Flexible Metallic Couplings for Steam Heating Pipes, Compressed Air and Vacuum Brake Pipes.
Year: 1899

page_text: PROVISIONAL SPECIFICATION.
Flexible Metallic Couplings for Steam Heating Pipes, Compressed Air
and Vacuum Brake Pipes.
I, WOLFGANG SCHMID, of 17, Louisenstrasse, Munich, in the Empire of Germany,
Engineer on the Royal Bavarian State Railways, do hereby declare the nature
of this invention to be as follows:-
This improved flexible coupling differs from the couplings hitherto known by
its special construction and a quite peculiar tight closing of the joints.
The tight closing of the joints is made by membranous sleeves of india-rubber
or the like elastic material which are screwed with their ends between two
metal flanges. The tight closing of the joints is therefore a complete and lasting
one, without any particular finish of the joints and without the joints requiring
any subsequent grinding. These joints which have a circular ball joint movement
in so far as they are destined for steam-heating and compressed air brakes are
cup-shaped for the purpose of surrounding the membranous sleeves in such a way
that the latter everywhere rest on the cups and undergo no pressure.
By this arrangement in regard to the construction, great durabilty of the metal-
joints as well as of the membranous sleeves is provided for.
Practical experiments have proved that as regards complete air-tightness the
india-rubber sleeves after four months use are in no way strained and remain
perfectly elastic so that they will last a long time. The use of this metal-coupling
is still more favorable for compressed air- or vacuum-brakes in regard to the
durability of the india-rubber in as much as in this case the membranous sleeves
always remain elastic.
The metal-joints themselves need not be steam or air tight and thus may be
employed for years till some part of the same is worn out because the joints when
under the influence of the steam or air pressure are kept steady by the membranes
and are thereby not subject to any oscillations whilst the train is running.
The coupling consists of a double spherical or double-cup shaped shell, two
outer semi-spherical nuts, and two inner rounded ones a membranous sleeve and a
spiral-spring which is fastened with one end to each inner nut. The inner nuts
are soldered to the pipes to be coupled and can not be unscrewed. The mem-
branous sleeve of india-rubber is drawn over the inner nuts and afterwards for
the purpose of forming a tight joint they are firmly fastened by means of the
outer nuts. The double-cup-shaped shell is then put over the nuts and thereby
the joint is completed.
The steam or air-pressure employed presses the membranous sleeve against the
inner wall of the shell and the outer nuts are also pressed against the shell which
at these parts is also circular in form.
T
In unfastening the coupling, the pipes with the outer or spherical nuts are
moved within the cups of the shell. The membranous sleeve is thereby folded or

page_text: compressed together on one side and on the other side stretched out. As long as
the coupling is under pressure the joints remain in the straight position and there
is a straight passage of air or steam. Only when un-coupling are the joints moved.
These metal-couplings can be employed between railway-cars in every direction.
Another construction of the coupling may be made on the same principle. This
construction differs from the above described coupling in that both the shell and
the membranous sleeve consist of 2 parts, that is to say the shell at its middle is
screwed or bolted together. Furthermore the space between the membrane and
the spiral-spring is filled with an insulating material, (asbestos), for protecting
the membrane against the action of steam.
To show that there is a real need for a good metallic coupling it is only
necessary to point out two principal defects of india-rubber pipes, resulting from
the circumstance that india-rubber pipes are not made of pure india-rubber but
for the purpose of resisting the pressure of steam or air consist of different
layers of india-rubber and fabrics.
1. India-rubber pipes employed in connection with compressed air brakes may
endanger safety in running a train, in as much as in consequence of a loosening
of the inner layers of material the passage for steam or air may be stopped.
whereby the brakes cease to function. Such cases have already frequently
happened.
2. India-rubber pipes used as coupling for steam heating have the disadvantage
that they soon lose their flexibility on account of the different layers of canvas
and the like; they therefore soon become stiff and break.
In the construction of the above described couplings for steam heating, india-
rubber pipes cannot be usefully employed because they are no longer flexible
after being a short time in use. For vacuum brakes the improved coupling is
jointed in the following manner:--The construction of this joint is based on the
same principle as the herein before described joint for steam or compressed air
in as much as in this case also a membranous sleeve is employed for an absolutely
tight closing.
The spherical shells or cups are screwed to the pipes to be coupled and are
kept together by a bolt. The latter is screwed with one end into a cross piece in
the one pipe and has its other end which is ball shaped resting in a cross piece in
the opposite spherical shell. Thus the spherical shells move around the universal
joint formed by the ball end of the said bolt and are surrounded by the mem-
branous sleeve, the ends of which for the purpose of forming a tight joint are
nipped in by outer nuts which are screwed up. The membrane which is arranged
in folds is surrounded by a case to protect it against injuries. If the universal
joint be moved in any direction, the folds of the membrane on one side are
stretched out whilst on the other side the folds are folded together. In this joint
also therefore the membrane experiences no pressure as in case of an excess
pressure from outside and a vacuum inside the membrane rests against the cups.
Dated this 18th day of November 1899.
Of 6, Lord Street, Liverpool, Agents for the Applicant
COMPLETE SPECIFICATION.
Flexible Metallic Couplings for Steam Heating Pipes, Compressed Air
and Vacuum Brake Pipes.
I, WOLFGANG SCHMID, of 17, Louisenstrasse, Munich, in the Empire of Germany,
Engineer on the Royal Bavarian State Railways, do hereby declare the nature
AT LELE SPECIFICATION.
Flexible Metallic Couplings for Steam Heating Pipes, Compressed Air
and Vacuum Brake Pipes.
I, WOLFGANG SCHMID, of 17, Louisenstrasse, Munich, in the Empire of Germany,
Engineer on the Royal Bavarian State Railways, do hereby declare the nature

page_text: of this invention and in what manner the same is to be performed, to be particu-
arly described and ascertained in and by the following statement:―
This improved flexible coupling differs from the couplings hitherto known by
its special construction and a quite peculiar tight closing of the joints.
The tight closing of the joints is made by membranous sleeves of indiarubber
or the like elastic material which are screwed with their ends between two
metal flanges. The tight closing of the joints is therefore a complete and lasting
one without any particular finish of the joints and without the joints requiring
any subsequent grinding. These joints which have a circular ball joint move-
ment in so far as they are destined for steam-heating and compressed air brakes
are cup-shaped for the purpose of surrounding the membranous sleeves in such
a way that the latter everywhere rest on the cups and undergo no pressure.
By this arrangement in regard to the construction, great durability of the
metal-joints as well as of the membranous sleeves is provided for.
Practical experiments have proved that as regards complete air-tightness the
indiarubber sleeves after four month's use are in no way strained and remain
perfectly elastic so that they will last a long time. The use of this metal-coupling
is still more favorable for compressed air- or vacuum-brakes in regard to the
durability of the indiarubber in as much as in this case the membranous sleeves
always remain elastic.
The metal-joints themselves need not be steam or air tight and thus may be
employed for years till some part of the same is worn out because the joints when
under the influence of the steam or air pressure are kept steady by the membranes,
and are thereby not subject to any oscillations whilst the train is running.
In the accompanying drawings,
Figure 1 represents the flexible metal-coupling for steam heating and com-
pressed air brakes.
Figure 2 is a connecting piece for the steam or air-pipe.
Figure 3 is a section through a coupling which shows the absolute air-tight
closing of the joints.
Figure 4 is a front view of the coupling; whilst
Figure 5 represents a section of another construction.
Figure 6 represents the coupling for vacuum brakes.
The couplings consists of a double spherical or double-cup shaped shell a, two
outer semi-spherical nuts b, and two inner rounded ones c, a membranous sleeve d
The
and a spiral spring e which is fastened with one end to each inner nut c.
inner nuts c are soldered to the pipes f to be coupled and cannot be unscrewed.
The membranous sleeve of indiarubber is drawn over the inner nuts c and after-
wards for the purpose of forming a tight joint they are firmly fastened by means
of the outer nuts b. The double-cup-shaped shell a is then put over the nuts
and thereby the joint is completed.
The steam or air-pressure employed presses the membranous sleeve d against
the inner wall of the shell a and the outer nuts are also pressed against the
shell a which at these parts is also circular in form.
In unfastening the coupling the pipes f with the outer or spherical nuts b are
moved within the cups of the shell into the position shown in dotted lines in
Figure 1. The membranous sleeve is thereby folded or compressed together on
one side and on the other side stretched out. As long as the coupling is under
pressure the joints remain in the straight position and there is a straight passage
of air or steam, as shown in Figure 3. Only when uncoupling are the joints
moved. These metal-couplings can be employed between railway-cars in every
direction.
Another construction of the coupling may be made on the same principle, as
shown in Figure 5. This construction differs from the above described coupling
in that both the shell a and the membranous sleeved consist of 2 parts, that is to
say, the shell at its middle is screwed or bolted together. Furthermore the

page_text: space between the membrane and the spiral-spring is filled with an insulating
material, (asbestos), for protecting the membrane against the action of steam..
To show that there is a real need for a good metallic coupling, it is only
necessary to point out two principal defects of indiarubber pipes, resulting from
the circumstance that indiarubber pipes are not made of pure indiarubber, but for
the purpose of resisting the pressure of steam or air consist of different layers
of indiarubber and fabrics.
1. Indiarubber pipes employed in connection with compressed air brakes may
endanger safety in running a train, in as much as in consequence of a loosening of
the inner layers of material the passage for steam or air may be stopped whereby
the brakes cease to function. Such cases have already frequently happened.
2. Indiarubber pipes used as couplings for steam heating have the disadvantage
that they soon loose their flexibility on account of the different layers of canvas
and the like they therefore soon become stiff and break.
In the construction of the above described couplings for steam heating, india-
rubber pipes cannot be usefully employed because they are no longer flexible after
being a short time in use.
For vacuum brakes the improved coupling is jointed in the following manner:-
The construction of this joint is based on the same principle as the herein-
before described joint for steam or compressed air in as much as in this case
also a membranous sleeve is employed for an absolutely tight closing.
The spherical shells or cups a b, as shown in Figure 6, are screwed to the
pipes to be coupled and are kept together by a bolt f. The latter is screwed
with one end into a crosspiece in the one pipe c and has its other end which is
ball shaped resting in a crosspiece in the opposite spherical shell b.
Thus the spherical shells 12 b move around the universal joint e
formed by the ball end of the said bolt and are surrounded by the
membranous sleeve, the ends of which for the purpose of forming a tight
joint are nipped in by outer nuts 9 which are screwed up. The membrane which
is arranged in folds is surrounded by a case to protect it against injuries. If the
universal joint be moved in any direction, the folds of the membrane on one side
are stretched out whilst on the other side the folds are folded together. In this
joint also therefore the membrane experiences no pressure as in case of an excess
pressure from outside and a vacuum inside the membrane rests against the
cups.
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:
1. A flexible metal coupling with straight passage for steam-heating, com-
pressed air and vacuum brakes which is provided with a universal joint loosely
surrounded by the shell (ab), the closing of which is secured by an elastic
membranous sleeve (d) substantially as described.
2. In a flexible metal coupling with straight passage for steam heating, com-
pressed air and vacuum brakes provided with a universal joint, the arrange-
ment of a membranous sleeve d the ends of which are tightly connected by nuts
with the pipes (f) substantially as described.
3. A flexible metal coupling with straight passage for steam heating, compressed
air and vacuum brakes which is provided with a membranous sleeve (d) arranged
in such a way that the same experiences no pressure since by pressure from inside
the membranous sleeve (d) is pressed against the shells (a) whilst by pressure
from outside the membranous sleeve rests against the spherical shells (a b
Figure 6) substantially as described.
4. In a flexible metal coupling for steam-heating compressed air and vacuum
brakes provided with an universal joint, the arrangement of a spiral spring
(Figure 5) between the ends of the pipes and connected thereto for the purpose
of keeping the joint in a straight position substantially as described.

page_text: 5. In a flexible metal coupling for steam heating, compressed air and vacuum
brakes provided with an universal joint, the arrangement of an insulating
material, (asbestos, Figure 5) between the spiral-spring to protect the membranous
sleeve (d) against the action of steam substantially as described.
Dated this 15th day of August 1900
WM. P. THOMPSON & Co.,
Of 6, Lord Street, Liverpool, Agents for the Applicant