IMPROVEMENTS IN BREAK APPARATUS FOR RAILWAY AND OTHER CARRIAGES."
Year: 1880

page_text: LETTERS PATENT to Walter Parker Smith, of Lostwithiel, in the County of
Cornwall, for an Invention of "IMPROVEMENTS IN BREAK APPARATUS FOR
RAILWAY AND OTHER CARRIAGES."
0
PROVISIONAL SPECIFICATION left by the said Walter Parker Smith at the
Office of the Commissioners of Patents on the 31st January 1880.
WALTER PARKER SMITH, of Lostwithiel, in the County of Cornwall.
MENTS IN BREAK APPARATUS FOR RAILWAY AND OTHER CARRIAGES."
"
IMPROVE-
My Invention relates to means of working breaks of a railway or other
carriage from a running axle thereof. On the axle I fit a sleeve having a screw
thread cut on its external surface, and I fit this sleeve so as to run loose on the
axle, but provide it with a friction clutch whereby it can be caused to revolve with
the axle with more or less force as may be required according to the pressure
applied to the friction clutch. I arrange to slide parallel to the axle a block
containing a part nut, having a thread suited to that on the sleeve, and I provide a
cam whereby this part nut can be advanced to engage with the thread on the
sleeve, or retracted so as to be disengaged therefrom. To the sliding block in
which the nut is fitted I attach one end of a chain which passes between two guide
pullies mounted near the middle of the sleeve, and has its other end attached to the
break lever. When it is desired to put on the breaks the clutch is engaged so that
the screw sleeve is driven by the axle, and the part nut is engaged with the sleeve,
and thus, whether the axle be turning in the one direction or the other, the nut being
caused to travel along the sleeve from its middle position, the chain attached to it
is subjected to tension which is communicated to the break lever putting on the
breaks. For taking off the breaks the nut is disengaged and the friction clutch is
released, whereupon a weight or spring takes off the breaks and brings the nut
back to its middle position. I prefer to connect to the cam that moves the nut into
or out of gear a lever that moves the clutch so that the same action engages both,
but I arrange the cam with a dwell upon it so that after the nut is engaged the
continued movement of the cam has no effect in engaging the nut farther, but merely
serves to put greater pressure on the friction clutch, and thus by greater or less
movement of the cam the breaks can be applied with greater or less force as may be

page_text: desired. The engaging cam may be worked by the guard or official on each break
carriage separately, or the cams of the several break carriages throughout a train
may be connected in any known manner, as for continuous breaks. In such cases
the cams are arranged to be operated by weights or springs, so that when left free
they engage the clutch and nut automatically, and therefore in order to keep the
breaks off the cams must be held so as to keep the clutch and nut disengaged. In
case of accident to the train the force that retains the cams in opposition to their
weights or springs being removed the nuts and clutches become automatically
engaged and the breaks are put on.
SPECIFICATION in pursuance of the conditions of the Letters Patent filed
by the said Walter Parker Smith in the Great Seal Patent Office on the 27th
July 1880.
WALTER PARKER SMITH, of Lostwithiel, in the County of Cornwall. "IMPROVE
MENTS IN BREAK APPARATUS FOR RAILWAY AND OTHER CARRIAGES."
My Invention relates to means of working breaks of a railway or other carriage
from a running axle thereof. On the axle I fit a sleeve having a screw thread cut
on its external surface, and I fit this sleeve so as to run loose on the axle, but
provide it with a friction clutch whereby it can be caused to revolve with the axle
with more or less force as may be required according to the pressure applied to the
friction clutch. I arrange to slide parallel to the axle a block containing a part
nut, having a thread suited to that on the sleeve, and I provide a cam whereby
this part nut can be advanced to engage with the thread on the sleeve, or retracted
so as to be disengaged therefrom. To the sliding block in which the nut is fitted
I attach one end of a chain which passes between two guide pullies mounted near
the middle of the sleeve, and has its other end attached to the break lever. When
it is desired to put on the breaks the clutch is engaged so that the screw sleeve is
driven by the axle and the part nut is engaged with the sleeve, and thus, whether
the axle be turning in the one direction or the other, the nut being caused to travel
along the sleeve from its middle position, the chain attached to it is subjected to
tension which is communicated to the break lever, putting on the breaks. For
taking off the breaks the nut is disengaged and the friction clutch is released,
whereupon a weight or spring takes off the breaks and brings the nut back to its
middle position. prefer to connect to the cam that moves the nut into or out of
gear a lever that moves the clutch, so that the same action engages both, but I
arrange the cam with a dwell upon it so that after the nut is engaged the continued
movement of the cam has no effect in engaging the nut farther, but merely serves
to put greater pressure on the friction clutch, and thus by greater or less movement
of the cam the breaks can be applied with greater or less force as may be desired.
The engaging cam may be worked by the guard or official on each break carriage
separately, or the cams of the several break carriages throughout a train may be
connected in any known manner as for continuous breaks. In such cases the cains

page_text: are arranged to be operated by weights or springs, so that when left free they
engage the clutch and nut automatically, and therefore in order to keep the breaks
off the cams must be held so as to keep the clutch and nut disengaged. In case of
accident to the train the force that retains the cams in opposition to their weights
or springs being removed the nuts and clutches become automatically engaged and
the breaks are put on.
DESCRIPTION OF THE DRAWINGS.
Fig. 1 is a front elevation, Fig. 2 a side elevation, and Fig. 3 a plan of break
apparatus according to my Invention; Figs. 4, 5, 6, 7, and 8 are transverse sections
respectively, on the lines X, Y, Z, W, and V, of Fig. 1; and Fig. 9 is a longitudinal
section of part of the axle and its attachments at W. In all those Figures the same
parts are marked with similar reference letters. A is one of the running axles of a
railway carriage, about the middle of which is fitted loosely a sleeve B having a
screw thread cut on its exterior. The sleeve B is kept from sliding towards the
right by a ring P clamped on the axle, and it extends towards the left till it
terminates in 4 key shaped segments, fitting in the conical casing of a cone C
which is keyed on the axle A. At the side of the conical casing there is a ring D
and also a ring E, both of which are free to revolve round the sleeve B, but the
ring D is prevented from revolving by a notch in it engaging with a bar J of
the stationary framing of the apparatus. The ring E has projecting from it a
lever arm which is connected by a spring to a weight T that is suspended
from an arm S projecting from a spindle R. The ring E has also part of its
periphery toothed to gear with a pinion M on a spindle N. The meeting
faces of the rings D and E are formed with inclined clutch teeth, so that when
the arm of E is allowed to move downwards in obedience to the weight T
the ring D is by the obliquity of the clutch teeth pushed towards the left, and
thus the conical casing is pushed on to the cone C and caused by the frictional
contact to revolve with it. The spindle N is mounted in a framing J, which
has bearings I enclosing the sleeve B, and has arms Q projecting upwards into
slots in the frame g of the carriage. These arms Q being free to move up or down
in the slots allow the carriage frame to oscillate relatively to the axle A, but they
prevent the framing J from turning round the axle. A sliding block H is fitted to
enclose the sleeve B and the spindle N, and within this block is fitted to side
vertically a part nut G, which has a cam slot in which works a roller mounted on.
an arm O which is keyed on the spindle N. Thus when the spindle N is turned
partly round in one direction the roller working in the cam slot pushes up the part
nut G so that it engages with the screw thread of the sleeve B, and when N is
turned in the opposite direction the part nut G is retracted and disengaged from
the screw thread of B. To the block H are connected arins of levers K that work
in guides L attached to the framing J. Other arms of the levers K are connected
by bolts U to bars V, which are attached to the break levers. The bolts U being
free to be pushed through holes in the bars V but having on them nuts which
prevent thein from being drawn through these holes, operate on the bars V only
when they are pulled. The spindle R extends along the vehicle and has on it at
convenient places arms by which it can be turned partly round either by the action
of an attendant on each carriage or by a cord or other suitable connection from
carriage to carriage of a train, as is usually arranged for continuous breaks. As the
arms S of the spindles R are loaded by the weights T whenever the spindles R are
left free either purposely or by the accidental fracture of the connections which
retain them in their normal position, the arms S descend in obedience to the
weights T and cause the breaks to be applied, as I will now describe. By the
descent of the weight T the arm of the ring E is made to descend, turning E partly
round to a position such as is shown in Fig. 6.
ring E two actions are produced; first, by the
the ring D is pushed to the left, and thus the
From this partial rotation of the
action of the inclined clutch teeth
conical casing is engaged with the

page_text: cone C, so that the sleeve B which is keyed to the conical casing is caused to revolve
along with the axle; secondly, the toothed gearing on E causes the pinion M and
its spindle N to turn partly round, and thus the arm O is made to push the part
nut G in gear with the screw thread on B. As B is now revolving while the nut G
is engaged with it the sliding block H is caused to move to the right or to the left,
according as the axle A is revolving in the one direction or the other. By this
lateral movement of the block H the levers K are moved on their fulera, and thus
one or other of the bolts U linked to each of these levers is drawn, and the bars V
are consequently pulled upon and through them, the break levers causing the breaks
to be applied. The force with which they are applied will depend on the frictional
hold of the casing and cone C operating as a friction clutch for driving B, and as
the casing will be pressed more forcibly on the cone the farther the arm of the
ring E is permitted to descend, so by more or less movement of the spindle R
allowing greater or less descent of the arm E the break will be applied with more or
less force. To permit this variation in the movement of the ring E, which necessarily
varies the motion of the pinion M and its spindle N, the cam slot in the part nut Ġ
is made, as shewn in Fig. 7, with its first part nearly straight and the rest of it a
circular arc struck from the centre of N. As the arm O turns round that centre
the first part of its movement acting in the straight part of the slot serves to
engage the part nut with the screw thread of B, but during the rest of its move-
ment there is merely a dwell, retaining the nut engaged but not forcing it farther
into gear. Thus after the nut is engaged by the first part of the descending move-
ment of the arm of E the farther descent of that arm to increase the break force does
not affect the engagement of the screw threads. For the purpose of taking off the
breaks the spindle R is turned so as to raise its arm S. The ring E being thus
turned backwards permits the release of the cone clutch C, and disengages the
nut G from B, and the breaks being retracted by a weight or spring in the usual
way the bolts U, levers K, and sliding block H are restored to their normal
condition.
Having thus described the nature of my Invention, and in what manner the same
is to be performed, I claim,-
The use of break apparatus for railway and other carriages wherein a screwed
sleeve is caused by a friction clutch to revolve with a running axle, and a part nut
is simultaneously engaged with the sleeve, so that by the action of the screw and nut
lateral motion is given to a sliding block connected to the break levers, whereby
the breaks are applied, substantially as herein described.
In witness whereof, I, the said Walter Parker Smith, have hereunto set my
hand and seal, this Twentieth day of July, in the year of our Lord One
thousand eight hundred and eighty.
WALTER PARKER SMITH. (LS.)