Improvements in Raising or Adjusting Mechanism for Window Sashes and other Sliding Articles of similar Character Required to be Raised and Lowered.
Year: 1887

page_text: Date of Application, 22nd Nov., 1837
Complete Specification Left, 9th Aug., 1888
Complete Specification Accepted, 19th Oct.,
1888
Improvements in Raising or Adjusting Mechanism for Window Sashes
and other Sliding Articles of similar Character Required to be
Raised and Lowered.
I, THOMAS WILKINS of 31, Crown Street, Liverpool, in the County of Lancaster,
Joiner, do hereby declare the nature of this invention to be as follows
This invention has for its object the obviating of the use of sash weights for window
sashes and the like. In place of balancing the sashes, I use a mechanical multiplier
so as to gain extra power to the hand.
The multiplier I prefer to use is the well-known device of the sheaf of pulleys.
The sash I suspend from above by two cords each of them passing over a pulley
keyed or otherwise fixed to a spindle running in bearings. On this spindle,
but running loose upon it, are the other pulleys of the top sheaf, and on the
sash are the pulleys or pulley of the bottom sheaf running loose on its bearings.
The cord is fixed preferably to the sash, passes over the fixed pulley, then down and
over the pulley on the sash, then again over one of the loose pulleys and so on for
the number of pulleys that are employed. In large sashes I may employ sheaves of
two or three pulleys respectively. On small sashes only sheaves of two and one
pulley.
The cord from the last loose pulley passes out over a guide-pulley by the side of the
frame. This guide pulley is pressed by springs on its bearings against a top plate.
A break cord attached to an abutment on the inside also passes over this pulley. The
two cords hang down together.
The break-cord has a convenient handle on its end.
To pull up the window sash, all that is required is to first pull on the break-cord
which at once pulls the guide-pulley away from the top plate and this leaves the
pulling cord free. The operator can now pull on the cord until the window sash is of
sufficient height, when by simply letting go of the break cord the sash cord is
tightened up.

page_text: By the peculiar mechanism which I have adopted the cords at each end of the sash
are equally employed in pulling the sash up, and the two pulleys over which they go
being of equal diameter the sash is pulled up evenly.
The bottom sash cord passes over a similar guide-pulley to that used for the top sash,
it also has a similar break cord.
It is preferable to have two differently colored handles for the two break cords, or
name them "top" and "bottom" respectively, or still better have them of different
lengths so that the top sash handle is rather higher than the lower sash break
handle.
In place of having an extra cord as a break, I may arrange it by placing the guide
pulley higher up than the ordinary pulleys so that the cord itself shall be its own break
cord, and thus do without the break cords altogether, or I may employ any other simple
well known blind cord break for the purpose.
Dated this 21st day of November 1887

page_text: By the peculiar mechanism which I have adopted, the cords at each end of the sash
are equally employed in pulling the sash up, and the two pulleys over which they go
being of equal diameter, the sash is pulled up evenly.
The bottom sash cord passes over a similar guide pulley to that used for the top sash,
it also has a similar brake-cord.
It is preferable to have two differently colored handles for the two brake-cords, or
name them "top" and "bottom" respectively, or still better have them of different
lengths, so that the top sash handle is rather higher than the lower sash brake
handle.
In place of having an extra cord as a brake I may arrange it by placing the guide
pulley higher up than the ordinary pulleys, so that the cord itself shall be its own brake-
cord, and thus do without the brake cords altogether, or I may employ any other
simple well-known blind cord brake for the purpose.
In thus illustrating my invention I do not confine it to the plan illustrated as it is
obvious that the pulleys need not be in sheaves, but that other forms by which the cord
can pass over several pulleys and rise and fall more than once, can be adopted, the
main point of my invention being, that in place of balance weights, I use multi-
plying pulleys, and, in the case of the top sash at least, these pulleys are embedded in
or fixed to the sides of the frame and sash, so that the sash can rise till it touches the
frame without the pulleys coming in contact with each other..
Having now particularly described and ascertained the nature of the said inven-
tion, and in what manner the same is to be performed, I declare that what I
claim is:-
1. The improvement in raising or adjusting mechanism for window sashes and other
like sliding articles, which consists in suspending them by multiplying pulleys so
arranged that the pulleys, though fixed to the frame and sash respectively, shall not
come in contact till the sash and frames themselves close tight against each other,
substantially as described.
2. The combination with sashes or the like sliding articles, of multiplying pulley
gear and brakes, substantially as and for the purposes described.
Dated this 8th day of August 1888.