Improvements in the Construction of Ellipsographs.
Year: 1896

page_text: Date of Application, 8th July, 1396
Complete Specification Left, &th Apr., 1897-Accepted, 26th June, 18:7
PROVISIONAL SPECIFICATION.
Improvements in the Construction of Ellipsographs.
I, THOMAS MOY. of 8 Quality Court, London W.C., Engineer, do hereby declare
the nature of any said invention to be as follows:-
My invention relates to ellipsographs constructed upon the principle described
in the Specification to Letters Patent dated 8th November 1894, No. 21,508; and
the object of my present invention is to effect further improvements in the construction
of such instruments.
According to my present invention, I improve the instrument shown in Figs. 8
and 9 of my said former patent, by adding another limb to the operating limbs
therein described. This additional limb passes over the guides 41, 42, and carries at
one end the limb 44, with ball or point (or their equivalents) attached; and carries, at
its other end, the pencil or pen.
The limb 43, shown in Fig. 9, passing between the guides, is so pivoted to one or
more of the other limbs, that its angle of inclination can be regulated by a screw,
one or both of the ends being fitted with forked or other pivots and slides or their
equivalents; so that this limb operates in a similar manner to that above referred to,
while the additional limb affords a firm junction and support for the limb 44 and the
pen or pencil holder.
The invention described in my said former specification, as well as my present
invention, may be used in copying diagrains, and delineating toothed and other wheels
in perspective, as well as in delineating circles and straight lines, and ellipses
between those extremes, the respective diameters being regulated by the position of
the ball or point, and the angle of the limb 43.
When the instrument is used for copying or delineating drawings in perspective,
the frame 26 is removed and a wooden table takes its place, upon which the diagram
to be copied or drawn in perspective is placed. The height of the table above the bed
plate is equal to the height of the centre of the ball and the point of the tracer above
the surface of the bed plate.
COMPLETE SPECIFICATION.
Improvements in the Construction of Ellipsographs.
I, THOMAS MOY, of 8 Quality Court, London, W.C., Engineer, do hereby declare
the nature of my said invention and in what manner the same is to be
performed, to be particularly described and ascertained in and by the following
statement:-
My invention relates to ellipsographs constructed upon the principle described in
the Specification to Letters Patent dated 8th November 1894, No. 21,508; and the

page_text: object of my present invention is to effect further improvements in the construction
of such instruments.
And in order that my said invention may be particularly described and ascertained,
reference is hereby made to the accompanying drawings, in which similar figures of
reference indicate corresponding parts.
Fig. 1 is an elevation of the improved instrument.
Fig. 2 is a plan on the line a b of Fig. 1, showing the guides folded down upon
the base plate.
Fig. 3 is an elevation illustrating method of using the instrument when
delineating a drawing in perspective, or only copying the same.
Figs. 4, 5, 6 and 7 are illustrations of details.
5 is the base plate of the instrument having an opening cut out of the plate at 6,
so that, when it is laid upon the drawing paper, an ellipse (or other device) may be
delineated thereupon. 8 and 9 are two slotted guides, hinged to the base plate
at 10 and 11, so as to fold down when out of use, as shown in Fig. 2. Drawing
pins are passed through holes 12 in the plate for steadying the instrument upon the
drawing board, while in use. 13 is a rod or bar, one end of which carries the
rod 14, rigidly attached thereto at right angles at 13. 15 is a movable rod, screwed
to the rod 14, at 16. The lower end of this rod is fitted with a ball 17, forming a
detachable ball joint with the sliding screw nut 21.
Instead of forming the bars 14 and 15 in two parts with a ball at the lower end,
a single bar may be fitted having a point at its lower end to engage in a conical
recess in the nut 21. 18 is a detachable cradle pivoted to a stud at 19, about which
centre it is capable of revolving horizontally, as indicated by the dotted circle 20 in
Fig. 2. The nut 21 has an index or pointer marked thereon, for use in regulating
its position with regard to the semi-diametrical scale formed upon the edge of the
cradle 18, which commences with a zero point at the centre of the pivot 19, as shown
in Fig. 1, the divisions upon the scale being used to govern the longitudinal diameter
of the required ellipse, which will be double that of the scale. 22 is a tubular
holder for a pencil, pen, or graver 23, rigidly fixed to the rod 13, the pencil or the
like being secured in the holder 22 by a set screw 24. A scale, suitable for the minor
axis of the required ellipse, is engraved upon the holder 22. 25 is a regulating
screw, threaded into the sliding guide block 26, whereby the block 26 may be raised
from the lowest position, shown by solid lines in Fig. 1, to that shown by dotted lines
in the same figure. 27 is a bar pivoted to the block 26 at 29. 28 is a bar integral
with the bar 27, the bar 28 sliding in another (tubular) bar 30, pivoted to the
angular bracket 13ª at 31.
In using the instrument for delineating ellipses, the major axis is regulated by the
position of the block or nut 21 in the pivoted cradle 18, and the minor axis by the
position of the block 26 upon the tube 22. On turning the cradle 18 once round
the circle 20, the required ellipse is delineated by the pencil, pen, or graver 23. The
instrument may be adjusted to delineate a circle and a straight line, and any ellipse
between those extremes.
When the instrument is used for copying or delineating drawings in perspective,
the cradle 18 is removed and a wooden table 32 takes its piace, upon which is pinned
the diagram to be copied or drawn in perspective; as shown in Fig. 3, and by dotted
lines in Fig. 2. The height of the table above the bed plate is equal to the height
of the centre of the ball 21. The rod 15 is then unscrewed and the tracing point 1
attached to the bar 14. On tracing the lines of the diagram by the point 15" upon
the table 32, the required delineation is produced at the other end of the
instrument.
The frame of the instrument may be formed of tube, solid rod, square, or otherwise
shaped metal or other suitable material, a method of forming it of channel metal
being shown in Figs. 4, 5, 6 and 7. Also a single rod 33 may be substituted for
the rods 27 and 30, one end being made to pass through a slot in the elbow 13,
the rod 33 being slotted at 34 to work upon a pin 35, as shown in Figs. 4 and 5;
or the rod 33 may be made to slide in a pivoted guide 36, as shown in Fig. 6.

page_text: Fig. 5 is a side view of Fig. 4, and Fig. 7 shows another formation of the pencil
end of the instrument, the screw 25 passing through the channel of the arm or
limb 37, and being threaded to a lug, integral with the block 26.
Having now particularly described and ascertained the nature of my said inven-
tion, and in what manner the same is to be performed, I declare that what I
claim is:-
1. The improved construction of ellipsographs substantially as and for the purposes
described.
2. In an ellipsograph of the description aforesaid, the improved method of mounting
and manipulating the same substantially as and for the purposes described.
3. In an ellipsograph of the description aforesaid, the combination and arrange-
ment of the limb, bar, or rod 13, one end of which carries the generating bar and
the other the delineating bar and regulating screw, together with the adjustable
diagonal working in guides affixed to the base plate substantially as hereinbefore
described and illustrated by the drawings.
4. In an ellipsograph of the description aforesaid, the improved method of mounting
and manipulating the same substantially as and for the purposes hereinbefore
described and illustrated by Figs. 2 and 3 of the drawings.
Dated 8th April 1897.
GEO. DOWNING,
8 Quality Court, London, W.C., Agent.
GEO.
DOWNING,
8 Quality Court, London, W.C., Agent.