US313290A - Pendulum-lev el - Google Patents

Description

No Model.)

E. D. ORAMER.

PENDULUM LEVEL.

Patented Mar, 3, 1885.

' w/r/v ssss ByA Afforne'y $0 UNITED STATES PATENT OFFICE.

ELIJAH D. CRAMER, OF YOUNGSTOWN, OHIO.

PENDULUM-LEVEL.

SPECIFICATION forming part of Letters Patent No. 313,290, dated March 3, 1885.

' Application filed June 5, 1884. (No model.)

To all whom it may concern.-

Be it known that I, ELIJAH D. CRAMER, a citizen of the United States. residing at Youngstown, in the county of Mahoning and State of Ohio, have invented certain new and useful Improvements in Masons and Carpenters Instruments; and I do hereby declare the following to be a full, clear, and exact description of my invention, such as will enable others skilled in the art to which it appertains to make and use the same, reference being had to the accompanying drawings, which form part of this specification.

My invention relates to that class of masons and carpenters instruments which are employed to obtain lines and angles, and its object is to provide a convenient instrument, which constitutes a plumb-level and protractor combined, by the use of which levels, angles, and perpendiculars may be readily found by the workman with perfect accuracy and under any circumstances. I attain this object by the mechanism hereinafter described, and illustrated in the drawings, in which Figure 1 is aview of the index or face side of the instrument in a horizontal position, and Fig. 2 is an edge sectional view of the same in the same position. Fig. 3 represents a view, partly in perspective, showing the interior of the device.

Similar letters refer to similar parts in all the figures.

The body of the instrument is a rectangular timber, B, having its edges at perfect right angles, and being preferably, for ordinary uses, threefeet in length, four inches in width, and one and one-quarter inch thick. The attachment A, which is for the purpose of obtaining levels, is a rectangular box formed by a bottom and four sides of metal and a cover of glass, and is sunk into theface side of the timber equidistant between its edges near one end, so that the glass cover is on a plane with the surface of the timber, and the edges of the timber and the sides of the box are parallel.

The box for the size of the instrument above designated is preferably ten inches long, one inch wide, and five-eighths-of an inch deep. A thumb-screw penetrates from one edge of the timber to the box, which has a threaded hole in its side to receive it as a means of adjustment. Near the upper end of the box when perpendicular, extending from the bottom to the cover opposite, is a pin, I), which passes through apendulum-rod by a hole somewhat largerthan the pin except at the center of the rod, so that the pendulum, being weighted near its lower end, and provided with a fiat head a trifle smaller in breadth than thewid th, to maintain its position, freely oscillates right and left and backward and forward with the movement of theinstrument. At the breadth center of the bottom of the box, near the lower end, is a mark, 0, which the pointed lower end of the pendulum covers when the instrument is exactly perpendicular. The colors of the bottom of the box, the mark, and the pendulum are preferably in strong contrast, to enable the eye to note the position of the pendulum with greater readiness.

The attachment B is for the purpose of ob taining levels and angles, and is a semicircular box of metal covered with glass, the bottom of which is marked as a protractor, indicating, near the edge of the half-disk formed by the bottom, the degrees of a quarter-circle each side of a point directly below the'center of the whole circle, immediately below which is suspended a pendulum, weighted and sup ported as already described for the pendulum in attachment A. The box, which for the size of theinstrument already given is preferably six inches along the flat side and five-eighths inch deep, is embedded into the timber at its length center, so that i ts flat side is on a plane with the edge of' the timber and its cover on a plane with the face side, by which adjustment, when the instrument is brought to a horizontal with its opposite edge d0wnward, the pendulum will point to the lowest point on the bottom, and each variation of the position of the instrument from the horizontal will be indicated in degrees by the pendulum.

I do not limit myself to any particular size for my instrument, or any part thereof, nor to the device described to secure a free oscillation of the pendulums,for which purpose any efficient device may be employed.

As will be at once comprehended, this instrument readily shows levels, angles, and perpendiculars, and is very valuable to carpenters, masons, and other builders, both for its absolute accuracy and for the convenience with which it may be used. It is especially the pivot-pin b, extending through the upper useful in getting perpendiculars in a wind part of the said box, and enlarged at its cenwhich disturbs the accuracy of the plumbter, as shown, and the pendulum mounted line, and in keeping the proper angle in batupon said pivot and adapted to swing later- 5 tering back walls, for which the instruments ally as well as back and forth, the instrument 20 now used are defective. It is evident that it being provided with a center-mark, c, to cenwould be useful in surveying. ter the free end of the pendulum, substantially I am aware that a protractor without apendas specified. ulum for obtaining lines and angles is old, In testimony whereof Ihavehereunto afiixed 10 and I do not claim such to be my invention. my name and seal in the presence of two wit- 25 What Ido claim as my invention, and desire nesses.

to secure by Letters Patent, is ELIJ AH D. ORAMER. [L. s.]

In an instrument for obtaining perpendicu- Witnesses: I lars, the straightedge or timber 13, having a JAMES F. \VILSON, r 5 rectangular box, A, with a transparent front, L. D. WOODWORTH.

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