A patent for a lead-holding tube of a pencil having at the lower
end two or more longitudinal slots, a screw thread inside, and a
clamping sleeve outside, each part of which, as well as the
combination of two or more slots with the sleeve, or of a single
slot with the screw thread, has been previously used in such tubes,
is void for want of invention.
Page 127 U. S. 397
Bill in equity to restrain alleged infringements of letters
patent. Decree dismissing the bill. Complainant appealed. The case
is stated in the opinion.
MR. JUSTICE GRAY delivered the opinion of the Court.
This is an appeal from a decree dismissing a bill in equity for
the infringement of letters patent granted to the plaintiff January
22, 1884, for "improvements in lead holders for pencils," which
(omitting the drawings and the explanation of them) fully shows the
invention claimed, and the form of lead holders or lead tubes
previously in use, and known to the patentee, as follows:
"The object of my present invention is to hold the lead or
crayon in pencils from slipping back within the tube when pressed
upon by the tube when pressed upon by the lead. Lead tubes now in
common use are usually slotted at the lower end to form elastic
clamping fingers, which fingers are closed upon the lead near its
point end by a sleeve or a tube which moves longitudinally over the
fingers. These fingers are either smooth upon the inside or
terminate at their ends in sharp inward projections or claws. The
first kind soon become so smooth that the lead slips back when
borne upon in the act of writing, and the second frequently breaks
the lead when the clamping sleeve is tightened up, and when
tightened up carefully, the lead often breaks in use when writing
with the pencil inclined. I overcome both these objections by
making a fine screw thread within the lower end of the tube before
it is slotted to form the clamping fingers. The clamping fingers
may, instead of being screw threaded upon the inside, be serrated
or roughened, to accomplish the same result; but the screw thread
is much better, because by this means a uniformly even roughened
surface can be made
Page 127 U. S. 398
within the lower end of the tube at comparatively small expense,
and, as these pencils are designed to take the place of the common
lead pencil, they must be made cheaply to insure their introduction
into general use."
"I am aware that it is old to provide a pencil case for holding
ordinary lead pencils with a sliding ring, to which are secured
spring clamps having their holding surfaces serrated, and having
their shanks bent to approach each other, then jut outwardly and
downwardly at their free ends, so that a ring slide may be moved
upon said shanks to cause the free ends of the clamps to grasp or
release a pencil, and I am also aware that it is old to provide the
lead-holding tube of a pencil with an interior thread and a single
slot. I therefore do not claim either of these devices."
"I claim as my invention:"
"1. As a new article of manufacture, a lead tube for pencils,
consisting, substantially as before set forth, of a tube provided
at one end with internal or female threads, and two or more
longitudinal slots to form threaded fingers."
"2. The combination, with the lead tube provided at one end with
internal threads and two or more longitudinal slots, of a clamping
sleeve adapted to be adjusted upon the slotted end of the tube to
press the threaded fingers upon a lead, substantially as
described."
It thus appears upon the face of the plaintiff's specification
that there were already in use lead-holding tubes for pencils with
two or more slots at the lower end, so as to form elastic clamping
fingers, closing upon the lead by means of a sliding sleeve, as
well as tubes with a single slot and an interior screw thread.
The slots, the screw thread within, and the outer sleeve being
all old, and the combination of two or more slots with the sleeve,
or of a single slot with the screw thread, being also old, it is
too clear for discussion that to make two or more slots in a tube
threaded inside and sleeved outside required no invention, and it
is therefore unnecessary to consider the evidence upon the question
whether the plaintiff was the first person who did this.
Decree affirmed.