IMPROVEMENTS IN MEANS FOR STARTING TRAM- CARS
Year: 1883

page_text: LETTERS PATENT to Benjamin Joseph Barnard Mills of the firm of Harris
and Mills of 23 Southampton Buildings in the County of Middlesex Patent
Agent for an Invention of IMPROVEMENTS IN MEANS FOR STARTING TRAM-
CARS communicated to him from abroad by Philip Brackley Shaw, Manufac-
turer, of the City of Williamsport, in the County of Lycoming and State of
Pennsylvania in the United States of America
PROVISIONAL SPECIFICATION left by the said Benjamin Joseph Barnard
Mills at the Office of the Commissioners of Patents on the 4th April 1883.
BENJAMIN JOSEPH BARNARD MILLS of the firm of Harris and Mills of
23 Southampton Buildings in the County of Middlesex Patent Agent IMPROVE-
MENTS IN MEANS FOR STARTING TRAM-CARS A communication to me from abroad
by Philip Brackley Shaw, Manufacturer, of the City of Williamsport, in the County
of Lycoming and State of Pennsylvania in the United States of America
The invention relates to starters for tram-cars, of that class which employ a
sliding draw-bar, and a clutching device connected therewith and working on the
car-axle, such clutching device being adapted to grip the axle on its forward
movement only.
The object of the invention is to produce a starter of this character, which will
be capable of long use and considerable wear without losing its efficiency or its
certainty of action; which will have a large bearing surface in the individual
gripping devices and will be provided with a plurality of such devices so as to
distribute the strain and prevent all liability to slip: which will be provided with
a suitable mechanism for throwing the gripping devices out of action and one not
affected by the settling of the car upon its springs, and with means for compelling
the driver to throw the gripping devices out of action at one end of a car before ho
can detach the horses or shift them to the other end of the car: and which will be
constructed for the ready removal and replacing of the gripping devices without
taking the oscillating collar apart or removing it from the sleeve that is secured to
the axle.

page_text: If the car is drawn from one end only one starter will be used, placed on the
axle next to the forward end of the car and connected with the draw-bar: but if
the car is designed to be drawn from either end, two starters will be employed,
(one on each axle) connected with the opposite draw-bars.
A description of one starter will be sufficient for an understanding of the
invention.
Upon the car axle is secured a divided sleeve. It has an enlarged contral portion
with which the gripping devices engage.
Upon this sleeve is placed loosely a collar also made in two parts, and enclosing
the central enlarged portion of the sleeve which turns within the collar when the
car is in motion.
Heretofore the central portion of the sleeve has been provided with a single
groove, in which worked a gripping ball carried by a cam-headed lever pivotted in
a slot in the collar, and another ball playing in a tapering groove in the collar and
serving to prevent any retrograde movement of the car. But these devices lost
their efficiency after a little wear, and the bearing surface of each ball being only
about one eighth of an inch, the strain was all at one point and increased largely
the danger of breaking the collar.
Instead of a concentric groove, there are employed in this starter two or more
cam-grooves. Each of these grooves preferably approximates in shape a part of a
true spiral, its radius decreasing regularly for every degree of revolution. The
shoulders where the points of greatest and least radii meet are given a rounded or
curved form.
The cam grooves, of which there may be two, three, four or more, are located
when there are four with their points at the quarters of a circle so that three of
them will always be in position for effective operation.
Rollers (one for each groove) bear on the cam faces of these grooves and play in
a chamber formed in one part of the surrounding collar. The bearing surface of
this enclosing chamber is eccentric with the axle, and the cam grooves divide this
chamber into a number of tapering parts, each part being smaller at the lower end
of such chamber than at its upper end.
This enclosing chamber has a number of extended openings closed by a removable
plate. Through these openings the rollers are put into or removed from the
chamber, and into these openings the rollers are pushed in succession by the points
of the cams.
When the point of any one cam passes the inner end of the opening in line with
it, the roller moves into the space made by the regularly receding face of the cam,
and travels towards the lower end of the enclosing chamber, turning in the opposite
direction to the sleeve until the point of the cam lifts the roller out of the chamber
and pushes it into one of the extended openings.
In the operation of starting the car, the collar is turned by the forward move-
ment of the draw-bar as will be well understood upon the sleeve, and the rollers
are jammed between the bearing surface of the enclosing chamber and the cam
grooves, locking the collar to the sleeve: the further movement of the collar turns
the sleeve and the car axle to which it is attached.
The enclosing chamber being less than a quarter of a circle in extent, three of
the rollers are always in position to act, and, at times, all four are in position to
grip the sleeeve,
The cam surfaces and rollers wear evenly and by such wear the point of effective
gripping on the cam is somewhat changed, but the efficiency of the starter is not
materially decreased.
When the extent of effective gripping surface is materially reduced by wear,
new and larger rollers can be readily inserted, and the starter will be as efficient
as when first put in operation.
The rollers prevent any retrograde movement of the car by a gripping action
which is caused by the reverse movement of the sleeve within the collar, instead
of by the forward movement of the collar, on the sleeve as is the case in starting.

page_text: The rollers which are used have many advantages over the balls almost
universally employed heretofore. They bear the whole width of their faces while
the balls bear at one point only. Consequently the rollers are much more certain
in their action. The rollers can also be made absolutely true at small expense and
will wear evenly while the balls cannot be constructed of true spherical shape and
in addition wear unevenly. The use of a number of gripping devices, distributes
the strain and lessens the liability of the breaking of any of the parts.
A projecting arm or lever is cast with one part of the collar, or is secured solidly
to one or both parts of such collar.
This lever is connected with a chain passing over a sheave secured to the bottom
of the car, and attached to a rod running to the spring retracted draw-bar.
The lever can be made solid with the collar, for the reason that the two operations
of the starter are performed by the rollers that lie between the collar and the cam
surfaces of the grooves.
To throw the rollers out of action, rods are used (one for each roller) which pass
through the bottom of the enclosing chamber.
These rods are connected by a bar, by raising which the rollers will be forced
into the extended openings and the sleeve will be free to turn backward in the
collar.
It is only necessary in this form of starter to raise the rollers, which weigh at
the most but a few ounces, while with that employing a gripping lever, the whole
collar has to be raised on its rear side in order to allow the lever to drow back out
of action.
The rock shaft which operates the throwing out rods is mounted directly upon
the collar being carried thereby.
This shaft has a horizontal arm connected with the bar which couples the
throwing out rod together, and a vertical arm connected with a rod extending
forward and connected with one arm of a bell-crank pivotted beneath the platform.
The other arm of this bell-crank is connected with a step projecting up through
the platform.
When the step is depressed the rollers are thrown out of action. By one form of
the device, the rollers are locked out of action by a bevelled catch on this step which
engages with a shoulder on the draw-bar.
The forward movement of the draw bar releases the step. By another form of the
device, the vertical arm of the rock-shaft on the collar is provided with a pivotted
locking arm or latch, which, when the throwing out rods are raised by the move-
ment of the step, drops over a shoulder or projection on the collar and locks the
devices out of action.
The step does not lock with the draw-bar, but is thrown upwardly by a weighted
arm when relieved from pressure. To release the throwing out devices, the
pivotted latch is thrown off the shoulder by a spring bell crank operated by rods
running to the platform, and arranged so that one arm will strike the latch and
raise it from the shoulder.
To prevent the driver from detaching the horses until the rollers are thrown out
of action, either of two devices may be employed.
The dash board may be provided with a bracket or arm covering the book of the
draw-bar, and the step be constructed with a bevelled face engaging a slot in the
draw-bar and forcing it forward. By this device the horses cannot be detached
until the draw-bar is thrown forward by depressing the step, which movement
throws the rollers out of action.
Or the step may be provided with an oblique slot engaging a pin on the sliding
bolt, and so arranged that the bolt will be projected over the point of the draw-bar
hook when the step is raised and withdrawn when the step is depressed.

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent filed by
the said Benjamin Joseph Barnard Mills in the Great Seal Patent Office on
the 3rd October 1883.
"
BENJAMIN JOSEPH BARNARD MILLS of the firm of Harris and Mills of
23 Southampton Buildings in the County of Middlesex Patent Agent "IMPROVE-
MENTS IN MEANS FOR STARTING TRAM-CARS A Communication to me from abroad
by Philip Brackley Shaw, Manufacturer, of the City of Williamsport in the County
of Lycoming and State of Pennsylvania in the United States of America
The Invention relates to starters for tram-cars, of that class which employ a
sliding draw bar, and a clutching device connected therewith and working on the
car-axle, such clutching device being adapted to grip the axle on its forward
movement only.
The object of the invention is to produce a starter of this character, which will
be capable of long use and considerable wear without losing its efficiency or its
certainty of action: which will have a large bearing surface in the individual
gripping devices and will be provided with a plurality of such devices so as to
distribute the strain and prevent all liability to slip: which will be provided with a
suitable mechanism for throwing the gripping devices out of action and one not
affected by the settling of the car upon its springs, and with means for compelling
the driver to throw the gripping devices out of action at one end of a car before he
can detach the horses or shift them to the other end of the car: and which will
be constructed for the ready removal and replacing of the gripping devices without
taking the oscillating collar apart or removing it from the sleeve that is secured to
the axle.
If the car is drawn from one end only, one starter will be used, placed on the
axle next to the forward end of the car and connected with the draw bar; but if
the car is designed to be drawn from either end, two starters will be employed (one
on each axle) connected with the opposite draw-bars.
And in order that the said Invention may be more clearly understood and readily
carried into effect I will proceed aided by the accompanying Drawings more fully to

page_text: Herefore the central portion of the sleeve has been provided with a single groove in
which worked a gripping ball carried by a cam lever pivotted in a slot in the collar and
another ball playing in a tapering groove in the collar and serving to prevent any
retrograde movement of the car, but these devices lost their efficiency after a little
wear, and the bearing surface of each ball being only about one-eighth of an inch,
the strain was all at one point and increased largely the danger of breaking the
collar. Instead of a concentric groove there are employed in this starter two or
more cam grooves CDE F. Each of these grooves preferably approximates in
shape to a part of a true spiral, its radius decreasing regularly for every degree of
revolution. The shoulders c, d, e, f, where the points of greatest and least radius
meet are given a rounded or curved form. The cam grooves, which are shown as
four in number, are located with their points at the quarters of a circle so that
three of them will always be in position for effective operation. Rollers G, H, I, K.,
bear on the cam faces of these grooves and play in a chamber L formed in one part
of the collar B. The bearing surface g of this chamber is eccentric with the axle,
and the cam grooves divide this chamber into a number of tapering parts, each part
being smaller at the lower end of such chamber than at its upper end.
The chamber L has a number of extended openings h closed by a removable
plate i. Through these openings the rollers are put into or removed from the
chamber L, and into these openings the rollers are pushed in succession by the
points of the cama. When the point of any one cam passes the inner end of the
opening in line with it, the roller moves into the space made by the regularly
receding face of the can, and travels towards the lower end of the chamber L,
turning in the opposite direction to the sleeve until the point of the cam lifts the
roller out of the chamber L and pushes it into one of the openings h.
In the operation of starting the car, the collar B is turned, as will be well
understood upon the sleeve and the rollers are jammed between the surface g of
chamber L and the cain grooves, locking the collar to the sleeve; the further
movement of the collar turns the sleeve and the car axle to which it is attached.
The chamber L being less than a quarter of a circle in extent three of the rollers
are always in position to act and at times, all four are in position to grip the sleeve.
The cam surfaces and rollers wear evenly, and by such wear the point of effective
gripping on the cam is somewhat changed, but the efficiency of the starter is not
materially decreased. When the extent of effective gripping surface is reduced
materially by wear, new and larger rollers can be readily inserted and the starter
will be as efficient as when first put in operation. The rollers prevent any
retrograde movement of the car by a gripping action which is caused by the
revorse movement of the sleeve within the collar, instead of by the forward
movement of the collar on the sleeve as is the case in starting.
The rollers which are used have many advantages over the balls heretofore
employed. They bear the whole width of their faces while the balls bear at one
point only. Consequently the rollers are much more certain in their action. The
rollers can also be made absolutely true at small expense and will wear evenly
while the balls cannot be constructed of true spherical shape and in addition wear
unevenly. The use of a number of gripping devices, it will be seen, distributes
the strain and lessens the liability of the breaking of any of the parts.
M is a lover, which is cast with one part of the collar B, or is secured solidly to
one or both parts of such collar. This lover is connected with a chain, passing over
a sheave secured to the bottom of the car and attached to a rod running to the
spring retracted draw bar N.
The lever M can be made solid with the collar, for the reason that the two
operations of the starter are performed by the rollers that lie between the collar
and the cam surfaces of the grooves. This lever may be pivotted to the collar
and may carry a roller bearing on the central contentric surface k, and it may be
limited in its movement or adjustably fixed by means of set screws. The office of
the roller carried by it however will only be to take most of the strain off of the
gripping rollers when the car is in motion.

page_text: To throw the rollers out of action rods O are used (one for each roller) which
pass through the bottom of the chamber L. These rods are connected by a bar /
by raising which the rollers will be forced into the openings h and the sleeve will
be free to turn backward in the collar. It is only necessary to raise the rollers in
this form of starter (which weigh at the most but a few ounces) while with that
employing the gripping lever the whole collar has to be raised on its rear side in
order to allow the lever to drop back out of action.
To prevent the settling of the car on its springs from affecting the throwing out
device, the rock shaft m which operates the rods O is carried directly by the
collar.
In the form shown in Figures 1, 2, and 3, it has an arm n connected by a chain
with the bar of the lifting rods O and another arm p connected by a slotted rod g
with an arm secured to a rock shaft turning in a bracket from the casing in
which the draw bar slides. The other arms of this last rock-shaft is connected
with a step or other suitable device t. This step plays through a slot u in the
draw bar N and has a bevilled shoulder y which when the step is forced down-
wardly to throw the starter out of action pushes the draw-bar forward and locks
it in that position.
A bracket Q is secured to the dash-board of the car and projects over the point
of the book w of the draw-bar when such draw bar is retracted. This bracket Q
prevents the driver from detaching his horses until the draw-bar is forced forward
by the depression of the step t which throws the starter out of action. Hence in
shifting the horses from one end of the car to the other, the driver is obliged to
set the starters properly. As soon as the horses commence to pull upon the draw
bar the starter at that end of the car is put in action.
In Figure 5, which illustrates a different method of locking the gripping devices
and preventing the detaching of the horses before such locking is accomplished.
Dis the collar surrounding the enlarged portion C of the sleeve on the axle
and c is the chamber within said collar.
One of the gripping devices is shown in this figure in dotted lines at a.
A rigid lever E is attached to collar D from which lever extends a chain F
passing over a sheave attached to the bottom of the car at G, and being attached
to the draw-bar H, which is provided with a spring enclosed by the box b and
which terminates in a hook I at the end of the car, to which hook the horses are
to be attached.
When the mechanism is in operative position, the gripping devices a are in
contact with the sleeve C.
The pulling of the horses on the draw-bar turns the collar D upon the sleeve C
and causes the devices a to grip said sleeve and assist in turning the axle, and
when the car stops and the traces slacken the collar D falls back and is ready for
operation when the car starts again as previously explained.
A. spring J is shown in this figure which may be provided to assist in bringing
the collar back into position, it being desired to do this very quickly.
Rods & are employed to throw the rollers a out of position.
The rods & are moved by arms fg and h, the rod h being attached to a rock
shaft i mounted on the collar D. An arm j from the rock shaft i extends to pin
and from pin the rod K having a slot k¹ runs to the end of the car where it is
attached to arm of rock shaft m.
The arm n of said rock-shaft is attached to the lower end of the step L.
Thus the pressing down of the step L causes the movement of the rod K, and
through the intermediate arms, the gripping devices a, are thrown up out of
contact with the sleeve C. A weighted arm m' attached to shaft m turns said
shaft to throw the step up again, the slot kl. allowing this to be done without
interference with the throwing out and locking devices.
With this form of the invention, an additional locking device is provided to bold
the gripping devices. out of position independent of the vertical movement of the

page_text: This consists of the arm o which is attached to arm j, and is provided with a
catch p, which when the arms j and o are pushed forward by the throwing back
of the rod K, engages with a projection q on the collar D, and thus holds the
armj back and keeps the rods d pressed up and holding the gripping devices a.
This locking armo being pivotted to a part mounted upon the collar of the
starter and also locking with a projection from such collar, the gripping devices
will be held by it out of operative position independent of the vertical movement
of the car on its springs.
To release the catch p a rod L' terminating in a ring handle is placed in a
convenient position at the end of the car and is connected with arms r, 8, of a
bell-crank sleeved on the rock-shaft m.
From arm & runs a rod M attached at its other end to the arms t, u, of
a bell-crank. When rod L¹ is pulled up arm t strikes the end of rod o and
raises the catch p, thus allowing the gripping devices to fall again into operative
position.
A spring is attached to rod M to return it, and the parts attached to it to their
former positions.
Passing through the step L is a bolt N, (Figures 5 and 6) having a pin w which
enters a curved slot x in the step. The bolt normally covers the draw-bar hook I
as shown, so that the horses cannot be detached from the car until the step is
pressed down, when the pin in the slot causes the drawing back of the bolt and
uncovers the hook.
When the direction of the car is to be reversed the driver pushes down the
step I, and thus throws out the gripping devices and locks them.
He is then able to unhook the horses from the draw-bar. Before starting he
raises the rod L' at the then forward end of the car and thus throws the starter
at that end into action.
Having thus described the nature of the said Invention and the mode in
which the same is carried into effect I would have it understood that what I
claim is:
First. In car starters, the combination of a sleeve mounted on the axle, a
loose collar on said sleeve, and two or more gripping devices intermediate between
said collar and sleeve and working on cam surfaces, substantially as herein
described.
Second. Means unaffected by the vertical movement of the car body for locking
the gripping devices of the car starter out of operativo position, substantially as
herein described.
Third. Means for preventing the detaching of the horses until the car starter
is thrown out of action, substantially as herein described.
In witness whereof I the said Benjamin Joseph Barnard Mills have hereunto
set my hand and seal this third day of October in the year of our Lord One
thousand eight hundred and eighty three.
SETETA