US2873638A - Piano abstract and assembly - Google Patents

Description

Feb. 17, 1959 M. D. CORWIN 2,873,633

PIANO ABSTRACT AND ASSEMBLY Filed Jan. 27, 1955 INVENTOR. Meier-0N a Cak'wnv,

BY allwnw A'r TORN E'YS.

United States Patent PIANO ABSTRACT AND ASSEMBLY Merton D. Col-win, Cincinnati, Ohio, assignor to The Baldwin Piano Company, Cincinnati, Ohio, a corporation of Ohio Application January 27, 1955, Serial No. 484,382

2 Claims. (Cl. 84-243) In United States Patent 2,548,890, Armand F. Knoblaugh described a type of drop action for small upright pianos characterized by a new type of abstract assembly. In the action, the wippens were located substantially below the level of the key bed and key board, and motion was transmitted from the keys to the wippens by means of elongated abstracts of rod-like form. The abstracts were bent over at their upper ends to form ledges or fingers overlying the capstan screws of the keys; and at their lower ends they were either flattened and provided with pins for pivotal connection to the wippens, or provided with axially extending, transverse, loop-like wire members for the same purpose.

The abstracts were guided in holes in a member removably mounted to the key frame or key bed, the holes being of a size to accept the bodies of the abstracts, and being connected to the edge of the guide member by slots of a lesser transverse dimension. It was possible to remove an abstract by disconnecting it from the wippen, pulling it upwardly through the guide member until its flattened portion or its wire loop began to enter the hole, turning it through about 90, and withdrawing it from the guide member laterally through the slot. It was also possible, by disconnecting the guide member from the key bed, to remove the whole action and abstract assembly from the instrument. When the abstracts were in use, their pivotal connection with the wippens kept their ledges or fingers in alignment over the keys.

A primary object of this invention is to provide improvements in drop actions of this type, and particularly in the abstracts thereof.

It is an object of the invention to provide piano abstracts and assemblies at substantially reduced cost.

It is an object of the invention to provide abstracts with enhanced strength in the pin area.

It is an object of the invention to provide abstracts which may be economically mass produced by die casting.

It is an object of the invention to provide abstracts which are more easily removed from the guide member, inasmuch as they do not require the rotary motion hereinabove described.

These and other objects of the invention, which will be set forth hereinafter or will be clear to the skilled worker in the art upon reading these specifications, are accomplished by that construction and arrangement of parts of which an exemplary embodiment will now be described. Reference is made to the accompanying drawings, wherein:

Fig. 1 is a vertical sectional view showing in assembly elements of the action, the abstract and a coacting key.

Fig. 2 is a partial perspective view showing the coaction of an abstract and the guiding means.

Fig. 3 is a partial perspective view of the end of a wippen.

Fig. 4 is a partial elevational view showing the lower end of the abstract and the forward end of the wippen in pivotal engagement.

2,873,638 Patented Feb. 17, 1959 Fig. 5 is a partial plan view of a modified guiding means.

In Fig. 1 an action is indicated generally at 1, mounted upon action brackets, one of which is shown at 2. A string of the instrument is shown at 3. The action brackets are normally mounted to the plate of the piano, not shown. The elements of the action are or may be conventional, and require no description here. The action, however, comprises a series of wippens, one of which is shown at 4. The wippens are pivoted, as at 5, to elements 6 affixed to a rail 7 in the action.

The key bed of the instrument is partially shown in section at 8. On the key bed there is a key fram 8a upon which is mounted a plurality of keys in the usual fashion, one of which is partially shown at 9. The rear ends of the keys preferably bear conventional capstan screws, as at 10. I

An abstract 11 is pivotally connected as at 12 to the forward end of the wippen 4. The abstract is guided by a guide means 13 preferably attached to the key bed 8, as shown. The upper end of the abstract has an angularly related ledge or finger 14 overlying the capstan screw 10. It will be clear from Fig. 1 how an upward motion of the rear end of the key 9 is transmitted by the abstract to the Wippen 4.

The guiding means for the abstracts is more clearly shown in Fig. 2 as comprising a plate of suitable substance, preferably of metal. For rigidity the plate may be provided with a flange 15 at its forward edge. The plate is provided with a series of holes 16 to accept the bodies of the abstracts in sliding relationship. These holes are connected with the rear edge of the plate by slots 17 having a width less than the diameters of the holes. Where the pIate of the guide member 13 is of metal, the holes and slots may be lined with a quieting material such as the felt strip 18. The plate will be provided with suitable holes 19 so that it may be attached to the key bed with suitable screws or bolts.

In Fig. 5 a guiding means is shown in which like parts have been given like index numerals. Instead of sounddeadening material applied as shown in Fig. 2, a strip of felt 33 may be adhesively applied to the upper or lower face of the plate 13. This strip will be characterized by holes 34 overlying the plate holes 16, and by slits 35 overlying the slots 17, the slits connecting the holes to the outer edge of the felt strip. The holes 34 are somewhat smaller in diameter than the holes 16 so that the bodies of the abstracts are prevented from contacting the metal plate 13. The felt body is sufliciently flexible to permit the withdrawal of the flattened portions of the abstracts through the slots 17 and slits 35 as hereinafter more fully described.

The guiding means may be mounted either to the key frame or to the key bed (preferably the latter, as shown); and if desired a strip of felt 36 in Fig. 1 may be interposed between the plate 13 and the surface to which it is attached.

The guiding means may be a single plate substantially the length of the key bed or a plurality of plates in end-to-end relationship, whichever is more convenient. Although the guiding means could be otherwise mounted, attaching it to the key bed takes care of reasonable dimensional inequalities between different instruments. If it is desired to remove the action from the instrument, the guide means may be disconnected from the key bed and tied back against the action rail 20, whereupon the action may be taken out of the instrument by disconnecting the action brackets 2. The abstracts, it will be noted, have no mechanical interlock with the keys.

The length of the abstracts may be varied as desired depending upon the dimensions of the instrument and the position of the action with respect to the key bed.

'The abstracts are made of suitably rigid material preferably of metal and are so designed that they may be easily and cheaply mass produced by die casting operations. They comprise an elongated cylindrical body 11 of appropriate length surmounted at the top by the :angularly related ledge or finger 14 which is flattened and preferably has a width greater than the diameter the light of the approximate angularity of the body 11 to the vertical in the finished instrument. The juncture of the ledge and the body may be rigidified as by a fillet 21 if desired. A sound-deadening material, such as felt or rubber, is useful where the ledge is to be contacted by the capstan screw; and this is conveniently applied in the form of a felt pad 22 beneath the ledge and held in place by adhesive. A locating shoulder for the sound-deadening material may be formed on the ledge at the position 23.

The lower end of the abstract is bifurcated to have a fork shape, as at 2 i with interspaced tines 25 and 26. It will be noted that the width of the fork is substantially greater than the diameter of the cylindrical body 111; and the fork may be made of any desired dimensions for adequate strength.

Adjacent the fork and, in eifect, connecting it with the body, there is a flat 27. This flat has a thickness less than the effective width of the slots 117 in the guide member 13. It will be apparent from Fig. 2 that the abstract may be disengaged from the guiding means by merely drawing it upwardly until the flat 27 may be withdrawn rearwardly through the slot 17. In doing so, it is not necessary to rotate the abstract since the fiat will be found in alignment with the slot when the abstract is merely moved axially.

The wippen 4, as shown in Fig. 3, will normally have a reduced front portion 28. This contains an opening 29 for the pivot pin of the abstract. The opening is bushed with felt or other suitable resilient material and is so formed as to have a slot-like opening below, as at 30. The tines 25 and 26 of the abstract are pinned,

as at 31. To accomplish this, the tines are drilled with suitably sized holes adjacent their lower ends and a wire of desired strength and substance is passed through the holes. The wire may be fastened permanently in position in any suitable way, as by flattening its ends beyond the tines. This is indicated at 32. When the abstract is assembled to the wippen, the wire or pin 31 is merely passed through the slot 30 in the wippen end.

To do this, the felt or other bushing has to be compressed.

d The pin will snap into position under the application of force, and the resistance of the bushing will be suflicient to overcome the weight and inertia of the abstract so as to prevent unintentional disengagement.

Since the fork 24 may be made of any size, it is not necessary in all instances to reduce the end of the wippen, as at 28, where the dimensions of the instrument permit. An individual abstract is readily removable at any time from the instrument by disengaging it from its wippen, then drawing it upwardly and disengaging it from the guiding member, as hereinabove described.

Modifications may be made in the invention without departing from the spirit of it. The invention having been described in an exemplary embodiment, what is claimed as new and desired to be secured by Letters Patent is:

1. An abstract for a musical instrument consisting of a one-piece die cast metallic element having an elongated substantially cylindrical body terminating at its upper end in an angularly related ledge, said cylindrical body terminating at its lower end in a fiat portion of lesser thickness than said body and a fork at the lower end of said flat portion, said flat portion and said fork extending in prolongation of said cylindrical body with the plane of said fork lying at substantially right angles with respect to the direction of extension of said ledge.

2. An abstract for a musical instrument consisting of a unitary die cast metalic element having an elongated substantially cylindrical body terminating at its upper end in an angularly related ledge having a width substantially greater than the diameter of said cylindrical body and a flat undersurface capable of receiving a pad, said cylindrical body terminating at its lower end in a flat portion of lesser thickness than said body and a fork at the lower end of said flat portion, said flat portion and said fork extending in prolongation of said cylindrical body with the plane of said fiat portion lying in substantial alignment with the direction of extension of said ledge and at substantially right angles to the plane of said fork.

References (Iited in the file of this patent UNITED STATES PATENTS Franklin June 30, 1953

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