An Apparatus for Indicating the Flow of Fluid, chiefly designed for use as an Indicating Feed-water Check-valve.
Year: 1892

page_text: Date of Application, 6th July, 1892
Complete Specification Left. 1st Apr., 1893-Accepted, 6th May, 1893
PROVISIONAL SPECIFICATION.
An Apparatus for Indicating the Flow of Fluid, chiefly designed for
use as an Indicating Feed-water Check-valve.
I, HIRAM STEVENS MAXIM, of Baldwyn's Park, Bexley, in the County of
Kent, Mechanical Engineer, do hereby declare the nature of this invention to be
as follows:-
My invention relates to an apparatus for indicating the flow of fluid, and which
is chiefly designed for use as an indicating feed-water check-valve
My said invention is applicable with especial advantage to the feed-water check-
valves of steam boilers, particularly to steam boilers in which the evaporation is
extremely rapid. It is very desirable to be able, in such boilers, to determine with
readiness and certainty, whether water is or is not entering the boiler, by some
better means than applying the hand to the feed-pipe.
My invention not only enables the boiler attendant to know whether water is or
is not passing into the boiler, but, in addition, indicates the amount of fluid passing
the valve on its way to the boiler.
According to my invention a tube is secured within the casing or shell of the
valve in such a position that all the fluid which passes into the shell or casing must
enter the said tube, from which the only exit of the fluid is by way of perforations
or slots provided in the wall of the tube, or by way of a passage or passages
provided in or in connection with the said tube, for example as hereinafter described.
At the end of the said tube at which the supply pipe or feed pipe delivers fluid
thereinto, is a suitable seating for a disc or piston, which, when resting on the said
seating, acts to prevent the return of fluid into the supply pipe or feed pipe thereby
constituting a check valve, and which also fits closely but easily within the said
tube, in which it is adapted to slide in the direction of the axis thereof. In the
wall of the tube are a large number of small perforations or slots, for example,
through which the fluid delivered by the supply pipe or feed pipe passes, after
moving the said disc or piston from its seat through a distance sufficient to uncover
a suitable number of them. Or, as an alternative the disc or piston may be arranged
so that it acts as an indicating device and not as a check valve; in such a case its
movement is limited by suitable stops, and a seating need not be provided.
Moreover the said disc or piston may have a clearance around it, so that it does not
fit the interior of the aforesaid tube. A rod or pointer is secured to or operated
by the disc or piston and is arranged to move over a scale so as to afford, outside
the valve casing, an indication of the flow of fluid through the said casing. For
example, a rod secured to the disc or piston may extend through the cover of the
shell of the valve or indicating device into a glass tube secured upon the outside
thereof and provided with a scale upon which is marked the rate of supply corre-
sponding to the position, at any time, of the end of the rod with reference to the
said scale. A suitable guide is provided at the place at which the rod passes
through the shell; the lower end of the glass tube bears upon a packing ring
placed upon the cover, and the upper end thereof has a packing washer held down
upon it by a cross-head, which is secured to, the shell of the valve by long bolts and
serves to keep the glass tube and its packing in place.
The underside of the valve cover is preferably formed with a seating, so that in
case of the accidental breakage of the glass tube, the piston or valve will be forced
up and will come into close contact with the said seating so as to prevent escape of
the water or other fluid.
In large valves, for marine boilers for example, a pointer moving over a segmental

page_text: or circular scale may be provided, to be operated by the disc or piston instead of
the rod moving in a glass tube as aforesaid.
In some cases, instead of employing a perforated tube as aforesaid, the tube may
be made taper and without perforations; movement of the disc or piston will then
afford a variable annular opening for the passage of fluid around the said disc or
piston and between it and the wall of the taper tube.
Dated this 6th day of July 1892.
HASELTINE, LAKE & Co.,
45, Southampton Buildings, London, W.C., Agents for the Applicant.
:
COMPLETE SPECIFICATION.
An Apparatus for Indicating the Flow of Fluid, chiefly designed for
use as an Indicating Feed-water Check-valve.
I, HIRAM STEVENS MAXIM, of Baldwyn's Park, Bexley, in the County of
Kent, Mechanical Engineer, do hereby declare the nature of this invention and in
what manner the same is to be performed to be particularly described and ascer-
tained in and by the following statement :-
My invention relates to apparatus for indicating the flow of fluid, said apparatus
being chiefly designed for use as an indicating feed-water check-valve.
My said invention is applicable with especial advantage to the feed-water check-
valves of steam boilers, particularly to steam boilers such as torpedo boat boilers
in which the evaporation is usually extremely rapid. It is very desirable to be
able, in such boilers, to determine with readiness and certainty whether water is
or is not entering the boiler, by some better method than that of testing the
temperature of the feed-pipe by applying the hand thereto. My invention not only
enables the boiler attendant to ascertain at a glance whether water is or is not
passing into the boiler, but in addition, indicates the amount of fluid passing the
valve on its way to the boiler.
In the accompanying drawings I have shown how my invention may be advan-
tageously carried into practice.
Figure 1 is a side elevation of one form of my improved indicating check-valve,
and
Figure 2 is a vertical central section through the indicating chamber thereof.
Figure 3 is central section of a slightly modified form of indicating check-valve
constructed according to my invention.
Like letters of reference denote corresponding parts in all the figures.
A is the valve body or casing; A¹ is the inlet; A is the outlet. The check-
valve shown in Figures 1 and 2 is combined with an ordinary stop valve. Such
valve may be a butterfly valve, or a screw-down or other well known type
of valve.
I secure within the casing or shell A a cylindrical tube B in such a position that
all the fluid which passes into the shell or casing must enter the said tube, from
which the only exit for the fluid is by way of perforations or slots B¹ provided in
the wall of the tube. In the construction shown in Figure 2 the tube B is
screwed into the casing at its upper end at B2. The lower end of the tube fits
tightly into a recess A³ provided in the casing to receive it. In the check-valve
shown in Figure 3 the tube B screws into the casing at its lower end, and is open
at its upper end. At the lower end of the said tube there is a seat B³ for a disc
or piston C which disc, when resting on the said seat, acts to prevent the return
of fluid into the supply-pipe or feed-pipe, thereby constituting a check-valve. The
said disc or piston fits, closely but easily within the tube B in which it is adapted
to slide in the direction of the axis thereof. The fluid delivered into the tube B
by the supply-pipe or feed-pipe, passes out through the perforations or slots B¹
after raising the disc or piston C from its seat through the required distance to
uncover a sufficient number of said perforations or slots.

page_text: A rod C secured to the disc or piston-C extends through a hole A° in the lid
or cover A of the valve casing and projects into a strong glass tube D. The glass
tube in Figures 1 and 2 is secured in place, within a skeleton extension A' of the
lid A, by a nut A and lock nut A7. Suitable packing rings D' D' are provided.
to prevent leakage of the fluid at the ends of the tube. E is a scale secured to
the extension A3 upon which scale is marked the rate of supply corresponding to
the position, at any time, of the end of the rod C¹ with reference to the said scale..
For greater accuracy the indicating point on the rod C¹ Figure 2 is a bevelled
edged disc C2, which is secured to the end of the rod. F is a vent plug which is
screwed into the nut A. It is made with an expanded part F¹ forming a valve
adapted to be screwed down tightly on to the countersunk end of the hole in the
nut A to close the said hole. A small passage F2 is made through this vent plug
opening out at the side of the plug just underneath the part F. By unscrewing
the plug, a vent is made that permits of the escape of air from the glass tube D.
In the modification shown in Figure 3 the glass tube D is supported between the
lid A and a head G which is secured to the said lid A by bolts G. Packing
rings D are provided to prevent leakage at the ends of the tube.
The underside of the lid is preferably formed with a seating A Figure 3 so that.
in case of the accidental breakage of the glass tube D, the piston or valve will be:
forced up and will come in close contact with the said seating so as to prevent.
escape of the water or other fluid. In large valves, for marine boilers, for
example, I prefer, instead of the rod C' moving in a glass tube D as hereinabove
described, to provide a pointer moving over a segmental or circular scale to be
operated by the disc or piston through the intervention of an oscillating or rotating.
shaft passing through a stuffing-box in the casing. In some cases I construct the
disc or piston so that it acts as an indicating device but not as a check-valve; in.
such a case its movement is limited by suitable stops, and a seat need not be
provided. The disc or piston may have a clearance around it so that it does not.
fit the interior of the tube.
I have described and shown a moving valve or disc in combination with a per-
forated stationary cylinder, but it is obvious that I may somewhat modify this.
construction as follows, that is to say, I may make the valve or disc and perforated
cylinder in one, or if separate, firmly secure the two together, and so construct the.
seat that the perforated cylinder will rise and fall through the seat and thus.
afford according to its position a larger or smaller opening for the passage of the
fluid.
In a modification of my invention, instead of employing the perforated cylin-.
drical tube B I employ a taper tube without perforations but open at the end;
the movement of the disc or piston in such case will afford a variable annular
opening for the passage of fluid around the said disc or piston and between it and
the wall of the taper tube, and hence the position of the disc or piston will adjust.
itself in accordance with the quantity of fluid passing.
Having now particularly described and ascertained the nature of my said inven-
tion and in what manner the same is to be performed, I declare that what I
claim is :-
1. The combination, with a check-valve, of a perforated cylindrical tube in
which the valve proper is adapted to move, and an indicating rod or its equivalent.
connected with the valve, for the purpose specified.
2. Apparatus for indicating the flow of fluid comprising a casing, a perforated
tube in said casing, a disc or piston adapted to move axially in said tube, and an
indicating rod or its equivalent connected with said disc or piston, substantially as
described.
3. The modification of my invention wherein the perforated cylinder is formed.
with or secured to the valve and moves through the valve seat, substantially as
described.

page_text: •
4. The modification of my indicating device wherein I use a conical plain tube
in lieu of the perforated tube, substantially as specified.
5. An indicating check-valve constructed substantially as described with
reference to Figures 1 and 2 or to Figure 3 of the accompanying drawings, and
operating as, and for the purpose, specified.
Dated this 1st day of April 1893.
HASELTINE, LAKE & Co.,
45, Southampton Buildings, London, W.C., Agents for the Applicant.