Improvements in Rack-pulleys for Window-blinds.
Year: 1890

page_text: Date of Application, 18th Oct., 1890-Accepted, 22nd Nov., 1890
COMPLETE SPECIFICATION.
Improvements in Rack-pulleys for Window-blinds.
I, JOHN EDWARD LAMBERT of 75 Spring Gardens, Buxton, Derbyshire, Iron-
monger 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 :-
The improvements relate to what are known as rack pulleys for window blinds,
and have for object greater facility and certainty in use than at present obtains.
To accomplish this and to effect my improvements, I form a rack pulley frame in
form similar to the ordinary; but with a slot or groove cut or otherwise prepared
along its length. In this slot or groove the pulley carrier is made capable of sliding
up and down, and is provided with a screw, having a milled or other head, for securing
the carrier at any desired height in the slot or groove.
By preference I mount the pulley wheel in the same plane as the pulley on the
blind roller, instead of at right angles thereto as is mostly the case at present, and
thus prevent the half twist usually put upon the blind cord; but a pulley carrier may
be employed having a pulley mounted in any plane desired.
But that the improvements may be better understood I will by the aid of the
accompanying drawings, proceed more fully to describe means employed by me.
DESCRIPTION OF DRAWINGS.
Fig. 1 shews a front elevation; Fig. 2 a side elevation and Fig. 3 a longitudinal
section of a rack pulley arranged in accordance with my invention.
The same letters indicate corresponding parts wherever they occur.
a. a. is the rack pulley frame, b. b. is the pulley carrier, and c. c. the pulley
wheel. d. d. is the headed screw for holding the pulley carrier in position and which
is effected, in the case shewn, by means of the sliding nut e. e. at the back of the
frame.
In this example the pulley carrier is formed to clip the frame to form a slide, and
the screw passes through the tail of the carrier into the nut at the back for pinching
the carrier securely in position; but instead of a slot, a dovetailed groove can be
employed in which the carrier is fitted to slide and the screw will then hold the
carrier in position by compression, being resisted by the back of the frame, not passing
through the same.
Other variations in detail may also be made; as for example, in the shape of the
rack pulley frame; the angle at which the pulley is mounted; and in the application
of the screw; without departing from the peculiar character of the invention.
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 combination of a slotted or grooved rack pulley frame a, a, with a pulley
carrier b, b, sliding thereon or therein, and held in position by a screw d, d, for the
purpose and in manner substantially as herein shewn and described.
Dated this 16th day of Antah 1000
WILLIAM GADD, C.E.,
64, Barton Arcade, Manchester, Agent.
WILLIAM GADD, C.E.,
64, Barton Arcade, Manchester, Agent.