Phillip J Roehrig
Original assignee: Aurora Corp
Current assignee: Aurora Corp
Priority date: 1969-03-28
Filing date: 1969-03-28
Publication date: 1970-12-08
Anticipated expiration: 1987-12-08

Description

United States Patent 1 1 3,545,329

[72] Inventor Phillip J. Roehrig [56] References Cited Kenmore, New York UNITED STATES PATENTS 1 pP 811,457 1,176,655 3/1916 Cross 84/251 1 Flled March 28,1969 1,650,095 11/1927 Rydberg... 84/452 1 Patented kc-8,1970 2,637,238 5/1953 Murdock 84/251 [73] Assignee Aurora Corporation of Illinois Chicago, Illinois Primary Examiner-Richard B. Wilkinson a corporation ofminois Assistant Examiner-Lawrence R. Franklin Attorney-Wolfe, Hubbard, Leydig, Voit & Osann [54] PIANO ACTION 7 Chin, 3 Drawing Figs. ABSTRACT: The wh1p and ack of a piano ectlon are formed from plastic and are molded integrally w1th and mtercon- [52] 11.8. CI. 84/251, nected swingably by a resiliently flexible hinge which is biased 84/236, 84/452 to urge the jack toward a normal rest position. The damper I5 I] Int. Cl (llOc 3/16 lever and supporting flange of the action also are molded of [50] Field of Search 84/236- plastic and are interconnected swingably by a similar 255, 438, 452 resiliently flexible hinge.

PATENTED DEC 8 19m MVSIQTOM Phillip Q4. Qoehgg 44-16 WM 44;); e 0% cyQ-r-romsvw PIANO ACTION BACKGROUND OF THE INVENTION This invention relates to a piano action of the type in which a jack lever pivoted on a whip support swings from a rest position to an operated position to project a swingable hammer lever against a string in re response to the depression of a key. As the hammer approaches the string, a damper lever pivoted on a flange support is swung from a rest position engaging the string to an operated position releasing the string. Piano actions of this general nature are disclosed in U.S. Pat. No. 2,502,861 to Lindroth and U.S. Pat. No. 2,963,934 to Hucke.

SUMMARY OF THE INVENTION The primary aim of the present invention is to provide a piano action of the above type with new and improved pivoted levers and mounting supports which are less costly to manufacture and assemble than the corresponding elements of prior actions of the same general type and which, at the same time, enable depression of the various keys of the action with more nearly the same force and result in a more uniform striking response from key-to-key. In large, the foregoing ends are achieved by molding each lever and its respective support of plastic and by swingably connecting the two with a resiliently flexible hinge molded to the support and lever and biased to urge the latter to its rest position.

In a more detailed sense, the invention resides in the unique construction of the whip and jack as a one-piece plastic unit with an integrally molded plastic hinge swingably connecting the jack to the whip and serving to restore the jack to its rest position when the key is released. The damper lever and flange also are formed as a one-piece plastic unit and also are interconnected by an integrally molded hinge which biases the damper lee lever to its rest position.

Other objects and advantages of the invention will become apparent from the following detailed description when taken in connection with the accompanying drawings.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a fragmentary elevation of a new and improved piano action embodying the novel features of the present invention.

FIG. 2 is a perspective view of the damper lever and flange unit of the action shown'in FIG. 1;

FIG. 3 is a perspective view of the whip and jack unit of the action shown in FIG. 1.

DESCRIPTION OF THE PREFERRED EMBODIMENT As shown in the drawings for purposes of illustration, the invention is embodied in an action (FIG. 1) for a piano of the so-called upright or grand type and having a plurality of hammers 11 (only one being shown) which are projected against vertically disposed strings 13 in response to the actuation of corresponding key mechanisms 14 by the depression of keys (not shown). The keys may be mounted and connected to the key mechanisms in the manner disclosed in the aforementioned I-Iucke patent.

The action proper and the mechanism 14 for transmitting the motion of the keys to the action are mounted on a common bracket 15 (FIG. 1) supporting a main rail 16 on which the hammer 11 is pivoted as indicated at 17. The butt 19 of the hammer is formed with a knuckle 20 which is engaged eccentrically of the hammer pivot 17 by the tip 21 of a generally upright jack lever 23 carried swingably on a support in the form of a whip 24. The latter is disposed in a substantially horizontal position and is supported at its rear end from a flange 25 on the rail 16 so as to swing about a fixed pivot 26.

As the whip 24 is swung upwardly from the rest position shown in FIG. 1, the jack 23 is raised endwise against the knuckle 20 thereby projecting the hammer 11 forwardly against the string 13. During such endwise movement of the jack and as the hammer approaches the string, an arm 27 (FIG. 1) on the jack strikes a regulating button 29 which rocks the jack clockwise relative to the whip and slides the tip 21 of the jack off the knuckle preparatory to back checking of the hammer. Carried on the whip is the usual back check 30 which coacts in a well known manner with a catcher 31 carried by the butt 19. The jack is biased to swing in a counter clockwise direction relative to the whip and, when the latter is returned downwardly upon release of the key, the jack is urged back to its rest position (FIG. 1) in which the tip 21 engages the knuckle 20.

The action 10 also includes a string damper 33 (FIG. 1) carried on the upper end of a damper lever 34 and operable in a conventional manner to engage the string 13 upon release of the key. The damper lever is supported pivotally on a support or flange 35 anchored to the rail 16 and normally is urged counter clockwise relative to the flange to a rest position shown in FIG. 1 in which the damper engages the string. A spoon 36 upstanding from the rear end of the whip 24 engages the lower end of the damper lever and rocks 4 the latter clockwise relative to the flange when the key is depressed, thereby to swing the damper away from the string.

In accordance with the present invention, the jack 23 and the whip 24 are molded of plastic and are connected swingably to one another by a resiliently flexible hinge 40 (FIGS. 1 and 3) which is joined to the jack and the whip during the molding thereof and which is biased to urge the jack toward its rest position. As a result, the need for mechanical pivots between the jack and the whip and the need for a separate spring to restore the jack are eliminated thereby to reduce the cost of manufacturing and assembling the action 10. In addition, the flexible hinge intimately joins the jack and the whip to avoid looseness resulting from the accumulation of manufacturing tolerances in mechanical pivots thereby to cause the jack to effect more positive and uniform striking of the hammer 11.

In the preferred embodiment of the invention, the hinge 40 also is plastic and advantageously is molded integrally with the jack 23 and the whip 24 such that the jack, the whip and the hinge form a one-piece unit. As shown in FIGS. 1 and 3, the hinge is generally U-shaped and includes an upper leg 41 joined to the lower end of the jack and a lower leg 43 joined to the upper side of the whip, the hinge being relatively thin with the legs being spaced apart sufficiently far to accommodate swinging of the jack between its rest and operated positions. The jack, the whip and the hinge preferably are molded of Delrin and by dies which are shaped to form the parts substantially in the relative positions they would assume when the jack is swung just slightly counter clockwise from its rest position with respect to the whip. Thus, the material of the hinge is molded with a preloaded resilient memory toward the rest position and, as a result, automatically urges the jack back to such position and holds the jack against the knuckle 20 when the key is released.

From the foregoing, it will be apparent that the one-piece unit formed by the jack 23, the whip 24 and the hinge'40 can be molded and manufactured at relatively low cost and can be installed quickly and easily in the action 10 as a unitary assembly without need of interconnecting separate pivots and springs. Since the jack is intimately joined to the whip by the integral hinge, looseness caused by mechanical pivots is eliminated and thus the jack engages the knuckle 20 positively and uniformly each time the key is depressed. Moreover, each molded jack and whip unit of the action 10 is exactly identical to every other unit, both as to pivot action and as to spring action, so that each key of the action may be depressed with substantially the same force.

The invention also contemplates molding the damper lever 34 and the supporting flange 35 out of plastic and interconnecting the two with a resiliently flexible plastic hinge 50 (FIGS. 1 and 2) similar to the hinge 40. As shown most clearly in FIG. 2, the hinge 50 is substantially U-shaped and is formed with

legs

51 and 53 which are connected to the damper lever and the flange. The hinge 50 is molded with a preloaded resilient memory effective to bias the damper lever toward its rest position and thus the lever is automatically returned to and held yieldably in such a position by the hinge. Most of the advantages realized by forming the jack 23 and the whip 24 as a molded unit also are attained by the integral construction of the damper lever 34 and flange 35.

I claim:

1. In a piano action having a key mechanism, the combination of, a support, a lever pivoted on said support to swing relative to the latter from a rest position to an operated position in response to actuation of said key mechanism, said support and said lever each being molded of plastic, and a hinge of resiliently flexible plastic molded to and pivotally connecting said lever and said support and biased to urge said lever toward said rest position by virtue of the resiliency of said plastic.

2. A piano action as defined in claim 1 in which said support is a whip and in which said lever is a jack.

3. A piano action as defined in claim 1 in which said support I is a flange and in which said lever is a damper lever.

4. A piano action as defined in claim 1 in which said support, said lever and said hinge are formed as a one-piece unit with the hinge being molded integrally with said support and said lever.

5. A piano action as defined in claim 4 in which said hinge is substantially U-shaped with one leg of the U joined to said support and with the other leg of the U joined to said lever. 7

6. In a piano action having a key mechanism, the combination of, a whip, a jack pivoted on said whip to swing relative to the latter from a rest position to an operated post position in response to actuation of said key mechanism, said whip and said jack each being molded of plastic, and a hinge of resiliently flexible plastic molded integrally with and pivotally connecting said whip and said jack and biased to urge said jack toward said rest position by virtue of the resiliency of said plastic.

7. In a piano action having a key mechanism, the combination of, a flange, a damper lever pivoted on said flange to swing relative to the latter from a rest position to an operated position in response to actuation of said key mechanism, said flange and said damper lever each being molded of plastic, and a hinge of resiliently flexible plastic molded integrally with and pivotally connecting said flange and said damper and biased to urge said damper lever toward said rest position by virtue of the resiliency of said plastic.