A given association of mechanical elements may be entirely new, but it
does not follow that it forms a patentable association, for not all
new things are patentable. If the new association is a combination, it
is patentable, but if it is a mere aggregation, it is unpatentable. An
association may be new and still all of its separate elements may be
old, the act of invention lying in the fact that the elements have
been so associated with relation to each other as to bring about an
improved result, or an improved means for an old result. All new
machines are, after all, composed of old elements. The law presupposes
that the elements are old, and that the invention resides in the
peculiar association of them. If we take a given mechanical element,
recognized as having had a certain capacity, and if we then similarly
take some other mechanical element and employ it only for its
previously recognized capacity, and if we then add the third element
for its recognized capacity, we have in the end only an association of
three elements each performing its well recognized individual office,
and the entire association performing only the sum of the recognized
individual elements. Such an association is a mere aggregation, a mere
adding together of elements, without making the sum of the results any
greater in the association than it was in the individual elements. It
is simply adding two to one and getting three as a result. An
aggregation is unpatentable. As an illustration, a heavy marble statue
of Jupiter is found in the parlor and difficult to move. Ordinary
casters are put under its pedestal and it becomes easier to move.
Modern anti-friction two-wheeled casters are substituted for the
commoner casters, and the statue becomes still easier to move. Casters
were never before associated with a statue of Jupiter. Here is a new
association, but it is a mere aggregation. The statue of Jupiter has
been unmodified by the presence of the casters, and the casters
perform precisely the same under the statue of Jupiter that they did
under the bedstead. There is no combined result, and there is no
patentable combination.
But if an inventor takes a given mechanical element for the purpose of
its well recognized capacity, and then associates with it another
mechanical element for its recognized capacity, but so associates the
two elements that one has a modifying effect upon the capacity of the
other element, then the association will be capable of a result
greater than the sum of the results for the individual elements. This
excessive result is not due to the individual elements, but to the
combination of them. One has been added to one and a sum greater than
two has been secured. The modification of result may be due merely to
the bringing of the two elements together, so that they may mutually
act upon each other, or it may be due to the manner or means by which
they are joined. In a patentable combination the separate elements
mutually act upon each other to effect a modification of their
previous individual results, and secure a conjoint result greater than
the sum of the individual results. The elements of a combination need
not act simultaneously; they may act successively, or some may act
without motion. As an illustration, assume an old watch in which there
was a stem for setting the hands, and assume another old watch with a
stem for winding the spring. If an inventor should make a watch, and
provide it with the two stems, he would have only an aggregation. But
if he employed but one stem, and so located it that it could be used
at will for setting the hands or for winding the spring, then he would
have produced a combination. The particular instance just given is not
a case of the same number of elements, producing a result in excess of
the individual results of the separate elements, but is rather a case
of a lesser number of elements, producing a combination result equal
to the sum of the previous results of a greater number of elements. A
better example would perhaps be a new watch with its two old stems so
related that either could be used for setting the hands or for winding
the spring.