US1849954A - Grand piano action - Google Patents

Description

March 15, 1932. M. RICHTSTEIG GRAND PIANO ACTION Filed Sept. 1'7, 1930 2 Sheets-Sheet 1 March 15, 1932. 3 1,849,954

GRAND PIANO ACTION Filed Sept. 17, 1930 2 Sheets-Sheet 2 Patented Mar. 15, 1932 BICEI'ISTEIQ, or o IcaGo, ILLINOIS GEAR? H ND C O Application filed September 17, 1930. Serial No. 482,388,

The assembly, installation, and. adjustment of piano actions constructed of such a large number of complicated and delicate parts is expensive and time consuming, and a piano action thus constructed requires frequent adjustment and repairs and when out of adjustment produces annoyin squeaks or noises. Amongother features which it is desirable to accomplish is the elimination of springs and other metallic parts which rust or corrode a'ndfshorten the life ofcthe action even under the bestconditions.

The device of my invention has no springs in its construction, and is made up of a relatively few simple parts. This simplicityof construction anl arrangement provides an action that seldom ncedsadjustment. Furthermore, since the device contains no springs or, silk cords, the tendencyof the action todi'sintegrate or break by reason of corrosion,

rust or decay, is minimized.

My invention has as its principal, object, the provision of ian improvedv piano. action comprising a relatively few, simple, rigid ne'mbers and connecting'jointswhichperform all of the functions of the more complicated piano actions.

A particularobject of the invention is the provision of a piano action having no metallic sp ngs or the like whereby the tendency to disintegration of the action by reason of-corrosion or rustingis minimized.

Another particular obj eoct is, the provision of-a piano action in which'all of the individual cooperating parts are pivotally mounted andare actuated by. thrust from an adjacent member.

In piano act-ions, asat present constructed, repetition of the notes, is accomplished only after the keys have travelled a substantial distance towards their normalinactive position. The device, herein described provides cooperatingparts so arranged that. aslight return movement of theckey, for example, not

more than one-sixteenth OfgilIi inch, will permit the note to be repeated. Because ofthe number of parts comprising a piano action as heretoforeconstructed and the manner of connecting suchjparts', eifectivemovement of the hammer isaccomplished only by a substantially complete movement of the action. By reason of the rigidity of each of the members comprising my action and the manner of their connection there is no lost motion of the connecting parts and a slight movement of the key instantaneously causes a corresponding movement of the hammer with which the action connects the key. A hammer may be caused to strike its wire by a slow movement of the keywith the result, however, that a soft note is produced. 7

Another object ofthe invention is the provision of a piano action operable for repetition of the notes upon a relatively slight return of the key following a stroke thereof.

:1 further object of the invention is the provision of a piano action operable to cause the hammer to strike the wire by actuating or depressing the key slowly, whereby a soft note is produced.

A still further object is the provision of a piano action which may be assembled and adjusted by persons having no mechanical skill.

Theinvention has among its other objects the production of a piano action which is economical to construct, convenient, durable, and satisfactory for use wherever found applicable.

Manyother objects. and. advantages of the construction herein described and shown will be obvious to to those skilled'in the art from the disclosure herein given.

To this end. my invention consistsin the novel construction, arrangement, and combination of parts herein shown and described and more, particularly pointed out in the claims.

In the drawings wherein like reference characters. indicate like or corresponding parts:

Fig. 1 is a longitudinal sectional view through a grand piano action embodying my invention Fig. 2 is a fragmentary plan view of the action;

Fig. 8'is a detail view to a larger scale showing certain of the members comprising my invention in theircooperating assembled relation; I

Fig. i is a sectional view along" the .line 4- of Fig. 3; and

Figs. 5 and 6 are respectively perspective views of individual mem ers comprising my invention which cooperate in the assembled structure to actuate the hammer to strike the piano wire.

in 11 coo aerates ith the ke 10 to hold and P guide the key against iateral movement. The pins 11 and 12 are respectively mounted on a front rail 47 and a bottom rail 18 carried by the frame 68. i

The key 10 is of the usual type of construction wherein a stroke of the key causes a wire 9 to be struck by a hammer 1a. The novelty resides in the construction and arrangement of the members operativel-y connecting the inner end of the keys 10 with a corresponding hammer 14 and a damper head 16.

The system of cooperating members which operatively. connect the key 10 with the hammer 14:, includes a capstan screw 13, mounted on the key 10. back of the balance pin 12 for the purpose of actuatinga whip or lever 21 upon movement resulting from striking the front end of the key. The whip or lever 21 is pivot-ally connected to a whip flange 27 by means of a center pin 29. The flange 27 is fastened to a whip rail 26 by means of a screw 28. The whip or lever 1, the rail 26, the flange 27, as well as the other members coop-. erating to actuate the hammer 1a are preferably constructed of light rigid material. I find seasoned maple satisfactory for the purpose. Thewhip 21 is provided with an ex;- tension 57 ireferably integral, as best shown in Fig. 5. The extension57 contains a hole 58 in whicn. the center pin 29 is inserted. A

q felt strip 64, mounted on the under side of the whip 21, provides a cushion having bearing contact with, and operatively connecting the whip with the capstan screw 13. An upwardly. projecting jack or member 22 is finedly mounted on the end of the whip 21'opposite to the extension 57. The upper end portion 59 of the jack 22 is convex and has bearing contact with a pad 61 suitably mounted on a shoulder 60 formed on the under side of arepetition lever 23. The lever 23 is of the third class and the shoulder 60 is convex downwardly and rearwardly and provides a mounting for the pad 61. The contacting surfaces of the jack 22 and of the lever 23 are convex, the curvature and direction of the conthe ack'22 when substantially elevated for a purpose hereinafter described.

A buttrail carried by front action brackets 20, provides a mounting and a support for the repetition lever 23. The lever 23 is fastened to the butt rail 30 by a butt flange 31. The butt flange 31 is fastened to the front edge of the rail 30 bya screw 32., The upper end of the flange 31 is bifurcated for the reception of an extension preferably integrally formed on the repetition lever 23. The repetition lever 23 normally rests upon a felt pad fastened on the top of the rail 30, the rail thereby providing a support for the lever when the lever is at rest. 1 pivot pin 33 pivotally connects the lever 23 with the flange 31, the extension 55 of the through a hole 53 extending through the recessed portion of the lever 23. The yoke 25' is provided with an aperture 51 in whi h the hammer shank 15 is inserted, as best shown in Fig. 3. The main bodyportion of the yoke 25 rest-s lightly upon a pad 62 positioned on the upper face of the free end of thelever 23 thereby assisting in supporting the hammerl which is connected with the other end of the shank 15.

A hammer rest i6 is positioned rearwardly i of and below the butt rail 36 to provide a support for the hammer 14: when the hammer is at rest. The hammer rest- 46 has a strip of felt 63 mounted on its upper portion upon which the hammer shank 15 lies when the hammer 14 is at rest. The position of the rest 46 below and to the rear of the rail 30 enables the hammer 14 to gain momentum rapidly when the jack 22 is thrust upwardly against the lever 23.

The hammer 14 is moved from i s position on the hammer rest 46 to its dotted line position of Fig. 1 by striking the front end of the key 10 in the usual manner. The stroke operates to move the whip 21, the jack 22 and the repetition lever 23 to their respective dotted line positions, as shown in Fig. 1. This movement of the various parts is occasioned by theoperating contact of the capstan screw 13 with the felt strip 6 1 positioned on the under face of the whip 21.

The capstan screw 13 is spaced from the balanced pin 12 at substantially one-half the distance from the pin to the outer end of the key 10. The screw 13 contacts with the lid wvhich actuates the lever. position of the hammer 14 corresponds to the lever 21 between its'mid-portion and its free end and as a result the movement of the jack 22 is greater than the movementof the outer end of the key 10. The jack 22 contacts with the lever 23 at a substantial distance from its pivot pin 24 so that the movement of the pin from its full line position to its dotted line position is considerably greater than the movement of the outer end of the key 10 The dotted line dotted line position of the key 10 and in this position the hammer is spaced a slight distance from the wire 9 to avoid'damping when the key 10 is given its maximum depression. The cooperating portions of the various levers are such that gravity prevents any loss of motion and all the levers move together. The pivot pin mountings for the levers and the absence of resilient members prevents any variation of the relative movements of the levers either upwardly or downwardly. The yoke 25 forms a portion of the shank 15 and its contact with the lever 23 adjacent to the pin 24 provides a construction wherein a slight upward movement of the lever 23 imparts sufficient momentum to the hammer 14 to swing the hammer upwardly in advance of the lever and thereby bring the hammer into contact with the wire 9 as a result of any slight movement of the lever. The hammer 14 immediately falls back to its position of rest on the lever 23 with the yoke 25 hearing against the pad 62, the spacing of the hammer 14 is such that it avoids any possibility of damping regardless of whether the levers are moved a maximum amount or moved only slightly.

If the key 10 is depressed either by a quick stroke or slowly, the hammer 14 will be brought into sounding contact with the piano wire 9. If the key is depressed slowly a light tone will be produced. After a stroke, the hammer 14 immediately falls away suificiently to clear the wire 9 and remains clear, even though the key is held in its extreme depressed position.

Since there is no lost motion between the various members comprising the action, if the depressed key 10 is permitted to rise slightly the hammer 14 will be correspondingly lowered. It is found in practice that by reason of the overlapping relation of the convex shoulder on the lever 28 and the convexed end of the jack 22, a return movement of the key 10 amountin to not more than one-sixteenth of an inch will lower the hammer 14 suiiiciently that upon again returning the key to its lowermost position through such one-sixteenth of an inch, sufiicient momentum will be imparted to the hammer to again cause it to strike the wire 9. An action comprising a largenumber of parts, some of which are flexible, requires an initial movement of the key considerably larger than of an inch in order to startthe hammer upwardly and to again cause it to strike the wire 9. This arrangement of cooperating parts permits a repetition of the hammer stroke by a key movement of not more than their resiliency or are worn away'and which are subject to'corrosion permits the action to function satisfactorily for an indefinite period.

The damper construction comprises a head 16 having a felt pad 17 normally in contact with the wire 9. A damper wire guide 19 is provided with an aperture 67 through which the wire 18 projects. A damper action bracket 34 provides a support for a damper lever stop rail 35. The damper construction is actuated by a lever 38 which projects over the end of the key 10. The lever 38 is thereby elevated when the key 10 is depressed and drops back as the front end of the key returns to its normal position. The lever 38 is connected at its rear end with a damper lever rail 41 by means of a pivot pin '42 and a flange 40 through which the pin projects.

By reason of the inner end of the key 10 being normally in contact with the under face of the damper lever 38 when the key 10 is moved to its dotted line position, the lever 38 is caused to move correspondingly to its dotted line position wherein the damper head 16 and damper felt 17 are elevated to their dotted line positions. The movement of the lever 38 and the damper head 16 is so coordinated with the movement of the hammer 14 as to cause the damper head 16 to clear the wire 9 before the hammer 14 contacts with the wire and to cause the head to contact with the wire upon elevation of the outer end of the key. A damper block screw 36 provides means for ad 'ustin or the effective len th of the damped construction; A pedal rail 89 positioned underneath the lever 38 has'a top felt covering 66 upon which the levers rest when in their full line position.

A sostenuto rod 43 is pivotally connectec with the damper construction by means of a sostenuto lip 44. The lip 44 is connected with the damper block by means of a spiral spring 45.

Thus, it will be seen that I have provided an improved grand piano action comprising a relatively few simple parts so arranged as to permit a repetition of the hammer stroke by a slight movement of the keys and which by reason of its simplicity is easily assemof he 7 V mounted on the whip lever and its bled and thenecessity for adjustment or for repairs is minimized. I

Having thus described my invention, it is obvious that various immaterial modifications may be made in the same without departing from the spirit of my invention; hence, I do not wish to be understood as limiting myself to the exact form, construction, arrangement, and combination of'parts herein shown and described or uses mentioned.

What I claim as new and desire to secure by Letters Patent is:

1. In piano construction the combination with a key and a hammer operable to strike a wire, of an action operatively connecting the hammer with the key, said action comprising a whip lever having operative engagement with the key, a repetition lever pivotally mounted above the whip lever, a pivotally mounted'shank connecting the hammer with the free end of the repetition lever, said repetition lever having a rounded shoulder on its lower face, and a jack having one end fixedly mounted on the whip lever and its free end in operative sliding and supporting engagement with said shoulder.

2. In piano construction the combination with a key and a hammer operable to strike a wire, of an action operatively connecting the hammer with the key, said action comprising a whip lever partially supported by and having operative engagement with the key, a repetition lever pivotally mounted above the whip lever, a pivotally mounted shank connecting the hammer with the free end of the repetition lever, said repetition lever having a rounded shoulder on its lower face, and a jack having one end fixedly free end in operative sliding and supporting engagement with said shoulder, the mounting and construction of said shank,'jack and levers being such that a depression and elevation of the key causes a corresponding elevation and depression of said levers, jack, shank, and hammer.

3. In piano construction the combination with a key and a hammer operable to strike a wire, of an action operatively connecting the hammer with the key, said action comprising a whip lever having operative engagement with the. key, a repetition lever pivotally mounted above the whip lever, a pivotally mounted shank connecting the hammer with the free end of the repetition lever, said repetition lever having a rounded shoulder on its lower face, and a jack having one end fixedly mounted on the whip lever and its free end rounded and in operative supporting engagement with said shoulder.

4:. In piano construction the combination with a key and a hammer operable to strike a wire, of an action operatively connecting the hammer with the key, said action comprising a whip lever having operative. engagement with'the key, a repetition lever pivotally mounted above the whip lever, a pivotally mounted shank connecting the hammer with the free end of the repetition lever, said repe tition lever having a convex shoulder on its lower face, and a jack having one end fixedly mounted on the whip lever and its free end in operative'sliding and supporting engagement with said shoulder.

5. In piano construction, the combination with a key and a hammer operable to strike a wire, of an action operatively connecting the hammer with the key, said action comprising a whip lever having operative engagement'with the key, a repetition lever pivotally mounted above the whip lever, a pivotally mounted shank connecting the hammer with the free end of the repetition lever, said repetition lever having a convex shoulder on its lower face and a jack having one end fixedly mounted on the whip lever and having its free end oppositely concaved and in supporting sliding engagement with said shoulder.

6. In piano construction the combination with a key and a hammer operable to strike a wire, of an action opera ively connecting the hammer with the key, said action comprising a whip lever partially supported by and having operative engagement with the key, a repetition lever, a pivotany mounted shank connecting the hammer with the repetition lever, and a jack having one end fixedly mounted on one of said levers, and its other end operatively engaging the other of the levers, the mounting and construction of said shan Z, jack and levers being such that a depression of the key causes a corresponding elevation of the levers, jack, shank and hammer, and recession of the key permits said levers, jack, shank, and hammer to be correspondingly lowered by gravity.

7. In piano construction the combination with a key pivoted intermediate its ends and a hammer operable to strike a wire, of an action operatively connecting the hammer with the key, said action comprising a plurality of cooperating third class levers positioned one above the other with the lowermost lever operatively engaging the key rearwardly of its pivot point, said hammer having a shank overlying the top of and hava pivoted connection with the uppermost lever, the points of cooperative engagement of said levers being so, arranged that any movement of the front end of the key pro: duces a corresponding enlarged movement of the uppermost lever at its point of connection with said shank. v

V 8. In piano construction the combination with key pivoted intermediate its ends and a hammer operable to strike a wire, of an action operatively connecting the hammer with the key, said action comprising a plurality of cooperating third class levers positioned one above the other with the lowermost lever operatively engaging the key rearwardly of its pivot point, said hammer having a shank overlying the top of and having a pivoted connection with the uppermost lever, the points of cooperative engagement of said levers being so arranged that said hammer is in close proximity to said wire when the front end of the key is held in its maximum depressed position.

9. In piano construction the combination with a key pivoted intermediate its ends and a hammer operable to strike a wire, of an action operatively connecting the hammer with the key, said action comprising a plurality of cooperating third class levers positioned one above the other with the lowermost lever operatively engaging the key rearwardly of its pivot point, said hammer having a shank overlying the top of and having a pivoted connection with the uppermost lever, a plurality of pins each providing a pivot mounting for one of said levers for said shank, the points of cooperative engagement of said levers being so arranged that any movement of the front end of the key produces a corresponding enlarged movement of the uppermost lever at its point of connection with said shank.

10. In piano construction the combination with a key pivoted intermediate its ends and a hammer operable to strike a wire, of an action operatively connecting the hammer with the key, said action comprising a plurality of cooperating third class levers positioned one above the other with the lowermost lever operatively engaging the key rearwardly of its pivot point, said hammer having a shank overlying the top of and having a pivoted connection with the uppermost lever, the length of the shank overlying its supporting lever being small relative to its effective length, the points of cooperative engagement of said levers being so arranged that any movement of the front end of the key produces a corresponding enlarged movement of the uppermost lever at its point of connection with said shank.

11. In piano construction the combination with a key pivoted intermediate its ends and a hammer operable to strike a wire. of an action operatively connecting the hammer with the key, said action comprising a plurality of cooperating third class levers positioned one above the other with the lowermost lever operatively engaging the key rearwardlv of its pivot point. said hammer having a shank overlying the top of and having a pivoted connection with the uppermost lever, a pluralitv of pins each providing a pivot mounting for one of said levers and for said shank, the length of the shank overlying its su porting lever being small relative to its efi ective length. the points of cooperative engagement of said levers being so arranged that any movement of the front end. of the key pro- MAX RICHTSTEIG.

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