IMPROVEMENTS IN APPARATUS FOR RETARDING AND RESTARTING TRAMWAY AND OTHER CARRIAGES
Year: 1877

page_text: LETTERS PATENT to Laurence Hill, of Glasgow, in the County of Lanark, North
Britain, Civil Engineer, for the Invention of "IMPROVEMENTS IN APPARATUS
FOR RETARDING AND RESTARTING TRAMWAY AND OTHER CARRIAGES."
Sealed the 6th October 1877, and dated the 11th April 1877.
PROVISIONAL SPECIFICATION left by the said Laurence Hill at the Office
of the Commissioners of Patents on the 11th April 1877.
LAURENCE HILL, of Glasgow, in the County of Lanark, North Britain, Civil
Engineer. "IMPROVEMENTS IN APPARATUS FOR RETARDING AND RESTARTING
TRAMWAY AND OTHER CARRIAGES."
This Invention has for its object to utilise the power or part of the power at
present absorbed in friction when brakes are applied to the wheels of tramway and
other carriages for stoppages, in restarting or facilitating the restarting of such
carriages, and comprises improved and simple apparatus which can be very easily
manipulated by the driver, and which is specially suited for tramway cars that run
sometimes with one end and sometimes with the other end foremost.
In one modification of the improved apparatus there is fixed or formed on each
of two of the wheels on opposite sides of the car a pulley rim, having in connection
with it a lever or disc centered on the axle and fitted with a frictional gripper of
a kind used in windlasses and in feed mechanism of sawing and other machinery,
and which grips or engages with the pulley when moving in one direction relatively
to the pulley but which is quite free when the relative motion is reversed. The
grippers of the two levers are arranged reversely as regards each other, and the levers
are connected to opposite ends of a lever moving in a horizontal plane upon a
centre pin fixed to the car framing, and having a spring or springs applied to it. The
grippers are connected to hand levers at opposite ends of the car, but only that
one is in use which is at the end of the car running foremost at the time, and a
Bingle handle may be used for the two levers, the driver taking it to either end as
required, and leaving the lever at the other end so that it cannot be tampered
with. When the car is running, the lever at the driver's end is held in a notch,
and by its connection prevents the gripper on one side from engaging with the

page_text: wheel although the motion of the wheel is then in the direction for gripping whilst
the other gripper is then free in every way, the wheel motion not being in the
direction to cause it to grip. On stopping the car the driver simply releases the
lever from the catch, whereupon a spring or weight makes the gripper engage and
the motion of the wheel causes the horizontal lever to turn and strain the spring or
springs connected to it, the increasing strain of the spring or springs ultimately
stopping the wheel. When restarting the car the driver moves back the lever to
its notch, which causes the gripper through which the spring has just been strained
to be released, and the horizontal lever then acts on the other gripper in a direction
for making it engage with its wheel and drive it forward with the force stored in
the spring or springs.
The essential feature of the Invention is the adaptation of the reversely acting
grippers, clutches, or equivalent devices, so as on the spring or springs reacting
to propel the carriage in the same direction as that in which it moved before the
stoppage, this combination of reversed grippers or the like being also suitable for
the running of the carriage with either end foremost..
SPECIFICATION in pursuance of the conditions of the Letters Patent filed by
the said Laurence Hill in the Great Seal Patent Office on the 10th October
1877.
LAURENCE HILL, of Glasgow, in the County of Lanark, North Britain, Civil
Engineer. "IMPROVEMENTS IN APPARATUS FOR RETARDING AND RESTARTING
TRAMWAY AND OTHER CARRIAGES."
My said Invention relates to improved and extremely simple apparatus for
utilizing the power or part of the power ordinarily absorbed in friction, when
brakes are applied to the wheels of tramway and other carriages for stoppages,
in restarting or facilitating the restarting of such carriages. My improved apparatus
can be very easily manipulated by the driver and is specially suited for tramway
cars, which run sometimes with one end and sometimes with the other end
foremost.
The essential feature of my Invention is the adaptation of reversely acting
grippers directly and without toothed gearing to the carriago wheels or axles, so
as on stopping the carriage to strain a spring or springs which on the carriage
being restarted react and propel the carriage in the same direction as that in which
it moved before the stoppage, the combination of reversed grippers being also
suitable for the running of the carriage with either end foremost.
And in order that my said Invention and the manner of performing the same
may be properly understood, I hereunto append a Sheet of explanatory Drawings
to be herein-after referred to, and representing two modifications of my improved
apparatus; in these Drawings the same reference numerals are used to mark the
same or like parts wherever they are repeated.
Figure 1 on the accompanying Sheet of Drawings is a plan, showing part of the
franing of a tramway car, with the two pairs of wheels, and with one modification
of my improved retarding and restarting apparatus; Figures 2 and 3 are longi-
tudinal and transverse vertical sections, corresponding to Figure 1, and Figure 4 is
an enlarged sectional detail of one of the grippers.
Figures 5 and 6 are longitudinal and transverse vertical sections, showing a
second modification of my improved apparatus.
In the first modification, Figures 1 to 4, the apparatus is applied to two
wheels 7, 8, on the same axle 9, and the parts are shown in the positions they have
when the car is being drawn in the direction of the arrow. Each wheel 7, 8, has
formed or fixed on it a cylindrical flange or rim 10, or this rim 10 might be that
of a separato pulley fixed on the axle 0. Centered loosely on the axlo 9 there is

page_text: near each flange or rim 10 a lever or radius piece 11, which serves for keeping the
gripping mechanism at a proper distance from the axle; and at one end of each
radius piece 11 there is fixed a stud or bolt 12, on which there is centered a
gripping piece or gripper 13, made with an eccentric convexity on the side facing
the outer surface of the flange 10. The outer part of the gripper 13 has jointed
to it one end of a rod 14, the other end of which is jointed to a horizontal lever 15,
centered on a stud 16, fixed at the centre of the car framing on a transverse frame
piece 17. The rods 14 from the grippers of the two wheels 7, 8, are connected to
the opposite ends of the horizontal lever 15, and this lever is connected by one or
more springs 18 to the car framing. In Figure 2 it is the inner side of one 7 of
the wheels which is shown, and the radius piece 11, gripper 13, and other parts
appertaining to that wheel are shown in full lines, whilst the corresponding parts
appertaining to the other wheel 8 are shown in dotted lines. Each gripper 13 has
a curved lever 19 fixed to it by means of the centre bolt 12, and the bolt forming
the joint between the grippor 13 and rod 14. The curved lever 19 for the wheel 7
is connected by a rod 20 to a hand lever 21, centered on a bracket at the nearer
end of the car, and this lever 21 has a spring 22 applied to it which tends to move
its lower end outwards, but which cannot act with the parts in the position
delineated because of the lever being set in a lateral notch at the outer end of a
slotted catch plate 23 fixed to the car framing; the curved lever 19 for the other
wheel 8 is similarly connected by a rod 24 to a hand lever 25 at the other end of
the car, this second hand lever 25 being also acted on by a spring 20, whilst a
catch plate 27 is provided in connection with it.
The gripper 13 of the right hand wheel 7 is set, as shown in Figure 4, with the
eccentricity of its bottom convex part increasing towards the middle of the car,
and so that if the flange 10 in turning in the direction of the arrow wore in contact
with the gripper the motion and friction would tend to turn the gripper so as to
bear more on the flange and increase the grip. The gripper 13 is however held
just clear of the flange 10 in consequence of the hand lever 21 being held in the
position in which it is shown; the gripper 13 of the other or left-hand wheel 8 is
set in the reverse position, and the turning of the flange 10 in the direction of the
arrow in Figure 4 tends to move the gripper, if the flange touches it at all, in a
direction to prevent any grip.
It follows from the preceding explanation that, with the parts in the positions
in which they are shown in Figures 1 and 2, the car can proceed in the direction
of the arrows without the wheels 7, 8, acting on or being acted on by the
grippers 13 and mechanism connected therewith. When the driver is about to stop
the car he releases the hand lever 21, which being moved by the spring 22 causes
gripper 13 to engage with the flange 10 of the right-hand wheel 7, and the
rotation of the wheel carries round the gripper 13, and through the connecting
rod 14 turns the horizontal lever 15 so as to strain the spring or springs 18, the
increasing strain of which ultimately stops the motion of the wheel. The other
end of the horizontal lever 15 at the same time moves the gripper 13 of the left-
hand wheel 8 over, but without making it act on that wheel. On restarting, the
driver moves forward the hand lever 21, replacing it in its outer catch, and this
action releases the gripper of the right-hand wheel 7. The reaction of the spring
or springs 18 then takes effect upon the lever 15, and through it moves the
grippers 13 of both wheels 7, 8, back to their former positions; the gripper 13 of
the right-hand wheel 7 does not then act on that wheel, but the reversed position
of the other gripper causes it to act on the left-hand wheel S and turn that wheel
so as to propel the carriage in the direction of the arrow, that is, the same direction
as that of its motion before being stopped. Before replacing the hand lever 21 in
its outer holding catch the reaction of the spring or springs 18 could not operate,
because through the reversed actions of the opposite ends of the lever 15 its
tendency was to turn the wheels 7, 8, in opposite directions.
When the car is to run in the opposite direction to that indicated by the arrows,
the driver has simply to manipulate the other hand lever 25 at what will then be

page_text: the forward end of the car; a single handle 28 is by preference used for the two
hand levers 21, 25, the driver taking it to either end of the car, as required, and
leaving the lever at the other end so that it cannot be easily tampered with. It
is the removable handle 28 which engages with the notch of the plate 23 or 27,
and when the driver withdraws the handle at either end he necessarily leaves the
lever 21 or 25 at that end free as it ought to be when the lever at the other and
is the one in usc.
In the modification shown in Figures 5 and 6 the mechanism is applied to two
wheels 7, 8, on the same side of the car instead of being applied to wheels on
opposite sides of the car as in the first modification, and the reversing action
obtained in the former case by means of the horizontal lever 15 is in this second
modification got by connecting the lower end of one radius piece or lever 11 to the
upper end of the other one by a curved rod. The springs 18 are applied directly
to the upper ends of both radius pieces or levers 11, either connecting one to the
other or connecting each to a part of the car framing.
The levers 10 fixed to the grippers 13 are curved, as shown, in order that their
points of connection with the rods 20, 24, may be below the axle or axles, an
arrangement which renders the extent of movement of the hand levers 21, 25, much
less than it would be if the points of connection were above the axle or axles.
The immediate mechanism for gripping or engaging with the flanges 10 of the
wheels 7, 8, may be arranged or constructed in any suitable known manner. The
radius pieces 11 are shown as made with flanges 20 in contact, or nearly in contact,
with the insides of the wheel flanges 10, and the radius pieces may be mounted on
the axle or axles with a very slight play, sufficient to allow of the flanges 10 being
gripped between the grippers 13 and the flanges 29; or pairs of grippers may be
used with eccentric gripping surfaces, and acting one of each pair on the outside
of the wheel flange 10 and the other on the inside; or again friction straps
differentially connected to the levers 10 may be applied to the wheel flanges 10 or
to separate pulleys fixed on the axle or axles.
Having thus particularly described my said Invention and the manner of per-
forming the same, I have to state that I do not restrict myself to the precise details
herein described or delineated; but that what I believe to be novel and original
and claim as secured to me by the herein-before in part recited Letters Patent is,
the arrangement of retarding and restarting apparatus for tramway and other
carriages wherein reversely acting grippers or their equivalents are applied directly
to wheels or axles of the carriage, and are connected to a spring or springs, the
reaction of which restarts the carriage, as required, on releasing the oppositely
acting gripping mechanism, substantially as herein-before described.
In witness whereof, I, the said Laurence Hill, have hereunto set my hand
and seal, this Eighth day of October, in the year of our Lord One thousand
eight hundred and seventy-seven.