Year: 1898

page_text: I, JOSEPH NUTTING, of Balham Grove, Balham, in the County of Surrey, Timber
Merchant, do hereby declare the nature of this invention to be as follows:-
The object of my invention is a whistle, blown by steam or air to give warn-
ing when the pressure in a boiler or other vessel or pipes exceeds the desired
amount.
The devices in use for this purpose at the present time are actuated by floats and
rods fixed inside the vessel and are consequently difficult of access, and are
liable to corrosion and other deleterious effects from the action of the water,
and the steam.
My invention is designed to obviate these disadvantages.
I take a steam whistle of the well known dome shaped pattern, which I affix
to the boiler or other vessel in any convenient way. The bottom of this whistle
is fitted with an ordinary wing valve and seat, which has a spindle passing up
through the whistle, and projecting at the top.
Attached to the outside of the whistle is a joint in which is pivotted a lever
bearing on the top of the spindle, and carrying at its other end a movable weight,
exactly as used in an ordinary safety valve, and which can be adjusted to any
required pressure.
When the steam pressure rises beyond the point required, the wing valve is
raised, allowing the steam to blow the whistle.
As the ordinary dome-shaped whistle requires steam at a considerable pressure
in order to blow it, I alter the pattern of this for low pressures.
Instead of the steam impinging on the knife edge of the dome, I take the
steam inside a closed tube, and in opposite sides, I cut two semi-elliptical aper-
tures, through which the steam blows to actuate the whistle.
At the top of the dome, I drill two small holes to enable the steam to escape,
so as not to clog the whistle.
This makes the whistle very sensitive, and enables the apparatus to be used for
either air or steam at very low pressures.
Dated this 17th day of May. 1898.

page_text: the same is to be performed, to be particularly described and ascertained in and
by the following statement;--
The object of my invention is a whistle, blown by steam or air, to give warn-
ing when the pressure in a boiler or other vessel or pipes exceeds the desired
amount.
The devices in use for this purpose at the present time are actuated by floats, and
rods, fixed inside the vessel, and are consequently difficult of access, and are
liable to corrosion, and other deleterious effects from the action of the water
and the steam.
My invention is designed to obviate these disadvantages.
I take a steam whistle of the well known dome shaped or other pattern, which I
affix to the boiler or other vessel in any convenient way. The bottom of this
whistle is fitted with an ordinary wing valve and seat, which has a spindle passing
up through the whistle and projecting at the top.
Attached to the outside of the whistle is a joint in which is pivotted a lever
bearing on top of the spindle, and carrying at its other end, a movable weight
exactly as used in an ordinary safety valve, which can be adjusted to any required
pressure. When the steam pressure rises beyond the point required," the wing
valve is raised, allowing the steam to blow the whistle.
As the ordinary dome shaped whistle requires steam at considerable pressure
in order to blow it, I alter the pattern of this for low pressures.
Instead of the steam impinging on the knife-edge of the dome, I take the
steam inside a closed tube, and in opposite sides I cut two semi-elliptical aper-
tures through which the steam blows to actuate the whistle.
At the top of the dome I drill two small holes to enable the steam to escape
so as not to clog the whistle. This makes the whistle very sensitive, and enables
the apparatus to be used for either air or steam at very low pressures.
In the accompanying drawing, Figure 1 is a sectional view of the whistle;
Figure 2 is a section taken on line 1-2; Figure 3 is a view showing the shape
of the semi-elliptical apertures, or lips of the whistle, and Figure 4 shows an
alternative arrangement, a spiral spring being substituted for the lever and weight.
In Figure 1, A represents the bell, or tube of the whistle, made preferably of
gun-metal, which is attached to the base of the whistle B, by the threads, band
terminating in a hollow screwed end or nozzle, b, having in its centre, an inlet
or orifice, b, and which can be attached to a pipe, boiler, or other vessel as required.
In the base B, is a seating C, for the valve C¹ of any convenient type, prefer-
ably, the type known as a wing valve.
To this valve, C' is attached a spindle, C³, which is carried up the bell of the
whistle, and through a hole in the top A', to a point slightly above the top where
it impinges on the lever D, pivotted on the pin, D', and having towards its other
extremity the weight E, suspended in a convenient manner.
The pin D', is carried preferably in a suitable screwed eye F, attached to a
projecting lug, G, affixed to the bell of whistle A. On the opposite side of the
whistle, is a similar lug G', which carries a guide H, in which the lever 1 works.
In the bell of whistle A, at a suitable height, is attached a baffle plate, or
diaphragm, J cut away at opposite sides to form the passages J', through which
the steam passes to impinge on the edges of the semi-elliptical apertures, or lips K,
which are of the form shown in Figure 3.
In the top of the whistle are small holes, A2, to allow surplus steam to escape.
The action of my pressure whistle is as follows:-
When the whistle is attached to any pipe, boiler, or vessel containing air, or
steam, and communicating therewith through the orifice, or inlet, 68 of the nozzle 6'
pressure will be exerted on the valve, C, in the direction shown by the arrow.
The lever D, and weight E, adjusted to the required pressure, bearing on the
upper end of the rod C³, will hold the valve C¹, in its seat until the pressure
rises to the required point, when the air, or steam will raise the valve, and rushing

page_text: through the passages, J', will impinge on the edges of the semi-elliptical aper-
tures K, and cause the whistle to sound.
It is obvious that this arrangement may be modified in various ways. One of
these show in Figure 4. I do away with the lever and weight, and substitute
on the top of the whistle, a light frame or cage, L. On the rod C, of the valve, C',
I fix a collar, C, which bears against a spiral spring, M, contained in the cage L.
At the top of cage L, in a boss, L', is placed an adjusting screw, N, in any con-
venient manner to regulate the pressure on the valve.
When the steam is admitted to the whistle as before described, it is obvious that
the spring will act in precisely the same way as the weight and lever in controlling
the valve, and regulating the pressure at which the whistle will blow.
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. In whistles blown by air or steam, the use of a valve, in combination with
a lever and weight, or spring to regulate the pressure at which the whistle will
sound, as herein fully described and illustrated.
2. In whistles made in accordance with the foregoing description, and for the
purpose set forth, the use of semi-elliptical apertures, or lips as described, and
shown in Figure 3 on the accompanying drawing.