1. A patented device for fastening together the metal cap and
sleeve of an incandescent electric lamp socket, consisting of
corresponding recesses and protrusions in the inner surface of the
cap and the outer surface of the sleeve, respectively, formed by
slitting the metal transversely and stamping it, which lock,
against longitudinal movement only, by an automatic snap action
when the sleeve is thrust longitudinally into the cap (Patent No.
743,206, Claims 1 and 4, November 3, 1903), is not infringed by a
construction providing the cap with inwardly extended riveted studs
and the sleeve with bayonet slots which lock with the studs by a
longitudinal followed by a rotative movement, and an additional
stud in the cap which snaps into a hole in the sleeve, as the
rotation is completed, preventing reverse rotative movement. P.
256 U. S.
675.
2. The patent in suit having made no provision for a lock
against rotative movement between the cap and sleeve, cannot be
aided by resort to a later patent to the same patentee providing a
slot and projection to overcome the deficiency. P.
256 U. S.
675.
3. In view of the prior art, the patentee's concessions made in
the patent office, and his later patent,
held that the
words "telescopically received" and "telescopically applied," as
used in the patent in suit, must be restricted to a direct
longitudinal movement or thrust of the sleeve into the cap. P.
256 U. S.
676.
4. One who has specifically narrowed his claim in the Patent
Office in order to secure his patent may not afterwards, by
construction or resort to the doctrine of equivalents, give to it
the larger scope it might have had if not so amended. P.
256 U. S.
677.
262 F. 768 affirmed.
The case is stated in the opinion.
Page 256 U. S. 669
MR. JUSTICE CLARKE delivered the opinion of the Court.
This is a suit for infringement of letters patent of the United
States, No. 743,206, granted to August Weber, Sr., on November 3,
1903. The district court held Claims 1 and 4 valid and infringed,
but the circuit court of appeals, while affirming the validity of
the claims, reversed the holding that they were infringed. A
supposed conflict of this decision as to infringement with one by
the Circuit Court of Appeals of the Second Circuit, with respect to
the same patent, serves to bring the case here for review on writ
of certiorari.
The patent is a simple and, as we shall see, a narrow one. As
described in the specification, it relates to new and useful
improvements in incandescent electric lamp sockets, the principal
object of which is to provide a simple and effective automatic lock
or connection between the sleeve and the cap of such a socket.
Nothing new electrically or in the general form of the cap or
sleeve is claimed -- the invention relates solely to the method of
fastening the overlapping cap to the sleeve, or, as it is sometimes
called, the shell or casing.
The validity of the claims involved is conceded in argument,
and, having regard to the disclaimer with respect to Claims 2 and
3, which has been filed by the petitioner since the decision by the
circuit court of appeals, we regard the issue as now narrowed to
the infringement of the fourth claim.
The familiar incandescent lamp consists of a glass bulb attached
to a screw threaded base, adapted to be screwed into a properly
insulated block, through which the necessary electrical connections
are made and which is enclosed
Page 256 U. S. 670
by a cylindrical "sleeve" of sheet metal. In order to compete
the lamp, this detached sleeve supporting the bulb and enclosing
the insulated block must be fitted and securely fastened into the
usual cap, which is attached to the wall or fixture, for if the
fastening should become loose, the light might fail, or the bulb
fall, or a fire hazard be created. To invent a device by which the
sleeve and cap could be easily and securely attached to each other
and yet be readily detached when desired was the problem to which
the patentee addressed himself, and his solution of it is thus
described in the fourth claim of the patent:
"In a device of the class described, and in combination a pair
of members comprising a sheet metal sleeve having a slotted end,
and a sheet metal cap adapted to telescopically receive the slotted
end of said sleeve, one of said members being provided with a
recess, and the other having a correspondingly located
transverse slit and the wall on one side thereof displaced to
form a projection beveled or inclined toward said recessed
member and terminating abruptly
at said slit, whereby said
members are adapted to automatically interlock with a snap action
when telescopically applied to each other, and to be released by
manual compression of said slotted sleeve, substantially
as described."
To make the device thus described, it was only necessary to cut
two transverse slits, each about one-quarter of an inch in length,
in opposite sides of the flange of an ordinary cap, and to then,
with a punch or die, force outward the upper edges or walls of the
slits to the extent desired to create the necessary "recesses"
which must "terminate" at the lower, sharp edges of the slits. A
similar operation on a slotted sleeve would produce a similar
result, but, when viewed from the outer surface of the sleeve, the
recesses would become the projections of the quoted fourth claim.
When such sleeve is telescopically
Page 256 U. S. 671
applied to -- pushed or pressed into -- the cap, it is obvious
that, with the recesses in the cap and the projections in the
sleeve properly positioned and of a suitable size, when the
projections shall register with the recesses, the resiliency of the
metal will cause the two to engage with a snap action, and the
sharp lower edges of the slots in the cap will then prevent the cap
and sleeve from being separated by a longitudinal movement only,
until the sleeve shall be manually compressed to release the
projections from the recesses.
It is to be noted, for it will be of significance in the
interpretation of the claim involved, that it is required that the
projections on the sleeve shall be "beveled or inclined toward said
recessed member," and in the specification it is provided that the
projections shall be "beveled or inclined from the inner end of the
sleeve toward the outer end." With such construction, it would seem
plain, even without the exhibits, which show it to be true, that,
friction aside, projections so beveled or inclined could readily be
released by rotative movement from similarly shaped recesses
without compression of the sleeve.
It was admitted at the bar that sockets made as specified in the
patent in suit were never put upon the market, but the record shows
that, with a feature added which is covered by another patent owned
by petitioner, the socket met with large commercial success. This
other patent is No. 916,812, and was granted March 30, 1909, to the
patentee of the patent in suit and two others, on an application
filed July 18, 1904. Figures 8 and 9 from the drawings of this
patent, showing the cap and sleeve of the petitioner's socket as
manufactured by it, will aid in describing the additional
"improvement" which it made to the device of the patent in suit,
and will also be of service in comparing this device with what is
claimed to be the infringing socket of the respondent.
Page 256 U. S. 672
image:a
This patent is also for improvements in incandescent electric
light sockets, and contains 14 claims, of which only the terms of
the first need be noticed. It claims as new and useful
"a pair of tubular, sheet metal members, one adapted to
telescopically receive the other, having mutually abutting
cut-metal edges on the respective members [the slot 19 in the cap
and projection 20 in the sleeve], to
prevent relative rotative
movement, and automatically interlocking means for preventing
a telescopic movement of separation of one member from the other
[the recesses 17 in the cap and the projections 15 in the sleeve],
said means permitting, without manipulation thereof, the telescopic
application of the members to each other."
This language, with slight additions and omissions, not
significant, is repeated in Claims 3, 13, and 14.
This device for preventing "relative rotative movement" of the
cap on the sleeve is the feature which the petitioner added to the
socket of the patent in suit before putting it upon the market, and
it consists, as the figure,
supra, shows, in the open slot
(19) cut to the edge of the
Page 256 U. S. 673
flange of the cap, into which passes the projection on the
sleeve (20) when the two are "telescopically applied" to each
other. This projection (20) is formed by cutting two longitudinal
slits in the sleeve and then pressing outward the narrow strip of
metal between them. It is perfectly true, as stated in four of the
claims and as asserted with much emphasis in the specification,
that this added device effectively prevents any relative rotative
movement of the cap and sleeve upon each other.
Coming now to the construction of the respondent, which it is
claimed infringes the fourth claim of the patent in suit.
This (respondent's) socket has been manufactured since 1909,
under patent No. 927,344, and it may most readily be described by
reference to the following, Figure 3 of the drawing, which was a
part of the specification of the patent.
image:b
It will be seen from this drawing that, instead of outwardly
extending recesses in the flange of the cap, formed
Page 256 U. S. 674
by slits and displacing of the metal, such as are in the
petitioner's socket, respondent's cap has four inwardly projecting
lugs (19), each of which is a separate piece of metal riveted to
the flange. Each of these lugs is circular in outline, with a flat
inner end or face and presents abrupt shoulders on opposite sides.
In the upper edge of the sleeve are three bayonet slots of the
familiar form(14), so positioned that the studs on the cap may
enter them when the sleeve is slipped into the cap, but, when the
sleeve has been telescoped, or pushed, into the cap so that the
lugs have been pressed to the end or bottom of the longitudinal
part of the bayonet slots (14), rotation of the sleeve is obviously
necessary to bring them into the transverse parts of the slots, so
that the two members will be locked against longitudinal
separation. (No such rotative movement of the two members is
mentioned in the patent in suit, it is expressly provided against
in petitioner's second patent, and it is not possible in its
commercial socket.)
This rotative movement accomplishes a second result.
Reference to the figure,
supra, shows a longitudinal
slot in the sleeve which, in the key socket, affords a passage for
the key, but in the keyless socket is narrower, and serves only to
render the sleeve compressible. To the left of this slot in the
sleeve is cut a round hole (15) so positioned that, when three of
the lugs in the cap are brought by the rotative movement to the
ends of the transverse parts of the bayonet slots, the fourth end
will snap into the hole (15). This hole (15) is placed in such a
relative position that, when the three lugs enter the longitudinal
part of the bayonet slots, the fourth stud rides upon the metal
near the edge of the slot in the sleeve, and, to facilitate this
movement, the corner of the slot (16) is bent slightly inward.
Thus, the adjustment of the studs in the cap is practically a
universal adjustment between the cap and shell, so that, if any one
lug is in
Page 256 U. S. 675
position to enter any bayonet slot, two others will be in
position to enter the other bayonet slots, and the fourth will be
in a position to enter the hole(15) when the sleeve and cap have
been so pressed together that the (three) other studs have reached
the ends of the longitudinal part of the bayonet slots and the
rotation described of the one upon the other has been completed. A
slight compression of the sleeve suffices to release the members
when desired.
This description shows that the structural features of the two
sockets are strikingly different. Instead of slits and outwardly
extending recesses in the cap of the one, there are inwardly
extended studs riveted to the cap of the other. And instead of
slits and outward protections of the sleeve to lock by snap action
with recesses in the cap against longitudinal movement in the one,
there are the bayonet slots in the sleeve to lock with studs in the
cap of the other to accomplish the same result without snap action.
But these different constructions not only differ radically in
structural features, but they do not function in the same manner,
for locking against longitudinal movement in the one is by snap
action upon direct longitudinal thrust of the sleeve into the cap,
while the other requires first a longitudinal movement or thrust,
and then a rotative movement, without which it is entirely
ineffective, whereby it locks against longitudinal movement without
snap action.
But it is argued that the infringement lies especially in the
locking hole (15) in respondent's socket and the associated lug
which operate by snap action and afford a positive lock against
rotation of the two members on each other.
The sufficient answer to this is that the patent in suit makes
no suggestion of a lock against the rotative movement of the cap
and sleeve on each other, and contains no disclosure providing for
it, but, on the contrary, because
Page 256 U. S. 676
the beveled sides which are required by Claim 4 for the
projections on the sleeve permitted such movement, a subsequently
patented addition was added to prevent it. The petitioner cannot
read into the patent in suit the additional slot in the cap and the
additional projection on the sleeve of patentee's second patent,
and, without them, there is no lock against rotative movement in
the socket of the first patent to be infringed by the stud snapping
into the locking hole of the sleeve of respondent's socket.
This is sufficient to dispose of the case, but we also fully
agree with the circuit court of appeals that the prior art, the
file wrapper and the second patent to the same patentee, No.
916,812,
supra, require that the expressions in the fourth
claim "telescopically received" and "telescopically applied" must
be restricted to a direct longitudinal movement or thrust of the
sleeve into the cap, and that, for this reason, the construction of
respondent, requiring a rotary movement to render it effective,
does not infringe that of the petitioner.
In the application for the patent in suit this fourth claim,
originally the seventh, read as we have quoted it omitting the
words in italics. In this form, it was promptly rejected by the
Patent Office on reference to the Oetting patent, No. 642,825, and
to the Kenney patent, No. 712,686, and it is clear that the chief
concern of the applicant thereafter was to distinguish his
construction from that of Kenney, which is very similar to that of
respondent. The Kenney socket has lugs in the cap and bayonet slots
in the sleeve, to lock against longitudinal movement, as
respondent's socket has, and also slots with open ends and locking
holes similarly placed in the sleeve to lock against rotary
movement when the lugs in the cap engage with them. The chief
difference between the Kenney and respondent's socket is that, in
Kenney, the lug passes down the slot to a position opposite the
locking hole, and
Page 256 U. S. 677
then, with the rotary movement, mounts and rides over the narrow
strip of metal -- "the bridge" -- into the hole, while, in the
respondent's socket, the lugs having plain faces ride on the metal
near to the edge of the slot during the longitudinal movement, and
from that position pass into the locking holes with the rotative
movement.
When his application was rejected by the Patent Office on
reference to the Kenney patent thus described, the applicant,
without objection or appeal, amended his Claim 7 (numbering it 4)
by adding the words in italics, and, in his explanatory "remarks"
when submitting these amendments, it was said:
"Claim 4, originally 7, is now
drawn to a specific
structure having advantages not found in either of the
references cited. By transversely slitting the sheet metal shell
and displacing the wall on one side of said slit to form a beveled
or inclined projection, the parts are permitted to be applied to
each other
by simply inserting one within the other,
without manually compressing the inner member."
And again:
"Kenney's device is adapted to
unlock by simply rotating one
member upon another in the same manner that the parts are locked
together, no manual compression of the inner member being
necessary."
Thus, the patentee, in order to avoid infringing Kenney's
construction, voluntarily restricted himself to a "specific
structure" operative when the sleeve was "simply" inserted in the
cap, without suggesting any rotary movement whatever, but, on the
contrary, by his reference to Kenney as locking and unlocking by
"simply rotating one member upon the other," clearly implying that
no such rotary movement was necessary in the adjustment of his
socket. Having thus narrowed his claim against rotary movement in
order to obtain a patent, the patentee may not, by construction or
by resort to the doctrine of equivalents, give to the claim the
larger scope which it might have had without the amendments, which
amount to a
Page 256 U. S. 678
disclaimer of rotation as an operative feature of his device.
Shepard v. Carrigan, 116 U. S. 593,
116 U. S. 598;
Hubbell v. United States, 179 U. S.
77,
179 U. S.
80.
But that no rotary movement was implied in the use of
"telescopically received" and "telescopically applied" in the
patent in suit is further unmistakably shown by the frequent use of
the same or equivalent expressions in the specification and claims
of patentee's later patent, No. 916,812,
supra, in which
Claims 1, 3, 13, and 14 relate almost wholly to an improvement
which renders rotation of the members one upon the other impossible
and which petitioner added to the construction of the patent in
suit before putting the sockets upon the market. That the inventor
did not intend to claim, and that he certainly did not disclose,
that any such rotary movement was necessary in his socket as was
required to render the socket of the respondent effective is, we
think, for these reasons, so clear that it is not necessary to
consider the dictionary definitions of the words used, upon which
the circuit court of appeals, with sound reason, relied in reaching
this same conclusion.
For the reasons thus elaborated, we conclude that the socket of
the respondent does not infringe the fourth claim of the patent in
suit, because there is no claim made therein of a lock against
rotative movement of the cap and sleeve upon each other, and also
because the file-wrapper and the subsequent patent show that the
disclosure is, and was intended to be, limited to a construction
operative by direct longitudinal movement or thrust without such
rotative movement.
The contention, pressed strenuously upon our attention, that the
added open slot in the cap and projection on the sleeve provided
for in the second patent were devised simply to secure the
alignment of the projections and recesses of the first patent in
making telescopic application of the two members to each other is
not convincing
Page 256 U. S. 679
in the presence of the fact that Claims 1, 3, 13, and 14 of the
second patent are devoted almost wholly to claiming that this
improved construction is intended "to prevent relative rotative
movement" of one member upon the other, while only Claims 11 and 12
refer, quite incidentally, to what is now claimed to be the chief
function of the added parts -- that of a guide to the positioning
of the recesses and projections of the first patent with reference
to each other. Without a guide, the difficulty should not be very
great of aligning projections and recesses distant from each other
but a fraction of an inch when the edges of the cap and sleeve are
in contact. The constructions held by the circuit court of appeals
of the Second Circuit to infringe the patent in suit were so
essentially different from that of the respondent that we regard
discussion of them as quite unnecessary.
It results that the decree of the circuit court of appeals as to
Claims 1 and 4 must be
Affirmed.