US555287A - Drafting device - Google Patents

Description

(No Model.)

T. F. HORRIGAN.

DRAFTI NG DEVICE 910 655,287. Patented Feb. 25, 1896.

UNITED STATES PATENT OFFICE.

THOMAS F. HORRIGAN, OF BOSTON, MASSACHUSETTS.

DRAFTING DEVICE.

SPECIFICATION forming part of Letters Patent No. 555,287, dated February 25, 1896.

Application filed December 18, 1895. Serial No. 572,569. (No model.)

To aZZ whom it may concern:

Be it known that I, THOMAS F. HORRIGAN, of Boston, (Brightom) county of Suffolk, State of Massachusetts, have invented an Improvement in Drafting Devices, of which the following description, in connection with the accompanying drawings, is a specification, like letters on the drawings representing like parts.

My invention relates to drafting appliances for the rapid laying out of circles and squares or other figures, as desired.

I have provided a simple and convenient device for quickly laying out circles, squares, and other figures with accuracy, and my device may take the place of other well-known drafting-instruments, or it may be used to supplement them,being extremely convenient and capable of instant use without special adjustment.

It is frequently the case that for various reasons it is not desirable to use the compasses in drafting various forms of symmetrical figures-as, for instance, when it is desired to avoid puncturing the paper or other object by the point of the compass.

In the accompanying drawings, illustrative of my invention, Figure 1 is a top plan view thereof. Fig. 2 is a vertical section on the line .00 a: of Fig. l, and Fig. 3 is a similar section showing the central positioning stud or eyelet in enlarged detail.

In the present embodiment of my invention A designates the body portion, which may be of any thin tough substance, preferably transparent celluloid and also prefer ably circular in form. At its center I provide the positioning-stud (1, (shown in the present instance as an eyelet,) which is loosely mounted on the body portion of the celluloid by means of the extended flanges a (L The periphery of the disk A is suitably protected by a rim a secured thereto. Extending from the center of the disk I provide a plurality of perforations, preferably arranged in symmetrical order to form the rectangularly-arranged series I) Z) and c These perforations may be equidistant apart or otherwise arranged, and are adapted to receive a pencilpoint, as illustrated in dot-ted lines at p.

In use the positioning. stud or eyelet is placed over the point which is to be the center of a circle or square and securely held in place by the finger, as shown in dotted lines at f. The pencil is then placed in the aperture to form the circle desired, if it be a circle, as shown, and the disk is revolved to produce the desired circle, as shown in dotted lines. If it is a square that it is desired to form, the points are taken-as, for instance, the points 2 2, &c.and these points are then joined by a ruler in the ordinary manner. T 0 make circles or squares of other sizes the dots 1 3 4:, &c., may be taken, as is clearly apparent. In order to form a triangle, the points, for instance, 2 2 5 may be taken, or any other set, according to the size and kind of triangle desired.

All the perforations may be numbered, and 1 in order to reproduce a figure exactly as the original the device is placed as desired and the pencil is inserted at the same numbers as in the original figure, and the duplicate is thereby readily formed.

It will be seen that by means of this device figures of various symmetrical outlines may be formed with accuracy and dispatch.

I do not desire to limit myself to the form or arrangement herein shown, as various departures therefrom may be made within the scope of my invention.

\Vhat I claim is 1. A drafting appliance,consisting of a body portion formed of a sheet of thin material, and a positioning-stud loosely supporting, and surrounded by, said body portion, whereby the latter may be rotated around said stud as a fixed pivot, the said body portions having a plurality of perforations at different distances from said stud to receive a marking-point, substantially as described.

2. A drafting appliance,consistin g of a body portion centrally mounted on an eyelet, in loose engagement therewith, whereby the same may be properly positioned and the body portion rotated on said eyelet as a pivot, the said body portion having a plurality of perforations to receive a marking-point at diiierent distances from said eyelet, substantially as described.

A drafting appliance, consisting of a transparent disk, centrally mounted on an eyelet, and having a plurality of perforations,

arranged in series, extending radially from. 10 said eyelet, substantially as described.

In testimony whereof I have signed my name to this specification in the presence of two subscribing Witnesses.

THOMAS F. HORRIGAN. lVitnesses:

FREDERICK L. EMERY, LAURA S. MANIX.

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