IMPROVEMENTS IN STEAM AND OTHER PRESSURE GAUGES to be as follows:--
Year: 1884

page_text: I, JAMES BURDEN of Conybere Street Birmingham, in the County of Warwick,
Manufacturer, do hereby declare the nature of said invention for "IMPROVEMENTS
IN STEAM AND OTHER PRESSURE GAUGES to be as follows:--
"
My invention has reference to gauges for indicating the pressure of steam and
other fluids and liquids, and consists of the arrangement and combination herein-
after described whereby the pressure exerted by the action of steam, fluid or liquid
is indicated upon a graduated dial by a traversing finger moved or acted upon by
the inflection or dilation of the body which is in direct contact with the pressure
exerted by the said steam, fluid or liquid.
For convenience of description, I will describe my invention as applied to a
Bourdon gauge, which consists of a curved flat tube, the free end of which is con-
nected by a link to the short arm of a lever which carries a toothed quadrant,
gearing with a pinion on the axis of the indicating finger. The straightening out
or dilation of the tube imparts motion to the pinion carrying the indicating finger.
By my invention, I dispense with the use of the ordinary toothed quadrant and
pinion commonly employed.
In constructing a gauge according to my invention of the Bourdon type, the flat
tube in which steam enters is of nearly a complete circle, the fixed end of which is
connected with the usual steam passage, while its free end carries a link which is
connected to the short arm of a plain quadrant, the said quadrant turns upon an
axis supported by a bracket in the ordinary way. The indicating finger has fixed
upon its axis a grooved pulley or sheave through which motion is communicated
from the quadrant, to the indicating finger. The circumference of the arc of the
quadrant head is preferably struck from the centre upon which the quadrant lever
turns. Motion is communicated from the quadrant head to the pulley or grooved
roller on the axis of the indicating finger by a chain or band, one end of which is
attached to a fixed point on one side of the quadrant, and the other end is affixed t
the other side of the said quadrant, while the middle of the chain or band is wound
round the pulley or sheave; so that the chain or band which communicates motion
to the indicating finger, lies upon the circumference of the circle comprehended
between two radii, included by the arc or quadrant.
The action of the instrument or gauge is as follows; steam being admitted
into the curved flat tube, the pressure of which is indicated by the dilation or

page_text: straightening out of the said tube according to the pressure exerted within it. The
dilation of the tube described, draws or moves forward the link on its free end, and
so communicates motion to the short arm of the quadrant lever. The chain or band
lying on the periphery of the quadrant is payed out or'uncoiled from one to the
other side of the quadrant, and so communicates motion to the indicating finger
carried by the pulley around which the chain or band passes; in other words, the
degree with which the tube dilates, and contracts, by varying pressures, is trans-
mitted through a link attached to the short arm of a quadrant lever, which has a
chain or band stretched between its extreme points or radii, the middle of the said
chain or band passing around the circumference of a grooved pulley; so that, on the
change of position of the quadrant by inflection or otherwise, the chain or band
stretched over the periphery, and moving with the quadrant arm, rotates the pulley
. around which its middle is wound or coiled, and so by its change of position,
forward or backward, indicates the varying pressure by the graduations indicated
by the finger or pointer which traverses equally the divisions on the scale or dial.
The gauge is smooth in its action, sensitive in indicating, and the moving parts are
almost frictionless.
Instead of employing the quadrant of a circle, the same result may be obtained
bý stretching the chain for communicating motion around the periphery of a
complete circle. And where one chain or band only, is required for transmitting
the movement or inflection of the tube to the indicating finger axis, a weight is
hung and suspended by a cord, passing around the index finger axis for giving the
back movement; that is, the chain or band is affixed to the left hand end of the
quadrant, and the other end is coiled around and attached to the pulley; so that
on the motion of the quadrant from right to left, pulls and uncoils the chain from
the pulley, and so imparts motion to the indicating finger to which the said pulley
is attached. On the back movement of the quadrant, by the relaxation of pressure,
the slack of the chain or band and the index finger is brought back by the
uncoiling of the weighted cord around the finger axis.
The weight and cord described, effectually keeps the working parts of the instru-
ment to their bearings or work; thus counteracting any looseness of back lash that
may occur.
Although I have only described my invention as applied to a central hand
Bourdon gauge, yet my said invention is equally applicable to every description of
"gauge for determining-pressure.-

page_text: COMPLETE SPECIFICATION.
I JAMES BURDEN of Conybere Street Birmingham, in the County of Warwick
Manufacturer, do hereby declare the nature of said invention. for "IMPROVEMENTS
IN STEAM AND OTHER PRESSURE GAUGES," and in what manner the same is to be
performed, to be particularly described and ascertained in and by the following
statement:-
My invention has reference to gauges for indicating the pressure of steam and
other fluids and liquids, and consists of the arrangement and combination hereinafter
described whereby the pressure exerted by the action of steam, fluid or liquid is
indicated upon a graduated dial by a traversing finger moved or acted upon by the
inflection or dilation of the body which is in direct contact with the pressure
exerted by the said steam, fluid or liquid.
For convenience of description I will describe my invention as applied to a
Bourdon gauge, which consists of a curved flat tube, the free end of which is
connected by a link to the short arm of a lever which carries a toothed quadrant
gearing with a pinion on the axis of the indicating finger, the straightening out or
dilation of the tube imparts motion to the pinion carrying the indicating finger.
By my invention I dispense with the use of the ordinary toothed quadrant and
pinion commonly employed.
In constructing a gauge according to my invention of the Bourdon type, the flat
tube in which steam enters is of nearly a complete circle, the fixed end of which is
connected with the usual steam passage, while its free end carries a link which is
connected to the short arm of a plain quadrant, the said quadrant turns upon, an
axis supported by a bracket in the ordinary way. The indicating finger has fixed
upon its axis a grooved pulley or sheave or it may be a plain axis through which
motion is communicated from the quadrant to the indicating finger. The circum-:;
ference of the arc of the quadrant head is preferably struck from the centre upon
which the quadrant lever turns. Motion is communicated from the quadrant head
to the axis of the indicating finger by a chain or band, one end of which is attached
to a fixed point on one side of the quadrant, and the other end is affixed to the
finger axis, or to the other side of the said quadrant, so that the middle of the
chain or band of the last named arrangement is wound round the pulley or sheave,
which communicates motion to the indicating finger.
The action of the instrument or gauge is as follows, steam being admitted into
the curved flat tube, the pressure of which is indicated by the dilation or straightening
out of the said tube according to the pressure exerted within it. The dilation of
the tube described, draws or moves forward the link on its free end, and so
communicates motion to the short arm of the quadrant lever. The chain or band
lying on the periphery of the quadrant is paid out or uncoiled and so communicates
motion to the indicating finger carried by and around which the chain or band
passes, in other words the degree with which the tube dilates and contracts by
varying pressures is transmitted through a link attached to the short arm of a
quadrant lever which has a chain or band stretched over its quadrant end and
connected with the finger axis, so that on the change of position of the quadrant

page_text: by inflection or otherwise, the chain or band moving with the quadrant arm,
rotates the finger axis, and so by. its change of position, forward or backward
indicates the varying pressure by the graduations indicated by the finger or pointer
which traverses equally the divisions on the scale or dial.
The gauge is smooth in its action, sensitive in indicating, and the moving parts
are almost frictionless.
•
Instead of employing the quadrant of a circle, the same result may be obtained
by stretching the chain for communicating motion around the periphery of a
complete circle. And where one chain or band only, is required for transmitting
the movement or inflection of the tube to the indicating finger axis, a weight is
hung and suspended by a cord passing around the index finger axis for giving the
back movement; that is, the chain or band is affixed to the left hand end of the
quadrant and the other end is coiled around and attached to the pulley, so that on
the motion of the quadrant from right to left pulls and uncoils the chain from the
pulley and so imparts motion to the indicating finger, to which the said pulley is
attached. On the back movement of the quadrant, by the relaxation of pressure,
the slack of the chain or band and the index finger, is brought back.by the uncoiling
of the weighted cord around the finger axis. The weight and cord. described
effectually keeps the working parts of the instrument to their bearings or work,
thus counteracting any looseness or back lash that may occur.
Although I have only described my invention as applied to a central hand
Bourdon gauge, yet my said invention is equally applicable to every description of
gauge for determining pressure.
I will now proceed to describe with reference to the accompanying Drawing, the
manner in which my invention is to be performed.
་
Figure 1 represents a gauge constructed according to my invention of the Bourdon
type, in which a chain is used for communicating motion from the quadrant arm to
the finger axis the gauge being in its normal position, with the graduated dial and
outer casing or covering cap removed. Figure 2 represents the same with the tube
dilated or straightened out by pressure exerted within it. Figure 3 is a cross
vertical section of figure 1. Figure 4 is the quadrant arm and finger axis separately
on a larger scale. Figure 5 shows an arrangement whereby motion is communicated
to the finger axis by means of an endless chain or cord, which encircles the said
-finger-axis. Figure-6-is-the-said-arrangement-shown-in-its-normal-position.
The same letters of reference indicate the same parts in figures 1, 2, 3 and 4.
a is the body or casing of the gauge, and b is the curved flat pressure tube, by
the dilation or straightening out of which, the pressure of steam is indicated-The
free end of the said tube b is connected by a link 62 to the short arm-c of a lever c,
provided with a quadrant cross head c³. The said quadrant lever c turns upon
a fulcrum d supported by a hanging bracket d². The circuinference of the quadrant
head is struck from the centre d upon which the lever turns. e is the finger axis
carrying the finger f, the said axis is carried by a hanging bracket y and motion is
communicated to the said axis from the quadrant lever, by a chain or cord h, one
end of which is attached to the quadrant head c³ and the other end to the finger
axis; so that the chain or band which communicates motion through the quadrant
lever c, lies or is stretched upon the circumference of the circle of the quadrant
head, and passes a sufficient distance around the finger axis to move it through the
requisite distance. is a weight suspended at the end of a chain or cord coiled
around the finger-axis. This weight assists in the bringing back of the finger axis
on relaxation of pressure, or rather takes up the slack on the return of the finger
axis, so as to keep the working parts of the instrument to their bearings or work;
thus counteracting any looseness or back-lash that may occur. ; is a guide for
steadying the weight i and k is the cord or chain coiled around the finger axis.
The action of the gauge is as follows, steam being admitted into the curved flat
tube, the pressure is thereby indicated by the dilation or straightening out. The
dilation of the tube b draws or moves forward the link 62 at its free end, and so
communicates motion to the short-arm-e of the lever c, the chain lying on the

page_text: quadrant end c is paid from off and coiled around the finger axis, by the weight i
which takes up the slack of the chain and turns the finger to a position proper
for indicating the pressure of steam as represented in figures 2 and 4. On the
relaxation of steam pressure, the quadrant arm moves to its normal position as
represented in figure 1. The finger axis being brought into a position and the
weight i raised with its chain or cord coiled around the finger axis ready to rotate
it on the relaxation of the chain carried by the quadrant arm.
In figure 5 the chain his attached at two points ²² to the quadrant arm,
which forms an endless chain or cord, the middle of which passes around the axis
of the index finger, so that on the dilation of the tube b, the link at its free end,
actuates the quadrant arm c which pays out the chain lying on the periphery h² to
the other side of the quadrant, and so communicates motion to the indicating finger
carried by the pulley or axis around which the chain passes as represented in
figure 6, so that on the change of position of the quadrant, by inflection or
otherwise, the chain or cord stretched over its periphery rotates the finger axis or
pulley around which its middle is wound, and so by the change of its position.
forward or backward, indicates the varying pressure by the traversing of the finger
on the graduated dial of the gauge.
Gauges constructed with the movements herein before described, are smooth in
their action, sensitive in indicating and the acting parts move almost frictionless.
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-Constructing and arranging the parts of steam and other pressure gauges
herein before described and illustrated in figures 1, 2, 3 and 4 of the accompanying
Drawing, whereby the inflection or dilation of a body exérted upon by steain or
other pressure is made to communicate motion to the finger axis of the instrument
through the intervention of a chain or cord, one end of which is attached to the
quadrant arm of a lever and the other end to the finger axis, so that on pressure
being exerted, the quadrant arm changes its position and slackens the chain or cord
which is taken up by a suspended weight, the lowering of which rotates the finger
axis as described and set forth.
Secondly. The general arrangement or combination of the parts of pressure
gauges herein before described and set forth in figures 1, 2, 3 and 4 of the
accompanying Drawing,
Thirdly. The means of communicating motion to the finger axis of steam and
other pressure gauges, by the intervention of a chain or cord stretched over the
plain quadrant head of a lever, the terminal ends of the chain or cord being attached
at two fixed points, while the middle of the chain or cord is coiled around the
finger axis, and so communicates motion thereto on the to and fro movement of
the lever, as described and set forth in figures 5 and 6 of the accompanying
Drawings.
Fourthly. The use of a counterbalance weight with its cord or chain as
described and represented, for the keeping of the moving parts of gauges to their
bearings.