Improvements in Electric Brakes.
Year: 1899

page_text: Date of Application, 24th Apr., 1899-Accepted, 10th June, 1899
Improvements in Electric Brakes.
I, GEORGE HENRY BINGHAM HOOPER, of 8, Treford Place, in the City of Toronto,
in the County of York, in the Province of Ontario, Canada, Electrician, do hereby
declare the nature of this invention, and in what manner the same is to be per-
formed, to be particularly described and ascertained in and by the following state-
ment:-
My invention relates to improvements in electric brakes for car and other wheels
and the object of the invention is to design a simple and effectual form of brake
shoe in which the lines of force passing through the ends will act with the greatest
strength upon the perimeter of the wheel and it consists essentially of a brake
shoe having the major portion of the magnet formed on a circle having a less arc
than the contacting pole ends, which are formed concentric to the centre of the
wheel to which the brake is applied and extend out entirely beyond the wound
portion of the magnetic shoe, the parts being otherwise constructed and arranged
in detail as hereinafter more particularly explained.
Fig. 1, is a side elevation showing the application of my brake to a wheel.
Fig. 2, is a sectional plan of the brake-shoe and portion of the wheel showing
the means whereby such brake shoe is normally held from contact with the wheel.
Fig. 3, is a detail of an alternative form.
In the drawings like letters of reference indicate corresponding parts in each
figure.
A is a wheel having an iron rim and designed to be a wheel of a car or other
vehicle or a wheel on a shaft or any other wheel to which it is necessary to apply
a brake. B is my brake shoe comprising a magnet portion B' wound as specified
and the end contacting pole portions B².
It will be noticed that the pole portions B2 extend outwardly entirely to the
outside of the magnet portion B₁ and are formed in arcs concentric to the perimeter
of the wheel.
The portion B¹ it will be noticed is formed on an arc described from a less
radius than that of the ares of the pole ends. By providing outwardly extending
pole ends as described the magnetic lines of force are allowed a freer passage to the
perimeter of the wheel and being entirely outside of the portion 13 there is no
danger of short circuiting between the poles as would be the case if the poles
approached each other or were. close together.
The magnetic brake shoe is held in position by a link C pivotally connected to
the top of the shoe and suspended from a loop D. E are the wires running to the
wound portion, which wires are provided at any convenient point with a suitable
switch to throw the current into the magnet when desired.
The magnetic shoe B is held from lateral displacement by the hanger F provided
with the jaws f between which the shoe fits.
In order to hold the shoe positively free of the wheel I provide an elastic band f¹,
which is passed around the magnet at one end and a hook f on the hanger F
at the opposite end.

page_text: It will be noticed in Fig. 3, that I provide a straddling bracket G, which I bolt
at each end to the core of the magnet. The rod G¹ connects the bracket G to the
opposite bracket and the brake is supported by a link as hereinbefore shown.
The brake levers and shoes will be connected to this rod as in any other brake and
such brake could then be put on by hand if desired.
It will be seen from this description by the construction of my brake shoe that
I am able to procure a very much better grip upon the surface of the wheel
than those heretofore devised of which I am aware.
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:-
1. A brake for wheels comprising a bar magnet of uniform cross section through-
out, having the wound portion formed on a core, the arc of which is that of a
circle less than that of the rim of the wheel to which it extends, pole ends extending
entirely outside such arc and formed on arcs concentric to the perimeter of the
wheel and having their inner arc-shaped sides disposed to contact with the wheel,
as specified.
2. A brake for wheels comprising a bar magnet having the wound portion formed
on a core, the arc of which is that of a circle less than the arc of the rim of the
wheel to which it extends, pole ends extending entirely outside such are and
formed on ares concentric to the perimeter of the wheel and having their inner
arc-shaped sides disposed to contact with the wheel, a link supporting the same
pivotally connected at the bottom to the top of the arc-shaped pole end thereby
leaving the opposite pole end perfectly free and the inner side of both pole ends
disposed to contact with the wheel, a rigidly supported guiding hanger having the
bottom end embracing the central portion of the core and limiting its movement,
and a suitable spring connected to the magnetic brake shoe at the centre and to a
suitable portion of the hanger at the opposite end, as specified.
3. A brake for wheels comprising a bar magnet of uniform cross section through-
out, having the wound portion formed on a core, the arc of which is that of a
circle less than that of the rim of the wheel to which it extends, pole ends extending
entirely outside such are and formed on arcs concentric to the perimeter of the
wheel and having their inner arc-shaped sides disposed to contact with the wheel,
the links supporting the bar magnet at the top and the straddle bracket secured
to the ends of the core and provided with a cross rod as and for the purpose specified.
T
G. F. REDFERN & Co.,
4, South Street, Finsbury, London,
Agents for the Applicant.