IMPROVE- MENTS IN BRAKES
Year: 1880

page_text: PROVISIONAL SPECIFICATION left by Thomas Coltman at the Office of the
Commissioners of Patents on the 6th November 1880.
THOMAS COLTMAN, of Leicester, in the County of Leicester, Machinist. "IMPROVE-
MENTS IN BRAKES."
The object of my Invention is to arrange a brake apparatus that can be applied
to existing carriages and the other rolling stock, such as are used on railways, and
in such a manner that the brake will act automatically upon the wheels of every
vehicle to which the apparatus is applied when the speed of the motive power at
the head of the train is suddenly checked. To so construct the parts of the brake
apparatus, that although the wheels are locked from travelling forward, they are
free to run backward in the opposite direction to which they were travelling
when the brake was applied, and when power is again applied, the brake is
automatically removed from the wheels. Also to arrange the brake so that the
same can be reverse and applied to the wheels when vehicles are to run the opposite
way.
I accomplish my object somewhat in the following manner, and in explaining the
same will describe the apparatus as applied to one vehicle.
To the end of each draw bar I secure a stop bracket, to each of which are
attached chains or rods, connecting the same to one pair of brakes, so constructed
that when they are applied effectually lock the wheels and slide upon the rails.
In connection with each of these draw bars or brackets is an eccentric, tappet, or
other equivalent, which is also in connection with the guard's van, and is for the
purpose of arranging the brakes to act upon the wheels according to the direction
in which the vehicle is to run. When this eccentric, tappet, or other equivalent
has been adjusted, so that the draw bar at the leading end of the vehicle is free to
act, the latter bar is locked, and the brakes in connection therewith inoperative.
On the train being drawn along, the leading draw bar raises the brakes connected
therewith from off the wheels, but as soon as the engine drawing the same is
slackened, the momentum of the train presses the buffers together, relieving the
tension of the said draw bar, by which means the brakes descend until the soles of
the same rest upon the rails; the wheels then slightly mount upon the sole of the
brakes and are thereby locked, assisting to bring the train to a stand.
On reversing the motion of the train, the wheels thus locked return on to the rails
thereby freeing the wheels from the brakes, leaving the vehicle at liberty to travel
in a backward direction.

page_text: In order that both brakes in connection with each pair of wheels may act
together and travel quickly to and from the wheels, I connect each pair of brakes
together by suitable stays, and provide each brake with a projecting arm extending
to the axle box, in close proximity to which is secured an eccentric forming the
axis upon which the brake arm is mounted.
On reversing the eccentric, tappet, or other equivalent, the back draw bar will
be free, and the leading one locked; the vehicle can then travel in the opposite
direction, and the other brakes act in the manner before described.