Improvements in Stopping and Starting Appliances for Tramcars and other similar Vehicles.
Year: 1893

page_text: Date of Application, 29th Aug., 1893
Complete Specification Left, 11th Dec., 1893-Accepted, 13th Jan., 1894
PROVISIONAL SPECIFICATION.
Improvements in Stopping and Starting Appliances for Tramcars
and other similar Vehicles.
I EDMUND CHADWICK of 1, Falcon Street Douglas Isle of Man Retired
Builder do hereby declare the nature of this invention to be as follows :-
I place near the centre of each axle and fast on the same a toothed wheel with
another toothed wheel close to it but arranged in such a way by means of a pawl
and rack wheel that when the axle is turning one way it is perfectly loose and free,
but turning the opposite will grip the said axle and only turn with it. Parallel
with the said axle, and at a suitable distance apart and supported by it in a small
frame I place a short shaft having on it two toothed wheels, one of which can be
thrown in and out of gear with the fast wheel on shaft by means of a sliding wedge
and rod to be actuated from front of car. Above and geared into the fast wheel
on short shaft and gearing into loose wheel on axle when thrown into action 1 place
a toothed bar, sliding in grooves, of a suitable length to extend some distance
beyond each wheel. At one end of this toothed bar I place a round disc or plate
fitted to slide easily in a tube or cage supported between the axles on frames in
such a position that its centre is near the centre of the toothed bar.
Inside this tube or cage and between the two plates I place a coil or spiral
spring of a suitable length and strength according to the power required.
The said wheels being put into gear would act as a break while compressing the
spring and being released the spring acting on the toothed bar then geared into the
loose wheel on axle would assist in again restarting vehicle.
Dated this the 29th day of August 1893.
EDMUND CHADWICK.
Improvements in Stopping and Starting Appliances for Tramcars
and other similar Vehicles.
EDMUND CHADWICK 1, Falcon Street Douglas Isle of Man Retired Builder
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:-
To render my invention perfectly clear I will now proceed to describe the same
by aid of the four sheets of drawings forming part of this Specification.
Before however I proceed to describe my invention I wish it to be distinctly
understood that I do not confine myself to the exact details shown.
Referring to Sheet (1) of drawings, Fig. 1, shows a longitudinal elevation of
frame and wheels of a tram car showing my invention applied. Fig. 2, shows a plan
of Fig. 1.
Referring to Sheet, 2, Fig. 3, shows an enlarged detail in plan of one end of my
apparatus. Fig. 4, shows an enlarged sectional elevation of one end of the
apparatus. Fig. 5, shows an end view of Fig. 4, Fig. 6, is a detail of the rack bar
and pawl.
Fig. 7, Sheet 1. shows my arrangement adapted sɔ as to fasten to one axle
only

page_text: Referring to Sheet 3, Fig. 8, shows the method of arranging chain wheels, pawl
wheels and pawl.
Fig. 9, shows a side view of pawl wheel.
Figs. 10 and 11. shows both sides of short chain wheel.
Fig. 12. is a section of Figs. 10 and 11. showing position of pawls. Fig. 13. shows
side view of long chain wheel.
Referring to Sheet 4 Fig. 14. shows a general plan of my arrangement as shown
on Sheet 3.
I will now proceed to describe in detail the various parts of my invention. The
apparatus consists of a toothed wheel, a, fastened on to each axle, and with a loose
toothed wheel, b, close to it, flanged on one side to carry a pawl d which is so
geared into another toothed wheel, c, (which is fast on the axle) so as to run quite
free and loose when turning in one direction. Parallel with the said axle and at a
suitable distance apart and supported by it by means of a small frame, e, I place a
small shaft, f, having on it two toothed wheels, g and h, one of which lettered, g,
can be thrown in and out of gear with the fixed wheel, a, on axle, by means of a
sliding wedge plate, i, which being connected by a rod, j, shown in Fig. 2. to rack
bar, k, at end of car can be easily applied by the person in charge. Between
the two frames, e e, I place a tube or cage, l, containing a spiral coil spring, m, of
a suitable length and strength according to the amount of power required, at each
end of spring I place a round disc, n, fitted to slide easily in tube, 1, I also place a
rack bar, o, as shown in detail in Fig. 6. above and gearing into wheels, h, and b,
and extending from disc, n, to a sufficient distance beyond toothed wheel, h, to
allow it to be moved a sufficient distance to allow it to conipress the spiral spring, m,
I also tooth the rack bar on one side as shown in drawings and in such a manner as
to gear with a pawl, p, which is pivoted on the upper side of frame and which is
kept in contact with the rack bar by means of a small spring, q, as shown, but
which is thrown and kept out of gear when the wedge plate, i, is fully drawn out,
which has the effect of drawing over a slotted plate, r, sliding against end of
frame, e. The action of this arrangement of parts would be that supposing the
car to be moving and the person in charge wishing to stop it, by turning the
lever, s, shown on Fig. 1 Sheet 1 the rack bar, k, forcing the wedge plate inwards
the toothed wheel, g, would be thrown into gear with the toothed wheel, a, causing
the toothed wheel, h, to force the rack bar, o, in the direction of the cage thus
compressing the spiral spring, m. On the action being reversed and the wheels
thrown out of gear the whole pressure of the spiral spring being directed on to
the toothed wheel, b, by means of the rack bar, o, assists to start the car. If it
should not be necessary to utilize the power of the spring in restarting as would
be the case going down hill by moving lever only half way back the wedge
plate being thus only partly drawn out the toothed wheels, g and a, would be
thrown out of gear without releasing the coil spring which would leave the car
free to travel on. The power of spring being then stored could be utilized when
required.
In cases where it was not convenient to have the cage connected to both axles,
as in the case of vehicles with bogie wheels, one end of the cage could be supported
loosely from the underside of frame of car in such a manner as to allow it to move
sideways with the action of the bogie as shown in Fig. 7. Sheet 1. The small
shaft,, with its accompanying wheels is shown on the drawings on the opposite
side of axle to the spiral spring, m, but when it was necessary this could be placed
between spring and axle. If more power was required the two axles could be
connected by an endless chain working on toothed wheels fixed on the axles as
shown in Fig. 2, Sheet 1.
Another method of applying this invention would be to place two chain
wheels, T and v, in the position shown in Fig. 8, Sheet 3, of drawings, on a tube,
fitting quite loose round the axle, except when applied, but which tube is attached
at one end to one of the toothed wheels, as shown in Fig. 12 Sheet 3, though I
prefer to attach it to toothed wheel v Fig. 13, and placing an endless chain passing

page_text: through the centre of spiral spring, m, and disc, n, Sheet 2, and round chain
wheels, t, and geared into them as shown. On that side of disc nearest the chain
wheel, r, I place a pin projecting through the chain on each of a suitable length
so that when the chain is moved in either direction it will carry the disc, n, with it
compressing the spring, m. On that side of the chain wheel, v, nearest to chain
wheel, T, I cut two grooves of a suitable length and in the position shown in.
Fig. 13, and of a suitable depth to correspond with the depth of the teeth on pawl
wheel, S. At one end of each groove and in the thickness of the wheel I place
a loose stude with a shaped end as shown and which is caused to project out
beyond the groove to the face of the wheel by means of a spiral or other spring
of a suitable strength that when the stud is brought in contact with the pawls, w,
it will force them into gear with the pawl wheel, S, I also place an endless chain
round chain wheel, T, and round small wheel, h, on short shaft in the position
shown in Fig. 8. Through the thickness of the chain wheel, T, and in the
position shown in Fig. 12. I place two pawls, w w, which are kept out of gear
with the pawl wheel, S, when not applied by means of spiral or other suitable
springs. On the side of chain wheel, T, I place pawl wheel, S, which is fast on
the axle. On that side of pawl wheel, S, nearest to chain wheel, T, I cut two.
circles of teeth in opposite ways one inside the other as shown in Fig. 9. I also
arrange the wedge plates, ii, in the position shown in Fig. 14. that being connected
by the rod, z, both are thrown in and out. of gear together. The action of this
arrangement of parts would be that the toothed wheel, g, being thrown into gear-
with the toothed wheel, a, the chain wheel, T, forcing the pawl, w, against the
stud, x, would cause it to gear with the pawl wheel, S, the other pawl having
moved to the opposite end of slot or groove would carry chain wheel, v, round
with it and thus compress the spring, m. On the toothed wheels, g and a, being
again thrown out of gear the chain wheel, T, being now geared into the pawl
wheel on the axle would be carried round by the chain wheel, v, until the power
of the spring, m, was exhausted the pressure then being taken off the pawls they
would release themselves leaving the axle free.
Having now particularly described and ascertained the nature of my inven-
tion and in what manner the same is to be performed I declare that what I
claim is:
1st. The general arrangement, construction and combination of parts comprising
the improved apparatus for stopping and restarting tram cars and other vehicles
substantially as herein before described and shown.
2nd. An apparatus for improving the stopping and restarting tram cars and
other vehicles by placing a spiral spring in a suitable position for the rack bar
actuated by the wheels or the endless chain passing round the wheels to operate on
substantially as herein before described and shown.
3rd. The general arrangement of the short shaft and the means by which the
spring being compressed in stopping has its full force directed to again assist in
restarting the car on being released substantially as herein before described and
shown.
4th. The arrangement of the toothed wheels, racks, endless chains pawls, and the
ways of gearing the same together when required and also the sliding plate for
applying the same substantially as herein before described and shown.
5th. The arrangement of pawl working into side of rack bar and means for
throwing it in and out of gear when required thus allowing the acquired force to be
stored substantially as herein before described and shown.
Dated this the Sixth day of December One thousand eight hundred and ninety-.
EDMUND CHADWICK.