US2554129A - Piano action - Google Patents

Description

C. F. STEIN PIANO ACTION May 22, 1951 4 Sheets-Sheet 1 Filed May 28, 1947 c. F. STEIN I PIANO ACTION May 22, 1951 4 Sheets-Sheet 2 Filed May 28, 1947 v INVENTOR. Charlesfieaerztfi 521 23,

4 Sheets-Sheet 3 mmvroga. Mama?) Kean C. F. STEIN PIANO ACTION May 22, 1951 Filed May 28, 1947 Patented May 22, 1951 PIANO ACTION Charles Frederick Stein, Ivoryton, Conn., assignor to Pratt, Read and Company, Inc., Ivoryton, Conn., a corporation of Connecticut Application May 28, 1947, Serial No. 750,932

3 Claims.

This invention relates generally to piano actions and more particularly to a relatively simple action adapted for use with a piano having horizontally positioned strings.

In the prior art various attempts have been made to provide piano actions having down striking hammers for use in pianos having horizontal strings. These attempts have resulted in action structures which are relatively complicated and which are hard to get at to repair or adjust. Further, such actions have not been entirely satisfactory to provide a hammer which swings freely to strike a piano string with the required impetus and is then checked so that it does not bounce to again touch the string. It is also important that the action return to its position for operation quickly as required when fast passages are being played. In prior actions of this type, the response of the action to the touch of the person playing has been somewhat different than in standard upright and grand pianos making it difficult for a person accustomed to playing standard pianos to get the desired effects.

It is, therefore, an object of the present invention to provide an improved action for a horizontal piano which is of simple construction and which may be easily adjusted.

It is a further object of the present invention to provide an action for a horizontal piano having down striking hammers in which the characteristics of the action are substantially the same as that of accepted upright and grand piano actions.

A feature of the present invention is the provision of a simple piano action which requires a minimum of space and which is suitable for use in small pianos such as pianos adapted for portable use.

Another feature of the present invention is the provision of a piano key and action assembly in which adjustable spring means are provided for controlling the movement of the keys and hammers thereof.

A further feature of the present invention is the provision of a piano action including a hammer with a hammer butt which is operatively connected to the end of a piano key and which is spring biased to the normal position for operation by the key.

A still further feature of this invention is the provision of a piano hammer and a spring connected to the butt thereof which is arranged to apply the same force to restore the hammer to the normal position for operation regardless of the position of the hammer.

Further objects, features and advantages will be apparent from a consideration of the following description taken in connection with the accompanying drawings in which:

Fig. 1 is a perspective view of a piano showing the key and action assembly in accordance with the invention in position in the piano;

Fig. 2 is a cross-sectional view illustrating the key and action assembly;

Fig. 3 shows the key and action assembly of Fig. 2 in operative position;

Figs. 4 and 5 are detail views of springs used in the piano action;

Figs. 6 and 7 illustrate the normal and operative positions of a modified piano action; and

Figs. 8 and 9 illustrate the normal and operative positions of a still further piano action. 7

In practicing the invention, there is provided a piano action and key assembly including a key frame on which the keys are supported and a fixed rail structure for supporting the piano action. The piano action includes hammers having hammer butts pivotally supported on the fixed rail structure and adapted to be operated by extensions provided on the piano keys. Individual springs are secured to the rail structure for biasing the keys to their normal positions. Adjustable means are associated with the springs for changing the tension thereof so that the pressure required to operate the key can be adjusted. Springs are also provided for holding the hammers in the normal positions for operation, these springs also being adjustable and being so arranged that the force exerted thereby on the hammer is substantially constant for all positions of the hammer. A damper is also provided which is operatively connected to the butt of the hammer so that it is withdrawn from the spring when the action is operated.

Referring now to the drawings, in Fig. 1 there is illustrated a small horizontal piano [0 which is styled to correspond to a spinet desk. A string chassis II is provided in the piano including a frame which supports the strings and a sounding board. This structure is disclosed in United States Patent No. 2,505,806, dated May 2, 1950. Supported on the string chassis II and extending substantially over the entire area thereof is a key and action assembly l2 including a plurality of keys l3 and actions M in accordance with the invention. The piano also includes a lyre structure l5 including pedals It for changing the expression of the action as will be further described. A music rack I! is supported on a frame is extending across the rear portion of the keys IS. The case for the piano includes a hinged top I9 which can be opened as shown to provide increased volume from the piano and provide access to the key and action assembly. The music rack is pivotally supported so that it can be turned forward and the cover l9 completely close the case.

Although the piano. action in accordance with the invention may be used in any piano having horizontally positioned strings, it is particularly adaptable for use in a small piano such as dis-.-

closed in Fig. 1. In pianos actually constructed which include 64 keys, the entire piano may be only 38 inches wide and 23inches deepand the operating structure of the-piano can all be included in a case having a vertical dimension of approximately '7 inches. A singlemetalframe may be provided for supporting the strings and other operating components of the piano. When using a frame made of; a light metal having a high tensile. strength,. such as an aluminum or magnesium alloy, the. overall weight. of a piano as illustrated is only about eighty pounds.

Such an operating structure is obviously very easily portable and can be provided in a portable carryingcase adapted to be carried by a person in the same manner'as a large suitcase. Such a portable ,piano is disclosed and claimed in my copending openings through which the bridges extend. Ad-

ditional openings may be provided in the'frame at points, where the strain produced therein by the strings permits, to reduce the weight of the frame. For supporting the keys there is provided a key frame. which, is secured to the metal frame 29 as bystrips 3|. The strip 3| atthe front of the frame is shown in Fig. 2 and similar strips are provided at the-sides, of frame 29. The

.key frame includes the standard key mountings having pins 32 therein for guiding the keys l3.

The fixed railstructure includes a plurality of rails 35, 36, 31, 3B and 39, therails being secured to the metal frame 20 as by brackets shown'in Fig. 1. The rail 35 is used for mounting a plural- ,ity of springs 4| which are arranged to hold the keys I3 in the normal position for the playing.

A detailed view showing the configuration of the spring 4| is included as Fig. 4. Each spring 4| is held in position on the rail: 35'by a screw 42 which passes through a washer 43 and loop 44 in the spring and is threaded into the rail. Theend of the-spring 4| rests on a ridge 35a and by adjusting the screw 42 the tensionof the spring 4| is changed. This changes the force required to depress the piano key I3.

The piano action includes a hammer 45 having ahead 46 and a butt portion 41 which is pivotally s pported onthe rail 36. The hammer butt 4'! includes an extension 48 having a screw 49 adjustably positioned therein. Each of the keys I3 includes a rear extension 50 which is arranged to engage the head of the screw 49 toprovide a direct connection between the key and hammer. Felt Or other resilientmaterial may be provided onthe extension 50 of the key which engages the be changed by screw 52 which is adjustably positioned in the rail 31. The spring is positioned in a slot in the rail 38 which forms a guide therefor as illustrated at 53 in Fig. 1.

The piano action also includes a plurality of dampers 55 which are pivotally mounted on a.

fixedrail 39 and include heads 56 made of resilient material which normally bear against the piano strings, 23. For raising the dampers from the strings, hooks 51 are provided which are connected to flexible cord 58 anchored in the hammer butt 41. As the hammer butt is rotated by the extension 50 of the key, the flexible cord and hook, 51 cause the damper to be raised and the head thereof removed from the string. Provi sions are also made for raising the dampers by the foot pedal mechanism. This arrangement includes a movable rail 60 pivotally supported on the fixed rail 39 and adapted to be moved upward by rod 6|. which is operated by mechanical linkage 62 connected to. the pedals l6 as shown in Fig. 1. When movable rail 60 is moved upward, all the dampers 55 connected with the various strings are removed from the strings permitting the strings to vibrate freely. A spring 59 is secured to the fixed rail 39 and tends to hold the damper in the position in which the head 56 thereof engages the string 23.

In Fig. 3 there is illustrated the piano action of Fig. 2 with the various components thereof shown in the actuatedposition. As the key I3 is depressed, extension. 50 thereof is raised and bears against the head of the screw 49 causing the hammer butt 41to be rotated in a counterclockwise direction and the head 45 of the hammer to be moved to a position closely adjacent the string 23. Although the hammer is notpositively rotated to such a position that the head 46 thereof actually touches the string 23, the momentum of the hammer causes the movement to continue until the head strikesthe string causing the string to vibrate. Thehammer is then returned by spring 5| to the position Where the screw 49 engages the extension 59- of the key which engagement checks the movement of the hammer. As shown in Fig. 5 the spring 5| includes a loop 63 and end portions 64 and 65 which extend at right angles with respect to each other. This spring provides substantially uniform tension on the hammer butt 4'! regardless of the particular position of the hammer in its striking movement. By comparison of Figs. 2 and 3, it can be seen that although the tension in spring 5| is increased due to the upward movement of .the hammer butt 4'! this is counteracted by the forward motion of the hammer butt which tends to reduce the tension of the spring. As previously stated, the movement of the hammer butt 4'! by the key causes the damper to be raised so that the head 56 thereof is removed from the string 23. The head 56 on the damper remains in this position until the key 3 is released at which time the various components of the action are restored to-the position shown in Fig. 2.

As is apparent from Fig. 1, the screws 42 and 52 for adjusting the tension of the springs 4| and 5|, respectively, are positioned so that they are available without dismantling the piano in any manner. The springs 4| are adjustable to change the force required to operate the keys and, of course, can .be set to provide the touch desired by any particular person. The springs 5| are adjustable to provide the tension required for returning the hammers 45 to the normal position for operation and yet allow the hammer to swing relatively freely to strike the string with the necessary impetus to produce a clear tone. The action of the damper 55 can be adjusted by bending the book 51 so that the. damper is removed from the string 23 at just the right moment.

Referring now to Figs. 6 and '7, there is illustrated in thesefigures a modified piano action in which a whip and jack mechanism furnishes the operative connection between the key l3 and the hammer 45. In this structurea whip is pivotally supported on rail structure 36, being pivotally connected to a bracket 1| which also supports the hammer butt 12. A jack 13 is pivotally mounted on the whip 10 and includes a top edge l4 arranged to engage the rounded surface on the hammer butt 12. The jack '13 includes a screw 18. the head of which engages the surface Tl of the hammer butt 12 for a purpose to be explained. A spring 83 is secured to the whip l9 and includes a portion 84 engaging the jack 1'3 for holding the jack against the hammer butt. For providing a check for the hammer, a pin 18 is connected to the whip l0 and extends in an opening 19- in a rear projection 89 of the hammer butt 12. For transmitting the movement of the key l3 to the action, a screw 8| is provided in the whip Ill having a head 82 which engages the extension 5|] of the key l3. The ke I3 and hammer 45 are held in the normal position for operation by springs 4| and 5|, respectively, identical in every respect to the springs disclosed in Fig. 2. A damper 55 is also provided as in the previous modifications, the

damper in this instance being operatively connected to the whip 19 by a hook 85 anchored in the whip and extendin in an opening 86 in the body portion of the damper. The head 56 of the damper is held against the string 23 by a spring 59 as previously described.

Referring now to the operation of the structure of Figs. 6 and '7, as the key I3 is depressed the extension 59 thereof moves upward causing the Whip m to be rotated in a counter-clockwise direction. This movement is transmitted through the jack 13 to hammer butt 12 causin the hammer 45 to also rotate in a counter-clockwise direction. As is apparent in Fig. '7, as the whip is rotated the engagement of screw 16 in the jack with the surface 11 of the hammer butt causes the jack to be pushed away from the hammer butt and the edge 14 thereof to be moved clear to the rounded surface 15. This frees the hammer from the jack. As in the structure of Fig. 2, the hammer 45 is rotated by the action mechanism until it very closely approaches the string 23 so that the momentum of the hammer causes the rotation to continue until the head 46 of the hammer actually strikes the string 23. The hammer 45 is then moved toward the normal position by spring 5|, the motion of the hammer being checked by engagement of the pin 18 with the end 19a of the slot 19 as shown in Fig. 7. When the key [3 is released by the person playing, the projection 55 thereof moves downward and the whip I9 is released so that the hammer 45 can return to the normal position for operation as shown in Fig. 6. The spring 83 then moves the jack 13 to the position in which the of the damper.

The adjustment of the springs 4| and 5| in the action of Figs. 6 and 7 is identical to that in the action of. Figs. 2 and 3 and it is obvious that when this action is used in a piano as illustrated in Fig. 1, these adjustments are readily available from the top of the piano. The action of the damper 55 can be changed by bending the hook in a manner well known.

-In Figs. 8 and 9 there is illustrated a piano action which embodies a still further construction. This action is similar to'the action of Fig. 2 with the exception that the spring 5| is eliminated and a spring so is provided instead. The spring 99 is secured to a bracket 9| on which the hammer butt 41 is pivotally supported and is connected to the hammer butt 41 by a flexiblecord 92. The spring holds the hammer 45 against the stop 93 in position for the operation by key l3. It is noted that this provides a much simpler arrangement than the structure of Fig. 2 as the spring 99 is relatively short so that guiding means such as a rail 38 is not required. The damper 55 is secured to the hammer butt 41 by ,a hook 51 and cord 58 in exactly the same manner as in Fig. 2.

In Fig. 9, the action is shown in the operated position with the hammer head 46 positioned close to the string 23. As in the prior modifications the momentum of the hammer will cause the head to continue until it strikes the string 23 causing the string to vibrate. The hammer 45 is then returned by the spring 99 until the screw 49 engages the extension 50 of the key to thereby check the movement of the hammer. Upon release of the key l3, the hammer 45 is rotated in a clockwise direction by the spring 99 until it engages the fixed rail 93. As the spring 99 is a simple leaf spring the tension therein increases as the hammer 45 is rotated. This effect, however, is slight and, due to the extreme simplicity of the action, it is very satisfactory in many instances.

In each of the structures disclosed, the keys l3 can be removed from the action without affecting the adjustment thereof. This is sometimes necessary in repairing and adjusting the assembly. The individual units of the action, that is, the hammers, dampers, etc., are also individually removable making for easy servicing of the action.

From the foregoing description, it is seen that I have provided an improved piano action and key assembly having a down striking hammer which is adapted for use with a horizontal piano. The end-to-end relation of the key and hammer provides a shallow assembly making possible a horizontal operating structure having a very small vertical dimension. It is obvious that such a structure is required in a piano as illustrated in Fig. 1. Means are provided for adjusting the action to provide the desired operating characteristics and as previously stated the springs controlling the keys can be adjusted to provide the touch desired in any particular instance. The adjusting means are readily available making for easy adjustment of the action.

Although I have described certain embodiments of my invention, it is apparent that claims:

I claim:

1. A piano key'and action assembly comprising a fixed rail structure, a hammer including a buttpivotally mounted on said'railstructure, a whip pivotally mounted on said rail structure, a jack pivotally supported on said whip, a spring for holding said jack against said hammerbutt; a key frameya piano key supported on said key' frame and having a rear extension positioned to engage said jack, '9, second-spring secured to said fixed rail structure and engaging said-key, means for adjusting the tension of said second spring for controlling the force:required to operate said key, and a third spring secured to said fixed rail structure and engaging said hammer butt for" holding said hammer in the normal position'to be actuated by said key.

2. A piano key and action assembly comprisinga fixed rail structure, a hammer including a butt pivotly mounted on said rail structure and having a projection thereon, a key frame, a piano key supported on said key frame and-having an integral rear extension directly engaging said" projection on said hammer butt; a spring secured to said rail structure and engaging said hammer butt to hold said hammer butt in engagement with said rear extension for operation of said hammer by said key, and means for adjusting the tension of said spring forcontrolling the operation of said hammer.

3. Apiano key: and action assembly comprising fixed rail structuraa hammer including a butt pivotaly mounted'on said rail structure, a key frame, a piano key supported on said key frame 1 and including a portion operatively connected to said hammer butt, a spring secured to said fixed railtstructure and connected to said hammer butt forihol'din'g said hammer in the normal position to'be' actuated by said key, said fixed rail struc ture including a rail having a slot therein, said spring being positioned in said slot to be guided thereby.

CHARLES FREDERICK STEIN;

REFERENCES CITED The following references are of record in'the me of this patent? UNITED STATES PATENTS Number 1 Name Datev 5,990 Wise Dec. 26, 1848- 359,-557 Cahill Mar; 15, 1887- 374,389 Battes Dec. 6,1887 427,667-- Bunce et al May 13, 1890' 1,490,229 Perry Apr. 15, 1924 1,729,528 Todd Sept. 24, 1929 2,185,734 Loar Jan. 2, 1940 2,271,460- Miessner Jan. 27, 1942 FOREIGN PATENTS Number Country Date 22,267- Great-Britain 1891 513,122 GreatBritain Oct. 4,- 1939 31,247 Sweden 1 July 29, 1911

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