IMPROVEMENTS IN STOP VALVES, ESPECIALLY SUITABLE FOR WATER PIPES
Year: 1878

page_text: LETTERS PATENT to Gerard Wenzeslaus von Nawrocki, of the Firm of J. Brandt
and G. W. v. Nawrocki, of 124, Leipzigerstrasse, Berlin, Germany, Engineers
and Patent Agents, for the Invention of "IMPROVEMENTS IN STOP VALVES,
ESPECIALLY SUITABLE FOR WATER PIPES." A communication from Armin
Bengen, of Berlin, Germany.
Sealed the 13th September 1878, and dated the 14th March 1878.
PROVISIONAL SPECIFICATION left by the said Gerard Wenzeslaus von
Nawrocki at the Office of the Commissioners of Patents on the 14th March
1878.
GERARD WENZESLAUS VON NAWROCKI, of the Firm of J. Brandt and G. W. v.
Nawrocki, of 124, Leipzigerstrasse, Berlin, Germany, Engineers and Patent Agents.
"IMPROVEMENTS IN STOP VALVES, ESPECIALLY SUITABLE FOR WATER PIPES." (A
communication from Armin Bengen, of Berlin, Germany.)
The object of this Invention is to construct valves in such a manner that they
shall be automatically self-closing, and so as not to cause the sudden blow to the
liquid column enclosed.
According to this Invention the fluid pressure holds the valve closed, and there
is a small auxiliary valve for partially letting off the pressure.
The valve casing consists of an upper and a lower part united by flanges,
between which is held an india-rubber diaphragm covering the inlet and outlet
below same. The space above the diaphragm communicates with the inlet by
means of a small passage, which can be closed more or less by means of an auxiliary
screw-down valve or plug; there is thus equilibrium of pressure above and below
the diaphragm, but the top area being larger than the bottom area of the diaphragm
the latter is down or closed. In the upper part of the casing there is a cock with
passages so arranged that it can establish communication between the inlet (by the
aforesaid auxiliary valve) and the outlet, or between the outer air and the outlet.
Or a valve made to press down by a knob or otherwise may be arranged in the
upper part of the valve casing instead of the aforesaid cock.

page_text: The action of this arrangement is as follows:-When the valve is closed there is
equilibrium above and below the diaphragm. On opening the auxiliary valve, at
the same time turning the tap (or depressing the valve knob, as the case may be)
so as to open communication between the outlet and the space over the diaphragm,
the water contained at the latter place will flow off, the pressure being thus taken 5
off the top of the diaphragm the pressure below will raise it and the water run
from the inlet to the outlet. To close the valve the cock is turned back into its
original position (or the valve knob released, as the case may be), the outlet being
thereby emptied, the equilibrium above and below the diaphragm will then
gradually be restored and the diaphragm depressed so as to close the outlet.
1
The gradual closing of the outlet, prevents the injurious blows caused by the
sudden arrest of the water column in the pipe.
SPECIFICATION in pursuance of the conditions of the Letters Patent filed by
the said Gerard Wenzeslaus von Nawrocki' in the Great Seal Patent Office
on the 14th September 1878.
GERARD WENZESLAUS VON NAWROCKI, of the Firm of J. Brandt and G. W. v
Nawrocki, of 124, Leipzigerstrasse, Berlin, Germany, Engineers and Patent Agents.
"IMPROVEMENTS IN STOP VALVES, ESPECIALLY SUITABLE FOR WATER PIPES." (A
communication from Armin Bengen, of Berlin, Germany.)
The object of this Invention is to construct valves in such a manner that they
shall be automatically self-closing, and so as not to cause the sudden blow to the
liquid column enclosed.
According to this Invention the fluid pressure holds the valve closed, and there is
a small auxiliary valve for partially letting off the pressure.
In the accompanying Drawings are shewn two modes of carrying out this
Invention.
Figure 1 is a longitudinal section, and Figure 2 a plan of one arrangement.
The valve casing consists of an upper and a lower part united by flanges,
between which is held an india-rubber diaphragm E covering the inlet and outlet
below same. The flanges on the upper and the lowor part and the diaphragm E
are held together by means of four screws a, and the diaphragm forms the joint
between the flanges. The space above the diaphragm communicates with the
inlet A by means of a small passage a', which can be closed more or less by means
of an auxiliary screw-down valve or plug F; there is thus, as shewn in Figure 1,
equilibrium of pressure above and below the diaphragm E, but the top area being
larger than the bottom area of the diaphragm the latter is down or closed. A is the
inlet and B the outlet. In the upper part of the casing there is a cock fitted with
screwed cap and packing; it is formed with passages so arranged that it can
establish communication between the inlet A (by the aforesaid auxiliary valve F)
and the outlet B, or between the outer air and the outlet. d is one slot or passage
through the plug C, and e is the other passage, which is slanting and leading to the
atmosphere.

page_text: Or according to a second arrangement, shewn in section in Figure 3, a valve C¹
made to press down by a knob or otherwise may be arranged in the upper part of
the valve casing instead of the aforesaid cock; in other respects the construction is
the same.
The action of this arrangement is as follows:-When the valve is closed, as here
shewn in both cases, there is equilibrium above and below the diaphragm, as the
passage e corresponds with the small passage b, which communicates with the
outlet B, the other end or e communicating with the air. When the valve is open
the passage b and slot & communicate with one another. When the valve is closed
to the inlet, then is equilibrium above and below the diaphragm E, as just stated.
On opening the auxiliary valve F, at the same time turning the tap C 90 degrees
round (or depressing the valve knob C, as the case may be) so as to open com-
munication between the outlet and the space over the diaphragm E, because the
slot & and the passage b communicate, the water contained at the latter place will
flow off; the pressure being thus taken off the top of the diaphragm F the pressure
below from the inlet A will raise it and the water run from the inlet A to the
outlet B. To close the valve the cock C, Figure 1, is turned back into its original
position (or the valve knob C, Figure 2, released, as the case may be), the passage b
is closed, and by the passage a the equilibrium above and below the diaphragm E
will then be gradually restored and the diaphragm depressed so as to close the
outlet. By the slanting passage e through the plug Ĉ the passage 6 and the
outlet B will now be emptied by the entry of air.
By adjusting the set screw F the opening of a¹ can be made smaller or larger,
and this affords a means for regulating the speed with which the valve is to close.
Referring specially to Figure 3, to open this valve, press on the knob C, the
valve c' in one therewith will then open and the space above the diaphragın E is in
communication with the passage b. Also in this case the pressure is taken off
valve and the passage is free right through. When the pressure on the knob C is
discontinued the valve c¹ will close by the water pressure of the main in A and a¹.
The closing of the diaphragin E takes place as described.
The gradual closing of the outlet prevents the injurious blows caused by the
sudden arrest of the water column in the pipe.
And having thus described the nature of this Invention I declare that I claim,
the construction of a valve which, closed by the water pressure in the main, the
space above and below a diaphragm communicating by a small passage, and the
automatic slow opening and closing of the valve being effected by opening and
closing of a small passage communicating with the outlet, all substantially as set
forth, and for the purpose of preventing injurious blows in the fluid column.
In witness whereof, I, the said Gerard Wenzeslaus von Nawrocki, have here-
unto set my hand and seal, this Ninth day of September, in the year
of our Lord One thousand eight hundred and seventy-eight.
GERARD WENZESIALIS FOV NAWROCKT