1. The claims of letters patent No. 104,271, granted to Theodore
Clough, June 14, 1870, for an "improvement in gas burners,"
infra, p.
106 U. S. 168,
are valid, and they are infringed by a burner constructed in
accordance with the description contained in letters patent No.
105,768, granted to John F. Barker, July 26, 1870, for an
"improvement in gas burners."
2. A burner set up as anticipating Clough's invention, if used
now in a way in which it was never designed to be used and was not
shown to have ever been used before his invention, might be made to
furnish a supplementary supply of gas. It was not, however,
designed for the same purpose as his burner, and no person looking
at it or using it would understand that it was to be used in the
way that his was used, and it was not shown to have been really
used and operated in that way.
Held that it does not
amount to his invention.
3. The combination of the first claim of Clough's is new, and
he, having first applied a valve regulation of any kind thereto, is
entitled to hold as infringements of the second claim all valve
regulations applied to such a combination which perform the same
office in substantially the same way as, and were known equivalents
for, his form of valve regulation.
The facts are stated in the opinion of the Court.
Page 106 U. S. 167
MR. JUSTICE BLATCHFORD delivered the opinion of the Court.
This suit was brought by the appellant against the appellees to
recover for the infringement of letters patent granted to the
appellant July 14, 1870, for an "improvement in gas burners." The
circuit court dismissed the bill. The specification of the patent
says:
"My invention relates more particularly to the burners for
burning illuminating gas made by saturating air with vapors of
gasoline, commonly called air gas. It has been found that common
batwing or fishtail burners are not adapted to burning this gas as
ordinarily made owing to the variable density of the gas coming
from the generating apparatus. The object of my improvement is to
adapt the slitted or batwing burner to the burning of air gas. Said
improvements consist first in perforating the base of the burner
tube with small holes or passages for gas to escape at the base of
the burner, and surrounding the burner with a tube open at the top
but closed at the bottom and united to the burner below the
perforations in the burner tube. It is more convenient to screw the
tube to the burner, but it may be attached in any suitable manner.
Second, in regulating the escape of the gas from the perforations
at the base of the burner by a sliding tubular valve or cut-off,
introduced into the burner tube at the base and extending upward
within it, the position of the tubular valve being regulated by a
screw. These improvements, by furnishing a regulated supply of gas
outside of the burner, but directed to the tip of the burner by the
surrounding tube, give steadiness and increased illuminating power
to the flame of the batwing burner and make it a desirable burner
for burning air gas. The drawings represent a batwing burner as
improved by me. Figure 1 represents an elevation of my improved
burner attached to a short piece of gas pipe. Figure 2, a view
showing the surrounding tube in section and the burner therein.
Figure 3, a vertical section through the burner and tube. Figure 4,
a transverse section through the base of the burner tube. Letter
a represents the burner tip;
b the burner tube;
c perforations at the base of the burner tube;
d
the surrounding tube screwed to the base of
Page 106 U. S. 168
the burner tube;
e the tubular valve extending up in
the burner tube, and operated by an annular screw
f
attached to the lower end. Said annular screw, besides having a
screw to work in the base of the burner, has an internal screw by
which it and the burner are attached to the gas pipe, as clearly
shown in Fig. 3 and the other drawings, the gas way being through
the annular screw and tubular valve to the burner. As the burner is
connected to the gas pipe
g by means of the annular screw,
the adjustment of the gas escaping through the perforations of the
burner tube is easily made by turning the burner upon the annular
screw. I claim as my invention and improvement in air gas burners,
the batwing burner, perforated at the base, in combination with the
surrounding tube, substantially as described. Also, in combination
with the batwing burner, perforated at the base, and surrounding
tube, the tubular valve for regulating the supply of external gas
to the burner, substantially as described."
The defendants in their answer set up that they have not
infringed the patent and that it is void for want of novelty. At
the request of both parties, a trial at law was had in the court
below of two questions: first, whether or not the complainant is
the first and original inventor of the improvement in gas burners
for which the first above named patent has been granted to him;
second, whether or not the gas burners manufactured by the
defendants are substantially identical with those described in the
complainant's patent and schedule thereto annexed in their
construction and mode of operation.
The issues were tried before the court and a jury, and the jury
answered both of the questions in the affirmative. Afterwards, on a
case made, the defendants moved, before the judge who tried the
issues, for a new trial on the ground that the verdict was against
the weight of the evidence. He denied the motion in a written
opinion in which he stated that the weight of the evidence on the
question of infringement was not such as to justify him in granting
a new trial and that he was satisfied with the conclusion of the
jury on the question of priority. He afterwards signed and filed a
certificate that in his opinion the verdict on both questions was
sustained by the evidence given.
The burners made by the defendants were made in accordance with
the description of the first form of burner described
Page 106 U. S. 169
in the specification of letters patent granted to John F.
Barker, one of the defendants, July 26, 1870, for an "improvement
in gas burners." The drawings of that patent consist of ten
figures, which are thus referred to in the specification:
"Figure 1 is a side view of one modification of my invention;
Figure 2 is a side view of the shell; Figure 3 is a side view of
the burner; Figure 4 is a vertical longitudinal section of the
shell through line A B of Figure 2; Figure 5 is a vertical
longitudinal section of the burner through line C D of Figure 3;
Figure 6 is a side view of another modification of my invention;
Figure 7 is a side view of the shell; Figure 8 is a side view of
the burner; Figure 9 is a vertical longitudinal section of the
shell through line E F of Figure 7, and Figure 10 is a vertical
section through line G H of Figure 8."
The specification goes on to say:
"My invention relates to a device for regulating the flow of
carbureted air or gas from the burner to its point of combustion,
and it consists of a burner having a screw thread made upon its
lower part upon which is fitted, to turn freely thereon, a shell or
tube, also having a screw thread upon its interior lower part, and
the bore of said tube or shell is somewhat larger in diameter than
the diameter of the upper part of the burner upon which it turns. A
series of perforations is made in the lower part of the burner, so
that when the burner is made or set for the combustion of
carbureted air or gas of any certain quality, the flame may be
increased or diminished by turning the shell either up or down, as
the case may be, the shell, in its movements up or down, either
closing or opening the holes or perforations, and letting out or
stopping the flow of the gas through the said holes as it is moved
up or down. In the use of carbureted air for illuminating purposes,
it is almost always the case that when the gasoline is first placed
within the generator, it gives off a much greater amount of vapor,
and the air, in passing through the generator, absorbs a greater
amount of the carbon, and consequently becomes more thoroughly
charged with, and is much richer in the illuminating qualities of
the gasoline than when the generator has been charged for a greater
length of time, and as a result, the carbureted air is sometimes
too rich to make a desirable light, with the same amount passing
out of the burner, and at other times, as when the generator has
been charged a longer time, the carbureted air flowing through the
burner is deficient in illuminating power, and the light or flame
produced is
Page 106 U. S. 170
not uniform in its power or steadiness, and is sometimes liable
to produce a smell or smoke when too rich in carbon. My invention
is designed to obviate all difficulty in this respect, as the
burner is set or made to let out at the tip the minimum quantity of
gas that will produce a good flame, and as the gasoline remains
longer in the generator and becomes weaker in its illuminating
qualities, the outer tube or shell may be turned so as to let out
more gas and increase the flame without liability to smoke. That
others skilled in the art may be enabled to make and use my
invention, I will now proceed to describe its construction and mode
of operation:"
"In the drawing, L represents the main part of the burner, which
is made similar to the common burner, except that the lower part
has a screw thread made upon the outside and inside. Figs. 1, 2, 3,
4, and 5 represent one modification in which L is the burner,
having the usual screw thread made upon the lower interior part by
which to secure it to the pipe. At
a' is a conical
shoulder or seat upon the exterior, shown in Figs. 3 and 5, and a
screwthread
d, made upon the exterior of the lower end,
and the small holes
c are made either at the seat
a' or just below it. I is a shell or tube, the inside
diameter of its upper part being somewhat greater than the outside
diameter of the part L, and upon the interior of the tube at
a is a conical shaped seat made to fit upon the exterior
seat
a' upon the burner L. A screw thread
d' is
made upon the interior of the lower part of the tube I, which fits
the thread
d upon the exterior of the burner L. The
operation of this modification is as follows: when the tube I is
turned entirely onto the burner L the inner seat
a fits
down upon the shoulder
a' of the burner L, and the only
place of egress for the gas is through the slot at the tip. When
the gasoline is fresh or new, this slot will be quite sufficient to
supply the flame, but as the gasoline becomes more exhausted of
carbon, the tube or shell I may be turned up a little so that the
seat
a shall be raised slightly from the shoulder
a' and more or less of the gas will pass out through the
holes
c and pass up between the tube I and the burner L as
the tube I is turned up or down, and when the gas which escapes
through the holes
c and passes up between the tube and
burner reaches the top, it unites with that passing out of the slot
at the tip, increasing the volume and flame. In this device, the
gas, after passing out through the holes
c, is prevented
from passing down between the tube and burner by the screw threads
d1 and
d upon the inside of the tube and outside
of the burner. In the modification shown in Figs. 6, 7, 8, 9, and
10, both the burners and regulating tube are similar to that
already described, except
Page 106 U. S. 171
that the thread
d upon the outside of the burner L is
carried up higher, and the holes
c are made below the top
of the outer thread, but above the top of the inside thread. The
thread upon the inside of the tube I is not so long as the outside
thread upon the burner L, but is considerably less, so that when
the tube I is turned entirely down on the burner, the holes will be
above the thread on the inside of the tube, and there is no inside
seat in the tube I to operate upon a beveled or conical exterior
shoulder upon the burner L, as in the other modification."
"The operation of this modification is as follows: if the flame
be too weak, the tube I is turned down upon the burner L until the
top of the inside thread of the tube begins to pass below the holes
c, when the gas will escape and pass up between the tube
and burner and increase the flame as before. If it should be
desirable to stop the escape of gas through the holes
c,
it is only necessary to turn up the tube upon the burner, and when
the thread inside the tube covers the holes
c, then there
will be no escape of gas. It will be seen that the principles of
the operation of both modifications are very much alike and are
intended to accomplish the same object, although the tube turns up
in the first case to let out more gas, while it turns down in the
second case, both being equivalent, however, in their operation and
accomplishing the same result. I am aware that gas burners have
been heretofore made to give an additional supply of gas to the
flame, but in those that I have seen, they consisted of more pieces
and were considerably more expensive to manufacture, and in their
poweration the burner revolved with the tube, thus causing the
flame to revolve also. This is very objectionable, as it is often
desirable to have the flame stand in one particular direction. In
this device, the flame does not turn in the least, while the whole
burner may consist of only two pieces and is cheaply made, and its
operation and effect are perfect."
The claim of that patent is
"An improved gas burner consisting of the burner or pillar L,
having holes
c c therein and provided with the movable or
adjustable shell or tube I, all constructed and operating
substantially as and for the purposes herein described and
specified."
After such certificate was signed and filed, the Gilbert &
Barker Manufacturing Company, one of the defendants in this suit,
brought a suit in equity in the court below, as owner of the said
patent granted to John F. Barker, for the infringement of the same
against Clough, the plaintiff in this suit,
Page 106 U. S. 172
alleging as the infringement the making and selling of burners
constructed exactly like the two forms described in the patent to
said Barker. The only testimony taken directly in the present suit
was that taken on the trial before the jury and embodied in the
case made, on which the motion for a new trial was made. But
considerable testimony was taken for final hearing in the suit
against Clough, and that testimony is contained in the record in
this case, and it is understood that such testimony was considered
and used, by agreement of parties in the court below, as part of
the proofs in this case.
The first claim of the Clough patent is a claim to "the batwing
burner, perforated at the base, in combination with the surrounding
tube, substantially as described." The elements of this claim are a
batwing burner with a burner tube, the burner tube perforated at
its base with small holes or passages for gas to escape at the base
of such burner tube, and another tube, surrounding the burner tube,
open at the top and closed at the bottom and united to the burner
tube below the perforations in it. The method of regulating the
escape of gas from the perforations is no part of the first claim.
The office of the combination in the first claim is, as the
specification states, to enable the surrounding tube to direct to
the tip of the burner the gas which comes through the perforations,
such surrounding tube being open at the top and closed at the
bottom and united to the burner tube below the perforations.
Two forms of burner are presented as infringements of the first
claim. They are both of them substantially like the first form of
burner described in the patent of Barker, the outside tube in both
of them turning up to let out more gas. Each of these burners
contains the combination of the first claim of the Clough
patent.
It was held by the court below that the combination covered by
the first claim of the Clough patent was found in a burner called
the Horace R. Barker burner, the existence of which prior to
Clough's invention was held to have been satisfactorily proved. Of
the Horace R. Barker burners, it was said by the court:
"In those burners, the burner was a batwing burner, perforated
at the base. The perforations did not consist of small holes, but
the stem of the burner was slitted all the way
Page 106 U. S. 173
down to the base, allowing the gas to escape through the whole
length of the slit. There was a surrounding tube united to the
burner below the lower end of the slit. The burner stem had a cone
near its top, and when the surrounding tube was screwed so as to be
in a certain position with reference to such cone, the effect was
to direct to the tip of the burner the supply of gas coming through
the slit below, the surrounding tube being open at the top and
closed at the bottom, and the flame was thickened, and a ring of
flame was formed. The structure and mode of operation of the
combination were the same as those of the combination covered by
the first claim of the plaintiff's patent. The fact that the
perforations in the Horace R. Barker burner existed not only at the
base, but were continued in the form of a slit all the way up makes
no difference. Nor does it make any difference that the Horace R.
Barker burner had a cone near its top. The first claim of the
plaintiff's patent is broad enough to cover the Horace R. Barker
burner, and that claim must be held to be invalid for want of
novelty."
On the trial before the jury, the existence and operation of the
Horace R. Barker burners were testified to by Horace R. Barker
himself and by John F. Barker, and a copy of the rejected
application of Horace R. Barker for a patent was put in evidence.
The question was submitted to the jury by the court as to whether
the effect produced by Clough's invention had been produced in the
Horace R. Barker burner by a combination or mode of operation
substantially the same as in the burner of Clough, and the
attention of the jury was called by the court in its charge to the
contention of Clough that the object of the Horace R. Barker burner
was to control the size of the slit in the burner by a clamp; that
if some gas escaped through an orifice at the top of the
surrounding tube and was projected upon the burner tip, the escape
was accidental and not desired, and that in a well made burner, it
was not intended to escape and did not escape. The jury found for
Clough on the question of novelty as against the Horace R. Barker
burner. When the motion for a new trial was made before the judge
who presided at the jury trial, he said in his opinion denying the
motion:
"The device mainly relied upon by the defendants upon the
question of priority was a burner of Horace R.
Page 106 U. S. 174
Barker, for which he made an unsuccessful application for a
patent prior to the date of the plaintiff's invention. It consisted
of a batwing burner, slitted nearly to the base, and a surrounding
tube smaller at the top than at the bottom. There was a screw upon
the inside of the lower part of the tube. When the tube was screwed
down upon the burner, the top of the tube pressed against a conical
and enlarged part of the burner near its top, and the slit was
closed. When the tube was screwed up, the slit was enlarged. The
defendants claimed that the top of the tube, in connection with the
protuberant part of the burner, formed a valve, and that the gas
passed to the tip not only through the burner, but through the ring
near the tip at the end of the surrounding tube in a double
current, and that the device was substantially like the burner of
the complainant. The complaint claimed that the object and the
effect of this invention was to provide a burner in which the
batwing slit could be enlarged or diminished at pleasure, and to
consume but a single current of gas; that the top of the tube, in
connection with the conical part of the burner, was not a valve but
a clamp; that when the burner was new or well made, this clamp
prevented the escape of gas, and that there was no appreciable
delivery of gas in a well made burner except through the tip. I am
of the opinion that the jury, upon this question of fact, did not
misconceive the weight of the evidence."
In the proofs taken in the suit against Clough and used in this
case by agreement, John F. Barker gave further testimony as to the
prior use of the Horace R. Barker burners, and such testimony seems
to have been understood by the court below as showing that the
Horace R. Barker burner was used with the surrounding tube raised
to such a height that the horizontal line of its upper end was
raised from its seat at the cone on the burner pillar, and an
additional supply of gas passed out of the top of the surrounding
tube and mingled with the gas which escaped from the burner tip;
that by screwing down the surrounding tube so that it would impinge
sufficiently against the cone, the slit would be closed; that the
effect of the operation of thus raising or lowering the surrounding
tube was to increase or diminish the supply of gas, and that the
surrounding tube, considered in connection with the cone on the
pillar
Page 106 U. S. 175
of the burner, operated as a valve to control the flow of gas.
In this view, the structure and its mode of operation were held to
be such as to anticipate the first claim of the Clough patent. But
we are all of opinion that an erroneous view was taken of the
purport of the additional testimony of John F. Barker. He was
testifying in February, 1875. The question was as to what the
Horace R. Barker burner was, and as to what was its mode of
operation in use. In the specification of the patent of John F.
Barker, issued in July, 1870, he said:
"I am aware that gas burners have been heretofore made to give
an additional supply of gas to the flame, but in those that I have
seen, they consisted of more pieces, and were considerably more
expensive to manufacture, and in their operation the burner
revolved with the tube, thus causing the flame to revolve
also."
The expression "more pieces" means more pieces than in the
burner he was patenting. His burner consisted of two pieces only.
The Clough burner consisted of three pieces, and in it the burner
revolved with the tube. In the John F. Barker patent, the burner
did not revolve with the tube. The Horace R. Barker burner
consisted of two pieces only, and the burner did not revolve with
the tube. Therefore the reference by John F. Barker in his patent
to the burners which he had seen, which would give an additional
supply of gas, was to the Clough burners, which it is proved he had
seen, and it is impossible that he could have then understood that
the Horace R. Barker burners, which also he had seen, were burners
which had been used to give an additional supply of gas to the
flame.
The testimony as to any additional or supplementary supply of
gas in the Horace R. Barker burner amounts really to this only:
that if that burner is used now in a way in which it was never
designed to be used, and is not shown to have ever been used before
Clough's invention, it may be made to furnish a supplementary
supply of gas. Its structure was such that, to give full effect to
its mode of operation, the surrounding tube did not require ever to
be raised so high as not to be in contact with the cone. As it was
raised from its lowest position the slit opened, and when the slit
was opened to its full extent the tube was still in contact with
the cone, and there was no orifice between them. Any further
raising
Page 106 U. S. 176
of the tube was accidental, and not a part of the law of the
structure. The object of raising and lowering the tube was, by less
or greater pressure on the cone, to open or close the slit in the
burner. The specifications of Horace R. Barker in his rejected
application, shows that the only object of his burner was to
control the flow of gas through the slit in the burner, instead of
controlling the flow at the cock or further back. The spring of the
two parts of the burner was intended to carry them away from each
other, and open the slit when the pressure of the tube against the
cone was relieved, while the increased pressure of the tube against
the cone closed the slit. Any raising of the tube unnecessarily
high, so as to admit of a flow of gas through an orifice between
the tube and the cone to the flame, cannot be regarded as amounting
to an invention of what Clough invented. The structure was not
designed for the same purpose as Clough's; no person looking at it
or using it would understand that it was to be used in the way
Clough's is used, and it is not shown to have been really used and
operated in that way.
The foregoing remarks apply equally to the Coolidge burner,
which was like the Horace R. Barker burner in structure, except
that in the Coolidge burner, the raising of the ring against an
inverted conical projection closed the slip. The Solliday burner
and the Lunkenheimer burner did not contain Clough's invention. We
are therefore brought to the conclusion that the first claim of the
Clough patent is valid.
The second claim of the Clough patent is for a combination of
the batwing burner, perforated at the base, the surrounding tube
and the tubular valve for regulating the supply of external gas to
the burner, substantially as described. The specification describes
the tubular valve as extending upward into the burner tube. The
view taken by the court below as to this second claim was that
there was in the Horace R. Barker burner a regulation of a
supplementary flow of gas, and by a valve arrangement the raising
of the tube above the cone, allowing the gas to flow out of the
tube, and the lowering of the tube to bear against the cone closing
the orifice. The court said:
"In view of the existence of that burner, which contained the
combination of a batwing burner, a perforated
Page 106 U. S. 177
tube in substance like that of the plaintiff's patent, and a
tubular valve for regulating the supply of external gas to the
burner, the construction of the second claim of the plaintiff's
patent must be such as to limit that claim to the form of tubular
valve which he describes, namely one in the interior of the burner
tube and not forming part of the surrounding tube. Under this
construction, the second claim of the plaintiff's patent is not
infringed."
The defendants' burners had no tubular valve extending up into
the burner tube. In them, the tubular valve formed part of the
surrounding tube, and reached or left its seat by screwing down or
up the surrounding tube. The surrounding tube could not be
permanently attached to the burner, because it carried the movable
valve. In the Clough burner, the surrounding tube may be
permanently attached to the burner, because the tubular valve is
not carried by the surrounding tube, but is a third and separate
instrument, carried by an adjustable cylinder inserted within the
burner tube from below.
The combination of the first claim of the Clough patent being
new, and consequently there never having been any valve arrangement
applied to regulate the flow of gas in such a combination, the
premises on which the decision of the court below proceeded fail.
Clough is entitled to the benefit of the doctrine of equivalents as
applied to the combination of the burner, surrounding tube, and
regulating tube, covered by the second claim of his patent. The
regulation in the defendants' burners was by a tubular valve on the
outside of the perforation instead of on the inside, and performing
its work by being screwed up or down, as in Clough's. Although in
the Clough structure the burner and surrounding tube revolve
together in adjusting their position in reference to that of the
tubular valve, so as to let in or turn off the supply of gas
through the perforations, and although in the Clough structure the
flame revolves by the revolution of the burner, and although in the
defendants' burners the revolution of the surrounding tube
regulated the supply of gas through such perforation, and neither
the burner nor the flame revolved, the defendants' valve
arrangement must be held to have been an equivalent for that of
Clough to the full extent to which that of Clough
Page 106 U. S. 178
goes, involving perhaps patentable improvements, but still
tributary or subject to the patent of Clough. It is true that that
patent describes the tubular valve as being inside of the burner
tube. But Clough was the first person who applied a valve
regulation of any kind to the combination to which he applied it,
and the first person who made such combination, and he is entitled,
under decisions heretofore made by this Court, to hold as
infringements all valve regulations applied to such a combination
which perform the same office in substantially the same way as, and
were known equivalents for, his form of valve regulation. The
record shows that prior to the existence of the appellant's burner,
it was common in gas burners to check the flow of gas out of the
burner by applying an obstruction operated by a screw indifferently
outside or inside of the burner. It follows from these
considerations that the defendants infringed the second claim of
the Clough patent.
The decree of the circuit court is reversed, with costs, and the
cause is remanded with directions to enter a decree for the
appellant for an account and an injunction, as prayed in the bill,
with costs, and to take such further proceedings therein as shall
be in conformity with law and with the opinion of this, and it
is
So ordered.