in Coiled or Partially Coiled Objects, or in some Cases where a Brake is Required.
Year: 1886

page_text: in Coiled or Partially Coiled Objects, or in some Cases where
a Brake is Required.
We, MATTHEW HENRY ROBOTTOM of Shustoke in the County of Warwick,
Watch Manufacturer, and JOHN HENRY BROUGH of Red Cross Street, Liverpool,
in the County of Lancaster, Merchant, do hereby declare the nature of this inven-
tion and in what manner the same is to be performed, to be particularly described
and ascertained in and by the following statement :---
Our invention is best described by its application to spring roller blinds as set
forth in accompanying drawings in which
Figure 1 is a front elevation.
Figure 2 an end elevation and
Figure 3 a longitudinal section.
In these A is the fixed spindle having squared half round or other non-cylindrical
ends held in suitably shaped brackets B at each end to ensure its not turning
round. C is the hollow blind roller having bearings D on spindle A, fastened at
one end to spindle A at (a) in any convenient manner but preferably by passing
through a hole therein, and to a point on the roller C at its other end is the usual
coiled spring E of the spring blind. On spindle A preferably at one end is the
barrel F carrying a coiled spring wire G. This is shown with only four revolutions,
but in practice we now prefer to put six or more revolutions as giving a firmer
grip; this spring with the exception of its last turn fits easily on the barrel at the
end (opposite e e) which turn is made slightly smaller in diameter than the
barrel, and so always has a tight grip on it. The end e projects upward through
slot K in barrel C. The other end h of the spring projects upward through a wide
aperture H in barrel C. The blind I is fastened to the barrel in the usual manner,
and has a heavy rod J. J at end to weight it down.
The mode of action is as follows:-
The blind being in the wound up condition and the spring little in compression
the weight J would pull it down if not prevented. The moment however the
pressure of this weight comes on the roller the clutch is tightened through the edge

page_text: of the slot K of the roller coming against end e of the wire clutch and tightening
up the coils of the spring till several are tight against the spindle like the single
coil next h. The friction caused by this tightening prevents movement on the
roller and further uncoiling of the blind but extra strain such as the pull of the
hand draws one more turn of the coil tight till the edge of the slot comes against
end h releasing the latter and relieving the strain. The barrel is thus free to
revolve and the blind runs down till the extra strain being removed the end h
again is free and allows the wire clutch to bind sufficiently to hold the roller and
stop the blind. To wind up the blind the weighted rod is lifted all strain is thus
taken off the wire clutch, and the internal spring E acting on the fixed spindle and
free barrel C rotates the latter, and at once winds the blind up.
Figures 4 and 5 show a slightly improved modification which we expect will
prove cheaper and better than our experimental kind above described. In these
pegs Hand K¹ fixed to the bearing take the place of the slots in the barrel and
the clutch is placed out of sight.
It is obvious that this clutch mechanism is applicable for almost any purpose
where anything requires to be capable of uncoiling at a given increment of strain
of stopping the moment that increment ceases to act, and of taking up the slack
and coiling up the moment the ordinary strain is removed.
Having now particularly described and ascertained the nature of our said
invention, and in what manner the same is to be performed, we declare that
what we claim is :-
:-
1st. The herein described appliances applicable to spring blinds, no claim being
made for the roller C, the stationary spindle A and bearings B and D taken
separately but only when combined with a blind and clutch arrangement, substan-
tially as described.
2nd. The mechanism for enabling a band, blind, line or other article required to
be coiled when there is little or no resisting strain on it-to stand stationary under
a given strain or range of strains uncoil under a still greater strain, and coil up
when such strains are almost or altogether removed, substantially as described.
3rd. The brake or holding apparatus consisting of a barrel, a coiled spring round
same with tight coil at one end, and one or more slack coils and with two pro-
jecting ends or handles, substantially as described.