Year: 1887

page_text: Date of Application, 30th July, 1887.
Specification Accepted, 27th Sept., 1887.
A Communication from
GEORGE JAWDUNE
RAWBONE, Artist, both of the city of Toronto, in the County of York, in the
Province of Ontario, Canada.
1, ALFRED JULIUS BOULT of 323 High Holborn in the County of Middlesex,
M.I.M.E. do bereby 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 :-
The object of the invention is to provide a fastener for frame joints which can be
cheaply made readily applied and effective in action; and it consists of a band formed
of a single piece of metal and having a circular or annular bridge between the arms
thereof and preferably attached to the inner corners of the frame and below the plane
of the back surface thereof and so shaped that when caused to spread it carries with it
and retains in position when spread the sides of the frame, the inner edges of which
when the fasteners are placed below the plane of the back surface thereof become
slightly sprung back from the under surface of the material stretched on the frame
and whereby no extra space is required for or taken up by them when a number of
frames are packed nor can the fasteners on one frame rub against or injure the canvas
on an adjoining frame when so packed for shipping or other purposes.
Fig. 1 is a perspective back view of the covered frame showing joint fasteners in
position.
Fig. 2 is an alternative form of joint fastener.
Fig. 3 is also an alternative form.
In figure 1 A is a frame the sides of which are made separate and held together by
the nails e so as to prevent twisting of the frame when the sides are spread. One of
the corners is broken away so as to exhibit one of the corner nails which is imbedded
in the sides. When the sides are caused to spread by the spreading of the arms of

page_text: the fastener they are slightly drawn from this nail which holds the sides from twisting.
The covering material M is attached to the outside edges of the sides at d being
turned over the edge for this purpose.
C is this fastener made of a single piece of metal which is preferably shaped and
located as shown in figure 1. a and the arms of this bracket shaped fastener are
perforated to receive nails that portion joining the arms together being bridged at c
and forming a circular or angular projection which is adapted to cause the arms to
spread under the influence of blows or pressure on the bridge c.
Having fitted these fasteners into the inner corners of the frame as indicated in
figure 1 and nailed by nails the arins thereof a and b to the inner sides of the frame
the canvas or covering material is then tacked on by tacks d round the four sides.
For the purpose of stretching the canvas more completely the angular or circular
bridge c formed between the arms of the fastener is struck a blow or succession of
blows which causes the arms a and b to spread carrying with them the sides of the
frame to which they are nailed and thereby fully stretching the canvas or covering
material M. The degree of tightness can of course be regulated by the extent to
which the arms of the fasteners are caused to spread under the influence of blows or
pressure. It will be seen that as the canvas or covering which is tacked to the outer
edges of the sides of frame is caused to stretch the inner edges of the sides of the
frame are sprung slightly back from the canvas and out of contact therewith so that
no wood line" can be formed on the canvas or covering material when stretched.
And it can be also seen that owing to the location of the joint fasteners they are
out of the way and cannot interfere or rub against so as to injure the canvas on an
adjoining frame when a number of them are packed together for the purpose of
shipping or otherwise. This form of fastener is specially adapted for frames for
stretching artists canvas.
In figure 2 which is an alternative form the joint fastener is nailed by its arms to the
outer corners of frame. A blow or blows on the angular or circular bridge c will
cause the sides of frame to spread and retain in position the sides so spread and
completely stretch the canvas or covering material tacked to the edges of frame.
Figure 3 shows another form being a flat fastener with the angular or circular
bridge c between the arms which are nailed on at the corner joints on the flat sides of
frame. A blow or blows on this bridge c will cause the sides to spread in a similar
manner and stretch the canvas or covering material tacked at d to the four outer edges
of frame. In neither of the forms shown in figures 2 and 3 will the fasteners be out
of the way when the frames are packed for shipping.
The various forms of bridge are intended to cover any other form of bridge which
may be adapted to cause the arms of the fastener to spread under the influence
of blows or pressure though the form shown in figure 1 is the preferable one.
joint fastener is preferablly made of "mild steel but may also be formed of any
other suitable material.
The
Having now particularly described and ascertained the nature of the said invention
as communicated to me by my foreign correspondents and in what manner the same is
to be performed I declare that what I claim is :-
1. A joint fastener bridged between the arms which are adapted to spread under
the influence of blows on said bridge substantially as specified.
2. A joint fastener formed of a single piece of metal and having a circular or
angular bridge formed at its centre and between the arms thereof which are adapted
to spread under the influence of blows on the said bridge substantially as specified.
3. A joint fastener C having arms a and b and a circular or angular bridge c
between said arms in combination with a frame A held together by nails e'substantially
as described and for the purpose specified.
4. The combination of a joint fastener 'C applied to the frame A at the corners
thereof and having a bridge c formed between its arms a and b which are perforated
to receive nails to attach it to the frame A substantially as described and for the
purpose specified.

page_text: 5. The combination of a joint fastener C rigidly attached at the joints to the inner
sides of the frame A and below the plane of the back surface thereof and having an
angular ar circular bridge c between its arms and at the angle of the joint fastener
adapted to cause the sides of the frame to spread as desired and the covering
material B attached to the outer edges of the sides of said frame substantially as
specified.
6. A fastener for joints rigidly secured to the inner edges of the frame and at the
corners thereof the arms of the said fastener to which the sides of the frame are
attached being adapted to spread under blows or pressure applied to an angular or
circular bridge between the arms and carry with them the sides of the frame so
as to stretch the covering material secured on said frame substantially as specified.
7. An adjustable joint fastener rigidly secured to the inner corners of a frame and
so formed that it may be caused to spread as desired carrying with it and retaining in
position when spread the sides of the frame to the outer edges of which a covering
has been secured substantially as specified.
S. An adjustable joint fastener rigidly secured to the inner corners of a frame
and below the plane of the back surface thereof in combination with the sides of
a frame the inner edges of which are sprung slightly back from the covering
material when the joint fastener is caused to spread so as to stretch the covering
material secured to the outer edges of the sides of the frame substantially as
specified.
9. The combination of a joint fastener C rigidly attached at the joints to the under
sides of the frame A and having an angular or circular bridge c between its arms a
and which are in the same plane and are adapted to cause the sides of the frame to
spread as desired and the covering material M attached to the sides of said frame
substantially as specified.