IMPROVEMENTS IN THE GIFFARD INJECTOR
Year: 1866

page_text: LETTERS PATENT to John Robinson, of the Atlas Works, in the City of
Manchester, and County of Lancaster, Engineer, for the Invention of
"IMPROVEMENTS IN THE GIFFARD INJECTOR."-A communication from
abroad by William Sellers, of Philadelphia, in the State of Penn-
sylvania, United States of America.
Sealed the 29th January 1867, and dated the 1st August 1866.
PROVISIONAL SPECIFICATION left by the said John Robinson at the
Office of the Commissioners of Patents, with his Petition, on the 1st
August 1866.
I, JOHN ROBINSON, of the Atlas Works, in the City of Manchester,
and County of Lancaster, Engineer, do hereby declare the nature of the
said Invention for "IMPROVEMENTS IN THE GIFFARD INJECTOR," communicated
to me from abroad by William Sellers, of Philadelphia, in the State of
Pennsylvania and United States of America, to be as follows:-
One part of the improvements to be herein-after described are only appli-
cable to the self-adjusting Giffard injector, for which Letters Patent were

page_text: obtained for Great Britain by Alfred Vincent Newton, Number 1051, and
dated the Twelfth day of April, in the year of our Lord One thousand eight
hundred and sixty-five, the other part of the improvements are applicable to
other Giffard injectors as well as to self-adjusting injectors.
In the instrument described in the Specification of the said Patent granted
to the said Alfred Vincent Newton it will be observed that the fluid jet is
discharged laterally from the pipe (; and ¹) so as to permit of an arrange-
ment which will prevent the boiler pressure from producing any movement of
this pipe to accomplish this object the pipe (; and 3) is extended beyond
the point of discharge so as to pass through another stuffing box of the same
size as the one above the point of discharge, thereby preventing any pressure
in the direction of the axis of the pipe (j). The object of the present
improvements is to simplify the construction of the self-adjusting injector
and also to make it capable of lifting its supply water, to increase the range
of injectors by decreasing their minimum delivery and to increase their
capacity for lifting the supply water from a lower level.
The nature of this Invention consists in making the external diameter of
the divergent tube or pipe which delivers the water from the self-adjusting
injector to the boiler of such size that the boiler pressure can exert but a very
slight influence upon the end exposed to it, the internal shape of this pipe
conforming as near as possible to that which the jet would assume when
forced into a fluid at rest, in which case no lateral strain would be exerted
upon the pipe, and the only pressure that could produce à longitudinal move-
ment would be that exerted upon the edge where the parallel outside meets
the divergent inside, and it also consists in limiting the movement of the self-
adjusting piston so as to obtain an effective vacuum, and in arranging the
steam discharging nozzle in any injector so that it may be elongated at the
same time that the 'discharge opening is being contracted.
These improvements will be more fully understood from the following
description of the apparatus:-The outer case or shell is made in two parts
which I shall name the upper and lower parts, united by a screw thread.
The upper part of the case or shell is provided with two branches, one to
admit steam and the other "to admit water, the two being separated by a
partition plate; in the centre of the partition plate a nozzle is provided for
the steam'jet, the amount of steam that can be discharged' being regulated by
a tapering plug, which may be operated by a screw, lever, or other convenient
"device. The interior of the lower part of the case or shell from the end
where it is joined to the upper part of the case is bored out for a short distance

page_text: and fitted with a cylindrical brass lining which is turned to receive the packing
of a piston which plays freely logitudinally therein; this piston forms the
upper or receiving, end of a converging pipe which is denominated the
combining tube, and this tube is united at its smaller end with a divergent
tube which is called the discharging tube, the axis of both tubes being in the
same line and in the line of the axis of the steam nozzle; the exterior of the
discharging tube is cylindrical, and it works in a brass-bushing screwed in a
partition in the lower part of the case or shell; this bushing must be of
sufficient length to prevent the escape of water in any important quantity
when the discharging tube is fitted so as to play freely through it. The
combining and discharging tubes must have sufficient movement longitudinally
to admit the maximum amount of water required between the exterior of the
steam nozzle and the interior of the combining tube; and to enable the
instrument to lift water from a lower level there must be a stop provided
which will prevent the combining tube from moving so far towards the steam
nozzle as to close the opening for water entirely; in this case the piston will
strike a small flange in the upper part of the case. before the surfaces
referred to can come in contact. This injector is provided with a starting
cock and check valve, as in the self-adjusting injector described in the
Specification of the aforesaid Patent granted to Alfred Vincent Newton. It
is well known that the form of the nozzles in the Giffard injector, although
well arranged for forcing water are not so well adapted to produce a vacuum
for the purpose of lifting the supply to the instrument; to remedy this defect
the plug or cone spindle is made much longer than is customary with the
ordinary injector, and a hole is drilled in its axis from its smaller end far
enough to communicate by means of a cross hole with the steam space in the
steam nozzle after the plug or cone spindle has closed the taper end of the
nozzle. The size of the hole in the axis of the plug or cone spindle should be
about one-half that of the smallest end of the divergent tube if intended to
lift only; but to obtain the smallest possible minimum delivery of. water it
will be necessary to make the hole somewhat larger, in which case a moveable
plug must be provided passing down the axis of-the first-named plug or cone
spindle to diminish the quantity of steam when it is desired to lift the supply
of water

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent, filed
by the said John Robinson in the Great Seal Patent Office on the
31st January 1867.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, JOHN
ROBINSON, of the Atlas Works, in the City of Manchester, and County of
Lancaster, Engineer, send greeting.
.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her Letters
Patent, bearing date the First day of August, in the year of our Lord One
thousand eight hundred and sixty-six, in the thirtieth year of Her reign,
did, for Herself, Her heirs and successors, give and grant unto me, the said
John Robinson, Her special license that I, the said John Robinson, my
executors, administrators, and assigns, or such others as I, the said John
Robinson, 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 of Great Britain and Ireland, the
Channel Islands, and Isle of Man, an Invention for "IMPROVEMENTS IN
THE GIFFARD INJECTOR," a communication from William Sellers, of Philadelphia,
in the State of Pennsylvania, United States of America, upon the condition
(amongst others) that I, the said John Robinson, by an instrument in writing
under my hand and seal, 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 John Rohinson, do hereby declare the
nature of my said Invention, and in what manner the same is to be per-
formed, to be particularly described and ascertained in and by the following
statement (that is to say) :-
One portion of the improvements to be herein-after described is only appli-
cable to the self-adjusting Giffard injector for which Letters Patent were
obtained for Great Britain by Alfred Vincent Newton, Number 1051, and
dated the Twelfth day of April, in the year of our Lord One thousand eight
hundred and sixty-five; the other portion of the improvements is applicable
to other Giffard injectors as well as to self-adjusting injectors, but the whole

page_text: of the improvements will be described as applied to a self-adjusting injector,
and illustrated by the Figure upon the accompanying Drawing, representing
a longitudinal section of the improved injector.
In the instrument described in the Specification of the said Patent granted
to the said Alfred Vincent Newton it will be observed that the fluid jet is
discharged laterally from the pipe (J and J¹) so as to permit an arrangement
which will prevent the boiler pressure from producing any movement of this
pipe. To accomplish this object the the pipe (J and J¹) is extended beyond the
point of discharge so as to pass through another stuffing box of the same size
as the one above, the point of discharge thereby preventing any pressure in
the direction of the axis of the pipe (J and J¹). The object of the present
improvements is to simplify the construction of the self-adjusting injector and
also to make it capable of lifting its supply water, to increase the range of
injectors by decreasing their minimum delivery, and to increase their capacity
for lifting the supply water from a lower level.
The nature of this Invention consists in making the external diameter of
the divergent tube or pipe (K) which delivers the water from the self-adjusting
injector to the boiler of such size that the boiler pressure can exert but a very
slight influence upon the end exposed to it, the internal shape of this pipe
conforming as near as possible to that which the jet would assume when
forced into a fluid at rest, in which case no lateral strain would be exerted
upon the pipe, and the only pressure that could produce a longitudinal move-
ment would be that exerted upon the edge where the parallel outside meets
the divergent inside, and it also consists in limiting the movement of the self-
adjusting piston so as to obtain an effective vacuum, and in arranging the
steam discharging nozzle in any injector so that it may be enlongated at the
same time that the discharge opening is being contracted.
These improvements will be more fully understood from the following
description of the apparatus:-The outer shell or case of the injector is made
in two parts, which I shall name the upper and lower parts, united by a screw
thread at C. The upper part of the case or shell (A) is provided with two
branches, one (D) to admit steam, and the other (E) to admit water, the two
being separated by a partition plate (F). In the centre of the partition
plate (F) a nozzle (G) is provided for the steam jet, the amount of steam
that can be discharged from the nozzle being regulated by a tapering plug (H)
which may be operated by a screw, lever, or other convenient device. The
interior of the lower part (B) of the case or shell from the end where it is
joined to the upper part (A) of the case is bored out for a short distance and

page_text: fitted with a cylindrical brass lining (a), which is turned to receive the
packing (6) of a piston (1), which plays freely longitudinally therein; this
piston forms the upper or receiving end of a converging pipe (J), which is
denominated the combining tube, and this tube is united at its smaller end
with a divergent tube (K), which is called the discharging tube, the axis of
both tubes being in the same line and in the line of the axis of the steam
nozzle (G); the exterior of the discharging tube (K) is cylindrical, and it
works in a brass bushing (L) screwed in a partition (1) in the lower part of
the case or shell (B); this bushing must be of sufficient length to prevent
the escape of water in any important quantity when the discharging tube (K)
is fitted so as to play freely through it. The combining and discharging
tubes. (J and K) must have sufficient movement longitudinally to admit the
maximum amount of water required between the exterior of the steam
nozzle (G) and the interior of the combining tube (J); and to enable the
instrument to lift water from a lower level there must be a stop provided
which will prevent the combining tube (J) from moving so far towards the
steam nozzle (G) as to close the opening for water entirely; in this case the
piston (1) will strike a small flange (d) in the upper part of the case before
the surfaces referred to can come in contact; this injector is provided with a
waste starting cock (M) and check valve (N), as in the self-adjusting injector
described in the Specification of the aforesaid Patent granted to Alfred
Vincent Newton. It is well known that the form of the nozzles in the
Giffard injector, although well arranged for forcing water, are not so well
adapted to produce a vacuum for the purpose of lifting the supply to the
instrument; to remedy this defect the plug or cone spindle (H) is made
much longer than is customary with the ordinary injector, and a hole (c) is
drilled in its axis from its smaller end far enough to communicate by means
of a cross hole (d) with the steam space in the steam nozzle (G), after the
plug or cone spindle (H) has closed the taper end of the nozzle (G). The
size of the hole in the axis of the plug or cone spindle should be about one
half that of the smallest end of the divergent tube if intended to lift only, but
to obtain the smallest possible minimum delivery of water it will be necessary
to make the hole somewhat larger, in which case a moveable plug (e) must
be provided, passing down the axis of the first-named plug or cone spindle (H)
to diminish the quantity of steam when it is desired to lift the supply
.water..
Having now particularly described the nature of the Invention com-
municated to me, and the manner in which the same is to be carried into

page_text: effect, I wish it to be understood that I claim as secured to me by the said
Letters Patent,-
Firstly, the discharging tube (K) in the self-adjusting injector when formed
substantially as described for the purpose specified.
Secondly, the flange (d) or its equivalent in the self-adjusting injector for
the purpose specified.
Thirdly, the hole (c) in the plug regulating the discharge of the steam in
the Giffard injector for the purpose specified.
In witness whereof, I, the said John Robinson, have hereunto set my
band and seal, this Twenty-second day of January, in the year of our
Lord One thousand eight hundred and sixty-seven.
JOHN ROBINSON. (L.S.)