US53524A

US53524A - Improvement in trammels for ellipses

Info

Publication number: US53524A
Authority: US
Publication date: 1866-03-27
Anticipated expiration: 1883-03-27

Description

C. CROW.

- Trammel for Ellipses. No. 53,524. PatentedjMqrch 27,1866n UNITE STATES PATENT FFICE.D

CHARLES CROW, OF ONARGA, ILLINOIS, ASSIGNOR TO HIMSELE AND JAMES HOLLINGSWORTH, OF THE SAME PLACE.

IMPROVEMENT IN TRANiIVIELS FOR ELLIPSES.

Specilieation forming,- part of Letters Patent No. 53.5241, dated March 27, 1866.

To all whom it may concern: y

Be it known that I, CHARLES CROW, ot' Onarga, in the county of Iroquois and State of Illinois, have invented an Improvement. in Grad uatin g=Tramm els 5 an d I do hereby declare that the following` is a full and exact description thereof, reference being,` had to the accompanying drawings, and to the letters ot' reference marked thereon, in which- Figure l is a plan view of my improvement in graduating-trammels. Fig. 2 is a longitudinal elevation ofthe same. Fig. 3 is a perspective representation of one ofthe slides operating` in the grooves of the trammel-bed.

The object ot' my invention is to make five or more holes in the sweep ot' the elliptical trammel, in which holes screws or pins may be inserted into the slides operating in the grooves of the bed-plate, and in graduating these holes, by numbers, so that the relative length of the major and minor diameters of the ellipse to be struck may be definitely ascertained and understood.

To enable others skilled in the art to make and use my invention, I will describe the method of constructing' and using` the same.

A represents the common elliptical bedplate, containing,` the grooves C (l, in which operate the slides K, as shown at Fig. 3.

B shows the sweep, which revolves upon the top ot' the bed-plate A in the usual manner. D represents the adjustable sweep-head, th rough cal trammel, I will reler especially lo my improvement, which consists in making ve or more holes, as shown at 3' l i. l 3, through each of which the screws E may be inserted into the holes X of thc slides K. The screws E may be changed from one hole to the other for the purpose of striking` ellipses of different relative diameters.

Operation: In order to strike an ellipse whose minor diametershall be to the major diameter as seven to nine, the screws E in ust be inserted in the holes l l', and to strike an ellipse whose minor diameter shall he tothe major diameter as 8 to f), the screws E must be inserted in the holes 2 l', as represented in the drawings. In order to accomplish this the sweep B must be turned round upon the bed-plate A in the usual manner. The ellipse 1 (shown in the drawings) has diameters as seven to nine and the ellipse l 2 has diameters as eight to nine. Other comparative diameters maybe made hy inserting the screws in the holes 3' 3, or in holes represented by any other two numbers. 'Ihe size ot' the ellipse must be reg;- ulated by movingl the sweep-head l) upon the. sweep B, in the usual manner.

Having thus described my device, what I claim as new, and desire to secure by Letters Patent ofthe United States, is-

Ihe making` of ve or more holes in the elliptical trammel-sweep and graduating` the saine, as above described, for the purpose ot' which isinserted verticallyIhepencilormarkstriking; eliipses of different relative dialneing point H. F shows the set-screw, which ters, as set forth.

holds the pencil in place. G shows the screw which holds the sweep-head in the required place upon the sweep B, in the usual manner.

Having thus described the common ellipti- CHARLES GROW. Witnesses WINsLoW WooDs, H. C. MUNGER.