US 769527 A
Description (OCR text may contain errors)
PATENTED SEPT. 6, 1904.
APPLICATION FILED 00T. 24,
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UNITED STATES Patented September 6, 1904.
SPECIFICATION forming part of Letters Patent No. '769.527, dated September 6, 1904. Application filed October 24, 1903. Serial No. 178,391. (No model.)
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Be it known that I, JOHN BAHR, a citizen of the United States, residing at Philadelphia, in the county of Philadelphia and State' of Pennsylvania, have invented certain new and useful Improvements in Drums, of which the following is a specification.
My invention broadly relates to drums, and particularly to that class wherein snares are placed in contact with the drumhead to impart thereto a sharp snappy tone, and said invention contemplates the provision of means whereby through the action of a single tension-controlling device a like degree of pressure may be simultaneously imparted to all points of a drumhead straining-hoop for the purpose of increasing the tension of the drumhead.
Further, such invention contemplates the provision of means whereby tension of the drumhead at any desired point of the straining-hoop may be increased or decreased without interfering in any way with the tension exerted upon said head at other points of the straining-hoop.
To the ends above set forth the invention consists in the construction, arrangement, and combination of the several parts comprised therein for service, substantially as is hereinafter set forth and illustrated in the accompanying drawings, wherein- Figure 1 is a bottoni planview of a drum constructed in accordance with my invention. Fig. 2 is a transverse sectional view of my improved drum, taken on the line X X of Fig. 1. Fig. 3 shows in inside elevation one of the tension-regulating devices detached from the drum. Figs. t and 5 are sectional detail drawings illustrating the manner of regulating the tension or pressure on any desired point of the straining-hoop, and Fig. 6 is a modification of the device shown in Fig. 3.
Similar numerals of reference in the several figures of the drawings denote similar parts.
In carrying out my invention I employ a shell 1, which may be made of any desired suitable material, and provide said shell with a single head 2 and straining-hoops 3 and 4, as is usual in this art. I provide the head 2 upon its inner surface with snares 5, which are rigidly secured at one end 6 to the inner surface of the shell and provided at their opposite ends with a tension-increasing device 7. To maintain the head 2 at proper tension, I provide the shell 1 upon its back with a series of radially-extending levers 8, the outer ends of which are fulcrumed (equidistant from each other) either upon the shell 1 or upon a rod 9, which is secured to the inner surface of said shell, as shown. In the present embodiment of my invention I show the levers 8 extending through a series of apertures 10, formed in the shell, as shown. This is, however, not essential to the proper action of the drum, as said levers may be fulcrumed upon the eX- treme lower edge of the shell, if desired. I provide the outer end of each of the levers 8 with a hook-shaped portion 11 to engage the lower edge of a slot 12, which is formed through one side of the lower tubular section 13 of an adjusting device 14, by which any desired one of the levers 8 may be made to impart a greater or less degree of tension to the drumhead than the remaining levers and without interferingI with said remaining levers. I provide the adjusting device 14 at its upper end with a tubular section 15, having a slot 1G to receive the hooked lower end 17 of a clamp 18, which extends over the upper edge of the straining-hoop 1, as shown. I provide the tubular sections 13 and 15, respectively, with a right-hand and a left-hand screwthreaded inner surface to receive, respectively, the right-hand and left-hand screw-threaded ends 19 and 2O of a rod 21, that is secured at its middle enlarged portion within a sleeve 2Q. I provide that the opposite ends of said sleeve 22 shall slide freely upon the tubular sections 13 and 15, and I provide said sleeve upon its outer central portion with a milled surface 23, whereby it maybe readily turned to move the sections 13 and 15 toward or from each other. (See Figs. 4 and I provide that the inner ends of each of the levers 8 shall extend above a plate 24, which, is centrally disposed as regards the shell 1 and is provided with inwardly-projecting tubular studs 25 to receive studs 26, which project from a bar 27, that extends from side to side of the shell 1 above the levers 3 and is held in position by ears 28, secured to said shell 1. I provide the bar 27 at its middle with an outwardly-projecting screw-threaded stud 29, that extends through an aperture 30, formed'through the plate 24,
. and `to and into a screw-threaded thumb-nut 31, which bears upon the outer surface of the plate 24. (See Fig. 2.)
rIhe operation of my invention will be apparent from the foregoing description, taken in connection with the drawings, since therefrom it will be clear that the upward movement of the thumb-nut 31 will simultaneously move the inner ends of the levers 8 inward, and since said levers are fulcrumed at points between their ends the outer ends of said levers will be movedbutwardly and will thus operate to impart tension to the head 2 through the adjusting device 14 and hoops 3 and 4.
Should it become necessary for any reason to4 increase or decrease the tension of the head at any particular point upon the straininghoops 3 and 4, it is only necessary to move the sections 13 and 15 of the adjustable device 14 toward or from each by the rotation of the sleeve 22 of one or more of the levers 8 nearest to the point at which the head is to be adjusted, after which the levers 3 may be moved by the nut 3l, as hereinbefore set forth.
I deem the capacity of the levers 8 for receiving independent adjustment with the head 2 of great importance in this art, as thereby the most perfect tension possible of the head is assured at all times.
ln Fig. 6 I show a modified form of adjusting device for the lower ends. In this form the upper portion of the adjusting device is provided at its top with a hook to catch upon the straining-hoops, and the lower end of said portion is provided both with a central screwthreaded aperture to receive a screw-threaded stud that projects upwardly from an adjustable head below and with a slot to receive the end of the lever 8, as shown. In action the head is turned to move the lever up or down.
Having thus described my invention, I claim and desire to secure by Letters Patent- In a drum an adjustable tension device or link comprising a screw-threaded section having a hook to engage a drumhead straininghoop, a screw-threaded section slotted to receive a lever to give tension to a drumhead, and a screw-threaded connection between said sections, in combination with a shell, a head thereon, a straining-hook therefor, a series of radially-extending levers fulcrumed on the shell to impart tension to the head, and mechanism to simultaneously move the inner end of said levers, substantially as described.
In testimony whereof I ailiX my signature in l presence of two witnesses.
JOHN BAHR. Witnesses:
WILLIAM H. H. KNIGHT, EDGAR E. SHAFER.