US1637539A - Harp damper - Google Patents

Description

.E. O. STARKE HARP DAMPER Aug. 2,1927. 637,539

Filed June 28. 1922 2 Sheets-Sheet 1.

7 E. o; STARKE HARP DAMPER Filed June 28, 1922 2 Sheets-Sheet 2 y ZmzZ Q/YZZQ? Maw/6w 59 3mm his fiflzeya;

Patented Aug. 2, 1927.

UNITED STATES PATENT orrica EMIL O.

,STARKE, or OAK PARK, ILLINOIS, AssIGNon TO THE RUDOLPH wunLIrzER COMPANY, 01' CHICAGO, ILLI oIs, A CORPORATION or ILLINOIS.

HARP DAMP ER.

Application filed June 28, 1922. I Serial No. 571,458.

damperfor the strings,'an'd' means for re liably operating the same, preferably pedal. tures of construction shown and described. as indicated in the claims.

In the drawings t Figure 1 is a side elevation of the upper part of a harpequipped with this invention.

Figure 2 bya v is a detail section of the base of the harp showing the pedals and connections for operating the damper. i 7

Figure 3 is aside elevation of one of the damper-supporting bars and the damper op-' erating cams thereon, with the operat ng connections thereto.

Figure 4 1s a section at the line, k4, on

Figure 1, on an enlarged scale. I v

Figure 5 is a detail plan view of, a portion of the damper carrying bars and por tion of the damper adjacent thereto with one of'the damper operating plungcrs and its cam. Y a

Figure 6 is asection at the line, 6-6, on Figure 5.

Figure 7 is a section at the line, 7'7, on Figure 5, showing the cam rocked for advancing the plunger. I

Figure 8 is a detail section at the line, 8-8, on Figure 7.

In the structure shown in the drawings, A is the pillar of the harp, B is the body, G is the neck and D, D, are the action plates for supporting the ordinary harp action, a certain element of which is shown at E (though not concerned in this invention). F, F are damper-carrying plates which are mounted on the lower end of the action plate and constitute in effect the extension of said plate, but which are themselves braced together by cross posts, F F so that the construction embodying this invention may be applied to and removed bodily from the harp. In the frame structure comprising the damper-carrying plates, F. F, there are mounted a plurality of plungers, Gr, their mounting being effected by means of pivotstuds, H, secured by screws, J, to the inner side of the one of the bars, F, Which is more remote from the strings, and the plungers, G, are reduced in diameter at one end portion for being mounted co-axially bored to fit slidably upon said studs, H. Each of these It consists in the elements and fea' plungers is provided with a spring, K, interposed between the bar, F, and the'shoulder, h, adjacent the reduced part of the plungen'as seen clearly in Figures 4, 5 and 6. On the ends of the plungers toward the strings, p,

there is secured a damper-carrying bar, L. on which there is mounted the damper, M, of felt or like suitable material. Mounted for rocking uponthe studs, H. are cams, N. These cams and the plungers, G, are externallyicylindrical and. of the same diameter and their proximate faces are oblique to the clyinder axis so that as theystand: in normal position, with the damper retracted. from the strings by the reaction of the springs, K, they constitute substantiallyia right cylinder diagonally slit. From this construction it will be-understoodthat upon the rocking of the cams, N, about the studs,H, the'plung'- ers, G.will be forced against the reaction of the springs, K, in direction for carrying the damper against the strings; and that by simultaneously rocking all the cams the damper Will be carried simultaneously throughout its entire length so as to damp the strings simultaneously. For so rocking the cams they are each provided with short lever. arm, N and these lever arms are con- 'nected successively along the entire length of the bars, F, corresponding to the contour of the action plate, D, by a continuous slightly flexible link, or, if preferred, byiridividual links, 0, running from each lever arm, N, to the next so as to operate substantially links, 0, being connected to the arm, P of the bell crank lever. P, which is mountedat the head of the pillar, A, overhanging the axial cavity of said pillar if it is hollow as shown. From said bellcrank lever arm an operating rod, Q, extends down along the pillar and is connected at its lower-end to a pedal, R, fulcrumed at 1" on the harp base, with its pedal, R in a position for operation by the player who will depress the pedal when he desires to advance the damper against the strings.

Upon considering the cam relation of the two parts, N and G, having their oblique faces abutting, it will be seen that as the cam, N, is rocked about the axisupon the first slight movement from position of complete abutment of the two faces upon each other, as seen in Figure 6, they would reas a continuous connecting linkage, the upper end of which or the last of said main in contact on iery of the cam; from which it would result that this periphery of theeam would rapidly wear or wear the opposing camfac'e of the plungerr-To a'void this result and to rovide a more satisfactory wearing surface or the two members upon each other, the elliptical cam edge ,of the plunger, G, may be rounded, as seen at g, in Figurev8,so as to-be curvilinear in radial section atall parts of the edge which will constitute the I wearing surface of the cam upon the scribed.

I claim w --1. In combination with a harp having a curved neek of conventional outline, a damper bar. of similar outline disposedhelow said neck adjacent the strings of, the harp, a pair of, platest'similarin outline to said bar and mounted in spaced relation to V register. horizontally therewith, a series of plungers attached to the damper bar at intervals in its length and slidably mounted in one of said.plates,-each of said plunger-s having an axial bore and a" guide stud rigidly carried by the other plate extending Pint I) said-bore of the plunger,said plunger bein formedwith a cam follower at, its inner en osed betweensaid plates, and a cam rotatab y mounted on the studbetween the follower and the plateffrom which said stud projects, together with means for rockingall of said cams simultaneouslyto force the dam er bar against the strings.

' 2. n combination with aharp having a curved neck which includes a pairof curved action plates embracing a downwardly open space back of the strings, a damper bar of curved voutline similar to that 01: the neck mounted adjacent the strings below said acplunger in the rocking action de tion plates and a pair of carrying plates for said bar extending respectively from the lower edges of the action plates and spaced apart to accommodate actuating mechanism for the bar, said mechanism comprising plungers attached to the damper bar at intervals in its length, extending perpendicularly frOm the plane of said bar and slidably mounted mom of said carrying plates, a cam associated with each plunger and rockable about-the'axis thereof for moving the bar toward the harp strings,.togcther with links connecting said cams for simultaneous operation and disposed between the two carrying lates, said plates being of such width as to ully mask saidlinks throughout the length of the damper bar. 7

3. In combination with a harp having a curred neck, a damper barof curved outline similar to that of the neck mounted adjacent the strings below the neck and a pair of carrying plates for said bar of like outline with the bar spaced apart and mounted behind it extending throughout the length of. the

bar; plungers attached to the damper bar atintervals in its length extending perpendicularly from the plane of .said bar and slidably through one of the carrying plates: cam means associated with each' plunger and rockable about the axis. thereof for moving the damper bar toward the harp strings, together with links disposed between, said carrying platesand curved to lie within the outlines thereof so as to be fully masked by said plates, said linksiconnecting the cams for simultaneous operation.

In testimony whereof, I have hereunto set my hand at Chicago, Illinois, this 17th day of June, 1922.

' EMIL o. STARKE,

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