US309852A - Ellipsograph - Google Patents

Description

(ModeL) H. T. HAZARD.

ELLIPSOGRAPH" No. 309,852. Patented Dec. 30, 1884.

mznesses n was PhuloLAhngrapher. WflSNIIILIM. In:

IJMTED STATES PATENT rrrcn.

HENRY T. HAZARD, OF LOS ANGELES, CALIFORNIA.

ELLIPSOGRAPH.

SPECIFICATION forming part of Letters Patent No. 309,852, dated December 30, 1884.

Application filed April 10, 1884. (Modem T (tZZ whom it may concern.-

Be it known that I, HENRY T. HAZARD, a citizen of the United States, residing at Los Angeles, in the county of Los Angeles and State of California, have invented a new and useful Improvement in Ellipsographs, of which the following is a specification.

My invention relates to that class of instruments used by draftsmen in drawing ellipses.

The object of my invention is to provide a simple, accurate, and convenient instrument by means of which a perfect ellipse of any desired size and form may be drawn with a single sweep of the pen or pencil. I accomplish this by means of the device described herein, and illustrated in the accompanying drawings, in which Figure 1 is a view of my ellipsograph as it appears while in operation. Fig. 2 is an elevation of the pen attachment viewed from the side next to the pen. Fig. 3 is a reverse view of the same. Fig. 4 is a section of the same on line as m, Fig. 3. Fig. 5 is an elevation of the pencil attachment viewed from the side of the blade which presses against the pencil. Fig. 6 is a section of the same on the line y y. Fig. 7 is a side elevation of the same attached to a pencil. Fig. 8 is an enlarged View of one of the divider-points.

The principle embodied in the pen attachment is identical with that employed in the pencil attachment; but owing to the different requirements of the pen and pencil they differ somewhat in construction.

In the drawings the same letters of reference are used for the similar parts of both attachments.

Ais the blade, which is curved to correspond with the blade of the pen, and is pro- 0 vided at its upper extremity with a drum, Z,

to which one end of a cord or thread is attached by being passed through a hole, L, in the flange B and secured by a knot in the cord. The hole L is countersunk, so that the knot 5 does not project from the face of the flange. A groove, G, extends along the blade from the drum to the point of the blade, Where the walls of the groove unite at the top, leaving a tubular opening, H, through which the cord 50 passes out at the point of the blade. A small projection, F, having an eye, I, through it, extends into the groove G a short distance from the point, to form an attachment for the other' end of the thread. The drum Z is mounted in a recess at the top of the attachment, and projects slightly beyond the inner face of the blade A, so that when it is attached to the pen the drum will'bear upon the pen, and will thereby become frictiontight. At the top of the attachment, as at D, there is provided a steady-pin, E, made to enter a hole made for that purpose in the blade of the pen, thereby steadying the attachment on the pen. In lieu of this steady-pin, two points may project out of the attachment and pass on either side of the pen-blade, whereby the hole in the pen-blade may be dispensed with. The blade has a hole, K, through which the adjusting-screw of the pen passes to secure the attachment to the pen. A 1011- gitudinal slot may be substituted for the hole K, so that the attachment may be raised or lowered to adjust the point H, through which the cord passes, at the proper distance from the point of the pen, whereby the same attachment is adapted to be used on different pens having different lengths of blade. The outer flange, G, of the drum is milled, so that the drum may be rotated by the thumb and finger.

The pencil attachment is the same as that above described, except that the blade is bent to correspond with the point of a pencil, and that, instead of the hole K and steady-pin E for its attachment, it is provided with aband, II, which encircles the pencil, and is provided with a set-screw, Q, toclamp the pencil in lace.

I believe the most desirable manner of securing the drum in its place is by making a threaded socket in it and fastening it to the blade bya screw, M, as shown in the drawings.

I adapt a pair of dividers to be used with this attachment by providing them with points having a small annular groove, P, and a shoulder, V, near the point, which is shown enlarged in Fig. 8.

When it is desired to use the ellipsograph,

a knotted cord is passed from the outside of I00 the'drum through the hole L, thence along the groove and through the opening H in the point of the blade, thence back through the opening H and through the eye I in the pro jeetion F, where it is secured by tying aknot on the end of the cord. Thus the attachment is provided at its point with a looped cord, J, one end of which is attached to the blade, while the other is attached to a drum, upon which it may be wound by rotating the drum. The adj Listing-screw N is then removed from the drawing-pen, and the attachment is placed upon the pen, allowing the point E to enter thehole provided in the blade of the pen for that purpose. The screw N is then passed through the hole K, which coincides with the screw-holes in the pen, and screwed into its place in the pen. \Vhen the screw is tightened to close the pen, the screw will clamp the attachment firmly to the pen, and the point E will prevent any lateral movement thereof. The loop .I is now placed around the points of the dividers, which are then set in the two foci-points of the ellipse. The pen is then placed at any determined point on the proposed boundary of the ellipse and the drum rotated until the thread is drawn tight. The pen, first being filled with ink, is then swept around the points, keeping the cord taut and allowing it to run in the notches I 1?, care being taken to turn the pen asitmoves around, so that at all points it will run parallel with its blades. The tendency of the cord is to hold it in such a position; but if it be heldrigidly in the fingers it will drag at points and blur the line, the pen turning once around in drawing the ellipse.

Ordinarily the dividers are held by the left hand and the pen in the right, and as the pen makes the circuit the dividers may be inclined away from the pen, so as to be out of the way of the right hand. The point of the blade A should extend verynearly to the point of the pen, and the notches I? I on the points of the dividers should extend as close to the bottom of the shoulder Vas possible, so that the cord will lie close to the paper while the line is being drawn, as the liabilityof error increases with the distance of the cord from the paper. The purpose of the shoulder 'V below the notch is to prevent the needle-point from entering the paper too far and binding the cord.

The pencil attachment shown in Figs. 5, 6, and 7 is operated in the manner above described, with the exception that less care is required to draw a neat ellipse. An ellipse drawn by this instrument is practically correct. If at any time the tension produced by the friction of the drum is not suflicient to prevent the thread from slipping, the thread may be drawn out of the groove and clamped between the blade and the pen or pencil.

What I claim as new, and desire to secure by Letters Patent, is-

1. A11 ellipsograph consisting of a pen provided with a drum or winding device, a cord confined near the point of the pen and there allowed to diverge to form aloop, one end 01' said cord being immovably attached to the pen and the other end attached to the winding device, and two stationary needles, around which the cord slips to guide the pen in drawing an ellipse.

2. In an ellipsographic attachment for a pen or pencil, a blade perforated at one end to admit a loop of cord, and being provided with means for attaching one end of the cord permanently thereto, and having a drum to which the other end of the cord may be attached, whereby the size of the loop may be regulated by rotating the drum.

3. In an ellipsograph, a 'pair of dividers each of the legs of which has an annular groove near its point, in combination with a drawing-pen provided with a winding device, and a pen-guiding cord attached at one end to the pen and atthe other end to the winding device, substantially as shown, whereby it is made adjustable as to length.

4. I11 an ellipsograph, the attachn1entA,having a drum, Z, the cord J, needle-points P l, grooved as shown, and the dividers and drawing-pen, all being in combination, substantially as shown and described.

5. In an ellipsograph, the combination of two needles or points, a pen or pencil provided with a drum or take-up device, anda cord attached to the pen at one end and to the takeup at the other end, said cord being made to diverge and form a loop encircling the points, such cord being confined or clasped at the point of divergence, substantially as shown, whereby the size of the loop is made constant while the instrument is being used.

6. In combination with a pair of dividers having their legs cireumferentially grooved close to their points, and thereby adapted to hold a pen-guiding cord close to the paper in drawing an ellipse, a pen-guiding cord seated in said grooves, and a drawing-pen attached to said cord, substantially as described.

7 In an ellipsograph, the combination of the blade A, having attached thereto the cordwinding drum Z and the pen guiding cord, with a drawing-pen and a pair of dividers the legs of which have an annular groove, all substantially as described and shown.

8. In an ellipsograph, the combination of a pair of dividers, a drawing-pen, a drum-carrying blade adapted for attachment thereto and having aperforation near its point, and a cord passing through such perforations and attached to said-drum and blade, respectively, substantially as set fortln 9. In an ellipsographic attachment for apen or pencil, a cord-winding drum extending beyond the line of the face of the blade of the attachment, so as to impinge against the pen or pencil and produce friction when-the attachment is in place, whereby the drum is prevented from slipping and loosening the cord.

' 10. In an ellipsograph, a pen-guiding cord immovably attached at one end to a pen or pencil, and movably attached at the other end IIO to a winding or take-up device carried by said device, and having a cord secured to said takepen or pencil, whereby the cord may be adup device, the cord diverging from near the jnsted as to length. point of the pen or pencil to form a loop to 11. In combination with a pen or pencil encircle two points or needles and guide the 15 5 having a hole or socket, an ellipsographic atpen or pencil in drawing an ellipse, substantachnient therefor having a point or needle tially as described. projecting laterally therefrom and adapted to enter the hole in the pen or pencil to steady HENRY T. HAZARDQ the attachment thereon. lVitnesses: 1o 12. An ellipsographic attachment for apen Jns. R. TOWNSEND,

or pencil, provided with a winding or take-up G. N. EARL.

Images