An Improved Safety Ladder.
Year: 1890

page_text: Date of Application, 19th Nov., 1890
Complete Specification Left, 27th July, 1891-Accepted, 5th Sept. 189
PROVISIONAL SPECIFICATION.
An Improved Safety Ladder.
I, ARTHUR CALVERT, of Park Villa High Green, near Sheffield, Slater &c.,
do hereby declare the nature of this invention to be as follows:-
:-
This ladder consists of sides and staves. The sides Y are made of wood as in an
ordinary ladder but of a lighter section, but which are greatly strengthened by a
wire Z (galvanized or otherwise) inserted in a groove cut in the upper and lower
edges. The wire (which may be round or other suitable section) is tightly
stretched in the groove and secured by hooks staples or nails at suitable distances,
the 2 ends penetrating into the wood or secured by other suitable means.
The staves or steps X are made of galvanized iron or steel bent to a C section
or any other suitable form, into which is inserted the safety tread, consisting of a
piece or pieces of hard wood, fixed with the grain perpendicular to the tread and
projecting a little above the iron stave. This wood tread is wider in the iron stave
than on the tread so as to secure it in an upright position. The spaces between
the wood tread and interior of iron stave may be filled up with melted pitch or
other suitable cement.
I claim the invention of the iron staves containing the wood safety tread as
original, also the application of the wire to the ladder sides, or to anything which
requires strength and lightness combined.
Dated this 18th day of November 1890.
ARTHUR CALVERT.
COMPLETE
SPECIFICATION.
An Improved Safety Ladder.
I ARTHUR CALVERT of High Green near Sheffield in the County of York
Slater 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 :—
This invention has for its object to so construct ladders that they may be
considerably lighter than ladders constructed in the ordinary manner and of similar
lengths and equally as strong and likewise to so improve the staves steps or rungs
thereof that the foot of a person ascending or descending the same receives a safer
bearing than is the case with staves steps or rungs of the hitherto usual construction
to attain which I construct my improved ladder substantially as set forth in the
accompanying drawings in which
Fig. 1 is a cross sectional elevation and Fig. 2 a front elevation of my improved
ladder.
Fig. 3 is a. cross sectional elevation and Fig. 4 is a part front elevation in detail
illustrating my improved rung stave or step.
Fig. 5 is a cross sectional plan in detail of side of my improved ladder.
Figs. 6, 7, 8 and 9 are sectional plans of sides of my improved ladders illustrating
modified methods of strengthening the same.
Like letters of reference denote corresponding parts in each view.
The sides of my improved ladder are principally composed of wood and are
strengthened by means of a wire Z which is secured by means of staples or hooks y³
in a specially formed groove y'.
Instead of a circular section of wire or strengthening piece Z being employed a
channel section strengthening pieces may be used as shown at Figs. 6 to 9 in which

page_text: case each said piece is secured in the groove y¹ by means of nails or screws
I would have it understood that where a channel form of strengthening piece is
employed that I only fix the same to the leaning face of ladder side as shown and
not at the outer face. In some cases I place or fix the stiffening piece 2' in the
groovey and employ a circular section of wire also which latter rests in the
channel of said stiffening piece z' as shown at Fig. 8.
The staves rungs or steps X of my said improved ladder are composed of a
galvanized iron or steel portion which is bent to a channel or C section shown at
Fig. 3 and arranged to firmly grip the improved safety tread which is inserted
therein and which consists of a piece or pieces of hard wood fixed with the grain
perpendicularly to the tread aud which projects somewhat above the iron or steel
portion al.
I would have it understood that the said channel or C section a' may where
desired be applied to the underside of ordinary wooden rings steps or staves.
The said safety tread is wider where inserted in the iron or steel channel
portion than on the face of trend so that it is thereby secured firmly in
position.
The spaces between the wood tread and interim of iron or steel channel
portion may be filled up with pitch or other suitable cement.
Each side has holes formed through it for the reception of the ends of the iron
or steel channel portions and the sides Y are secured to said portions
means of nails or screws S see Fig. 4.
by
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. In a ladder the combination with a groove or grooves y¹ formed in the
sides Y of a wire or wires or strengthening pieces Z or substantially as
described.
2. Constructing ladders with staves steps or rungs X composed of channel
formed portion in combination with safety treads such as ² or with ordinary
wooden treads and secured to the sides in the manner substantially as described.
Dated 24th day of July 1891.
H. F. BOUGHTON, M. I. Mech. E.,
London, Sheffield, and Barnsley.