Improvements in Mechanism for Drawing and Withdrawing Curtains.
Year: 1889

page_text: Date of Application, 19th Nov., 1889
Complete Specification Left, 13th Aug., 1890-Accepted, 20th Sept., 1890
PROVISIONAL SPECIFICATION.
Improvements in Mechanism for Drawing and Withdrawing
Curtains.
I, MICHAEL LONGRIDGE, of 12 King Street, Manchester in the County of
Lancaster, Civil Engineer, do hereby declare the nature of this invention to be as
follows:-
My invention relates to improvements in mechanism for drawing and withdrawing
curtains and my improvements consist chiefly in substituting for the pole or straight
rod now generally employed a rod twisted or otherwise formed into a spiral and
supported in bearings so that by rotating the spiral the rings or equivalents by which
the curtain is suspended can be traversed along the rod and the curtain drawn or
withdrawn as desired.
In applying my invention to a window or doorway in which a curtain is drawn to
the middle from each side I form a straight length near each end of the rod coinciding
with the axis of the spiral and also a similar straight part in the middle of the rod at
which point the spiral is reversed. I support the rod upon the straight portions at
each end and in the middle as well if the length of the rod requires it and I rotate
the rod by means of a pair of pulleys and an endless band or by any other suitable
device. Near each end of the spiral the pitch is reduced so as to bring the supporting
rings as closely together as may be desired when the curtains are drawn back and to
prevent overwinding I place the bearings close up or fix a disc or equivalent at the
end of each short pitched portion of the spiral.
The spiral may be of polished brass or any suitable ornamental material or it may
be of unpolished but smooth material such as strong wire and it may be hidden under
a cornice or inserted in a hollow pole or tube having a longitudinal slot on the
underside in which the rings may slide.
It is not essential that the spiral should be of uniform pitch either throughout the
short pitched part or throughout the wide pitched part. The spiral may be made
with a varying pitch or with a pitch increasing from the ends towards the central
part but it is essential that the pitches should be short near the ends and that the
short pitched parts should be of sufficient length to contain the required number of
rings.
It will be obvious that for a single curtain the spiral would take the same direction
throughout and would not be reversed in the middle as above described.
H. B. BARLOW,
Agent for Applicant
COMPLETE SPECIFICATION.
Improvements in Mechanism for Drawing and Withdrawing
Curtains.
I, MICHAEL LONGRIDGE, of 12 King Street, Manchester in the County of
Lancaster, Civil Engineer, 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 :-
My invention relates to improvements in mechanism for drawing and withdrawing
curtains and my improvements consist chiefly in substituting for the pole or straight
rod now generally employed a rod twisted or otherwise formed into a spiral and
supported in bearings so that by rotating the spiral the rings or equivalents by which
the curtain is suspended can be traversed along the rod and the curtain drawn or
withdrawn as desired.

page_text: In applying my invention to a window or doorway in which a curtain is drawn
to the middle from each side I form a straight length near each end of the rod
coinciding with the axis of the spiral and also if required a similar straight part in
the middle of the rod at which point the spiral is reversed. I support the rod upon
the straight portions at each end and in the middle as well if the length of the rod
requires it and I rotate the rod by means of a pair of pulleys and an endless band or
by any other suitable device. Near each end of the spiral the pitch is reduced so as
to bring the supporting rings as closely together as may be desired when the curtains
are drawn back and to prevent overwinding I place the bearings close up or fix a disc
or equivalent at the end of each short pitched portion of the spiral.
It is not essential that the spiral should be of uniform pitch either throughout the
short pitched part or throughout the wide pitched part. The spiral may be made
with a varying pitch or with a pitch increasing from the ends towards the central
part but it is essential that the pitches should be short near the ends and that the
short pitched parts should be of sufficient length to contain the required number of
rings.
It will be obvious that for a single curtain the spiral would take the same direction
throughout and would not be reversed in the middle as above described.
And in order that my invention may be fully understood and readily carried into
effect I will describe the accompanying sheet of drawings reference being had to the
figures and letters marked thereon.
Figures 1 and 2 are views of a spiral curtain rod made according to my invention
for drawing a single curtain from right to left and drawing it back from left
to right.
Figures 3 and 4 are similar views respectively to Figs. 1 and 2 illustrating an
alternative arrangement.
Figures 5 and 6 are two views illustrating the construction according to my
invention of a double spiral for drawing two curtains one from each end towards the
middle and withdrawing the same.
Referring first to Figs. 1 and 2 in which the letters A B C designate the spiral rod
of varying pitch and of any suitable diameter. At A and C are two straight circular
portions coincident with the axis of the spiral and forming journals which are supported
by fixed bearings, not shown, in the drawing. The spiral may be caused to revolve
by means of an endless cord and a pulley D fixed on one of the journals A C or by
any other suitable device.
The numerals 1, 2, 3, 4, indicate the rings, hooks or links by which the curtain is
attached to the spiral, in the positions which they occupy when the curtain is drawn
back. The upper corner of the curtain may be attached at E to some stationary
part.
When the spiral is made to turn one revolution in the proper direction each ring
being prevented from rising by its own weight and by the weight of the curtain will
move longitudinally towards C through a distance equal to one pitch. When the
spiral has been made to revolve four times each ring will have advanced a distance of
four pitches towards C and will occupy the positions indicated by Fig. 2 and the
curtain will have been drawn to its full extent. Further revolution of the spiral is
prevented by the ring 1 coming in contact with the fixed bearing at C or with a disc
or stop fixed upon the spiral or upon some other convenient fixing.
When the spiral is caused to revolve in the opposite direction the rings will travel
back towards A and when it has revolved four times they will again occupy the
position shown in Fig. 1 and the curtain will have been drawn back. Further
revolution of the spiral in this direction is prevented by the ring 4 coming in contact
with the bearing A or with a stop conveniently placed.
The proper relation between the widest pitch and the diameter of the spiral
depends to some extent upon the smoothness of both spiral and rings and upon
the weight of the curtain; but generally speaking a pitch equal to twice the
diameter of the spiral will be found suitable.

page_text: To diminish friction it may sometimes be advisable to put one ring on every
second coil, as shown in Figs. 3 and 4, or on every third coil.
It is not necessary that the number of rings should be four, as there may be more
or less but the number of complete coils in the spiral should bear the following
definite relation to the number of rings, namely, if x = the number of rings, then the
number of coils must be 2 (1) or some multiple of 2 (x-1).
The spiral may be made with a varying pitch increasing uniformly or otherwise
from A to C but the pitch near the end A must be shorter than elsewhere in order
that the rings may be closer together when at the right end of the spiral than
when on other parts.
If instead of drawing the curtain from one end of the spiral to the other it is
required to draw two curtains one from each end towards the middle, then the
direction of the twist of the spiral must be reversed in the middle of its length
as illustrated in Figs. 5 and 6 and the pitch must be reduced at each end A A¹.
The description already given of the spiral for a single curtain will apply to each
half of the double spiral for two curtains.
If two curtains are to be drawn from the middle toward the ends then the short
pitched parts of the spiral must be in the middle.
When the spiral for two curtains is so long as to require support in the middle then
a straight circular part coincident with the axis must be formed at the point where
the direction of twist is reversed as shown in Fig. 6 and this part must be supported
in a suitable bearing so as to be free to revolve.
In order to bring the rings nearer together and thus give greater fulness to the
curtains at the point where they meet each other the pitch of the spiral can be reduced
near the middle if desired.
When more than two curtains are required to be drawn and withdrawn there must
be as many short pitched parts on the spiral as there are curtains.
The spiral may be of polished brass or any suitable ornamental material or it may
be of unpolished but smooth material such as strong wire and it may be hidden under
a cornice or inserted in a hollow pole or tube having a longitudinal slot on the
underside through which the rings may project and in which they slide.
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 :-
The improved mechanism for drawing and withdrawing curtains, said mechanism
consisting in its essential features of a spiral rod of varying pitch supported upon two
or more axial journals about which it may be caused to revolve by means of an endless
cord and pulley or equivalent device in order to traverse the curtain rings all
substantially in the manner and for the purposes herein set forth.
2000
H. B. BARLOW,
17, St. Ann's Square, Manchester, Agent for Applicant.
H. B. BARLOW,
17, St. Ann's Square, Manchester, Agent for Applicant.