IMPROVEMENTS IN LOCOMOTIVE BRAKES
Year: 1882

page_text: LETTERS PATENT to William Moray Lendrum of Blatherwicke in the County
of Northampton. for an Invention of IMPROVEMENTS IN LOCOMOTIVE BRAKES
Communicated to him from abroad by Samuel C. Sloan of New York in the
United States of America
PROVISIONAL SPECIFICATION left by the said William Moray Lendrum at
the Office of the Commissioners of Patents on the 27th September 1882.
WILLIAM MORAY LENDRUM of Blatherwicke in the County of Northampton
"IMPROVEMENTS IN LOCOMOTIVE BRAKES " [Communicated to him from abroad
by Samuel C. Sloan of New York in the United States of America]
This invention relates to apparatus for working the brakes of locomotive engines,
the chief object being to balance and equalise the strains of the brake blocks on
the wheels so that the axles and bearings are entirely relieved from the pressure of
the brakes when they are applied. For this purpose each driving wheel is provided
with two brake blocks one on each side of it arranged as nearly as possible in the
horizontal line of the centre of the wheel and all these brake blocks are connected
with one brake shaft and lever by which they are worked simultaneously, the
levers being proportioned in such a manner as to throw on each block an equal
strain.
$

page_text: :
SPECIFICATION in pursuance of the conditions of the Letters Patent filed
by the said William Moray Lendrum in the Great Seal Patent Office on the
19th March 1883.
"
3
WILLIAM MORAY LENDRUM of Blatherwicke in the County of Northampton
IMPROVEMENTS IN LOCOMOTIVE BRAKES A communication to me from abroad
by Samuel C Sloan of New York in the United States of America
This invention relates to apparatus for working the brakes of locomotive engines,
the chief object being to balance and equalize the strains of the brake blocks on
the wheels, so that the axles and bearings are entirely relieved from the pressure of
the brakes when they are applied. For this purpose, each driving wheel is provided
with two brake blocks, one on each side of it arranged as nearly as possible in the
horizontal line of the centre of the wheel, and all these brake blocks are connected
with one brake shaft and lever by which they are worked simultaneously, the
levers being proportioned in such a manner as to throw on each block an equal
*strain.
DESCRIPTION OF THE DRAWINGS
Fig. 1 of the accompanying drawings is a side view and Fig. 2 is a plan of the
underframing of a six-wheeled locomotive, shewing the arrangement of brakes and
their levers and connections, according to this invention, so as to equalise the strain
of the brake blocks on the peripheries of the several wheels, and to avoid lateral
strain on the axles when the brakes are applied. The braking power, usually given
by screw gear or by a piston moved by fluid pressure on the tender, is transinitted
equally by the two rods A A, one on each side, to the middles of the two diagonal
levers D¹. The lower end of each of the levers D' is linked to the lever C¹ which
is pivotted on a bracket E projecting down from the framing, and which carries
the brake block B¹ jointed to its upper end. The upper end of the lever D¹ is
linked by a rod F¹ to the upper end of the next diagonal lever D2, the lower end
of which is linked to the second brake lever C2 carrying the brake block B². The
lever C is pivotted on one end of a bar G¹ which can be adjusted longitudinally
and secured by setting screws, and which has pivotted at its other end the next
lever C³ carrying the brake block B³. The middle of the lever D2 is linked to the
middle of a corresponding lever D³, the lower end of which is linked to the lever C³,
while its upper end is linked by the rod F2 to the lever D. Here the connections
of D to D and of these to the levers C4 C5 carrying the brake blocks B* B³ are
arranged similarly to those of D2 D³, C² C³, and B2 B³. Again, the upper end of
-the lever D³ is linked by the rod F³ to the upper end of D6, the lower end of which
is linked to the lever C carrying the brake block B. The middles of the levers C
on each side are connected by chains or rods G to the ends of a sway beam H,
the middle of which is secured to the framing through a strong spring J. The
system of levers and connections is such that whatever be the strain transmitted
by one of the rods A A, half of that strain is applied to each of the brake
levers,C¹ C² &c., and consequently each of the brake blocks B¹ B² &c. is applied with
the same pressure against the wheel periphery. Moreover, by means of the sway
beam H, the strain and movement of the brakes on each side of the locomotive are
equalised. Again, as each wheel is subjected to equal pressures of the brake blocks
on each side of it, there is no lateral strain on the axles or their boxes when the
brakes are put on.
Although the arrangement has been described as applied to a six-wheeled

page_text: locomotive, it can obviously be applied in a similar way to a four-wheeled locomotive
by simply omitting the system of levers and links for the middle wheels.
Having thus described the nature of this invention and in what manner the
same is to be performed as communicated to me by my foreign correspondent, I
claim
The arrangement of levers and connections applying equal strains of brake
blocks on both sides of each locomotive wheel, substantially as and for the purposes
herein set forth.
In Witness whereof I the said William Moray Lendrum have hereunto set
my hand and seal this Sixteenth day of February in the year of our Lord
One thousand eight hundred and eighty-three.
WILLIAM MORAY LENDRUM. (L.S.)