If there be any invention in the machine patented to Martin R.
Roberts by reissued letters patent No. 7341 for an improvement in
coal screens and chutes, dated October 10, 1876 (upon which the
court expresses no opinion), it is clear that it was not infringed
by the defendant's machine. The Court takes judicial notice of the
fact that hoppers with chutes beneath them are used for many
different purposes.
Page 156 U. S. 612
This was an action at law by the Excelsior Coal Company to
recover damages for the infringement of reissued letters patent No.
7,341, granted October 10, 1876, to Martin R. Roberts, for an
"improvement in coal screens and chutes."
It seems by the statement of the patentee that, previous to this
invention, in unloading vessels of coal the coal had, for the most
part, been hoisted from the hold, over the bulwarks, and dumped
upon the wharf or upon the coal previously dumped, or, if chutes
were used, such chutes were fixed; nor, so far as the patentee was
aware, had a movable chute ever been known or used by which the
coal could be received from the vessel at any point on the wharf,
and be screened and delivered to the cart. The patentee further
states in his specification:
"My invention consists of a portable apparatus for receiving
coal from the bucket by which it is hoisted from the ship, and for
screening and delivering it to carts on the wharf, said apparatus
being adapted for ready removal from place to place when
required."
"By this apparatus, I am able to save repeated handlings and
consequent expense and the breakage of the coal, and the apparatus
can be changed from one point to another where the vessel may be
placed."
The invention is shown in the following drawing:
Page 156 U. S. 613
image:a
The invention in question consisted substantially of a strong
frame (A) surmounted by a hopper (BB') in the form of a trough,
into which the coal is dumped from the hoisting buckets. The coal
falls through the hopper upon an inclined screen (D) whose meshes,
constructed of horizontal wires, are coarse enough to detain only
the larger lumps, which accumulate in a reservoir (O) formed by the
screen on one side, and three inclined surfaces on the other. This
reservoir is in fact a secondary hopper at the bottom of which is
located a chute (F) and gate (
h) through which the large
coal is drawn off as required into the cart or other vehicle. The
smaller coal, which passes through the meshes of the screen (D)
falls upon a second inclined screen (I) standing transversely to
the upper one, whose meshes are finer than the other. The coal is
again shifted by this screen into two grades, the coarser of which
is discharged down the incline at one side of the machine, while
the finer falls through the meshes upon the floor or wharf beneath
the frame.
The patentee further added in his specification:
"The frame
Page 156 U. S. 614
(AA) will be mounted upon small wheels, so that it can be moved
from one place to another upon a wharf in order to be placed in
position to receive the discharging cargo of different ships; but
when moving it from one wharf to another, I employ axles across
each end of the frame, upon which strong wheels are placed, so that
the entire machine can be drawn along similar to any vehicle. . . .
When it is not desired to screen the article or substance to be
unloaded, a false bottom or metal blank (K) is placed upon the
granting or inclined side (D) of the reservoir, so that the
substance will be carried directly through the chute into the cart
or wagon intended to convey it away."
Plaintiff relied upon an infringement of all the claims of the
patent, which read as follows:
"1. A portable combined coal receiving, screening, and
delivering apparatus, arranged to receive the coal or other cargo
from a swinging suspended tub or bucket, by which it is hoisted
from the hold of a ship or other watercraft, and to screen it
automatically, and deliver it into carts; said apparatus being
constructed and arranged substantially as described."
"2. The receiving hopper (BB') in combination with the reservoir
(O) with its screen or granting side (D), chute (F), with its
toothed gate (
h) and one or more independent screens (I),
all combined and arranged substantially as and for the purpose
above described."
"3. The metal blank or false bottom (K), in combination with the
receiving hopper (BB'), reservoir (O), chute (F), and gate
(
h), substantially as and for the purpose above
described."
"4. The combination of the hopper (BB') for receiving the coal
from a swinging bucket, the reservoir (O), arranged to receive the
coal as it passes from the hopper, with the chute (F) and gate
(
h), all constructed to operate substantially as and for
the purpose set forth."
"5. In combination with the elongated hopper, the screen (D),
reservoir (O), and chute (F), with its gate (
h), the
combination being substantially as is herein set forth."
The case was tried before a jury, and resulted in a verdict of
$8,830.90 for the plaintiff, upon which a judgment was
subsequently
Page 156 U. S. 615
entered. To review this judgment. the Black Diamond Coal Mining
Company, defendant therein, sued out this writ of error.
MR. JUSTICE BROWN, after stating the facts in the foregoing
language, delivered the opinion of the Court.
There are thirty-nine assignments of error in this case, but, in
the view we have taken, it will only be necessary to consider the
twenty-first, which is:
"That the court erred, upon the close of all the testimony in
the case, and upon the request of the defendant's counsel, to
instruct the jury to render a verdict in favor of the
defendant."
The patent in question is for a portable coal screening device,
which may be moved to any place on the wharf where a vessel happens
to be discharging her cargo. The portability of the device,
however, is not mentioned in any of the claims except the first,
which also includes the screen as an element of the combination.
The coal is hoisted from the hold of the vessel in buckets or tubs,
which are swung over the machine, and the coal dumped into the
hopper, through which it falls upon the first screen and lodges in
the reservoir until required for use, when the coarser coal slides
down upon a chute, having an outlet or gate, through which it is
withdrawn into carts. The finer coal falls through the first screen
upon a second, where it is again sifted, the coarser sliding down
to the side of the machine, the finer falling through the meshes
upon the wharf, directly beneath the hopper.
The defendant also uses a portable machine consisting simply of
a square hopper of the form ordinarily used in grist mills and
elevators, through which the coal of all sizes falls directly upon
a chute having an outlet or gate towards, but some distance from,
the bottom, which can be raised or lowered at pleasure, and through
which the coal is withdrawn
Page 156 U. S. 616
as required. There is no provision whatever for screening the
coal shown in the drawings of defendant's chutes put in by one of
plaintiffs' witnesses, nor in his model introduced as an
exhibit.
As the combinations described in the first second, and fifth
claims of the Roberts patent include a screen or screens as an
element, it is entirely clear that the defendant's machine, as
above described, does not infringe those claims.
The third claim includes the metal blank or false bottom (K), in
combination with the receiving hopper (BB'), reservoir (O), chute
(F), and gate (
h), the fourth claim -- the combination of
the hopper, the reservoir, the chute, and the gate -- differing
only from the third in the omission of the metal blank or false
bottom.
Now in determining the question of patentability raised by the
twenty-first assignment of error, we are to take into consideration
only the device alleged to be infringed. Granting, for the purposes
of this case, that the combinations set forth in the first, second,
and fifth claims, of all of which the screens are an element,
constitute a patentable invention, it does not follow that if these
screens be omitted, as they are by the substitution of the false
bottom or metal blank (K) in lieu of the upper screen, this
machine, which is the only one alleged to be infringed by the
defendant, contained a patentable combination. Eliminate the
screens by the substitution of the false bottom, and there is
nothing left but an elongated hopper, a reservoir beneath, a chute,
and a gate. Hoppers with chutes beneath them have been used for a
dozen different purposes, but principally for grain elevators, by
means of which vessels lying alongside a wharf are loaded in a
fraction of the time required by hand or animal power. Indeed,
these devices are so common that we think judicial cognizance may
be taken of them.
Brown v. Piper, 91 U. S.
37;
Terhune v. Phillips, 99 U. S.
592;
King v. Gallun, 109 U. S.
99;
Phillips v. Detroit, 111 U.
S. 604.
If there be any invention at all, then, in the combinations
specified in the third and fourth claims, it is in the introduction
of the reservoir (O) beneath the hopper, which is really
Page 156 U. S. 617
an enlargement of the chute, for the purpose of affording a
lodgment for the coal until it is drawn off for use. Great stress
was laid by plaintiff's counsel upon this feature of the invention,
but, even conceding it to be patentable, there is nothing
corresponding to it in the defendant's machine. On the contrary,
the coal falls through a square opening in the bottom of the
hopper, directly upon the chute, where it is detained by a gate,
which is kept closed until the coal is withdrawn. It is evident
that the hopper itself is substantially the only reservoir,
although a small amount of coal is necessarily detained in the
upper part of the chute until the gate is raised. The chute is
nowhere enlarged to form a reservoir.
The fact that the machine is portable undoubtedly adds to its
usefulness, but its portability is only made an element of the
first claim, of which the screens are also an element. So that, if
portability were itself a patentable feature, which it is not --
Hendy v. Iron Works, 127 U. S. 370 --
there is no infringement of the first claim, as the defendant does
not use the screens.
There was some evidence tending to show that one of the machines
used by the defendant was provided with a chute, the bottom of
which consisted of a screen, and that it was used until about the
time this suit was brought, when the screen was covered over with
planking, and the bottom of the chute made solid. This machine
doubtless approximated more closely to that described in the
plaintiff's patent. No attempt, however, was made to separate the
damages arising from the use of this device from those arising from
the use of the chute with the solid bottom. The trial appears to
have proceeded largely upon the theory that there was no
distinction between the two devices. The court instructed the jury
that the plaintiff's patent was not limited to a device in which a
screen is one of the elements, and that if they found that
defendant had used a device substantially identical with the device
shown in the patent, but having a solid bottom to the reservoir and
a chute which extends from the receiving hopper, instead of having
a screen bottom, such device was also covered by the patent, and
was an infringement.
Page 156 U. S. 618
An exception was taken to this portion of the charge, and the
twenty-fourth assignment of error was intended to cover it. For the
reasons given above, we think the court erred in its interpretation
of the patent. If there was any invention at all disclosed, it was
in the use of the reservoir and the screening device, and, without
expressing an opinion upon this point of patentability, it is clear
that no infringement was involved in the use of defendant's hopper
and chute, with or without a solid bottom, if for no other reason,
because it lacked the reservoir of the plaintiff's patent.
There was no question to go to the jury in the case, and the
court should have directed a verdict for the defendant.
The judgment of the court below is therefore
Reversed and the case remanded with directions to set aside
the verdict and grant a new trial.
