IMPROVEMENTS IN APPARATUS FOR RAISING AND LOWERING VENETIAN AND OTHER BLINDS
Year: 1868

page_text: PROVISIONAL SPECIFICATION left by James O'Donnell and Thomas
Arkill at the Office of the Commissioners of Patents, with their
Petition, on the 7th February 1868.
We, JAMES O'DONNELL, of Woburn Mews, West, and THOMAS
ARKILL, of River Street, Kings Cross, both in the County of Middlesex,
do hereby declare the nature of the said Invention for "IMPROVEMENTS
IN APPARATUS FOR RAISING AND LOWERING VENETIAN AND OTHER BLINDS," to
be as follows:-
Our Invention has for its object improvements in apparatus for raising
and lowering venetian and other blinds whereby they can be more
readily raised and lowered or retained in any desired position than
heretofore. For this purpose, according to one arrangement, we mount
an axis upon the fixed top lath or bar (or otherwise) of a venetian or
other blind. Upon one end or other part of this axis we fix a pulley,

page_text: by preference of larger circumference than the axis around which the
cord or line for actuating the axis and raising the blind is wound. The
lifting line or tape (one or more of which may be employed) attached
to the bottom lath of a venetian blind is attached to the axis so as to
wind thereon in the opposite direction to that of the cord around the
pulley. Below the pulley a lever click is suspended on axes, so as
to cause the pointed end or tooth on one of its arms to enter or fall
into the teeth of a ratchet wheel fixed on the pulley. The cord wound
on the pulley passes downwards through an eye or loop on the lower
end of the other arm of the lever click. The act of pulling the cord
to unwind it from the pulley raises or moves the lever so as to release
its end from engaging with the teeth of the ratchet, at the same time
causing the axis to revolve, and thus wind up the lifting line or cord
thereon, but directly the cord over the pulley is released the end of
the lever re-engages with the teeth of the ratchet, thus arresting the
rotation of the axis and retaining the blind in the position to which
it was raised. The lowering is effected in like manner by disengaging
the click from the ratchet and allowing the weight of the blind in its
descent to wind up the cord upon the pulley whilst held in a position
to prevent the click from engaging with the ratchet. In place of the
lever catch and ratchet previously described a lever break may be
employed according to this part of our Invention to arrest the descent
of the blind. The winding up cord in this arrangement in coming
from the pulley passes over a friction pulley or bar, carried by one
arm of the lever break (which is mounted on axes below the pulley)
and descends between a bar on the other arm of the break, and a
fixed bar against which it is nipped so as to retain the blind in any
desired position. To the lower arm of the lever break a cord is attached
by pulling upon which the winding up cord is released so as to raise
or lower the blind thereby.
Another part of our improvements consists in applying the lever
break previously described to one end of the top lath of an ordinary
venetian blind, the lifting cord passing downwards over a pulley
mounted on the lever, and between the other arm of the lever and
a fixed bar, the weight of the blind causing the cord to be nipped
between the fixed bar and the lower bar or arm of the lever break,
thus holding the blind in any desired position until released by pulling

page_text: the cord attached to the lower lever arm of the break. In applying
our Invention to other descriptions of blinds, they may be arranged
so as to be wound up on to the axis which carries the winding up
pulley and cord.