IMPROVE- MENTS IN APPARATUS FOR RAISING, AND LOWERING, AND ADJUSTING VENETIAN BLINDS
Year: 1878

page_text: LETTERS PATENT to Henry Hughes, of No. 59, Blackstock Road, Finsbury
Park, in the County of Middlesex, Merchant, for the Invention of "IMPROVE-
MENTS IN APPARATUS FOR RAISING, AND LOWERING, AND ADJUSTING VENETIAN
BLINDS." Partly a communication from abroad by Ezra B. Lake, of New
Jersey. in the United States of America.
Sealed the 25th June 1878, and dated the 12th April 1878.
PROVISIONAL SPECIFICATION left by the said Henry Hughes at the
Office of the Commissioners of Patents on the 12th April 1878.
HENRY HUGHES, of No. 59, Blackstock Road, Finsbury Park, in the County of
Middlesex, Merchant. "IMPROVEMENTS IN APPARATUS FOR RAISING, AND LOWERING,
AND ADJUSTING VENETIAN BLINDS." Partly a communication from abroad by
Ezra B. Lake, of New Jersey, in the United States of America.
Venetian blinds are ordinarily raised by pulling cords which pass over pulleys
and through holes in the laths of the blinds, and are secured to the bottom lath, and
the laths of the said blinds are turned by pulling a cord affixed to the top lath.
By this arrangement considerable power has to be exerted in working the blind,
owing to the whole weight of it or of that part which is raised having to be over-
come by the pull on the raising cords, which, when the blind has been sufficiently
raised, have to be secured by being twisted over hooks or otherwise.
According to my Invention the blind is so balanced that it may be caused to
rise and fall by the exertion of very little force, the laths being turned in either
direction by slightly raising or lowering the blind.
In carrying out my Invention, I mount in bearings fixed above the blind, or in
another suitable position relatively to the blind, a shaft to which is secured a
conical drum, snail, or fusee, and one end of a spiral spring, the other end of which
is affixed to one of the said brackets or to some other fixed part. The raising cords of
the blind pass over pulleys in the top of the blind as usual, but instead of allowing
the ends of the said cords to hang down at the side of the blind as usual, I secure

page_text: the said ends to the periphery of the conical drum, snail, or fusee at its larger
end. By this means the weight of the blind is borne by the said spring, and the
said blind may be readily lowered by a slight downward pull and secured, as herein-
after described. The bottom lath of the blind being raised by the spring when the
blind is released. The said bottom lath may, if desired, be weighted; or, if preferred,
the cords, instead of being secured to the said lath, may be secured to a roller or
bar beneath it.
In order to lock the spring, and so arrest the upward motion of the blind when
it is at the desired height, I form on or affix to the fusee or the spring shaft a ring
or wheel, on the internal periphery of which I form ratchet teeth which engage
with a pawl jointed to a vibratory lover, working on a centre carried by one of the
brackets.
In the said lever I form a radial slot, through which the spring shaft passes, which
limits the motion of the lever. On the pin which forms the centre of the pawl
I mount a counterbalanced lever, the motion of which is limited by a stop on the
vibratory lover. This arrangement admits of the blind being drawn down at any
rate of speed, and of being allowed to ascend at a moderate speed without its
notion being arrested by the locking mechanism; but in case the blind should
escape from the hand, or be caused to move up rapidly, the said locking mechanism
comes into action, the counterbalanced lever being by the rapid motion of the ratchet
violently struck and turned on its centre, which motion causes the vibratory lever
also to turn or vibrate on its centre, and so bring the pawl jointed to it into such a
position that one of the teeth of the ratchet engages with it, and the motion of the
spring, and fusee, and blind are thereby arrested.
In order to further raise or to lower the blind, the pawl is disengaged from the
ratchet by a slight pull on the bottom lath; or instead of this arrangement the
blind may be held down by a cord, attached at one end to the bottom lath, and
capable of being secured at the other end by twisting it round hooks; or
any other convenient means for preventing the spring from winding up the
blind may be used.
To provide for the turning of the laths, I mount on the axes of the cord pulleys
on the top of the blind levers, having the form of an inverted T, and I suspend the
blind to the said levers by cords secured to the upper lath and to the horizontal
branches of the said T levers, which levers are connected by a bar, to which are
jointed two pawls, one or other of which engages, as horein-after described,
with teeth formed on the external periphery of the wheel affixed to the fusee.
By this arrangement when the blind is rising, the T levers are caused to rock on
their axes, the laths being thereby turned or inclined in one direction; and when the
blind is descending, the T levers rocking in the reverse direction cause the inclina-
tion of the lathis to be reversed, the rocking of the said T levers being caused by
the engagement with the toothed wheel of one or other of the pawls on the con-
necting bar to which an endway motion is thereby given.
In order therefore to turn the laths and adjust them at the required inclination,
all that is necessary is to slightly raise or lower the blind, and to arrest its motion
when the laths are sufficiently turned.
Instead of applying to the blind a single conical drum or fusee, as herein-before
described, two or more such drums or fusees may be applied to the said blind;
or a spring roller, or two or more spring rollers, may be substituted for the said drum
or fusee.

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent filed by
the said Henry Hughes in the Great Seal Patent Office on the 12th October
1878.
HENRY HUGHES, of No. 59, Blackstock Road, Finsbury Park, in the County
of Middlesex, Merchant. "IMPROVEMENTS IN APPARATUS FOR RAISING, AND
LOWERING, AND ADJUSTING VENETIAN BLINDS." Partly a communication from
abroad by Ezra B. Lake, of New Jersey, in the United States of America.
Venetian blinds are ordinarily raised by pulling cords which pass over pulleys
and through holes in the laths of the blinds, and are secured to the bottom lath,
and the laths of tho said blinds are turned by pulling a cord affixed to the top lnth.
By this arrangement considerable power has to be exerted in working the blind,
owing to the whole weight of it or of that part which is raised having to be over-
come by the pull on the raising cords, which, when the blind has been sufficiently
raised, have to be secured by being twisted over hooks or otherwise.
According to this Invention the blind is so arranged in connection with a spring
that the said blind when free to rise may be drawn up by the said spring, and
when required may be drawn down by the exertion of very little force, the laths
being turned in either direction by slightly raising or lowering the blind.
In carrying out this Invention, a shaft is mounted in brackets or bearings fixed
above the blind, or in any other suitable position relatively to the blind, to which shaft
is secured a conical drum, snail, or fusee, and one end of a spiral spring, the other
end of which is affixed to one of the said brackets or bearings, or to some other
fixed part. The raising cords of the blind pass over pulleys in the top of the blind
as usual, but instead of the ends of the said cords being allowed to hang down at
the side of the blind as usual, the said ends are secured to the periphery of tho
conical drum, snail, or fuseo at its larger end. By this arrangement the weight of
the blind when drawn up is borne by the spring, and the said blind may be readily
lowered by a slight downward pull. The said blind is or may be automatically
secured at any required height, as herein-nfter described, and is raised by the spring
when the said blind is released. The bottom lath may, if desired, be weighted, and
if preferred, a roller or bar may be attached to it, as illustrated in Figure 3 of the
accompanying Drawings, herein-after described.
In order to arrest the upward motion of the blind, and to secure it when it is at the
desired height, a cord may be secured at one end to the bottom lath, and be secured
at the other end by twisting it round hooks; or any other convenient arrangement
for preventing the spring from winding up the blind may be used.
To provide for the turning of the latlis, levers having the form of an inverted
T are mounted on the axes of the cord pulleys at the top of the blind, and the blind
is suspended to the said levers by cords secured to the upper lath and to the hori-
zontal branches of the said levers which are connected by a bar, to which are
jointed two pawls or catches, one or other of which engages, as herein-after
described, with teeth formed on the external periphery of a ring or wheel affixed to
or formed on the fusee. By this arrangement the laths are caused to incline in one
or other direction, according as the blind is being raised or lowered.
Figure 1 of the accompanying Drawings is an elevation of a Venetian blind, to
which the said improved apparatus is applied, the top bar of the blind and the
casing of the said apparatus being partly in section.
Figure 2 is a plan of the said blind and apparatus, the casing of which is
removed.
In these and in the other Figures of the Drawings, the same letters and figures of
reference indicate the same or corresponding parts.
A, A, are the laths of the blinds, and a is the top bar; B, B, are the brackets,
which form the bearings, in which works the shaft b¹; 6' is the snail affixed to the
said shaft, and 63 is the spring which is affixed at one end to the shaft b', and at the

page_text: other end to the top bar a¹; C, C, are the raising cords; c, c¹, are the pulleys over
which they pass, their upper ends being secured to the snail 6, and their lower ends
(as usual) to the bottom lath of the blind; c, c', are the levers affixed to the axes
of the pulleys c', c¹, to which levers the blind is suspended by the cords c³, c³; I is
the bar by which the said levers are connected, and to the ends of which they are!
jointed by pins i, i; 2, are the pawls or catches jointed to the bar I, their
motion being limited by stops 3, 3, affixed to the said bar; D is the ring or wheel
affixed to or formed on the snail or fusee b; d³, d³, are the teeth formed on the
periphery of the said ring or wheel D, with which teeth the free ends of the catches
,, engage; a² is the cord by which the blind is secured.
3
The action of the apparatus is as follows:-When the blind is being drawn down
the cords C, C, unwinding from the snail 6 turn it and the parts affixed to it in
the direction of the arrows, it being only necessary to pull with sufficient force to
overcome what may be termed the surplus strength of the spring 63, that is, the
strength over and above what is required to balance the blind. The said blind may
then be secured by twisting the cord a² round hooks.
When it is wished merely to reverse the inclination of the laths, the blind is either
drawn down or allowed to ascend for a short distance, the motion of the snail ba
through the engagement of the teeth d³, d³, with one or other of the catches i², i²,
pushing the bar I to one side or the other a sufficient distance to cause the
levers c, c, to rock on their axes, and thereby incline the laths in one or other
direction.
Although the arrangement for turning the laths has been herein-before described
and illustrated, in combination with that for raising the blind, it will be seen
that the spring barrel or fusee for raising the blind may be used without that
mechanism.
Figure 3 of the accompanying Drawings is an elevation, and Figure 4 is a plan
of a Venetian blind, to which an automatic locking apparatus for securing the
blind at the required height is applied.
In the blind illustrated in these Figures, the ordinary arrangement for turning
the laths is retained. The said locking arrangement is similar to that used with
some spring blind rollers, the said arrangement consisting of a pawl J, in which is
formed a slot j¹, through which passes a pin affixed to the bracket B; the said
pawl engaging with ratchet teeth d, e, formed on the internal periphery of the
ring or wheel D, as horein-after described. K is a roller attached to the bottom
lath of the blind, to afford a convenient hold in drawing down the blind.
This arrangement acts as follows:-When the blind is being drawn down, the
ratchet wheel is caused to move in the direction indicated by the arrows, the teeth
,, passing from under the nose of the pawl J, and throwing it into the position
indicated in dotted lines in Figure 3. The said pawl J may then be caused again
to engage with the ratchet d, and so secure the blind by allowing it to move up
for a short distance, the engagement of the teeth ², with the pawl J, throwing
it into the position shewn in full lines in Figure 3, in which position it prevents
the rotation of the spring shaft b' and snail b², whereby the ascent of the blind is
stopped.
When it is wished to raise the blind, it is first drawn down sufficiently to dis-
engage the ratchet from the pawl, without throwing it forward, in which position it
offers no obstruction to the upward motion of the blind at a moderate speed, but if
the blind move up rapidly, the friction of the teeth on the back part of the pawl
causes it again to engage with the ratchet.
Although I have described this as a convenient arrangement for securing tho
blind, I make no claim to it.
Instead of applying to the blind a single conical drum or fusee, as herein-before
described and illustrated, two or more such drums or fusees may be applied to the
said blind.
Having now described the nature of this Invention, and the manner in which it
is to be performed I wish it to be understood that I do not limit myself to the

page_text: precise details described and illustrated, as they may be varied without de-
parting from the nature of the said Invention, but I claim as the said Invention of
Improvements in Apparatus for Raising, and Lowering, and Adjusting Venetian
Blinds,"
Firstly. The application to Venetian blinds of spring, snails, or fusees (or their
equivalents) to which the raising cords of the blind are secured, and around which
they are wound by the action of the springs, whereby the blinds are raised,
essentially as herein-before described, and illustrated in the accompanying
Drawings.
Secondly. The combination with the spring, snail, or fusee aforesaid of the
apparatus, herein-before described, and illustrated in Figures 1 and 2 of the
accompanying Drawings, for automatically reversing the inclination of the laths
of the blind; that is to say, forming on the said barrel, snail, or fusee, teeth with
which engage pawls or catches, carried by a bar jointed to levers mounted on the
top bar of the blind to which levers the laths are suspended.
In witness whereof, I, the said Henry Hughes, have hereunto set my hand
and seal, this Tenth day of October, in the year of our Lord One
thousand eight hundred and seventy-eight.