IMPROVEMENTS IN 'DERRICK' OR JIB CRANES
Year: 1880

page_text: LETTERS PATENT to Richard Bamforth, of Slaithwaite, near Huddersfield, in
the County of York, Builder, for an Invention of "IMPROVEMENTS IN
'DERRICK' OR JIB CRANES."
PROVISIONAL SPECIFICATION left by the said Richard Bamforth at the
Office of the Commissioners of Patents on the 22nd April 1880.
RICHARD BAMFORTH, of Slaithwaite, near Huddersfield, in the County of York,
Builder. "IMPROVEMENTS IN 'DERRICK' OR JIB CRANES."
This Invention relates to what are known as derrick or jib cranes, and the object
of my improvements is to render such cranes more serviceable, and to dispense with
the heavy counterbalance weights which are required upon cranes of ordinary
construction. According to my Invention I employ a rectangular travelling frame,
upon which is a circular railway. Upon the travelling frame is a triangular frame
mounted on pullies, and working upon a pivot on the centre of the circular railway.
At one corner of the triangular frame is fixed the "upright," and to the other
corners are fixed the "guys," which extend from the top of the upright.
The derrick or jib is secured at the bottom end to the centre of the triangular
frame, instead of being secured to the bottom of the upright as heretofore, whereby
the jib works in a more upright position, and the point of support is much nearer
to the load, the crane being more evenly balanced in consequence.

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent filed by
the said Richard Bamforth in the Great Seal Patent Office on the 22nd October
1880.
RICHARD BAMFORTH, of Slaithwaite, near Huddersfield, in the County of York,
Builder. "IMPROVEMENTS IN DERRICK OR JIB CRANES."
This Invention relates to what are known as "derrick" or jib cranes, whether
employed by hand or steam power, and the object of my improvements is to render
such cranes more serviceable, and almost to dispense with the heavy counterbalance
weights which are required upon cranes of ordinary construction.
According to my Invention I employ a rectangular travelling frame, upon which
is a circular railway. Upon the travelling frame is a triangular frame mounted on
pullies, and working upon a pivot on the centre of the circular railway. At one
corner of the triangular frame is fixed the "upwright," and to the other corners are
fixed the "guys," which extend from the top to the upright.
In order that the Invention may be better understood reference is given to the
accompanying Sheet of Drawings illustrative thereof. Fig. 1 is an elevation, and
Fig. 2 is a plan view of a “derrick" or "jib crane" constructed according to my
Invention. A is the rectangular travelling frame, having a circular railway line B
thereon; C is the triangular frame working upon a pivot D, allowing the triangular
frame C to run on the railway B by pullies E. To the upright G one end of the
guys H are connected, the other ends being fixed to the triangular frame; I is the
derrick or jib, which by preference is split or made in two parts, as shewn in
the plan. When it is desired to raise or lower goods the handle J is turned in the
ordinary manner, but when it is desired to turn the crane arround the winding or
lowering part of the gearing is disconnected, and the handle J again turned, by
which means the bevil wheels S are set in motion, operating the spur wheel or
pinion K in gear with the circular rack L fixed to the sides of the railway line B,
which moves the crane around into the position required. By this arrangement of
apparatus the counterbalance weights is materially lessen'd, consequently the cranes
requires less room; it is also more compact and less in weight.
Having thus described the nature and particulars of my Invention, I would have
it understood that I do not confine myself to the exact details hercin shewn and
described, as they may be varied without departing from the peculiar character of
the Invention, but what I consider to be new and therefore claim is,--
The combination and arrangement of the parts substantially as herein shown
and described, by which the counterbalance weight is materially lessened.
In witness whereof, I, the said Richard Bamforth, have hereunto set my hand
and seal, this Twentieth day of October, in the year of our Lord One
thousand eight hundred and eighty.