Improvements in Portable Scaffolds.
Year: 1889

page_text: Improvements in Portable Scaffolds.
We GEORGE S. MAO LAURIN Painter and JOHN H. CRANKSHAW, Insurance Agent
both of the City of Philadelphia State of Pennsylvania, and United States of America
have invented a certain new and useful "IMPROVEMENTS IN PORTABLE SCAFFOLDS"
and do hereby declare the following to be a full, clear and exact description thereof
reference being had to the accompanying drawing forming part of this specification :-
Our invention has relation to portable adjustable scaffolds and consists in the
devices for securing and adjusting the braces to the uprights at any desired height or
position, in adjustably securing the ledge boards to the uprights to any desired height,
in splicing the uprights and also in securing the brackets for supporting the foot-
planks to the uprights, all as hereinafter substantially set forth and described.
The object of our invention is to provide a safe and secure scaffold and one that can
be readily adjusted to any desired height.
In accomplishing the object of our invention I employ in combination with the
uprights, braces and brackets, locking plates adjustable on or fixed to the braces at
their respective ends adapted to engage upon fixed pins or spurs secured at desired
intervals to the uprights.
As it is desirable to affix the spurs or pins to two of the opposite sides of the uprights
principally for convenience in handling the uprights, the construction and design of
the securing plates on the respective ends of the braces are necessarily different in the
side braces from those in the front and rear braces.
We will now describe our invention so that others skilled in the art to which it
appertains may make and use the same reference being had to the accompanying
drawing forming part of this specification in which similar letters of reference refer to
similar parts throughout.
Fig. 1 is a perspective view of our scaffold erected and in position, built so as to
show all sides and the various parts in their several connections.
Figs. 2 and 3 show a broken cross beam or brace with their respective securing
devices secured to their respective ends, the securing device shown in Fig. 2 being
adjustable on the brace and that in Fig. 3 being fixed to the brace; the adjustable
device shown in Fig. 2 being employed when the locking pins on the uprights are on
the surface of the upright which is at right angles to the face of the upright on a plane
with the brace.
Fig. 4 is an end and partially cross-sectional view of the adjustable securing device
shown in Fig. 2.
Fig. 5 is a cross-sectional view of the fixed end securing device shown in Fig. 3 on
the line of Fig. 3.
Fig. 6 shows the end securing device fixed to the brace as shown in Fig. 3 showing
in detail the method of securing the same to the upright.
Fig. 7 is an adjustable brace-end securing device employed where the locking pins
are on the surface of the uprights in immediate contact with which the braces come,
as contradistinguished from the adjustable end securing device shown in Figs. 2
and 4.
Fig. 8 is an end view of Fig. 7.
Fig. 9 is the plate securing device secured to the other extremnity of the brace from
that on which the adjustable device in Fig. 7 is employed.
Fig. 10 is a cross-sectional view on the line y y of the securing plate and brace
end shown in Fig. 9.
Fig. 11 is an adjustable bracket for supporting a foot-plank.
Fig. 12 is a perspective view of the bracket shown in Fig. 11 having its
locking plates at right angles to the line of the locking plate represented in
Fio 11

page_text: Fig. 13 is the adjustable ledge board securing bracket in cross-section, showing
the securing ratchets on the upright and the movable pawl attached to the bracket.
Fig. 14 is a perspective view of the ledge board securing bracket, shown in
Fig. 13, detached from the upright.
Fig. 15 shows the splicing device for splicing the uprights.
A, A, are the uprights of the scaffold which are secured in position by the
oblique braces, B and B and the cross horizontal braces, C, C¹. All these braces
are secured adjustably to the uprights by means of the locking plates attached to
the ends of the braces, interlocking into the pins or spurs provided on the uprights.
a, represents the pins or spurs secured to the uprights, A, preferably on two opposite
sides, at desired intervals. These spurs, a, have preferably eliptical shaped heads
adapted to interlock with the securing plates attached to the cross-braces, and are
secured to the uprights, A, by riveting or otherwise. Affixed to one end of the
brace, B, is the securing plate, b, having an oblong or eliptical opening therein at
an oblique angle to the line of the brace, which is adapted to engage with the
horizontal head of the spur, or pin, a, secured to the upright, A. An opening or
recess, o, is provided in the brace, B, for the head of the spur or pin, a. under
the plate, b. At the opposite end of the brace, B, is an adjustable plate, 6,
adapted to engage on the spur, a, and interlock therewith, and adjustable on the
brace, B, to any desired point by means of the winged nut or screw, 6³, to secure
the brace, B, firmly to the upright, A.
It will here be noticed, as before stated, that as the spurs are preferably only on
two of the opposite sides of the uprights, A., that the securing plates adapted to
engage with the spurs, a, provided on the ends of the side braces, Bi, must
necessarily have to be at right angles to the line of its brace. At one end of
the brace, B, is pivotally secured the plate, c, at about a right angle to the plane of
the brace adapted to interlock with the spur, a, as shown in Figs. 5 and 6. At the
opposite end of the brace, B₁, is adjustably and pivotally secured the plate, c', as
shown in Fig. 4, adapted to interlock with the spur, a, and adjustable on the
brace, B, by means of the winged nut or thumb-screw, c, the plate, c', being
pivotally adjusted to that portion which encloses the brace, Bi, and which is bound
to the brace, B¹, by the thumb-screw, C².
o, is a space or recess provided in the braces, B, beneath the plate, b, to
accomodate the head of the spur, a; o¹ is an opening in the plate, el; o² is an
opening in the plate, c, and o³ is an opening in the plate, ', to allow of the entrance
of the head of the spur, a, when the plates and spurs are being fitted or locked
together.
D), represents the ledge board supporting brackets secured adjustably on the
uprights, A, adapted to be clamped thereto by tightening the nuts on the bolts, d,
as shown in Figs. 13 and 14 in detail, the turning of which draws together the two
L-shaped brackets shown in Fig. 14 and binds tightly upon the opposite sides of the
upright, A, and prevents the bracket and the ledge board, C, which it supports, from
slipping on the upright, A. As additional precaution, however, at about the points
where the ledge boards are usually secured on the uprights, A, 1 provide the
ratchets, d², counter sunk in the uprights, A, into which the pawls, d, provided on
the brackets, D, are adapted to engage.
E, represents the upright splicing plates secured to the lower end of the upright
desired to be added to the upright, A, to secure additional height. The hooks, e, of
the plate, E, engage upon the spurs, a, provided on the upper end of the upright, A,
and thus firmly secures the extension to the upright, A, and prevents the same from
slipping longitudinally or. laterally. G, is a bracket for supporting a foot-plank
having its securing plates, 9, 9, parallel with the line of the bracket, and G, is a
similar bracket but having its securing plates, g¹, gl, at right angles to the line of the
bracket. It will be seen that these two brackets are adapted to be adjusted to
different sides of the uprights.
•
When it is desired to erect a scaffold as shown in Fig. 1. or to erect a portion of
the same, as against a wall, the uprights having been temporarily supported, are.then

page_text: braced by adjusting to each the respective ends of the braces, B or B¹, by engaging
the locking plates on the respective ends of the braces with the spurs, a. attached to
the uprights, the desired distance between the plates on the respective ends
being regulated by means of the winged nut or screw on the adjustable plate at
one end of each brace. The scaffold is in this manner properly, readily, and firmly
secured and erected to any desired height by means of the splicing devices herein-
after described. The ledge boards may be secured at any desired position and the
brackets for supporting the foot-planks placed in position without loss of time, and all
without employment of hammer or nail.
The locking plates are preferably made with an orifice in the manner shown in the
drawings so as after admitting the head of the spur, a, the plate may drop slightly
down back of the head of the spur and thereby be secured in position; the length of
the shank of the spur, a, between the head and the face of the upright, A, is equal to
or slightly greater than the thickness of the end securing plate.
If desired both of the respective brace locking plates may be fixed to the brace
and neither adjustable. This construction I also employ and claim.
Having now particularly described and ascertained the nature of our said inven-
tion and in what manner the same is to be performed we declare that what we
claim is :-
1. In a scaffold in combination with the uprights and the braces the locking
plates fixed or adjustable and the fixed spurs substantially as hereinbefore set forth
and described.
2. In a scaffold locking plates in combination with fixed spurs and adapted to
engage thereon and therewith for securing the respective ends of the braces to the
uprights in the construction of the scaffold substantially as hereinbefore set forth and
described.
3. In combination with the uprights and cross pieces or braces of a scaffold the
spurs, a, fixed to the uprights, A, the fixed locking plates secured to one end of the
braces and the adjustable locking plates secured at or near the other end of the said
braces substantially as hereinbefore set forth and described.
4. In a scaffold the adjustable ledge board securing bracket, D, the binding
clamp, d', and the pawl, d, in combination with the ratchet, d³, affixed to the upright
substantially as herein before set forth and described.
5. In a scaffold a splicing plate, E, secured to one end of the upright to be spliced
in combination with the spurs, a, affixed to the end of the other upright substantially
as herein before set forth and described.
6. In a scaffold the bracket, G, for securing the foot-plank in combination with the
securing plates adapted to engage upon the spurs, a, affixed to the upright, A,
substantially as hereinbefore set forth and described.
7. In a scaffold the uprights, A, spurs, a, provided thereon, braces, B, B¹, C, C',
and fixed and adjustable locking plates provided on the braces adapted to interlock
with the spurs, a, each brace being provided with a locking plate at or near each end
thereof, one of the said locking plates being adjustable thereon, substantially as
herein before set forth and described.
Dated this 17th day of December 1880
HASELTINE, LAKE & Co.,
45, Southampton Buildings, London, Agents for the Applicants.