Year: 1886

page_text: Date of Application, 20th Aug., 1888.
Complete Left, 17th May, 1887.
Complete Accepted, 17th June, 1887.
I, WILLIAM HAMILTON BLAKENEY of Eden Grove, Dundee, do hereby declare the
nature of this invention to be as follows:-
The object of my invention is to equalize the pressure on the brake blocks of
tramway cars. This I effect by constructing the lever and connecting rod mechanism
of the brakes in such a manner that the effort or pressure exerted on any one wheel
or pair of wheels by any one block or pair of blocks is obtained through or in virtue
of the resistance set up by the abutment of a similar block or pair of blocks on
another wheel or pair of wheels. In this invention no single block can exercise any
material amount of pressure on a wheel until the whole of the blocks are in
actual contact with their respective wheels and in a position to act as abutments or
fulcra to each other.
The levers and connecting rods, which in their general arrangement may be the
same as is generally in use on tramcars, are provided at their points of attachment
with each other and with the car with slots or simple movable joints. These slots and
joints admit of sufficient adjusting motion being given to the levers and rods in
the particular plane necessary for the equal distribution of the dragging or breaking
effort.
In lieu of slots or loose joints a chain or link may be used to suspend the whole
brake mechanism thus allowing of free play and the balancing of the braking
effort.

page_text: I, WILLIAM HAMILTON BLAKENEY of Edengrove, Dundee, in the County of Forfar,
N.B. Draper, 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:-
The object of my invention is to balance, equalize, or distribute the pressure on the
brake blocks of tramway cars.
This I effect by constructing the lever and connecting rod mechanism of the brakes
in such a manner that the effort or pressure exerted on any one wheel or pair of
wheels by any one block or pair of blocks is obtained through or in virtue of the
resistance set up by the abutment of a similar block or pair of blocks on another
wheel or pair of wheels. In this invention no single block can exercise any material
amount of pressure on a wheel until the whole of the blocks are in actual contact with
their respective wheels, and in a position to act as abutments or fulcra to each
other.
The levers and connecting rods, which in their general arrangement may be
substantially the same as is generally in use on tramcars, are provided at their points
of attachment with each other and with the car with slots or simple movable joints.
These slots and joints admit of sufficient adjusting motion being given to the levers
and rods in the particular plane necessary for the equal distribution of the dragging
or braking effort.
At Fig. 1 Sheet 1 is shown the general arrangement of connecting rods and
attachments which may be used in connection with my invention. At a Figs. 1 and 2
Sheet 1 is shown the ordinary lever which serves to operate both pairs of wheels of
an ordinary tramcar. At 6 Figs. 1 and 2 Sheet 1 is shown the attachment of this
lever to the car. At c Fig. 2 Sheet 1 is shown a slot in the lever which ongages with
a bolt attached to b. This slot allows of a certain amount of motion to the whole bar,
being capable of sliding within the limit of its length on the bolt attached to b. In
lieu of the slot and attachment a hanging joint or chain as shown at Figs. 6 and 7
Sheet 2. or a simple strap carried over the bar without a bolt attachment as shown at
Fig. 4 and 5 sheet 2. or such other device may be employed as will allow of a certain
but not excessive amount of play to the whole bar in the plane of its ordinary motion.
At d. d. Figs. 1 and 2 Sheet 1 are shown the ordinary rods used to connect the
central bar with the block bars e. e. Fig. 1 Sheet 1. At f. f. Fig. 1 Sheet 1. are
shown the rods which serve to convey the braking force from the handles.
My invention operates in the following manner;
On force being applied, all the blocks take up a position touching the wheels, and
no material pressure can be applied to any block until all are in touch with the
wheels, in virtue of the adjusting motion allowed by the slot, chain-joint, strap, or

page_text: other device. When the blocks have taken up a position the braking effort sub-
sequently applied is equally distributed to the wheels, each of the blocks acting as a
point of resistance or abutment for the action of the other blocks. In this manner
the force is equally distributed between the wheels. The blocks at each end of the
bars e. e. Fig. 1. Sheet 1 adjust themselves through the elasticity of the fastenings
and the rods d. d.
Having now particularly described and ascertained the nature of my said invention,
and in what manner the same is to be performed I declare that what I claim is ;
1st. The combination of hanging joint, strap, slot, or similar device with the brake
mechanism of street tramway cars in such a manner as to balance, equalize, or
distribute the pressure or braking effort on the wheels, substantially as described.
Dated this 12th day of April 1887.