Improvements in Brakes for Tram Cars and the like Vehicles.
Year: 1892

page_text: Date of Application, 15th Oct., 1892
Complete Specification Left, 15th July, 1893-Accepted, 14th Oct., 1893
PROVISIONAL SPECIFICATION.
Improvements in Brakes for Tram Cars and the like Vehicles.
I, WILLIAM WESTMORELAND, of 1, Lynn Street, West Hartlepool, in the
County of Durham, Watchmaker, do hereby declare the nature of this invention
to be as follows :-
My invention relates to the brakes of tram cars or the like heavy vehicles, the
axles of which rotate with the wheels.
Brakes as ordinarily constructed for tram cars effect their purpose by the
application of friction to the wheels of the car until the momentum of the car is
overcome. The car has then to be restarted by the extra effort of the horses or
engine as the case may be.
The object of my invention is to store up the power developed in overcoming
the momentum of the car in order to bring it to a standstill by means which will
again give out the power so stored up as an aid to the effort required to restart
the car.
My invention consists as follows:-A spur wheel is loosely mounted on each axle
so that the two spur wheels are in line with each other and geared together by a
rack. This rack passes through a spiral spring enclosed in a tube and is
furnished with pins or their equivalents projecting from the rack sides so as to
spur wheels
engage with and compress the spiral spring when the rotation of the
or either of them imparts a lateral motion to the rack. The spur wheels are only
brought into action for this purpose and otherwise remain stationary upon the axles
whether the car is in motion or at rest.
wheels
In order to bring the said spur
into action in the manner required for the purpose of my invention, I gear one spur
wheel into a clutch controlled by a lever, and furnish the other spur wheel with a
grooved wheel controlled by double-acting and self-locking detent clips or wedges.
When the clutch lever is operated to apply the brake and the clutch geared into
the clutch spur wheel the rack advances with a lateral motion and applies
compression to the spiral spring until the car is brought to a standstill.
tendency of the rack to recede in the opposite direction and so relieve the spiral
spring is prevented by the action of the detent clip or wedge which prevents the
spur wheel on the other axle from running back, as soon as the clutch spur wheel
is disengaged from its clutch the energy or stored up force represented by the
resilience of the compressed spring is brought into action through the rack and the
other spur wheel in the direction required to restart the tram car.
The
It will be readily understood that the above described brake mechanism can be
applied to vehicles generally in which the wheels are secured to their axles so that
the axles rotate with them.
I would also observe that the above described brake mechanism is not to be
considered as essential to my invention so far as relates to its details of construction
as any suitable brake mechanism may be employed by which the spur wheels and
rack are brought into combined action with the wheels of the car or other vehicle
for stopping and starting the same in the manner required as hereinbefore described
as constituting my invention.
Dated this 14th day of October 1902.
G. J. CLARKSON,
Stockton-on-Tees, Agent for the Applicant.

page_text: °
COMPLETE SPECIFICATION.
Improvements in Brakes for Tram Cars and the like Vehicles.
I, WILLIAM WESTMORELAND, of 1, Lynn Street, West Hartlepool, in the
County of Durham, Watchinaker, do hereby declare the nature of this invention
and in what manner the same is to be performed, to be particularly described
and ascertained in and by the following statement :-
My invention relates to the brakes of tramcars or the like heavy vehicles the
axles of which rotate with the wheels.
Brakes as ordinarily constructed for tramcars effect their purpose by the
application of friction to the wheels of the car until the momentum of the car and
its load is overcome. The energy so absorbed is not available as a stored up force
to be used for restarting the car which has to be done by an extra effort of the
horses or engine as the case may be and it is found that a constant recurrence of
the extra effort required to start a tram car which can be drawn along with ease
when once in full motion is especially injurious to horses.
The object of my invention is to overcome this difficulty by storing up the
power absorbed in overcoming the momentum of the car in order to bring it to a
standstill by simple and effective means which will again give out and utilize the
power so stored up with sufficient effect to in some cases partially and in other cases
fully restore to the car the speed at which it was going when pulled up by
the brake.
The means employed to effect the purpose of my invention consist mainly in a
combination of parts by which the motion of the wheels on which the car runs is
transmitted at will to a spiral spring the compression of which brings the car to a
standstill, provision being made by which the spring can re-expand itself in the
manner required for restarting the car.
Having so far described the nature of my invention and its utility I will now
proceed to describe in what manner it is to be carried into effect and for that
purpose shall refer to the accompanying drawings which illustrate my improved
brake fixed in position to the underframe of a tramcar.
In the drawings Figure 1 is a longitudinal sectional view of the brake apparatus
and underframe taken on line X X in Figure 2 which is a corresponding view in
plan.
In the drawing A is the underframe of a tram car which is to be taken as
representative of such underframes generally. This underframe A is mounted on
axles B B2 which rotate with the wheels CC. In these respects the tram car is
of the ordinary construction, the precise form indicated in the drawing being
given by way of illustration only.
The brake apparatus constituting my invention consists as follows:-A spur
wheel is loosely mounted on each axle so that the two spur wheels D¹ D² are in
line with each other and are geared together by a rack E. This rack passes
through a spiral spring F enclosed within a tube G which is fixed in position by
suitable attachments to the axles B' B². This tube is closed in at either end by
cover plates slotted across the centre for the rack to pass through the said cover
plates being intended to take the strain of the spring F when brought into
compression when the brake is applied. The rack E being thus enclosed within
the spiral spring F and tube G is so confined in its position and motion as to be
kept in constant gear with the spur wheels D' D2 in the manner required for the
purposes of my invention. The rack E is furnished with cross bars H or some
equivalent projections provided in the positions shown so that as the rack is thrust
inwards from either end a cross bar or the like projection comes into contact with
the end of the spiral spring which is compressed more or less according to the

page_text: extent of the movement imparted to the rack. The spur wheels are brought into
action with the compression and expansion of the spiral spring only and otherwise
remain stationary upon their respective axles whether the car is in motion or at
rest. I is a clutch mounted on the shaft B' and controlled by a lever J by which
it is put in or out of gear with the spur wheel D' at the option of the tramcar
driver or guard. K is a grooved or clip wheel controlled by the double acting
or reversible and self locking detent clip or wedge K' which is kept to its work by
the action of the spring L.
The several parts being arranged and combined as hereinbefore described and
shown in the drawing, they are intended to operate as follows:-
Taking the car as moving in the direction indicated by the arrow and the lever
pulled in the direction to stop the car the clutch I engages with the spur wheel D¹
and causes it to rotate with the axle B' on which it is mounted. This imparts a
lateral and upward motion to the rack E which accordingly compresses the spiral
spring F, from its lower end the combined strength and resilience of which is
designed to take up and give out the energy exerted in compressing it sufficiently
to stop the car. In order to utilize the power or energy so stored up in the
spirral spring it is essential that the said spring shall relieve itself only by the
propulsion of the car and in the same direction as it was going before. In order to
effect this there must be no retrograde movement of the spur wheel D² the rotary
motion of which has been following the lateral or upward travel of the rack.
Such retrograde motion is prevented by the detent clip K' controlled by the
setting spring L or by some other equivalent device.
It must also be understood that there must be no tendency of the rack E to
move in the direction of starting the car by chance or accident. This is provided
for by the relative size of diameter in the spur wheels D¹ D³ it being obvious that
with the car wheels CC2 of equal diameter which is usually the case, the rack E
geared to different sized wheels on the axles B1 B2 cannot move the car until one
of the spur wheels is free on its axle. Consequently by properly adjusting the
relative sizes of the spur wheels D¹ D' the clutch I and lever J can be used as
well for restarting the car as for stopping it and it is found that by having the
clutch spur wheel D' considerably smaller in diameter than the spur wheel D' on
the other axle that the spring F is not too suddenly compressed when the brake is
put on; and inasmuch as the restarting of the car is due to the rotary motion of
the spur wheel D² only, a larger diameter in this wheel becomes a mechanical
advantage in the leverage and movement of the rack E. Subject to the above
considerations the relative sizes of the said spur wheels is not a matter of careful
adjustment.
In order to reverse the action of the brake to enable the car to run in the
opposite direction the rotary motion of the wheel D² must be reversed, that is, the
detent clip K and its spring L are reversed as shown by dotted lines in Figure_1
which corresponds with the reversed movement of the spur wheel D¹ and rack E,
which are of course changed with the changed direction of the travel of the car.
The relative movements of the several parts as the brake begins to act are indicated
by arrows in Figure 1 all of which would be reversed together when the car is
reversed.
.
It must be understood that the above described brake mechanism will act the
same whether the car be wholly stopped or only merely retarded so long as the
stoppage or retardation is due to the action of the brake and not to independent
circumstances, such as inclines, changes of level or the conditions of the road.
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 :-
In the construction of brakes for tramcars and the like vehicles a combination of
parts by which the energy absorbed in overcoming the momentum of the tramcar
when required to stop it is stored up in the brake and given out again for restarting

page_text: the car, all arranged and operating together substantially as herein before described
with reference to the accompanying drawing.
Dated the 14th day of July 1893
G. J. CLARKSON,
Chartered Patent Agent,
Stockton-on-Tees, Agent for the Applicant.