IMPROVEMENTS IN AIR SPRINGS OR BUFFERS
Year: 1884

page_text: I, Baron WILLIAM DE WAGSTAFFE of 75 Cambridge Terrace, in the County of
Middlesex do hereby declare the nature of my invention for 'IMPROVEMENTS
IN AIR SPRINGS OR BUFFERS' and in what manner the same is to be performed
to be particularly described and ascertained in and by the following statement
-
My invention relates to air springs primarily designed for use as springs for
ailway-carriages or other vehicles but also applicable as buffers for railway vehicles
or railroad termini, the said springs are moreover adaptable for various other uses
where a confined body of aeriform fluid is required to soften or deaden concussion
The porous nature of the india rubber leather and other non metallic substances
heretofore used in the construction of such springs, has rendered them incapable of
confining the air and preventing its escape Moreover the means or appliances
heretofore designed for supplying air to make up any deficiency, have been neither
effective nor reliable
The object of my invention is to produce a spring or buffer in which the ur will
be effectually confined and retained, and which will possess all the elasticity and
strength necessary or desirable in an air spring or buffer
In the accompanying drawing,
Figure 1 18 a longitudinal section of a spring for a railway vehicle constructed
in accordance with my said invention
Figure 2 is a plan or top view of the said spring, with some of the parts
removed
Figure 3 is a longitudinal section of a modified form of spring constructed in
accordance with my invention and more particularly adapted for railway wagons
Figure 4 is a plan of the spring shown in Figure 3
Similar letters of reference indicate corresponding parts in the several figures
Referring to Figure 1, A is a part of the frime work of the truck of a railway
carriage, B is a part of the frame of the body thereof C and C are the lower
and upper parts of a metal case which may be of any suitable shape or description.
In the device shown the case is cicular as seen in the plan Figure 2 The lower
part C of the case is recessed at its under side to fit the part A of the frame work
Гомал с

page_text: of the truck Within the case CO 18thin dished shoet or plate a of steal,
hardened brass or other suitablo motal the flange all of which plato rests upon
and extends nearly to the outer limit or edge of, the part C of the case
An
inverted dish or curved diaphragm plato a', also made of a thin plato of steel,
hardened brass, or other suitable metal is placed above the dished plate a, its
Aango a resting upon the flange a" The two parts OO of the case are hold
or clamped together, and an air tight joint made at the flanges a", a", by means
of a series of bolts b The central portion of the diaphragm a' is recossed to form
a concave seat for the plate or enlarged head o of the bolt c³, and a convex seat for
the lower flange c¹¹ of the alcove c, whose upper flange o serves to support the
part B of the frame of the body of the vehicle The nut d servos to clamp the
diaphragm plate a' tightly between the enlarged heal o aud the flange The
upper part of the flango ol is provided with an annular groove or channel within
which is inserted an india-rubber ung e
At the centre of the dished plate a is formed a depression e¹ Bulow the said
depression is a pipe or tube e" which is passed though the fi ime work A
and the section C of the case The pipe or tube is connected with a pipe ell
extending to an air pump or other device for supplying au to the spring for
example the pump used as a part of an air brake system, or the pipo may be
connected with any source of air supply such as n roservou holding air under
pressure Within the depression e' is fitted the head of valve or plug having
a stem which pisses longitudinally through the pipe or tube e", and is provided
at its outer end with a screw threaded portion on which is screwed a nut c The
pipe or tube e¹ has a diameter greater than that of the stem e, so that an annular
air channel is provided within the said tube and around the said stem, with which
annular channel the air pipe el is connected By means of the nut es, which benis
against the solid end of the pipe or tubo o", the ho id e' of the valve can be tightly
drawn into the depression e', and a tight joint made at tho said depression
head of the valve or plug may be packed by the interposition of any suitable
material.
The
Referring to Figures 3 and 4, a a' are the lower and upper sections of the
spring which are made of thin plates of steel, hardened brass, or other suitable
metal, and which have flanges a", a These flanges are clamped between the
rings or annular pieces C, C' The outer or peripher il portions of the plates a, a¹
as seen in transverse section, ale of circular form like the corresponding part of the
plate a' in Figure 1 In the apparatus shown in Figure 1, the plates a, a' at all
portions of their surface or area are of the same thickness and movement of the
upper or diaphragm plate a' only is provided for In the apparatus shown in
Figures 3 and 4, however, the parts of the plates a a', within or surrounded by
the outer or poipheral portions, increase in thicknoss towards the centro where
hubs a are formed As in Figures 1 and 2, the plates a, a¹ are securely attached
to the paits 00' by a series of bolts b, and in both the modifications shewn in
Figures 1 and 3 the tightness of the joint at the flanges is enhanced or onsured by
an angular bend a and a conformation of the two parts C C to adapt them to the
said bend In Figure 3 the au valve, tube, and air pipe are of substantially the
same construction as in Figure 1, but in Figure 3 the entire valvo arrangement is
attached to the lower spring plate a
In operation, the spring, whether of the form shewn in Figure 1 or that shown
in Figuro 3 is charged with air of the required density This is accomplished as
follows, that is to say, the nut is loosened to permit the hond e' to rise from the
depression or seat made to receive it. Au is then pumped, or otherwise introduced
into the spring through the pipe e¹¹ After the sping has been properly chaiged
with au, and while the pipe is still in communication with tho source of supply
or pressure, the nut is tightened so as to draw the head e' of the valve into its
depression or seat thus scaling or closing the interior of the spring against all
communication with the outci au

page_text: The joints at the flanges a¹, all and around the bolts b, may, if desired, be
tightened by any convenient additional means. If necessary, permanent joints
may be made at the flanges all, all, by brazing or otherwise, and the bolts may
also be sealed by the interposition of any packing or other substance.
The object of the dished plate a in Figure 1, is to prevent the escape of air
through the pores of the section C of the casing rather than to act as a part of
the spring. It is well known that it is practically impossible to produce a casting
of iron which will be perfectly proof against the escape of air confined within it
under great pressure. Hence the dished plate a made of a thin plate of steel,
hardened brass, or other equivalent metal of great density, is used as an auxiliary
to the casting to confine the air.
Therefore the upper plate a¹ in Figure 1 is the only one capable of movement
during the action of the spring, and it will move cushioned by the confined air,
and counteract or deaden any jar or shock between the truck and the body of the
vehicle.
The function of the india-rubber ring e is to act in connection with the surface f
of the part C¹ to prevent shock or undue concussion on a sudden outward
movement or distention of the parts of the spring.
In Figure 3, however, both plates a a¹ serve as parts of the spring proper and
partake equally of the movement.
I can adapt my invention to various uses both as a spring and as a buffer.
In my spring, the central portions of the receiver are practically rigid while
the surrounding parts are flexible. In this respect my invention differs essentially
from other springs in which the movement under strain, or compression, effects the
collapse or distention of all parts of the metallic receiver in an equal.degree..
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 :-
First. An elastic metallic spring or buffer consisting essentially of a receiver
rigid at its centre and flexible at its periphery, and adapted to surround or enclose
a body of compressed air, substantially as set forth.
Second. A hollow elastic metallic spring consisting essentially of a receiver rigid
at its centre and flexible at its periphery and filled with compressed air, combined
with means for attachment to the truck and body of a railway-carriage or other
vehicle, substantially as set forth.
Third. In an elastic metallic spring or buffer constructed substantially as above
described, the employment of the pipes and valve whereby compressed air may be
admitted to the interior of the spring and retained therein, substantially as
set forth.
Fourth. In an air spring or buffer, a metallic plate or diaphragm rigid at its
centre and flexible at its periphery, combined with the frame of the body of a
railway-carriage or other vehicle, substantially as set forth.
Fifth. In an air spring or buffer, a cast iron case, and a thin sheet or plate of
steel, hardened brass, or other suitable material, to render the cast iron case proof
against the escape of compressed air, combined with a metallic diaphragm adapted
to be connected with the body of a railway-carriage or other vehicle, substantially
as, and for the purpose, set forth.
Sixth. In an air-spring, the combination of a case, a metallic plate or diaphragm
rigid at its centre and flexible at its periphery, and a sliding connection between
the said plate or diaphragm and the body of a railway-carriage or other vehicle,
substantially as set forth.
Seventh. In an air-spring, the combination of a case, a hollow metallic spring
enclosed thereby, the said spring being rigid at its centre and flexible at its
periphery, and a connection between the said spring and the body of a railway-
carriage or other vehicle, substantially as set forth.

page_text: Eighth. In an air-spring, the combination of a case, a hollow elastic metallic
spring enclosed thereby, a sliding connection between the said elastic spring and
the body of a railway-carriage or other vehicle, and an interposed body of india-
rubber or other suitable material, to absorb or deaden the concussion between the
spring and case, substantially as set forth.