Improvements in Band or Rope Pulleys for Various Purposes.
Year: 1894

page_text: Date of Application, 22nd Nov., 1894
Complete Specification Left, 22nd Aug., 1895-Accepted, 19th Oct., 1805
PROVISIONAL SPECIFICATION.
Improvements in Band or Rope Pulleys for Various Purposes.
I, Alfred TraFFORD, of Wylde Green, near the City of Birmingham,
Engineer, do hereby declare the nature of this invention to be as follows:—
This invention relates to improvements in the contact peripheries of driven,
driving and paying-out pulleys, and has for its object, an automatic grip upon the
rope, band or motion-transmitting medium.
Thus, according to my invention, I provide or fit the contact periphery of a
pulley with a series of automatic grippers, which consecutively seize and hold the
rope or band when travelling in communicating motion from one pulley to another.
By the employment of self-tightening grips, no slipping of the rope or band
during its traverse is possible, hence a certain motion transmitter.
In carrying out one form of my invention, I take a sheave pulley, or a pulley
grooved or channelled upon its periphery, and fit upon the two opposite sides of
the bottom of the channel, a series of pairs of grippers, each pair consisting of two
gripping springs, made somewhat of the figure of a bell-cranked lever, with outward
bearing ends or parts, and with the said bearing end parts presented to each other,
and embracing a part of a circle, but with the outer tips of the said bearing parts
being normally separated from each other by a space a little greater than the
diameter of the rope or band to be gripped, whilst their inner tips come nearly
together and their attachment ends are preferably made fast to the two opposite
lower parts of the groove, so that on the band or rope being brought taut and the
nominal distance between the extreme opposite points of grip of two pulleys being
shortened, the said grips are turned inwards, and the distance between their
bearings or contacts is diminished, hence a band or rope is nipped and firmly held
between them.
As the motion of the pulley continues, the band is released from a first pair of
grips and is taken hold of by the next pair and so on consecutively through the
whole series, as they come adjacent to the extreme opposite points of grips of the
pulleys.
As a further form of my invention, instead of employing spring arm grippers, I
employ pawl-like grippers, mounted obliquely, and with their inner ends jointed to
the pulley or to the sides of the bottom of the channel of the pulley, which may
have a bottom clearance, to admit of the free movement of the gripping arms, jaws
or their equivalents.
Now as these pairs of gripping arms are set a little above the horizontal plane,
the bringing of the same towards a horizontal makes their gripping ends approach
each other, and between which ends, a band or rope is gripped on taut being put
thereon, and so motion is transmitted as effectively as if toothed pulleys and drive
chain were employed.
I propose that the mouths or entrances to the grooves or pulleys should be
provided with eaves or overhanging and downwardly inclined ledges.
The seatings at the gripping ends of the grippers may be concaved, V-ed or of
any other shape as desired.
As a still further form, I may connect each pair of the jointed or spring
grippers by a jointed tie, upon which the pressure of the band cord or rope

page_text: comes, and so closes or brings the grippers together upon the opposite sides of
the rope or cord.
Dated this 21st day of November 1894.
ALFRED TRAFFORD,
By Henry Skerrett,
6 Livery Street, Birmingham, Agent for Applicant.
Improvements in Band or Rope Pulleys for Various Purposes.
I, ALFRED TRAFFORD, of Wylde Green, near the City of Birmingham,
Engineer, do hereby declare the nature of this invention and in what manuer
the same is to be performed, to be particularly described and ascertained in and
by the following statement:-
This invention relates to improvements in the contact peripheries of driven,
driving and paying-out pulleys, and has for its object, an automatic grip upon the
rope, band or motion-transmitting medium.
Thus, according to my invention, I provide or fit the contact periphery of a
pulley with a series of automatic grippers, which consecutively seize and hold the
rope or band when travelling in communicating motion from one pulley to another.
By the employment of self-tightening grips, no slipping of the rope or band
during its traverse is possible, hence a positive motion transmitter.
In carrying out one form of my invention, I take a sheave pulley, or a pulley
grooved or channelled upon its periphery, and fit upon the two opposite sides of
the bottom of the channel, a series of pairs of grippers, each pair consisting of two
gripping springs, and with each spring made somewhat of the figure of a bell-
cranked lever, with outward bearing ends or parts, and with the said bearing end
parts presented to each other, and embracing a part of a circle, but with the outer
tips of the said bearing parts being normally separated from each other by a space
a little greater than the diameter of the rope or band to be gripped, whilst their
inner tips come nearly together and with their attachment or rest parts secured to
the pulley so that on the band or rope being brought taut and the nominal
distance between the extreme opposite points of grip of two pulleys being
shortened, the said grips are turned inwards, and the distance between their
bearings or contacts is diminished, hence a band or rope is nipped and firmly held
between them.
As the motion of the pulley continues, the band is released from a first pair of
grips and is taken hold of by the next pair and so on consecutively through the
whole series, as they come adjacent to the extreme opposite points of grips of the
pulleys.
Figure 1 of the accompanying drawing represents partly in elevation and partly
in vertical section, a pulley, with its periphery provided with self acting spring arm
grippers made according to one form of my improvements.
Figure 2 represents a vertical transverse section of the same on the dotted
lines Figure 1 and showing the dispositions of the nipping arms of the
grippers.
Figure 3 represents a transverse section of a part of the periphery of the pulley
upon a large scale, with the motion transmitting rope or band shown just in the act
of passing to the levering arms which when compressed closes the tips or horns
upon the rope, hence the gripping.
Figure 4 represents a like view as Figure 3, but with the rope or motion
transmitting band shown gripped.

page_text: a is a sheave or groove pulley, with the annular sinking a¹, fitted or provided
with a series of automatic grippers b, consisting of levering sides b', each made up
of piloting horns or tips 62, spring levering curved arm 63, and inner pressure
arms 6, and with the arms 63 jointed together by bottom parts 6 and secured to
the pulley by rivets 66. c is the motion transmitting band or cord and when
driving or when taut, the pressure arms are forced inwards and by the downward
and angular movements made by them the bends of the levering arms 63 are
contracted, and the horns or outer tips approach each other or close upon the
opposite sides of the band as represented in Figure 4, hence the gripping and
holding of it, during the period that the pulley is moving through a distance equal
to the distance between each of the grippers.
Immediately the pulleys have passed beyond the centre of motion, then the
grippers release their hold upon the band and automatically open out again into
the position as represented in Figures 1, 2 and 3.
Figure 5 represents a further form of gripper constructed according to another
form of my improvements.
a is the pulley, a¹ the annular groove in its periphery, b are a pair of grippers
each side consisting of a bell cranked lever ', jointed at to a lug or equivalent a²
on the inside of the pulley, and with the upright arm 2 adapted to be forced
inwards on the pressure of the band or rope coming upon the lower or pressure
arm 4, between which and the bottom of the pulley, a spring d is located. c is the
band, cord or rope of a circular section, although other sections may be employed.
On the band running taut between two such pulleys, the levers are turned upon
their fulcra, and their upper arms turned inwards upon the band, which is
consecutively gripped by each of the grippers as the rotation proceeds.
Figure 6 represents a still further form of gripper, constructed according to
another form of my invention.
b is the gripper, composed of levering sides b', each having levering arms b³, and
jointed at 6, and linked together at 6, and also with the lower ends of the said
arms, jointed at 610, to a spring base ", which is secured to the pulley by rivets or
other means b¹².
As a further form of my invention, instead of employing spring arm grippers,
I employ pawl-like jaws mounted obliquely, and with their inner ends jointed to the
pulley or to the sides of the bottom of the channel of the pulley, which may have
a bottom clearance, to admit of the free movement of the gripping arms, jaws or
their equivalents.
Now as these pairs of gripping arms are set slightly upwards and a little out of
the horizontal plane, the bringing of the same nearly lignable makes their gripping
ends approach each other, and between which ends, a band or rope is gripped on
taut being put thereon, and so motion is transmitted as effectively as if two toothed
wheels and drive chain were employed, but with a much smoother action.
Figure 7 represents a transverse vertical section of a self acting grip as last
described.
a is a pulley, having an inside grooved periphery a¹ and fitted with a series of
pairs of automatic grips b, consisting of jaws b', having gripping inner ends 62,
jointed at 63, and being disposed slightly upwards and obliquely to the horizontal
plane, so that on a band running over the peripheries of such pulleys, the said jaws
are drawn inwards and their acting gripping faces 62 made to approach each other,
and by the diminution of the distance between them, the band or rope c, for
transmitting motion between one pulley and another is thereby gripped. To bring
the jaws or gripping levers back to their normal positions, a spring 6", is located
between the heels of the said jaws and the pulley.
Figure 8 represents a modification of Figure 7.
a is the pulley, a¹ the annular groove, fitted with a series of pairs of automatic
grippers b, each gripper consisting of an arm b', with the inner end jointed at 6³, to
the pulley a, and with the other or gripping end 62, formed with a sealing, so that
when the arms which are disposed obliquely to a horizontal plane are drawn in by

page_text: the pull of the band, the said band which is marked c is nipped between the opposed
gripping faces of the levers, consequent upon the said gripping faces coming nearer
together on the levers approaching a straight line.
I might add that the heels of the levers have springs 610, for taking the arms
back to their normal positions, after the pulley or pulleys have passed their line of
grip.
Figure 9 represents a still further form of my improvements.
a is the pulley, b is a series of automatic grippers, consisting of a pair of levering
arms b', with attachment ends & secured to the insides of the pulleys whilst a³ are
eaves or guides for directing the band c to the pulley.
Figure 10 represents another form of grip constructed according to a further
form of my improvements.
a is the pulley, b is the grip, composed of levering arms 6', jointed at 62, with the
upper arms ³ constituting the gripping arms, and the inner arms & constituting the
closing arms which pass over a pin or a spring pin d, so that when the band c pulls,
the is drawn inwards and by the arnis 64 sliding over the pin d, the other
armis are closed upon the band c which is thereby gripped.
с
Immediately the grip has passed the line of grip of the pulley, then the gripper
relaxes its grip and resumes its normal state, with the tips of the same coming
against the overhanging shoulders or flanges a², which prevents them leaving the
pulleys.
Figure 11 represents a still further form of my improvements.
a is the pulley, 6 the grip, with a pair of spring levering arms 6', made of the
figure of a wedge with the lower part 2, passing through a hole a² in the pulley or
equivalent so that on the pull coming upon the band c, the grip is bodily moved
inwards and by the sides being forced through the hole a², the spring arms bare
closed upon the band c, hence the gripping and holding of it, until the same has
passed the line of grip.
I propose that the mouths or entrances to the grooves or pulleys should be
provided with eaves or overhanging and downwardly inclined ledges.
The seatings at the gripping ends of the grippers may be concaved, V-ed or of
any other shape as desired."
Although I have represented the grippers as being fitted within grooves, yet they
may with like effect be carried upon plain peripheries.
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 :-
First. Providing pulleys with a series of automatic grippers or a series of pairs
of automatic grippers, each side consisting of spring levering arms, drawn together
in the way substantially as and for the purpose as described and set forth in
Figures 1 to 4.
Secondly. Providing pulleys with a series of pairs of automatic grippers, each
side consisting of a jointed arm or lever arranged and operating in the way, and for
the purpose substantially as described and set forth in Figure 5.
Thirdly. Providing pulleys with a series of pairs of automatic grippers, each
grip consisting of jointed together arms or levers, arranged in the way and for the
purpose, substantially as described and set forth in Figure 6.
Fourthly. Providing pulleys with a series of pairs of automatic grippers, each
grip composed of a pair of closing jaws, substantially as and for the purpose
described and set forth in Figures 7, 8 and 9.
Fifthly. Providing pulleys with a series of pairs of automatic grippers, each
grip made up of a pair of jaws or levers which are constructed arranged and
operate in the way and for the purpose as described and set forth in Figure 10.
Sixthly. Providing pulleys with a series of pairs of automatic grippers, each
grip made up of a pair of arms or levering arms drawn together in the way and for
the purpose substantially as described and set forth in Figure 11.

page_text: Seventhly. In pulleys for transmitting motion, the general construction,
arrangement and combination of the parts, substantially as described and
set forth.
01
J
1005
ALFRED TRAFFORD,
By Henry Skerrett,
24 Temple Row, Birmingham, Agent for Applicant..