IMPROVED CLUTCH MECHANISM
Year: 1879

page_text: LETTERS PATENT to John Clayton Mewburn, of 169, Fleet Street, in the City
"
of London, Patent Agent and Consulting Engineer, for the Invention of
IMPROVED CLUTCH MECHANISM." A communication from abroad by Thomas
Wells Capen, of Stamford, Connecticut, in the United States of America.
PROVISIONAL SPECIFICATION left by the said John Clayton Mewburn at
the Office of the Commissioners of Patents on the 20th March 1879.
JOHN CLAYTON MEWBURN, of 169, Fleet Street, in the City of London, Patent
Agent and Consulting Engineer. IMPROVED CLUTCH MECHANISM." [A com-
munication from abroad by Thomas Wells Capen, of Stamford, Connecticut, in the
United States of America.]
The main object of this Invention is to make cheap, simple, and effective
mechanism for operating friction clutches and other clutches used upon driving
shafts and gearing, an object which I attain by combining with the said clutches
certain toggle joint levers, and a sleeve encircling them, whereby the said levers and
clutches are operated as explained hereinafter.
The Invention has no relation to any peculiarity in the clutches themselves,
which may be common forked clutches, or claw clutches or ratchet clutches; or
they may be friction clutches having conical friction faces or disc surfaces, such as
described in the Specification of the Letters Patent granted to Thomas Aldridge
Weston, dated 29th January 1863, No. 263, or any other form of clutching device
whatever if operated by pressure applied in the direction of the shaft's length. The
positive action of this clutch-operating-device both ways, "on and off," or coupling
and uncoupling, is one of its characteristics; another one is that it produces no collar
friction or displacement of the shaft longitudinally, the strains being self con-
tained; another, and its distinctive advantage, is its extreme compactness and
freedom from projections; the toggle-lever system being of no larger diameter than
can be encircled within and passed over freely by the operating sleeve or sliding
collar which is grooved on its exterior, so as to be moved by the usual forked lever
commonly employed for throwing the clutches of shafting and gearing.
To illustrate the Invention I will describe it as employed to operate both or
either of two ordinary frictional cone clutches. In the enlarged portion of the

page_text: shaft between the two clutches is formed a longitudinal slot or recess, into which
projects a portion of the operating sleeve or sliding collar. This collar is arranged
to slide on the shaft, and is operated by the usual forked lever adapted to an
outside groove in the said collar in the ordinary manner, and the portion of the
sleeve or rib projecting from its inner surface into the slot in the shaft is made
adjustable by means of its attaching screws; and its longitudinal motion operates
the system of toggles and links beneath it in the slot, as will now be explained.
A short lever with its two equal arms inclined upwards and towards each other is
centred upon a pivot fixed transversely in the said slot or recess in the shaft. The
extremity of each lever arm is pivoted to a link, and each link at its further end is
pivoted to the hub or central boss of its adjacent friction cone. The said double
ended lever and two links together form a double toggle with one fixed centre on
the pivot of the lever, and two moving extremities attached one to each cone.
The pivots whereby each link is attached to its cone pass transversely across the
shaft in slots, permitting the pivots to move longitudinally in the shaft with their
respective cones upon the shaft. The bent-lever and links when in the middle or
neutral position form an inverted W of flat or open form, thus M, the mid portion
being the double armed lever with its fulcrum at the apex, the outer members or
limbs being the links. In the neutral position when neither cone is forced into its
clutched position the rib or inward projection of the sleeve or sliding collar is
central between the embracing arms of the bent lever or middle part of the
system M. By moving the rib (and collar) either way it rides over and depresses
one arm of the lever and its connected link, straightening them into a common line,
thereby forcing by toggle action the adjacent cone into the coupled or clutched
position. Simultaneously the other arm of the lever has been further elevated, the
angle between it and its link diminished, and its adjacent cone drawn still further
out of action. By reversing the motion of the rib and collar the cone last connected
or made to drive is uncoupled, and the free one clutched. By leaving the sleeve or
collar in the middle position both cone clutches are made free or disconnected.
If it is desired not to weaken the shaft by cutting therein a slot or recess to
receive the toggle system the shaft may be left whole, and the toggles sunk into a
sleeve or hub surrounding the shaft, and fixed thereto. In this case the toggles are
duplicated, and placed opposite to each other in the hub or fixed sleeve on opposite
sides of the shaft. If it is desired to operate a single clutch the toggle system will
consist of the bent lever and a single link, when as before the depression of one end
of the lever will apply the clutch, and the depression of the other will withdraw it.
Two clutches may also be operated by duplicating the last named modification, if so
arranged that the contiguous arms of the levers, that is to say, the arms having no
link attached, approach each other, so that the sliding collar may pass over all; and
by this construction one clutch may be operated and put in action or out without.
affecting the other, the toggles of the one being wholly separated or isolated from
those of the other clutch, although one sliding collar serves to operate both clutches.
when so desired.
For adjustment and compensation for wear I employ ordinary set screws.

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent filed by
the said John Clayton Mewburn in the Great Seal Patent Office on the
20th September 1879.
JOHN CLAYTON MEWBURN, of 169, Fleet Street, in the City of London, Patent
Agent and Consulting Engineer. "IMPROVED CLUTCH MECHANISM.” (A com-
munication from abroad by Thomas Wells Capen, of Stamford, Connecticut, in the
United States of America.)
The main object of this Invention is to make cheap, simple, and effective
mechanism for operating friction clutches and other clutches used upon driving
shafts and gearing, an object which I attain by combining with the said clutches
certain toggle joint levers, and a sleeve encircling them, whereby the said levers
and clutches are operated, as explained hereinafter.
દ્ર
The Invention has no relation to any peculiarity in the clutches themselves, which
may be common forked clutches, or claw clutches, or ratchet clutches; or they may
be friction clutches having conical. friction faces or disc surfaces, such as described
in the Specification of the Letters Patent granted to Thomas Aldridge Weston,
dated 29 January 1863, No. 263, or any other form of clutching device whatever
if operated by pressure applied in the direction of the shaft's length. The positive
action of this clutch operating device both ways, on and off," or coupling and
uncoupling, is one of its characteristics; another one is that it produces no collar
friction or displacement of the shaft longitudinally, the strains being self contained;
another, and its distinctive advantage, is its extreme compactness and freedom from
projections; the toggle lever system being of no larger diameter than can be
encircled within and passed over freely by the operating sleeve or sliding collar,
which is grooved on its exterior so as to be moved by the usual forked lever
commonly employed for throwing the clutches of shafting and gearing.
To illustrate the Invention I will describe it as employed to operate both or
either of two ordinary frictional cone clutches, and I will refer to the Figures of
the annexed Drawings.
In the enlarged portion a, Figure 1, of the shaft B, between the two clutches is
formed a longitudinal slot or recess m, into which projects an adjustable portion h
of the operating sleeve or sliding collar G. This collar is arranged to slide on the
shaft, and is operated by the usual forked lever adapted to an outside groove in the
said collar in the ordinary manner, and the portion of the sleeve or rib h projecting
from its inner surface into the slot on the shaft is made adjustable by means of its
attaching screws e, e, d'; and its longitudinal motion operates the system of toggles
and links beneath it in the slot, as will now be explained. A short lever H shown
separately in Figure 4 with its two equal arms I, I, inclined upwards, and towards
cach other, is centred upon a pivot f fixed transversely in the said slot or recess m
in the shaft. The extremity of each lever arm is povoted to a link u, and each
link at its further end is pivoted to the hub or central boss y, y¹, of its adjacent
friction cone D, D¹. The said double ended lever H and two links u together form
a double toggle with one fixed centre on the pivot f of the lever, and two moving
extremities, attached one to each cone. The pivots x, x, whereby each link is
attached to its cone pass transversely across the shaft in slots, permitting the pivots
to move longitudinally in the shaft with their respective cones upon the sbaft.
The bent lever and links when in the middle or neutral position form an
inverted W of flat or open form, thus M, the mid portion being the double armed
lever with its fulcrum at the inverted apex, the outer members or limbs being the
links u, u.
In the neutral position when neither cone is forced into its clutched
position the rib or inward projection h of the sleeve or sliding collar G is central

page_text: :
between the embracing arms of the bent lever H or middle part of the system M.
By moving the rib (and collar) either way it rides over and depresses one arm of
the lever and its connected link, straightening them into a common line, thereby
forcing by toggle action the adjacent cone into the coupled or clutched position.
Simultaneously the other arm of the lever has been further elevated, the angle
: between it and its link diminished, and its adjacent cone drawn still further out
of action. By reversing the motion of the rib and collar the cone last connected or
-made to drive is uncoupled, and the free one clutched. By leaving the sleeve or
- collar in the middle position both cone clutches are made free or disconnected.
The two pullies, wheels, or equivalent parts A, A¹, may thus be efficiently
connected with and disconnected from the shaft B, the shaft being either driven or
the driver, as required.
Figure 1 represents the cone D withdrawn and disengaged from the pulley A,
and the cone D' frictionally engaged with the pulley A¹; the toggle system and
sliding collar being in their corresponding positions obtained by the collar having
been moved to the end of its traverse in the direction of the arrow; Figure 2 is a
longitudinal view, partly sectional, taken at right angles to Figure 1; and Figure 3
is a transverse section of Figure 1 through the line 1, 2.
If it is desired not to weaken the shaft by cutting therein a slot or recess to
receive the toggle system, the modification shown in Figures 5 and 6 may be
employed; the shaft may thus be left whole, and the toggles sunk into a sleeve or
bub M surrounding the shaft, and fixed thereto by pins M¹. In this case the
toggles are duplicated and placed opposite to each other in the hub or fixed sleeve
on opposite sides of the shaft. If it is desired to operate a single clutch the toggle
system will consist of the bent lever and a single link, when, as before, the depression
of one end of the lever will apply the clutch, and the depression of the other will
withdraw it. Two clutches may also be operated by duplicating the last named
modification in the manner represented in Figures 7 and 8, if so arranged that the
contiguous arms of the levers, that is to say, the arms having no link attached,
approach each other, so that the sliding collar may pass over all, and by this con-
struction one clutch may be operated and put in action or out without affecting
the other; the toggles of the one being wholly separated or isolated from those of
the other clutch, although one sliding collar serves to operate both clutches when so
desired.
For adjustment and compensation for wear I employ an ordinary set screw
arrangement. Thus for Figure 1 the collars b, b, may be screw threaded upon the
shaft or upon a sleeve fixed to the shaft with the usual nut and jamb nut to
prevent looseness. For larger shafts and larger diameters in the parts A, D, A¹, D¹,
I prefer to attach a separate disc or face to the parts D, D¹, uniting them by
alternate pushing screws and pulling screws whereby the adjustment can be effected,
so that the compressing action of the toggles may occur at the desired point in the
motion of the sliding collar and with the desired force.
Although I have represented the Invention as applied to the operating of cone
clutches, it is obvious that it may be also applied to operate any other form of
clutch requiring like longitudinal motion and force in line with the shaft's length,
and with all the convenience and advantage according to the use of this Invention;
and although I have shown the Invention placed between the two clutches where
two are required, it may nevertheless be placed at the outer end of the shaft, and
the push and pull motion of the toggles transmitted to the clutches by a pushing
rod placed centrally within the shaft, or by sliding keys or bars sunk in the surface
of the said shaft, the said pushing rod or bars being attached to a sliding collar or
hub, between the clutches in a manner well known and obvious.
And having now described the nature of the said Invention, and in what manner
the same is to be performed, I declare that I claim,―
The improved clutch mechanism for operating clutches consisting essentially of a
system of toggles acting in the axial line of the shaft or parallel therewith, and an

page_text: operating collar or slide surrounding the same, substantially as hereinbefore
described and represented in the accompanying Drawings.
In witness whereof, I, the said John Clayton Mewburn, have hereunto set
my hand and seal, this Twentieth day of September, One thousand eight
hundred and seventy nine.
J. C. MEWBURN. (L.S.)