US 2771808 A
Description (OCR text may contain errors)
NOV. 27, 1956 JENKINS, JR 2,771,808
BANJO TUNING DEVICE Filed Dec. 6, 1955 INVENTOR GEORGE JENKINS JR.
ATTORNEYS United States Patent BANJO TUNING DEVICE George Jenkins, Jr., Liberty, N. C.
Application December 6, .1955, Serial N 0. 551,359
2 Claims. (Cl. 84-304) The present invention relates to banjo tuning devices, and more particularly, to a banjo tuning device which can quickly change the tune of a banjo string during the playing of a melody.
A primary object of the invention is to provide a banjo tuning device of the class described above which will enable the player to change a string from standard setting to a different pitch during the playing of break-down tunes wherein such setting is required.
Another object of the invention is to provide a banjo tuning device of the class described which is adjustable to permit the limits to be preset so that the string can be moved from standard to a different pitch to give the same pitch each time the adjustment is made.
A further object of the invention is to provide a quick change pitch regulating mechanism which can be attached to a standard banjo without modifying the normal tuning peg construction.
A still further object of the invention is to provide a tuning mechanism of the class described above which is inexpensive to manufacture, easy to install, and simple in use.
Other objects and advantages will become apparent in the following specification when considered in the light of the attached drawings, in which:
Figure 1 is a fragmentary perspective view of the neck of a banjo showing the invention installed therein.
Figure 2 is an exploded perspective view of the invention.
Figure 3 is a side elevation of the invention with the banjo neck shown in dotted lines.
Figure 4 is a horizontal cross-section taken along the line 4-4 of Figure 3, looking in the direction of the arrows illustrating the device in one adjusted position.
Figure 5 is a view similar to Figure 4 showing a different adjusted position.
Referring now to the drawings in detail wherein like reference numerals indicate like parts throughout the several figures, the reference numeral indicates generally the neck of a banjo having a fret 11 extending transversely thereacross and being provided with upstanding tuning pegs 12, 13, 14 and 15 to which are attached for tuning purposes strings 16, 17, 18 and 19. The strings 16, 17, 18 and 19 extend from a sounding member (not shown) and are trained across the fret 11 as illustrated in Figure 1.
It should be understood, of course, that the strings 16, 17, 18 and 19 are anchored at their ends adjacent the sounding board and are normally tuned by tightening of the tuning pegs 12, 13, 14 and 15. In certain breakdown tunes the quick changing of the pitch of a string has been found to provide a much more pleasing rendition of the melody, and hence, many banjo players have attempted to provide this effect by loosening the tuning pegs 12, 13, 14 and 15, and then retightening them to return to a standard pitch. Obviously, the moving of the tuning pegs 12, 13, 14 and 15 in this manner can not accurately set the pitch of the string nor can it accurately reset the pitch of the string.
In the present invention, a cam 20 is positioned so that the string 18 will engage a circumferential groove 21 formed in the edge of the cam 20 and will be tightened and loosened by rotary movement of the cam 20 with respect to the neck 10. A bolt 22 extends through the neck 10 and has a head 23 on its lower end. An axial bore 24 extends completely through the bolt 22. A nut 25 is mounted on the bolt 22 above the neck 10 so that upon turning of the bolt 22, the nut 25 Wlll be locked to the neck 10.
The nut 25 is provided with an arcuate recess 26 having a stop shoulder 27 at one end and a lug 28 on the opposite end. Adjustable stop 29 is threaded through the lug 28 projecting into the recess 26 so that the end of the stop 29 can be positioned a variable amount from the lug 28. A threaded shaft 30 extends inwardly from the stop 29 and is provided at its outer end with a handle 31 and an outer flange 32. A coil spring 33 is positioned over the shaft 30 in engagement with the lug 28 at one end and the flange 32 at the other end.
A shaft 34 is secured to the cam 20 in offset relation to the axial center of the cam 20 and is provided with a pin 35 extending parallel to the shaft 34 beneath the cam 20. The shaft 34 is provided at its lower end with a squared socket forming member 36 which is screw threaded at 37 internally. A tubular collar 38 is engaged over the shaft 34 and has its upper end in engagement with the head 23. A key 39 encompasses the squared end 36 of the shaft 34 and has a bolt 40 extending therethrough and into the threaded bore 37 of the shaft 34. The top of the key 39 is in engagement with the bottom of the collar 38. The nut 25 is positioned on the neck 10 in such a manner that the handle 31 of the shaft 30 projects outwardly over the side edge of the neck 10 for ready adjustment of the stop 29.
It should be noted that in this position of standard tuning that the high point of the cam 20 is in engagement with the string 18 as illustrated in Figure 4, and by turning the key 39 the string can be loosened by moving the cam 20 away from its position as illustrated in Figure 4 into its posit-ion as illustrated in Figure 5. String 18 can be loosened to change the pitch thereof. By adjusting the stop 29 by rotating the handle 31 the amount of change from standard can be adjusted to any extent desired.
It should be noted that the spring 33 acts to prevent the setting of the stop 29.
Having thus described the preferred embodiment of the invention, it should be understood that numerous modifications and structural adaptations may be resorted to without departing from the scope of the appended claims.
What is claimed is:
l. A banjo of the type including playable strings, a tuning mechanism comprising a rotatable shaft mounted in the neck of said banjo, a cam engaging one of said strings and mounted on an end of said shaft, a stop mounted on said banjo engaging said cam limiting the movement of said cam in one direction, an adjustable stop on said banjo limiting the movement of said cam in the opposite direction, means for oscillating said cam between said stops, said bolt extending vertically through said banjo neck and has an axial bore through which said shaft projects, a nut threaded on said bolt with said stop being formed in said nut and said adjustable stop being threadedly carried by said nut.
2. A device as claimed in claim 1 wherein said cam is provided with a pin extending therefrom parallel to said shaft with said pin being adapted to engage said stops.
References Cited in the file of this patent UNITED STATES PATENTS 1,546,804 Stover July 21, 1925 FOREIGN PATENTS 162,542 Austria Mar. 10, 1949