IMPROVEMENTS IN APPARATUS FOR PROPELLING AND RETARDING TRAMWAY CARS
Year: 1877

page_text: LETTERS PATENT to William Clark, of 53, Chancery Lane, in the County of
Middlesex,, Patent Agent, for the Invention of "IMPROVEMENTS IN APPARATUS
FOR PROPELLING AND RETARDING TRAMWAY CARS." A communication from
abroad by John Bleeker Tibbitts, of Hoosick, County of Rensselaer, State of
New York, United States of America.
Sealed the 22nd January 1878, and dated the 28th August 1877.
PROVISIONAL SPECIFICATION left by the said William Clark at the Office
of the Commissioners of l'atents on the 28th August 1877.
"
WILLIAM CLARK, of 58, Chancery Lane, in the County of Middlesex, Patent
Agent. IMPROVEMENTS IN APPARATUS FOR PROPELLING AND RETARDING
TRAMWAY CARS." [A communication from abroad by John Bleeker Tibbitts, of
Hoosick, County of "Rensselaer, State of New York, United States of America.]
This Invention relates to apparatus for propelling tramway cars by means of
steam engines or other similar motors, and it consists of a frame suspended centrally
from the car frame, and carrying two shafts, upon which friction wheels are secured.
The supports for the said shafts are capable of both vertical and lateral motion.
The Invention further consists in the arrangement of two wheels revolving on
inclined axes in contact with the rail and with the friction wheels before
mentioned.
The principal object of the Invention is to concentrate as much as possible of the
weight of the load at one point, that is, at the point at which the driving power is
applied at the moment of starting, and thereafter as the car progresses to a greater
or less degree, according to the resistance of the gradient and varying weight of the
load.
The propelling apparatus is supported upon a cross timber attached to the frame
of the car, and provided with the vertical dovetail ways to which slides are fitted,
which are also provided with transverse dovetail ways, and upon these are placed
D
017

page_text: supports for vertical shafts. The transverse ways are chambered out to receive a
spring made of india-rubber, steel, or other suitable material. The ends of the
spring rest against lugs formed on the back of the supports of the vertical shafts,
and tend to force the said supports apart.
Small friction wheels are secured to the vertical shafts upon which bear inclined
wheels having right angled grooves lined with india-rubber or other elastic material
fitted to the elevated portion of the rail and to the friction wheels.
The inclined wheels are also provided with a bevelled surface which runs in con-
tact with or near the lower portion of the rail.
The axles of these inclined wheels run in boxes that are pivoted between arms
rigidly secured together by a cross bar, and pivoted to studs that project down-
ward from the frame of the car.
It will be seen that the downward pressure of the vertical shafts tends to thrust
the inclined wheels against the rails diagonally with considerable force. The in-
crease of downward and lateral force increases the bite of the inclined wheels upon
the rails, and also increases the friction between them and the friction wheels.
Any convenient power may be employed to drive the vertical shafts, and they
may be forced apart laterally by means of a spring, as described, or by a suitable
arrangement of air-pressure cylinders.
In some cases the vertical shafts will be omitted, and the power will be applied
directly to the inclined wheels either by a connecting rod connected with a suitable
engine, or by means of wire ropes running around sheaves attached to the said
wheels.
By reversing the action of the wheels and proportioning the thrust to the load,
the propelling apparatus becomes an effective means of retarding the car.

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent filed
by the said William Clark in the Great Seal Patent Office on the 22nd January
1878.
WILLIAM CLARK, of 53, Chancery Lane, in the County of Middlesex, Patent
Agent. "IMPROVEMENTS IN APPARATUS FOR PROPELLING AND RETARDING
TRAMWAY CARS." A communication from abroad by John Bleeker Tibbitts, of
Hoosick, County of Rensselaer, State of New York, United States of America.
This Invention relates to apparatus for propelling tramway cars by means of
steam engines or other similar motors, and it consists of a frame suspended centrally
from the car frame, and carrying two shafts, upon which friction wheels are secured.
The supports for the said shafts are capable of both vertical and lateral motion.
The Invention further consists in the arrangement of two wheels revolving on
inclined axes in contact with the rail and with the friction wheels before
mentioned. The axles of the said wheels are journalled in pivoted boxes that are
supported by swinging arms pivoted to a stud that projects downward from the
car frame.
The principal object of this Invention is to concentrate as much as possible of the
weight of the load at one point, that is, at the point at which the driving power is
applied at the moment of starting, and thereafter as the car progresses to a greater
or less degree, according to the resistance of the gradient and varying weight of the
load.
Figure 1 of the accompanying Drawings is a longitudinal vertical section on
line y, y, Figure 2; and Figure 2 is a transverse section on line x, x, Figure 1, of
the car frame provided with the apparatus of this Invention.
Similar letters of reference indicate corresponding parts in the two Figures.
In the Drawing A is a cross timber attached to the frame of the car for support-
ing the vertical dovetail ways B, B. To these ways the slides C are fitted, which
are also provided with transverse dovetail ways D, upon which are placed the sup-
ports E for the vertical shafts F. The ways D are chambered out to receive a
spring G, which, as shown in the Drawings, would be made of india-rubber, but it
may be of steel or other suitable material. The ends of the spring G rest against
lugs formed on the back of the supports E, and tend to force the said supports
apart. H, H, are wheels secured to the vertical shafts F; and I, I, are wheels
having right-angled grooves a, which are lined with india-rubber or other clastic
material, and run on the elevated portion of the rail, and in contact with the fric-
tion wheels H. The wheels I are bevelled at b, to run in contact with or near the
lower portion of the rail. J, J, are the axles of the wheels I, which run in boxes K
that are pivoted between the arms L, which are rigidly secured together by a cross
bar c.
The arms L are pivoted to the studs M that project downward from the
frame of the car.
It will be seen that the downward pressure of the shafts F tends to thrust
the inclined wheels against the rails diagonally with considerable force. The
increase of downward and lateral force increases the bite of the wheels I upon the
rails, and also increases the friction between the wheels H, I.
Any convenient power may be employed to drive the shafts F, and they may
be forced apart laterally by means of a spring, as described, or by a suitable
arrangement of air-pressure cylinders.
In some cases the shafts F will be omitted, and the power will be applied directly
to the wheels I, either by a connecting rod connected with a suitable engine, or by
means of wire ropes running around sheaves attached to the said wheels 1.
By reversing the action of the wheels, and proportioning the thrust to the
load, the propelling apparatus becomes an effective means of retarding the car.
Having described the nature of the said Invention, and the manner of performing
the same, I declare that what I claim as the Invention to be protected by the
herein-before in part recited Letters Patent is,―
1st. The driving wheels suspended in an inclined plane, and capable of acting

page_text: separately and independently of the momentum of the car for propelling or
retarding the car, substantially as herein set forth.
2nd. The inclined wheels I supported by arms L, and driven by friction
wheels H, substantially as shown and described.
3rd. The combination of the ways B, slides C, ways D, supports E, spring G,
and shafts F, substantially as shown and described.
4th. The combination of the inclined wheels I, having axles J, the pivoted
boxes K, and arms L, substantially as shown and described.
5th. The inclined wheels 1 when acted upon directly by the motive power
that drives the car, substantially as specified.
6th. The wheels I placed on inclined axles, and employed in retarding the car
as specified.
In witness whereof, T. the said William Clark, have hereunto set my hand
and seal, this Twenty-second day of February, in the year of our Lord One
thousand eight hundred and seventy-eight.
WM. CLARK.
(LL.M.)