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.
1, 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 canvas-stretching devices and has for its object to provide
an appliance which can be secured to connected parts of the frame upon which the
canvas is stretched, and which will serve at the same time as a secure brace to the
frame and as a means for extending the parts thereof so as to tighten and keep tight
the canvas.
The nature of my invention will be best understood after a description of the
drawings in which it is illustrated and its novel features are hereinafter clear-pointed
out in the claims. In the drawings,―
Figure 1 is a plan view of a portion of the canvas-stretching frame with my improved
devices attached to it.
Figure 2 is a section on the line of Figure 1; and
Figure 3, a perspective view of a part of my device.
A A A indicate connected parts of the frame forming together joints a a or beveled
joints such as are indicated by the dotted lines marked a' a'. D is a brace plate
which is intended to be secured to the two connected parts of the frame as shown; it
is provided at one end with one or more screw holes b, and at the other end with a
groove b' and hold to the parts A of the frame by screws D passing through said holes
and slots. The brace plate should be secured to the frame in the position indicated
so that the slot 6' will run at right angles to a line bisecting the angle which adjacent
parts of the frame make with each other. C C are angular guage blocks, the angular
points of which should be approximately of 45 degrees so that when placed together
as shown they will make up a right angle which will fit in the right angle formed by
adjacent parts A of the frame. These guage blocks are secured to the brace bar B,
one of them by means of a slot 63 and screw D so that it can slide longitudinally upon
said bar, the other one C, is preferably secured permanently to the brace bar as by a
screw D passing through a hole in bar B, or it may be formed integral with said
bar. Upon the faces of the brace blocks C C which come in contact with the parts A
of the frame, I prefer to form projections or spuds c which will project into the
parts A of the frame and prevent the blocks CC from slipping. The brace bar or
plate B and the guage blocks CC having been secured together in the manner shown,
are then secured to the frame, and a tapered screw E is then inserted in the joint
formed by the abutting sides of the blocks C C₁ as indicated at c. As the screw
penetrates this joint the movable block C is forced apart from the block C and forces
the adjacent part A of the frame in the same direction, to wit, at right angles to the
line bisecting the angle formed by adjacent parts A of the frame; and this being the
line in which the slot lies the adjacent parts A A of the frame can inove apart
without resistance from the brace plate B. The canvas is thus brought to a proper
tension and can at any time be re-adjusted by moving the screws.
The device shown and described is especially intended for use with frames having
joints a which run parallel with one of the parts A making up the frame; but it is
equally applicable frames having bevelled joints such as are indicated by dotted
lines a¹.
Any tapered screw can be used in connection with my appliance as well as the
thumb screw such as indicated in the drawings.

page_text: Having now particularly described and ascertained the nature of my said inven-
tion, and in what manner the same to be performed, I declare that what I
claim is
First In a canvas-stretching device, the plate B having a slot at one end and a
screw hole or holes at the other end for securing it to adjacent parts of the frame in
combination with angular blocks CC both attached to plate B and one or both
adapted to slide thereon, substantially as and for the purpose specified.
Second: In a canvas-stretching device, the plate B having a slot at one end and
a screw hole or holes at the other end for securing it to adjacent parts of the frame in
combination with angular blocks C C₁ both attached to plate B and one or both
adapted to slide thereon; teeth cc projecting from the faces of blocks (which
come in contact with the frame, all substantially as and for the purpose specified.
Third: In a canvas-stretching device, the plate B having a slot at one end and a
screw hole or holes at the other end for securing it to adjacent parts of the frame in
combination with angular blocks CC both attached to plate B and one or both
adapted to slide thereon, and a tapered screw adapted to enter the space between
the said angular blocks and force them apart.
Dated this 24th day of February 1890.
HASELTINE, LAKE & Co.,
45, Southampton Buildings, London, Agents for the Applicant.