Improvements in Safety Suspending Apparatus for Lifting and Lowering Gear, especially applicable to Window Blinds.
Year: 1897

page_text: Date of Application, 28th Sept., 1897-Accepted, 28th Oct., 1898
COMPLETE SPECIFICATION.
Improvements in Safety Suspending Apparatus for Lifting and
Lowering Gear, especially applicable to Window Blinds.
I, EDMUND FISHER HARTSHORN, of East Newark, County of Essex, State of
New Jersey, United States of America, Manufacturer, do hereby declare the nature
of my 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 those pulleys known as grip-pulleys, in which the cord
passing through the pulley is gripped and held whenever desired and prevented
from running over the pulley wheel, and which are used to lift various objects
and hold them suspended at any elevation.
My invention is especially designed for use with window shade fixtures having
spring rollers, where the rollers are placed at the bottom of the window casing,
and the free end of the shade is pulled up toward the top of the window, but is
also adapted for all other purposes.
In the accompanying drawing illustrating my improvement, Figure 1 is a side
view of the pulley in position showing the cord attached to the end of a window
shade mounted on a spring roller at the bottom of the window; Figure 2 is a front
view of the pulley, partly in section; Figure 3 is a side view of the pulley show-
ing the position of the parts when the cord is gripped; Figures 4, and 6 are views
of a modified construction of the pulley; and Figures 7 and 8 are further modifi-
cations of the same.
The pulley wheel a over which the cord runs is journaled and revolves in the
fixed support e, by which the pulley is secured in position. Mounted on the same
bearings in the support c is a swinging frame b, which encloses the wheel on both
sides and has a narrow bottom or cross-piece 6. In the normal position of the
pulley, in which the cord is not gripped but is free to run over the wheel in either
direction, this bottom piece hangs down between the two ends of the cord, as shown
in Figs. 1 and 2. The wheel and frame b are free to turn independently of each
other except as stated below. Mounted on the inner face of the frame b, above its
bearings, are pawls d, the toes or free ends of which are arranged and adapted to
drop down and engage with notches e¹, in the hub e of the disc or wheel h. When
this engagement of the pawl and hub is effected, as the pawl is on the swinging
frame and the hub on the disc, the frame and disc or wheel will be locked together,
and the continued revolution of the wheel will carry with it the frame and swing
the bottom piece b¹ in the direction of the arrow. The length of the frame is such
that when the bottom piece b¹ is swung upwards, it strikes against the plate of the
support as shown in Fig. 3, and the further revolution of the frame and conse-
quently of the wheel is stopped. To release the pawl from the hub, the wheel is
revolved slightly in the opposite direction when the toe of the pawl will be raised
from the notch, by the edge of the same engaging the underside of the said pawl,
the disengagement of the frame and wheel being thus effected.
The pawl is a gravity-pawl, and drops by its own weight into the notch on the
hub in effecting an engagement with the latter. This engagement of the pawl

page_text: with the notch can only take effect when the hub is revolved slowly, or at such
a rate of speed that the pawl has time to drop into the notch. If the hub is revolved
rapidly the pawl merely slides over the notch, and does not have time to drop into
the latter and effect an engagement.
The engagement of the pawl and hub is thus controlled by the speed of the
revolution of the hub: so long as the hub is made to revolve rapidly the pawl is
prevented from dropping into the notch, and effecting an engagement with the
hub; and on the contrary, when the speed of the hub is checked so that the latter
revolves slowly the pawl drops down into the notch, and the engagement of pawl
and hub is effected. To facilitate the passage of the pawl over the notch, and the
consequent non-engagement of the parts when the hub is rapidly revolved, the toe
of the pawl with respect to the shape of the notch is so constructed that it does not
readily catch in the latter.
Of course it will be understood that the hub is revolved in the direction in which
the engagement with the pawl is effected by the spring in the roller in winding
up the shade attached to the cord passing over the wheel. When the shade is per-
mitted to be run down, or wound up rapidly the wheel and hub are revolved so
fast, the pawl and notch cannot engage with each other, but if the movement of
the shade is checked at any point by means of the cord the pawl is allowed to drop
into the notch, engaging with the hub and locking the parts together, so that the
cord is secured and the end of the shade held up.
The wheel is thus, free to revolve without engagement with the frame b so long
as it is revolved rapidly, but the moment its speed is checked and it is made to
revolve slowly, the pawl at once drops down into and engages with the notch on
the hub, and the wheel and frame are locked and move together, and the frame is
turned until the bottom piece b¹ is brought into contact with the base plate of the
support c.
The operation of the pulley is as follows:
The end of the cord is attached to the shade or other object which it is desired
to raise and hold. By pulling on the opposite end g of the cord the shade is raised
to any desired point. If the end g of the cord is released so as to permit the shade
to run down, or wind up rapidly on the roller, under the action of the spring in
the latter, the wheel is revolved so quickly that the pawl does not engage with
the hub and the frame b remains stationary with the bottom piece b¹ down, as in
Fig. 1. The shade may thus be raised and lowered freely so long as the motion is
a rapid one, but the moment the downward motion of the shade is checked by hold-
ing the cord g, and hence the wheel caused to revolve slowly the pawl on the
frame engages with the hub on the wheel, locking the two together, and the
continued revolution of the wheel swings the frame around until the bottom piece b¹
is brought in contact with the plate of the support c. The cord is now as shown
in Fig. 3 tightly jammed between the edge of the bottom piece on the frame and
the plate of the support, and the tension of the cord under the action of the spring
in the roller, or of the weight of the object held, causes the bottom piece to press
firmly against the plate so that the cord is securely gripped and held, thus holding
the shade or other object up at any desired position. The cord is thus gripped
by the pressure of the bottom piece of the frame b against the window frame, and
as will be evident the greater the force of the spring in the roller tending to wind
up the shade, or of the weight of the object to be supported, the firmer the hold on
the cord and the grip of the pulley.
To release the grip of the pulley and free the cord, it is only necessary to pull
on the end g of the cord when the frame 6 will be turned back towards its normal
position thus allowing the cord to run over the wheel, and the wheel revolved
sufficiently to raise the pawl from its engagement with the notch on the hub, the
frame being thus disconnected from the wheel and the cord free to run through
the pulley at will to raise or lower the blind.
In the construction shown in Figures 1, 2, and 3 of the drawing, the pawls d
and hub e are enclosed in a frame h in engagement with the wheel a.

page_text: In the modified construction illustrated in Figs. 4 to 8 of the drawing, the cord
is gripped and held by the pulley-wheel, the rim or periphery of which is formed.
with a V-shaped channel, which is preferably serrated, as shown in Figs. 4 and 6,
to more securely hold the cord.
In the bottom of the frame b is a hole or opening 63 through which both ends
of the cord pass, and by means of which the cord is made to closely hug the
periphery of the wheel, and is thus prevented from slipping on the latter.
The pawls d Figs. 1, 4, 5 and 6 are respectively mounted on the side of the
frame b at a position slightly above and below the axis of the wheel a so that the
toes (of the pawls) will fall on and rest against the rim of the wheel; and in this
rim are the notches el with which the pawls engage. The engagement of the pawls.
and notches locks the wheel and prevents it from revolving in the direction of the
arrow, or in the direction to lower the article attached to the cord, and, as in this
construction, the cord is gripped and held by the wheel, and cannot slip over the
latter, when the wheel is held stationary by the pawl the cord is held and pre-
vented from passing through the pulley. The operation of this form of pulley is
the same as that previously described. When the wheel is revolved rapidly the
pawl passes over the notches and does not engage with the wheel, but as soon as the
revolution of the wheel in the direction to lower the shade or other article is
checked, the pawl enters the notch and stops the wheel and the cord is gripped, and
the shade, or other article held stationary. A slight movement of the wheel in
the opposite direction lifts the toe of the pawl out of the notch, and dis-
engages the wheel from the frame.
In the form of pulley shown in Figs. 4, 5 and 6, the frame b and wheel a are
both journaled in the fixed support c, so as to turn independently therein. This
adaptability of the frame b to turn in the support e enables the pulley to be
attached to the window casing or elsewhere in any position, and have the opening b
through which the cords pass always in line with the cords, as. when the shade
moves horizontally, and the pulley is attached as shown in dotted lines in Fig. 5.
In place of attaching the pawl on the frame b, the pawl may be mounted on the
support c, as shown in Fig. 7, and made to engage with the notches on the wheel a.
And furthermore the frame b may be connected directly to the window-casing
or elsewhere, and the support e dispensed with as in Fig. 8. In this case the wheel a
is journaled in the frame, and the pawl d is mounted on the frame and engages
with a notch on the hub or journal e, as in the construction shown in Fig. 1.
Having now particularly described and ascertained the nature of my said
invention, and in what manner the same is to be performed, I declare that what
I claim is
1. In a grip pulley, in combination, a wheel journaled in a fixed support; a
movable frame provided with a cross-piece arranged and adapted to confine the
cord when moved with the wheel; and a pawl or pawls mounted on the frame in.
position to engage with the wheel, whereby the wheel and frame are locked and
move together, the arrangement of the pawl or pawls and wheel being such that
they are brought into engagement by a slow motion, and held out of engagement
by a rapid motion of the wheel, substantially as described.
2. In a grip pulley, in combination, a wheel journaled in a fixed support, a frame
journaled in the support and provided with a cross-piece arranged and adapted to
grip the cord against the support when turning with the wheel; and a pawl or
pawls mounted on the frame in position to engage with the wheel, whereby the
frame and wheel are locked and move together, the arrangement of the pawl or
pawls and wheel being such that they are brought into engagement by a slow
motion, and held out of engagement by a rapid motion of the wheel, substantially
as described.
3. In a grip pulley, in combination, a fixed casing supporting the wheel, a wheel
journaled therein, a frame journaled in the casing so as to turn independent of the
wheel and provided with a cross-piece arranged and adapted to press and confine

page_text: the cord against the top of the casing; and a pawl or pawls mounted on the frame
in position to engage with the wheel, whereby the frame and wheel are locked
and move together, the arrangement of the pawl or pawls and wheel being such
that they are brought into engagement by a slow motion, and held out of engage-
ment by a rapid motion of the wheel, substantially as described. .
4. In a grip pulley, in combination, the casing c; wheel a journaled therein;
frame 6 journaled in the casing c, and having the cross-piece 61; pawl or pawls d
mounted on the frame, and notched hub e secured to the wheel a, the pawl or pawls
being arranged to engage with the notched hub under a slow revolution of the
wheel, whereby the frame and wheel are locked and turn together to grip the cord,
and to be held out of engagement by a rapid revolution of the wheel, substantially
as described.
5. As a new article, a grip-pulley comprising a wheel, arranged to receive and
hold a cord on its periphery; a frame enclosing the wheel and having an opening
through which both ends of the cord pass, whereby the cord is made to closely hug
the periphery of the wheel; and a pawl or pawls mounted in position to engage
with the wheel, the arrangement of the pawl and wheel being such that they are
brought into engagement by a slow motion, and held out of engagement by a rapid
motion of the wheel; and means whereby the frame is attached in position, sub-
stantially as described.
6. In a grip-pulley, in combination, a wheel adapted to grip and hold the cord;
a frame enclosing the wheel and having an opening for the cord, whereby the
cord is made to closely hug the periphery of the wheel; and a pawl or pawls
mounted in position to engage with the wheel, the arrangement of the pawl and
wheel being such that they are brought into engagement by a slow motion, and
held out of engagement by a rapid motion of the wheel, substantially as described.
7. In a grip-pulley, in combination, a wheel adapted to grip and hold the cord;
a frame arranged to be attached in position, a second frame journaled in the fixed
frame so as to turn therein, and enclosing the wheel and having an opening for
the cord whereby the cord is made to closely hug the periphery of the wheel; and
a pawl or pawls mounted in position to engage with the wheel, the arrangement
of the pawl or pawls and wheel being such that they are brought into engagement
by a slow motion, and held out of engagement by a rapid motion of the wheel, sub-
stantially as described.
8. In a grip-pulley, in combination, a wheel adapted to grip and hold the cord;
a frame arranged to be attached in position; a second frame journaled in the fixed
frame so as to turn therein, and enclosing the wheel and having an opening for
the cord whereby the cord is made to closely hug the periphery of the wheel; and
a pawl mounted on the movable frame in position to engage with the wheel, the
arrangement of the pawl and wheel being such that they are brought into engage-
ment by a slow motion and held out of engagement by a rapid motion of the wheel,
substantially as described.
9. In a grip-pulley, in combination, the wheel a adapted to grip and hold the
cord, and provided with notches for engagement with the pawl; frame c arranged
to be attached in position; frame 6 journaled in the frame h, and having the open-
ing 62 for the cord whereby the cord is made to closely hug the periphery of the
wheel; and the pawl d mounted on the frame 6 and arranged to engage with the
notches on the wheel as set forth, substantially as described.
Dated this 31st day of August 1897.
EDMUND FISHER HARTSHORN,
Haseltine, Lake & Co.,
45, Southampton Buildings, London, W.C.,
Agents for the Applicant.