AN IMPROVED CONSTRUCTION OF GIFFARD INJECTOR
Year: 1865

page_text: LETTERS PATENT to Alfred Vincent Newton, of the Office for Patents,
66, Chancery Lane, in the County of Middlesex, Mechanical Draughts-
man, for the Invention of "AN IMPROVED CONSTRUCTION OF GIFFARD
INJECTOR." A communication from abroad by William Sellers, of
Philadelphia, in the State of Pennsylvania, United States of America.
-
Sealed the 16th June 1865, and dated the 12th April 1865.
PROVISIONAL SPECIFICATION left by the said Alfred Vincent Newton
at the Office of the Commissioners of Patents, with his Petition, on the
12th April 1865.
I, ALFRED VINCENT NEWTON, of the Office for Patents, 66, Chancery
Lane, in the County of Middlesex, Mechanical Draughtsman, do hereby
declare the nature of the said Invention for "AN IMPROVED CONSTRUCTION
OP GIPPARD INJECTOR," to be as follows:-
This Invention relates to an improvement in the Giffard injector, whereby
it is made self-regulating. In this instrument, as heretofore constructed, the
supply of water and steam has been regulated by means of screws, levers, or

page_text: other devices controlled by hand, so that whenever the tension or pressure of
the steam varies the attendant is obliged to re-adjust the supply of water in
order that the instrument may work to the best advantage, and whenever the
pressure falls below the point to which the instrument has been adjusted a
re-adjustment becomes necessary to prevent a waste of water at the overflow.
The present Invention consists in using the overflow to control the admission
of the water or steam, or both, to the injector, so that the pressure inside tho
chamber, caused by an overflowing jet, shall diminish the supply of water, or
increase the supply of steam, or it may effect both whilst the water which has
escaped at the overflow to produce this effect being retained in contact with
the jet, will be drawn in again whenever the supply of water is too small, or
the supply of steam too great, and thus produce a partial vacuum in the over-
flow chamber, reverse the previous operation and re-adjust the instrument to
the new conditions without any waste at the point of overflow.
The following are the means employed for utilizing the power
mentioned.
The outer shell or case of the injector is made in two parts united by a nut
tapped with right and left handed screw thread. The one part is provided with
two nozzles for the admission respectively of steam and water, the two being
separated by a division plate. In the centre of this plate is a nozzle for the
steam jet, the amount of steam that can be discharged from this nozzle being
regulated by a tapered plug which may be operated by a screw, lever, or other
convenient device. The interior of the case beyond the water nozzle is bored
out for a short distance and fitted with a cylindrical brass lining to receive a
hollow piston which forms the upper or receiving end of a receiving and
discharging pipe, whose axis coincides with that of the steam jet nozzle. The
pipe is so arranged as to be capable of moving to or from the steam jet nozzle
so as to enlarge or contract the annular space between it and the receiving
pipe, thereby governing the amount of water which can be admitted to the
action of the steam escaping from the steam jet nozzle. The pipe is gradually
contracted through about half its length, when it commences to enlarge, and
gradually increases until it discharges into a perforated chamber, and subsc-
quently into the second portion of the case which surrounds it. This part of
the outer shell or case is provided with a nozzle from which the water discharged
from the perforated chamber can be conducted into the boiler. There must
be provided a waste cock or valve to enable the water escaping from the
perforated chamber to be discharged freely into the atmosphere for the purpose
of establishing the jet when first started; so soon as this is accomplished,
this waste must be stopped, and will be of no further use so long
as the jet is in motion. Between this and the boiler to be fed with water

page_text: is a check valve to prevent the return of the water when the instrument is:
stopped. The second part of the shell or case is closed at one end by 'a plate
or head, and the other end is closed by a screw cap. Between the cap and
the head is a second head forming with the cap a small chamber, the use of
which will be presently described. Both these heads are provided with stuffing
boxes which allow the feed pipe and an extension of the perforated chamber
to play freely longitudinally without leakage. In the lower side of the second
portion of the case a channel is formed which communicates between the first
portion of the case and the small chamber above mentioned. Through the
axis of the receiving and discharging pipe, and a short distance above its smallest
diameter, that is, toward its receiving end, a small hole is made to allow an
escape of water when a too abundant supply is admitted at the receiving end.
When this occurs the superabundant water will find its way to the small
chamber, and accumulate there until it exerts a pressure upon the. nd of the
pipe and piston, and causes the whole to move toward the steam discharge
nozzle, thus diminishing the water supply until the quantity admitted is in
exact proportion to the supply of steam, the relative positions of these nozzles.
will then remain the same, until some change takes place in the pressure of
the water supply, or the tension of the steam.
SPECIFICATION in pursuance of the conditions of the Letters Patent, filed
by the said Alfred Vincent Newton in the Great Seal Patent Office on
the 19th October 1865.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, ALFRED
VINCENT NEWTON, of the Office for Patents, 66, Chancery Lane, in the
County of Middlesex, Mechanical Draughtsman, send greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her Letters
Patent, bearing date the Twelfth day of April, in the year of our Lord
One thousand eight hundred and sixty-five, in the twenty-eighth year of
Her reign, did, for Herself, Her heirs and successors, give and grant unto
me, the said Alfred Vincent Newton, Her special licence that I, the said
Alfred Vincent Newton, my executors, administrators, and assigns, or such
others as I, the said Alfred Vincent Newton, my executors, administrators,
and assigns, should at any time agree with, and no others, from time to time
and at all times thereafter during the term therein expressed, should and
lawfully might make, use, exercise, and vend, within the United Kingdom

page_text: of Great Britain and Ireland, the Channel Islands, and Isle of Man, an
Invention for "AN IMPROVED CONSTRUCTION OF GIFFARD INJECTOR," being a
communication from William Sellers, of Philadelphia, in the State of
Pennsylvania, United States of America, upon the condition (amongst
others), that I, tho said Alfred Vincent Newton, my executors or adminis-
trators, by an instrument in writing under my, or their, or one of their hands
and seals, should particularly describe and ascertain the nature of the said
Invention, and in what manner the same was to be performed, and cause
the same to be filed in the Great Seal Patent Office within six calendar
months next and immediately after the date of the said Letters Patent.
NOW KNOW YE, that I, the said Alfred Vincent Newton, do hereby
declare the nature of the said Invention, and in what manner the same
is to be performed, to be particularly described and ascertained in and by
the following statement, reference being had to the Drawing hereunto annexed
and to the letters and figures marked thereon (that is to say):-
:-
This Invention relates to an improvement upon that well known instrument
the Giffard injector, the object being to make it self-regulating. In this
instrument as heretofore constructed, the supply of water and steam has been
regulated by means of screws, levers, or other devices controlled by hand so
that whenever the tension or pressure of the steam varies, the attendant is
obliged to readjust the supply of water in order that the instrument may
work to the best advantage, and whenever the pressure falls below the point
to which the instrument has been adjusted, a readjustment becomes necessary
to prevent a waste of water at the overflow.
locomotive and others, having a small water and steam capacity compared to
their beating surface, and where the demand for steam is very irregular, the
variations of the steam pressure are considerable and very frequent, and the
amount of attention required for regulating the injector becomes a serious
inconvenience.
In many boilers, such as the
The object of my Invention is to make this regulation self-acting and
dependent upon the amount of steam or water admitted to the instrument, and
to utilize a power until now wasted at the overflow. The overflow, as here-
tofore used has been for the purpose of permitting the escape of the water
before it has attained sufficient velocity to enable it to enter the boiler when
the jet is first started and also to permit (when the jet is in motion) the
superabundant water or steam to escape without stopping the operation of the
instrument. It has long been known that the overflow was not necessary
after the jet was fairly established, and the steam and water supply properly
regulated, but it has not been known heretofore that when the jet is stopped

page_text: by a superabundant supply of water, no provision being made for waste, an
amount of lateral pressure may be obtained at the point of overflow nearly
equal to that in the boiler. It has also been long known that the fluid jet in
passing the point of overflow will, when not in excess, carry along with it into
the boiler any fluid that may be in contact with it, so that if the overflow
chamber should be closed up a moderate vacuum can be produced there by
this action of the jet.
The present Invention consists in using the overflow water to control the
admission of the water or steam or both to the injector, so that the pressure
inside the chamber, caused by an overflowing jet, shall diminish the supply of
water or increase the supply of steam, or it may effect both, whilst the water
which has escaped at the point of overflow to produce this effect, being retained
in contact with the jet will be drawn in again whenever the supply of water is
too small or the supply of steam too great, and thus produce a partial vacuum
in the overflow chamber, reverse the previous operation, and readjust the
instrument to the new conditions without any waste at the point of overflow.
The means employed for utilizing the power mentioned will be more fully
understood from the following description:-The outer shell or case of the
injector is made in two parts A and B, united by a nut C, having a right-hand
screw thread in one side, and a left-hand one in the other, with corresponding
threads on the parts A and B. The part A is provided with two nozzles D
and E, the nozzle D for the admission of steam, and E for the admission of
the water, the two being separated by the plate F. In the centre of the
plate Fa nozzle G is provided for the steam jet, the amount of steam that can
be discharged from this nozzle being regulated by the tapered plug H, which
may be operated by a screw, lever, or other convenient device.
The interior of the case A beyond the water nozzle E is bored out for a
short distance and fitted with a cylindrical brass lining a, a, which is turned
out to receive the packing b, b, in the piston I; this piston forms the upper or
receiving end of the receiving and discharging pipe J, J, which has its axis
coinciding with that of the steam discharge nozzle G. The pipe J, J, is so
arranged as to be capable of moving to or from the nozzle G, so as to enlarge
or contract the annular space between the exterior of G and the interior of the
receiving pipe, thereby governing the amount of water which can be admitted
to the action of the steam escaping from the nozzle G. The pipe J, J, is
gradually contracted through about half its length, when it commences to
enlarge, and gradually increases until it discharges into the perforated
chamber K, and subsequently into the space between it and the case B which
surrounds it. The part B of the outer shell or case is provided with a nozzle L,

page_text: from which the water discharged from the chamber K can be conducted into
the boiler. There must be provided a waste cock or valve to enable the water
escaping from the perforated chamber K to be discharged freely into the
atmosphere for the purpose of establishing the jet when first started; so soon
as this is accomplished this waste cock must be closed, and will be of no
further use while the jet is in action; it may be placed in any convenient
position, and is shewn upon the pipe leading to the boiler; between this and
the boiler a check valve must be employed to prevent the return of the water
when the instrument is stopped. The shell or case B is closed at one end and
by a plate or head M, which projects into the case A, in which it is accurately
fitted for the purpose of maintaining the axis of the steam nozzle G in the
line of the axis of the receiving and discharging pipe J, J. The other end of
the case B is closed by a screw cap N, accurately fitted, so as to prevent any
leakage of air or water. Between the cap N and the head M is a second
head O, forming a chamber P between them, the use of which will be herein-
after described. Both these heads M and O are provided with stuffing boxes,
which allow the pipe J, J, and the extension J' of the chamber K to play
freely longitudinally without permitting the escape of any water discharged
from the chamber K. Between the heads M and O, and opposite the nozzle L,
is a projection R, cast with the outer case B. Through this projection a
small hole c, c, is drilled to form a communication between the upper chamber
in the case A and the chamber P in the case B, and it is important that this
shall be perfectly sound so as to prevent any escape of water into it that bas
once passed from the perforated chamber K. Through the axis of the
receiving and discharging pipe J, J, and a short distance above its smallest
diameter, that is, toward its receiving end, a small hole d, d, is made for the
purpose of allowing an escape of water when a too abundant supply is
admitted at the receiving end, and this hole I call the overflow. The
operation of the instrument is as follows, viz. :-The waste cock between the
instrument and boiler must first be opened, then admit the supply of water,
allowing it to flow through this waste, let on the steam, when an immediate
increase will take place in the volume of water escaping at the waste, shewing
that the jet has been established. The waste cock may now be closed, and
the water will flow into the boiler, but in case there should be too much
water admitted at the receiving end of the pipe J, J, the superabundance will
escape through the holes d, d, into the chamber in the case A, thence through
the holes c, c, into the chamber P in the case B, and will continue so to do
until both chambers are full, when it will exert a pressure upon the end J¹ of
the pipe J, J, and piston I, causing the whole to move forward the steam

page_text: discharge nozzle G, thus diminishing the water supply until the quantity
admitted is in exact proportion to the supply of steam. The relative positions
of these nozzles will then remain the same until some change takes place in
the pressure of the water supply or the pressure of the steam. Supposing
'now the pressure of the steam in the boiler should increase, or that the tapered
plug H should be drawn back from the opening in the nozzle G, so that a
larger quantity of steam should be discharged, the increased velocity of the jet
will carry along with it into the boiler some of the water which had pre-
viously escaped through the openings d, d, causing a partial vacuum under the
piston I; the pressure of the water will then cause it to recede from the nozzle G,
thus admitting more water until the equilibrium is again established. The
Jower chamber P is not necessary to the operation of the instrument, but by
its use the amount of surface exposed to pressure from the overflow is increased,
thereby increasing the sensitiveness of the adjustment, and the escape of any
waste (in case the packing in the head O should leak) is prevented. From
the foregoing it is evident that the instrument, when constructed as described,
requires only the adjustment of the steam supply, the regulation of the water
being controlled by the quantity of steam admitted. To make the instrument
entirely self-adjusting and capable of maintaining the water in the boiler at
a uniform height requires only that the position of the plug which regulates
the steam escaping from the steam discharge nozzle should be regulated by the
height of the water in the boiler. Almost any of the numerous devices in use
which govern the water supply by the height of the water in the boiler would
answer the purpose, and could be readily applied; and to determine whether
the jet is in motion a light safety valve may be attached to either the upper
or lower overflow chamber, and weighted to an extent sufficient to produce a
pressure in this chamber capable of moving the receiving and discharging pipe,
then with a check valve in the water supply pipe which will permit the water
to flow to the instrument, the failure to work would instantly be notified by
tbe escape of steam and water at this safety valve. The water supply may be
regulated by various other methods than by the adjustment of the receiving
pipe, and this pipe may be adjusted by the weight of the water escaping at the
overflow without regard to its pressure; the supply of steam may in like
manner be controlled by the instrument itself, so as to correspond with the
quantity of water admitted, or both the steam and water supply may be
controlled by this means.
Having now set forth the nature of the Invention of an improved con-
struction of Giffard injector, and explained the manner of carrying the same
into effect, I wish it to be understood that under the above in part recited

page_text: Letters Patent I claim the means above described for making the Giffard
injector, self-regulating.
In witness whereof, I, the said Alfred Vincent Newton, have hereunto
set my hand and seal, the Tenth day of October, in the year of our Lord
One thousand eight hundred and sixty-five.
A. V. NEWTON. (L.S.)