1. Letters patent No. 133,638, granted Dec. 3, 1872, to William
Johnson, for an improvement in wrenches, do not infringe reissued
letters patent No. 6026, granted Aug. B, 1872, to John Lacey and
George B. Cornell, for an improvement in wrenches for extracting
2. The doctrine of mechanical equivalents has no application to
This is a suit by George B. Cornell, against Eilert Schumacher
and William Johnson, for an injunction, and for damages claimed for
the alleged infringement by them of reissued letters patent No.
5026, granted Aug. 6, 1872, to John Lacey and George B. Cornell,
for an improvement in wrenches for extracting bung-bushes; said
letters being a reissue of original letters No. 118,617, dated Aug.
The defendants justified under letters patent No. 133,536,
issued to Johnson Dec. 3, 1872, for an improvement in wrenches.
The specification and claim of both patents are fully stated in
the opinion of the Court.
The drawing therein referred to are as follows:
Page 96 U. S. 550
Page 96 U. S. 551
The court below decreed in favor of the complainant, and awarded
him an injunction, whereupon the defendants appealed to this
Page 96 U. S. 552
MR. JUSTICE SWAYNE delivered the opinion of the Court.
This is a suit in equity founded upon reissued patent No. 5026.
The reissue is for "an improved wrench for securing metallic
bushing in casks and barrels," and bears date on the 6th of August,
1872. The appellee is the complainant.
The bill alleges infringement, and prays for an injunction and
The answer denies the infringement, and sets up several other
This opinion will be confined to the question of
The description of the appellee's wrench and his claim are thus
set forth in the reissue:
"The present invention relates to a wrench employed in securing
a metallic bung-bushing within the aperture of casks, barrels,
&c.; and the improvement consists in providing the shank of the
wrench with a cylindrical core so arranged as to closely fit the
aperture in the bushing, and a V-shaped projection adapted to fit a
corresponding notch formed in the bushing, whereby the same may be
turned into place without assuming an oblique position within the
bung-opening, and also preventing the wrench from slipping from its
seat; all of which will be more fully understood by the following
"In the drawing, A represents the shank of the wrench, which
consists of a plain metal bar of the requisite length. Attached to
one end of this bar is a flat metal plate, B, which is provided at
its center with an elongated mortise, C, as shown in Fig. 1. This
shank is so formed at its junction with the plate as to provide a
V-shaped projection, D, the point of which extends forward toward
the center of the plate. E represents a cylindrical cast-metal
core, which is made tapering, and so arranged as to fit the
aperture in the bushing. This core is made separate from the plate,
and is attached thereto by means of a bolt, F, which passes through
the mortise formed in the plate, as shown in Fig. 2. The
arrangement of this core is such as to admit of being removed from
the bolt by removing the nut e
, the object of which is to
allow a core of greater diameter to be substituted when used in
bushings of large size, provision being made for the elongation of
the mortise in the plate for the moving of the bolt toward or from
the projection D, which becomes necessary when cores of different
sizes are used."
"In using the said invention, the core is inserted into the
Page 96 U. S. 553
through the bushing, and turned until projection D falls into a
notch formed in the bushing, which is adapted to fit the same; and
by means of the core the bushing is kept steady, and prevented from
assuming an oblique position in the bung-opening while being turned
into place, and by the contact of the projection within the notch
the wrench is prevented from slipping from its seat, thereby
enabling the bushing to be readily turned into place."
"We do not wish to confine ourselves exclusively to the V-shaped
projection, as any form that will prevent the core from turning
independent of the bushing will produce the same result."
"Having thus described the said invention, we claim:"
"The wrench herein described, consisting of a shank, A, plate,
B, projection, D, and core, E, the said core adapted to fit the
opening through the bushing, whereby the same is prevented from
assuming an oblique position when being turned into place,
substantially as described."
The wrench of the appellants, out of which this controversy has
grown, is also covered by a patent, but of later date than the
appellee's. The specifications and claim of this patent are brief
They are as follows:
"DESCRIPTION OF THE DRAWING FORMING PART OF THE
"Fig. 1 is a sectional view of the wrench; Fig. 2, a perspective
view of the wrench and bushing."
"A is the handle of the wrench; B, the projection which fits
into the inside of the bushing; C, a rod which runs down through
the projection B in a hole nearer one side than the other; D, a
piece on the end of the rod C which fits into a recess in the
bottom of B; E, a knob on the top of rod C; F, spring on rod C,
under knob E, which holds the rod C up in place; G, a screw in the
top of rod C, which holds knob E on securely in place; H, the bush;
I, the projection on the bottom of the bushing which the part of
the wrench D strikes against to screw the bushing into place."
"The operation of this wrench is as follows: the part B is
placed in the bush, and the operator then takes hold of the knob E
and turns it, and, as it turns, the part D at the bottom is turned
out and catches against the projection I in the bushing, and then
the handle A and the bush will turn with it and be screwed home.
Page 96 U. S. 554
"NATURE AND OBJECT OF THE INVENTION"
"My invention is a wrench to screw bung-bushings into
beer-barrels, and fits into the opening and strikes against a
projection on the bushing at the inner end of the bush, thus
preserving the whole strength of the bushing. The notch on the
outer side of the bushing, which weakens it, is avoided."
"The combination and arrangement of projection B, rod C, piece
D, and knob E, substantially as and for the purpose set forth."
Models of both instruments have come up with the record, and are
in evidence. They are made in conformity to the respective
specifications of the parties. The mind is much more effectually
assisted in these cases by such aids than is possible by any
drawings and description, however full, without them. We are thus
enabled in this case readily to come to satisfactory
Wrenches are very old. They have long been used for various
purposes in the mechanic arts. Numerous cuts representing them in
different forms are found in Knight's Mechanical Dictionary, pp.
1473, 1711, 2821.
The patent is well entitled for an improvement. It could be for
Nothing is claimed separately. Everything is claimed together
and in the aggregate. If anything was withdrawn, and no equivalent
supplied in its place, the instrument would be a failure. Each
element is a part of a compound unit, and is necessary to the
completeness and efficacy of the result.
A combination is always and entirety. In such cases, the
patentee cannot abandon a part and claim the rest, nor can he be
permitted to prove that a part is useless, and therefore
immaterial. He must stand by his claim as he has made it. If more
or less than the whole of his ingredients are used by another, such
party is not liable as an infringer, because he has not used the
invention or discovery patented. With the change of the elements,
the identity of the product disappears. Vance v.
1 Black, 427.
But whether the patent here is for a combination or not is,
Page 96 U. S. 555
in our view, not material. If the negative be conceded, we think
the differences in the two instruments are so radical that the end
of this litigation must be the same.
Upon examining the models and specifications of the parties, it
is found that the appellants have nothing in common with the
appellees in several important particulars. They have not the flat
plate B, nor the mortise C, nor the V-shaped projection D, nor the
bolt F, as shown in Fig. 2, nor any arrangement touching the core
whereby it can be removed, and one of larger diameter be
substituted, when the size of the cavity of the bush requires such
a change, and there is no notch in the flange of the bush such as
that to which the appellee's wrench is applied, and hence no
projection to fit into such an indentation. Without both these
things, the appellee's wrench would be entirely useless. They are
therefore vital in the invention covered by his patent. The notch
is the point of engagement between the bushing and the wrench when
the latter, operating as a lever, gives the former its circular
motion, and thus forces it home. Without this arrangement such
motion could not be communicated and the desired result produced.
Hence its importance in the scheme of the invention. Without it,
the rest would be as worthless for the end in view as one blade of
a pair of scissors disjoined from the other.
The appellants thought this notch arrangement seriously
objectionable. They claimed that it weakened the flange of the
bush, and that the application of the leverage necessary to give
the bush the requisite circular motion until the work is done not
unfrequently involved its destruction. They sought to obviate the
difficulty by an invention of their own.
The first thing to be done was to change the bush so as to give
it the desired strength. This could be effected only by dispensing
with the notch. That was done.
Then it was indispensable that something should be substituted
whereby the necessary turning motion could be given by the wrench
to the bushing without injuring or destroying the latter. For this
purpose, a projection was put on the inside of the bush, low down.
This strengthened rather than weakened it.
Bushes, like wrenches, are very old. They are not here in
Page 96 U. S. 556
question. If they were, certainly the appellants had the same
right to make them with the inner projection that the appellee had
to make them with the outer notch.
But although the appellants' bush was unexceptionable, there was
no wrench known in mechanics whereby it could be made to operate.
The appellee's wrench was inapplicable. Projection D in his wrench,
as regards such purpose, might as well have been anywhere else. It
could have no possible relation of cause and effect to the thing to
be done. The appellants entered the new and unoccupied field before
them and succeeded. Their wrench has a projection or core
attachment, which is inserted into the bush. Through this core runs
a rod with a latch at the lower end, which fits into a recess at
the bottom of the core. The core is introduced into the bush; the
latch is turned by means of a knob at its top, so as to catch
against the projection in the bush. The force of the wrench then
being applied, the bush is readily screwed to its place. This was
the last stage in the process of the invention.
The doctrine of mechanical equivalents has no application here,
and need not be considered. The two instruments are separated by a
broad line of demarcation. There is nothing in the appellee's which
is suggestive of anything in the appellants'. No one from studying
the former would have been thereby led to the results embodied in
the latter. They are at opposite poles. Unless the appellee is
entitled to claim every form of wrench applicable to bushes
invented after his own, his bill cannot be maintained.
The appellants seem to have considered his machine as a thing to
be shunned, rather than to be followed. There is certainly not less
of novelty, utility, and invention in their wrench than in his.
Whether his patent is or is not for a combination, the facts are
alike fatal to this suit. There has been no infringement by the
The decree of the circuit court will be reversed, and the case
remanded with directions to dismiss the bill, and it is