An Improved Canvas-stretching Device.
Year: 1890

page_text: Date of Application, 25th Mar., 1890-Accepted, 26th Apr., 1890
COMPLETE SPECIFICATION.
An Improved Canvas-stretching Device.
I, GEORGE COPE, residing at Sunny-slope Farm, East Bradford Township, Chester
County, State of Pennsylvania, United States of America, Artist, do hereby declare
the nature of this 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 devices for streiching canvas on frames and has for its
object to provide a complete and effective appliance for bracing and adjusting the
sides of the frame so as to tighten and maintain in proper tension the canvas secured
to them. My invention will be best understood after a description of the drawings in
which it is illustrated and in which―
Figure 1, is a plan view of part of the canvas-stretching frame with my improved
appliances secured upon it.
Figure 2 is a section on the line of Fig. 1.
Figure 3 a perspective view of my device in the form in which I prefer to
construct it.
Figure 4 a section on the line y y
Figure 5 a section on the line
of Fig. 3; and
of Fig. 1.
As
A A A are connected parts of the frame upon which the canvas is stretched.
shown, the parts of the frame are united at the corners by bevelled joints a and my
preferred construction is especially adapted for use with such bevelled joints. A¹ is a
brace such as is in large pictures used to stiffen the frame, and a¹ indicates the joint
which it makes with connected parts A of the frame. Bis a brace plate which serves
to brace the joint made by two connected pieces of the frame. At one end it is
provided with a screw-hole or holes b, and at the other with a slot 61; and the plate is
connected as shown so that the slot will lie at right angles to the joint formed by
connected parts of the frame. This construction and mode of application permits one
part of the frame to move away from its connected part in a direction at right angles
to the joint formed between them. In the brace plate I form a perforation e¹ at a
point which cones immediately over the line of the joint, said perforation being of
sufficient dimensions to permit of the insertion through it of a tapered screw E and its
function being to properly align and guide the said screw. When used in connection
with a joint such as or similar to a¹, the perforation is formed directly through the
body of the plate as is shown best in Figure 5. But where my device is intended for
use on a bevelled joint such as a, I form upon the plate B a downwardly-extending
gange lug C in the form of a right angle triangle with its right angle arranged as
shown so as to fit in the angle formed by two connecting parts A of the frame; and I
form the perforation e' through this gauge lug and in line with the bevelled joint a.
D D are screws by which the brace plate B is secured to the parts A of the
frame. E a tapered screw of dimensions which will permit it to pass through tho
perforations e and preferably fit neatly in it in its larger portions.
The brace plate is secured to the two adjacent parts of the frame as shown so that
its slot will be at right angles to the joint; in itself it stiffens and braces the frame
and when provided with a downwardly-extending gauge lug C nicely gauges the
position of the adjacent parts A and holds them with great rigidity and firmness.
The tapered screw E is then inserted through the perforation e¹ and screwed into the
joint which it forces apart, the adjacent parts of the frame moving away from each
other in a direction perpendicular to the line of the joint and being always braced and
held in proper relative position by the plates D. The tension of the canvas can thus
be nicely adjusted and re-adjusted at any time when it may become necessary; the
brace plates and screws remaining as a permanent part of the frame.
As shown in the drawings the tapered screws E are represented as thumb screws
but any ordinary screw can be used in the same way.

page_text: 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
First: In a canvas-stretching device, a brace plate having a slot at one end and a
screw hole or holes at the other end for securing it to connected parts of the frame
and having also a perforation formed in it so as to come in line with the frame joint
and serve as a guide for a tapered screw, all substantially as and for the purpose
.specified.
Second: In a canvas-stretching device, a plate B having a slot at one end and a
screw hole or holes at the other end for securing it to connected parts of the frame in
combination with the perforated gauge lug Ů secured to the plato and extending
down therefrom so as to fit in the angle of the frame and serve as a guide for a
tapered screw, all substantially as and for the purpose specified.
Third: In a canvas-stretching device, a plate B having a slot at one end and a
screw hole or holes at the other end for securing it to connected parts of the frame in
combination with the perforated gauge lug C secured to the plate and extending down
therefrom so as to fit in the angle of the frame, and a tapered screw E adapted to
pass through the perforated lug and into the joint of the frame, all substantially as
and for the purposo specified.
Dated this 24th day of February 1890.
HASELTINE, LAKE & Co.,
45, Southampton Buildings, London, Agents for the Applicant.