US399859A - Plumb-level - Google Patents

Description

A. B. EWING. PLUMB LEVEL.

(No Model.)

Patented Mar. 19, 1889.

M %w w/ MM h a arnr FI IIIEW ALVAN EW'ING, OF LEVVISBURG, TENNESSEE.

PLUMB=LEVEL.

SPECIFICATION forming part of Letters Patent No. 399,859, dated March 19, 1889. Application filed July 11, 1888. $erial No. 279,654. (No model.)

T0 at whom, it 72mg concern:

Be it known that I, ALVAN B. EWING, a citizen of the United States, residing at Lewis burg, in the county of Marshall and State of Tennessee, have invented new and useful Improvements in Plumb-Levels, of which the following is a specification.

This invention relates to a simple and convenient form of plumb and level, which may also be adapted for use in laying oil? bevels' and miters, for cutting rafters, braces, inclines, the.

The invention consists in a plumb-level. havmg certain peculiarities of construction, as hereinafter described and claimed, reference being made to the accompanying drawings, in which Figure 1 is a perspective view, partly in section, of my improved plumb and level as constructed for indicating angles, whereby it is adapted for laying off bevels, the. Fig. 2 is a view of the pendulum having an index or pointer.

The numeral 1 designates the stock, which may be composed of wood or metal, as preferred. In the center of this stock is formed a mortise, 2, having a curved bottom, 3, and end walls, I, that are partly in clined,the side walls being either vertical or inclined, as desired. The upper end of the mortise 2 opens on the upper edge of the stock and is covered by a curved plate, 5, having a longitudinal slot, 6, as shown. A pivot-pin, T, is passed through the mortise 2 and secured in the opposite side walls of the stock to support a pendulum, 8, that is accurately poised thereon. This pendulum may be of any desired form, though that shown in Fig. 9 is preferred, C0111- prising an enlarged or weighted lower portion, above which rises a vertical stem having a chisel or similar point, 9, at its upper end.

The pendulum 8 is provided. with. an. open ing, 10, for passage of the pivot-pin T, and it is prevented from lateral movement thereon by washers 11 on each side. The curved plate 5 on each side of its slot ii is provided with a center or level mark and is graduated to incate the degree of variation from a true level, as shown by the position assumed by the point of the pendulum. In one end of the stock 1,

at a right angle to the vertical axis of the mortise 2, is a similar mortise, 12, (shown by dotted lines,) covered by a plate, 13,provided with slot 14 and inclosing a chisel-pointed pendulum, 15, the construction being similar to that already described. It will be understood, of course, that the pendulum 8 is intended for indicating levels, while the pendulum 15 is for perpendiculars. The upper edge of the stock 1 is provided with oppositely-inclined bevels 1G, and an intermediate are, 17, having its convexity upward, as shown, the highest point of the are being on a level with the adjacent edge of the stock. The mortise 2 opens'on the periphery of the are 17 and is covered-by the aforesaid plate 5, which is curved to correspond with the are and provided with the longitudinal slot (5, through which the point of the pendulum can be observed. The curvature of the are 17 corresponds with the are described by the vibrations of the pendulum. This construction enables the plumb and level to be used for i11- dicating angles, and also for laying off bevels, &c., in a well-known manner. By placing the stock in a perfectly horizontal position a correct center-mark can be made on the plate 5 in line with the chisel-shaped end of the pendulum. This is the center or level mark. The graduations of a scale may be accurately obtained as follows: It the stock is twenty-four incheslong, I raise one end oneinchon the plate in line with the point of the pendulum. This elevation of one-half inch to the foot will give five inches in ten feet. I continue this opertion, raising the end of the stock one inch (more or less) at a time and marking the degrees on the plate. In this way any degree of: elevation desired may be obtained on each side of the center-mark until I have as many degrees marked as may be desired.

The stock may be made of wood or metal one and a quarter by three or four inches and of any length desired. It made of metal, the slotted metallic plates can be dispensed with. and the scale be marked directly on the stock. Each pendulum is made of :inetal and should have its lower end sui'iiciently heavy to enable it to vibrate and settle promptly.

The combined plumb and level is simple and inexpensive in construction and possesses the further advantages of strength, durability,

accuracy; and convenience of use; and is not liable to get out of repair.

What I claim is-= 1. A level having one horizontal edge formed with bevels 16, and an intermediate are, 17, a slot formed in said are, a mortise, 2, leading from said slot, and a pointed pendulum, 8, suspended in said mortise, substantially as described.

2. A plumb and level consisting of the stock 1, having one horizontal edge formed with bevels 16 a siotted intermediate am'iv, and a mortise, 2, and one end provided with a slot and a similar mortise, and a pointed pendulum pivoted in each mortise, substan- 15 tially as shown and described.

In testimony whereof I affix my signature in presence of two witnesses.

ALVAN B. EWVING. Witnesses:

S. D. DAVIS, J. A. EWING.

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