IMPROVEMENTS IN THE CON- STRUCTION OF BUFFERS ADAPTED FOR RAILWAY CARRIAGES AND OTHER VEHICLES, AND AS A SUBSTITUTE FOR WEIGHT SPRINGS USED THEREWITH, AND FOR CHECKING THE RECOIL OF HEAVY GUNS
Year: 1869

page_text: LETTERS PATENT to John Goodjer Garrard, of Bishop's Stortford, in the
County of Herts, for the Invention of "IMPROVEMENTS IN THE CON-
STRUCTION OF BUFFERS ADAPTED FOR RAILWAY CARRIAGES AND OTHER
VEHICLES, AND AS A SUBSTITUTE FOR WEIGHT SPRINGS USED THEREWITH, AND
FOR CHECKING THE RECOIL OF HEAVY GUNS."
Sealed the 13th May 1870, and dated the 16th November 1869.
PROVISIONAL SPECIFICATION left by the said John Goodjer Garrard
at the Office of the Commissioners of Patents, with his Petition,
on the 16th November 1869.
I, JOHN GOODJER GARRARD, of Bishop's Stortford, in the County of
Herts, do hereby declare the nature of the said Invention for "IMPROVE-
MENTS IN THE CONSTRUCTION OF BUFFERS ADAPTED FOR RAILWAY CARRIAGES AND
OTHER VEHICLES, AND AS A SUBSTITUTE FOR WEIGHT SPRINGS USED THEREWITH,
AND FOR CHECKING THE RECOIL OF HEAVY GUNS," to be as follows:-
This Invention relates to that class of buffers in which compressed
air is employed as the resisting medium or elastic cushion for checking
the shock. Various methods have been attempted to construct buffers

page_text: on the above principle, and failed owing to the packing of the piston
not keeping air-tight under heavy pressure or sudden concussion.
Now the object and intention of this Invention is to enable the
packing to keep air-tight under any pressure or sudden concussion. I
propose to accomplish this by the following means:-I adapt to that
part of the piston of the buffer that is within the cylinder thereof two
discs or plates of metal convex on one side, the convex sides being
placed opposite to each other with an elastic cushion or thick washer of
vulcanized india-rubber, or its equivalent, placed between them, and
fitting the inside of the said cylinder. One of the aforesaid plates is
fixed and the other movable, the movable plate being nearest to the
closed end of the cylinder; the other end of the said cylinder is fitted
with a lid, through which the piston rod works, the buffer head being
fixed on the outer end of the said rod.
The effect of a buffer thus constructed is as follows:-Suppose the
cylinder to be charged with compressed air and pressure exerted on the
piston the effect will be to force the movable disc more closely against
the elastic packing, the pressure of the convex parts of the two discs on
the flat surfaces of the elastic packing being in proportion to the
resistance offered by the compressed air, and the force of the concussion
or pressure on the piston of the buffer thus keeping the edge of the
packing always in close contact with the cylinder, and ensuring an air-
tight packing; and it is this combination of two convex plates or discs
of metal acting upon an elastic cushion or washer placed between
them, as above stated, that constitutes the feature of novelty in this
Invention.

page_text: of our Lord One thousand eight hundred and sixty-nine, in the thirty-
third year of Her reign, did, for Herself, Her heirs. and successors, give
and grant unto me, the said John Goodjer Garrard; Her special licence
that I, the said John Goodjer Garrard, my executors, administrators,
and assigns, or such others as I, the said John: Goodjer Garrard,, my
executors, administrators, and assigns, should at any time agree with,.
and. no others, from time to time and at all times thereafter, during tho
term therein expressed, should and lawfully might make, use, exercise,.
and vend, within the United Kingdom of Great Britain and Ireland,.
the Channel Islands, and Isle of Man, an Invention for "-IMPROVEMENTS
IN THE CONSTRUCTION OF BUFFERS ADAPTED FOR RAILWAY CARRIAGES AND OTHER:
VEHICLES, AND AS A SUBSTITUTE FOR WEIGHT SPRINGS USED THEREWITH, AND FOR
CHECKING THE RECOIL OF HEAVY GUNS," upon the condition (amongst others),
that I, the said John Goodjer Garrard, my executors. or administrators,
by an instrument in writing under my, or their, or one of their hands.
and scals, should particularly describe and ascertain the nature of the
said Invention, and in what manner the same was to be performed; and
cause the same to be filed in the Great Scal Patent Office within six:
calendar months. next and immediately after the date of the said Letters.
Patent.
NOW KNOW YE, that I, the said John Goodjer Garrard, do hereby
declare the nature of the said Invention, and in what manner the same.
is to be performed, to be particularly described and ascertained in and.
by the following statement, that is to say:―
This Invention relates to that class of buffers in which compressed
air is employed as the resisting medium or elastic cushion for checking
the shock. Various methods have been attempted to construct buffers
on the above principle, and failed owing to the packing of the piston.
not keeping air-tight under heavy pressure or sudden concussion.
Now the object and intention of this Invention is to enable the
packing to keep air-tight under any pressure or sudden concussion. I
propose to accomplish this by the following means:-I adapt to that
part of the piston of the buffer that is within the oylinder thereof two.
discs or plates of metal convex on one side, the convex sides being placed
opposite to each other with an elastic cushion or thick washer of
vulcanized india-rubber, or its equivalent, placed between them, and
fitting the inside of the said cylinder. One of the aforesaid plates is.

page_text: fixed and the other movable, the movable plate being nearest to the
closed end of the cylinder; the other end of the said cylinder is fitted:
with a lid, through which the piston rod works, the buffer head being.
fixed on the outer end of the said rod.
The effect of a buffer thus constructed is as follows:-Suppose the
cylinder to be charged with compressed air and pressure exerted on the
piston the effect will be to force the movable disc more closely against
the elastic packing, the pressure of the convex parts of the two discs on
the flat surfaces of the elastic packing being in proportion to the
resistance offered by the compressed air, and the force of the concussion
pressure on the piston of the buffer thus keeping the edge of the
packing always in close contact with the cylinder, and ensuring an air-
tight packing; and it is this combination of two convex plates or
discs of metal acting upon an elastic cushion or washer placed between
them, as above stated, that constitutes the feature of novelty in this
Invention.
And in order to explain this Invention more completely I now
proceed to describe the means by which it may be carried into practical
effect, reference being had to the accompanying illustrative Drawing and
to the numeral figures and letters of reference marked thereon, as

page_text: on each side; I is a valve at which the cylinder A is charged with
compressed air by means of an air pump screwed in the place of the
plug K, the pump being removed after sufficient air has been compressed
into the cylinder; the plate E. will then be close against the lid B, so
that when pressure is exerted upon or against the end of the rod C,
which in the case of a buffer for a railway carriage has a head or plate
fixed thereon, the effect will be to still further compress the air that
is in the cylinder, the resistance of the air pressing the convex surface
of the plate G against the flat surface of the packing D, and acting in
like manner against the convex surface of the plate E will compress and
spread out the packing D, and cause its edge to press closely against
the inside of the cylinder A, thereby preventing the air from passing it,
and according to the amount of pressure on the outer end of the rod O
in like manner the packing will be pressed more or less closely against
the cylinder, enabling the buffer thus constructed to resist a pressure or
blow equal to 6 tons and more, according as the diameter of the
cylinder is increased in size.
At Figure 4, L is a leather cup within which the elastic washer or
packing D, shewn at Figure 3, fits so that the edge of the leather shall
be in contact with the inside of the cylinder instead of the edge of the
india-rubber, thereby enabling the packing to move more freely in the
cylinder under very heavy pressure.
In applying this buffer to carriages and other vehicles instead of
weight springs the body of the vehicle will rest on the ends of the
several rods C, there being several of such buffers suitably distributed.
For railway buffers and heavy guns the buffer will be placed hori-
zontally, and substantially fixed to resist or check concussion and
recoil.
Having thus described the nature and particulars of my said Inven-
tion, what I claim is, placing an clastic packing between two convex
plates, one fast and the other loose, on the end of a piston rod working
in a cylinder into which compressed air is forced, so that when pressure
is exerted on or against the outer end of the piston rod the resistance
of the compressed air shall force the convex surface of the plate or plates
against the flat surface of the clastic packing, thereby compressing it
and pressing the edge of the packing against the inside of the cylinder

page_text: with a force proportionate to the resistance of the compressed air,
substantially as above described and represented..
In witness whereof, I, the said John Goodjer. Garrard, have here-
unto set my hand and seal, this Thirteenth day of May, in
the year of our Lord One thousand eight hundred and seventy.
JOHN G. GARRARD. (L.S.)