IMPROVEMENTS IN PULLEY BLOCKS, AND IN APPARATUS FOR RAISING, LOWERING, AND HOLDING FAST. WINDOW BLINDS
Year: 1877

page_text: LETTERS PATENT to Roger Vivian, of Tuckingmill, Camborne, in the County.
of Cornwall, Engineer, for the Invention of "IMPROVEMENTS IN PULLEY
BLOCKS, AND IN APPARATUS FOR RAISING, LOWERING, AND HOLDING FAST.
WINDOW BLINDS."
Scaled the 20th October 1877, and dated the 14th May 1877.
PROVISIONAL SPECIFICATION left by the said Roger Vivian at the Office
of the Commissioners of Patents on the 14th May 1877.
ROGER VIVIAN, of Tuckingmill, Camborne, in the County of Cornwall, Engineer.
"IMPROVEMENTS IN PULLEY BLOCKS AND IN APPARATUS FOR RAISING, LOWERING,
AND HOLDING FAST WINDOW BLINDS."
In the case of raising, lowering, and suspending heavy weights, I place at or near
the top of an ordinary pulley block, a pawl, which, when allowed to act freely,
shall bear on the rope or chain which passes between it and the pulley.
When the rope or chain is travelling in the direction necessary to raise the weight,
the pawl is of no service; but immediately the rope or chain is allowed to travel in
the contrary direction, the pawl comnes into action and prevents it from moving till
the pawl is released.
When it is required to lower the weight, the rope or chain is pulled a little
towards one side, which brings it into contact with one end of a lever, the other end
of which is thereby brought into contact with the pawl so as to prevent it from
pressing on the rope or chain; while the lever is in contact with the pawl the
weight may be lowered freely, but so soon as the pulley rope or chain is allowed to
return to its natural position, it ceases to actuate the lever, and the pawl comes
into action, whereby the weight is suspended till it is required to move it up or
down.
In the case of pulleys for raising, lowering, and holding fast window blinds, I fix
to the top rail of a Venetian blind a small frame having two or more pulleys and
an equal number of catches, between which catches and pulleys the cord for actuating
the blind passes.
When it is required to raise or lower the blind, the cord is to be pulled a

page_text: little diagonally towards the other side of the window to that in which tho
frame is fixed, when the cord passes freely over the pulleys and out of contact with
the catches.
To hold fast the blind in the desired position, the cord is to be brought towards
the side of the window in which the frame is fixed, to bring it into contact with
the catches, which nipping the cord between them and the pulleys, holds the
blind stationary till the cord is again pulled for raising or lowering, as may be
required.
For roller blinds, I fix to the window frame underneath the shieve on the end of
the roller a small pulley and catch frame, having one pulley and one catch, between
which pulley and catch the cord passes to and from the shieve of the roller, the catch
being actuated by the cord in a similar manner to that described in the use of
Venetian blinds.
SPECIFICATION in pursuance of the conditions of the Letters Patent filed by
the said Roger Vivian in the Great Seal Patent Office on the 14th November
1877.
ROGER VIVIAN, of Tuckingmill, Camborne, in the County of Cornwall, Engineer.
"IMPROVEMENTS IN PULLEY BLOCKS AND IN APPARATUS FOR RAISING, LOWERING,
AND HOLDING FAST WINDOW BLINDS.”
In the case of raising, lowering, and suspending heavy weights, I place at or near
the top of an ordinary pulley block, a pawl, which, when allowed to act.freely, bears
on the rope or chain which passes between it and the pulley.
When the rope or chain is travelling in the direction necessary to raise the weight,
the pawl is of no service; but immediately the rope or chain is allowed to travel in
the contrary direction, the pawl comes into action and prevents it from moving till
the pawl is released.
When it is required to lower the weight, the rope or chain is pulled a little
towards one side, which brings it into contact with one end of a lever hinged to one
side of the block, the other end of which is thereby brought into contact with the
pawl so as to prevent it from pressing with anything but its own weight on the rope
or chain; while the lever is in contact with the pawl the weight may be lowered
freely, but so soon as the pulley rope or chain is allowed to return to its natural
position, it ceases to actuate the lever, and the pawl comes into action, whereby the
weight is suspended and remains stationary till it is required to move it up or
down.
In the case of pulleys for raising, lowering, and holding fast window blinds, I fix
to the top rail of a Venetian blind a small frame, having two or more pulleys and an
equal number of catches, between which pulleys and catches the cord for actuating
the blind passes.
When it is required to raise or lower the blind, the cord is to be pulled a
little diagonally towards the other side of the window to that in which the frame is
fixed, when the cord passes freely over the pulleys and out of contact with the
catches.
To hold fast the blind in the desired position, the cord is to be brought towards
the side of the window in which the frame is fixed, to bring it into contact with
the catches, which nipping the cord between them and the pulleys, holds the
blind stationary till the cord is again pulled for raising or lowering as may be
required.
For roller blinds I fix to the window frame underneath the shieve on the end of
the roller a small pulley and catch frame, having one pulley and one catch, between
which the cord passes to and from the shieve on the roller, the catch being
actuated by the cord in a similar manner to that described in the case of Venetian
blinds.

page_text: DESCRIPTION OF DRAWINGS.
Figure 1 is a side elevation of a two shieve pulley block with the lever and paw!
in position. Figure 2 is a front elevation of the same with the lever in the
position it will take when not in contact with the hauling rope or chain.
The ordinary parts of the pulley block are not lettered. In addition to these, A
is a spring; B is a lever having its fulcrum on the frame, and the end C of this
lever serves as a bolt to lock the pawl; D is the pawl, it rests by its own weight on
the rope or chain, and when free inoves forward with it beneath the smaller roller E
until both it and the rope or chain become jammed.
The spring A, fixed either to the side of the pulley frame or to the lever, is for the
purpose of putting and keeping it in that position when lifting the weight or keeping
it suspended. When the hauling rope or chain is pulled down a little to release the
pawl, and is then held against the part of the lever marked B, B, the upper end of
the lever marked C is caused to pass into the frame behind the thin end of the
pawl, and the weight can be lowered freely. Should the rope or chain from any
cause be allowed to slip out of the hands of the person using it, the pawl will be
immediately released and the weight will remain suspended. From the form of the
bottom part of the lever it will be seen that it is capable of being actuated at
any angle that it may be necessary for the person to stand in when the block is
in use.
Figure 3 is a side view of the pawl; Figure 4 is a section of the same; Figure 5
is a view of the pawl looking at the under part of it.
Figure 6 shows two views of a frame, with two pulleys and two catches for
working with Venetian window blind cords; Figure 7 shows two views of the same
with a different form of catch.
Figure 8 shows two views of a frame and catch for roller blinds; the manner of
fixing this frame may be varied according to its requirements.
In these arrangements when the cord is held in such a position as to be clear of
the pawl, it is able to run, but when left loose it falls against the pawl which then
acts to lock it.
What I claim as my Invention is the lever of the pulley block, as described, for
the purpose of keeping the pawl out of action when it is required to lower the
weight or body suspended.
I also claim as my Invention in the case of blind holders, a frame with pulleys
and catches so arranged that the cord may pass freely on the pulley out of contact
with the catch when held diagonally, as described, or be brought into contact with
both pulley and catch, by allowing the cord to take the position it will assume
when it is out of the hand of the person using it.
In witness whereof, I, the said Roger Vivian, have hereunto set my hand
and seal, this Eighth day of November, in the year of our Lord One thousand
eight hundred and seventy-seven.
•
ROGER VIVIAN. (L.S.)