Ex Parte Kohler et al

Board of Patent Appeals and Interferences

May 30, 2007

10047670 (B.P.A.I. May. 30, 2007)

The opinion in support of the decision being entered today was not written
for publication and is not binding precedent of the Board.

UNITED STATES PATENT AND TRADEMARK OFFICE
____________

BEFORE THE BOARD OF PATENT APPEALS
AND INTERFERENCES
____________

Ex parte GREGORY T. KOHLER and EDWARD A. ROBINSON
____________

Appeal 2006-3265
Application 10/047,670
Technology Center 3700
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Decided: May 30, 2007
____________

Before TERRY J. OWENS, MURRIEL E. CRAWFORD, and
JENNIFER D. BAHR, Administrative Patent Judges.

BAHR, Administrative Patent Judge.

DECISION ON APPEAL

STATEMENT OF THE CASE
Gregory T. Kohler and Edward A. Robinson (Appellants) appeal
under 35 U.S.C. § 134 from the Examiner’s decision rejecting claims 1, 5, 8,
11, and 13. Claims 2 and 15 stand withdrawn from consideration and claims
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3, 4, 6, 7, 9, 10, 12, and 14 stand objected to as depending from a rejected
claim. We have jurisdiction over this appeal under 35 U.S.C. § 6 (2002).
Appellants’ claimed invention is directed to a tank and cap assembly
for microchannel tubing in heat exchangers (Specification 1). The assembly
utilizes a cap having a slot therein through which the microchannel tubing is
inserted and a tank for receiving the cap therein (Specification 7 and 8). All
surfaces of the tank are free of braze clad or alloy, but the cap has braze clad
material on both its interior and exterior surfaces. Thus, when the tubing,
cap and tank are assembled as illustrated in Fig. 2 and subjected to a brazing
temperature, the braze cladding will flow to bond and seal the exterior
surface of the tubing with the cap within the slot and to seal the interface of
the cap with the tank. (Specification 9-10.) With Appellants’ assembly,
because braze clad or alloy is located only on the cap, in a region away from
the end of the tubing, braze clad or alloy is unlikely to migrate to the end of
the tubing and plug any of the ports or channels therein (Specification 13).
Independent claim 1 is illustrative of the claimed subject matter and reads as
follows:
1. A heat exchanger, comprising:
a flattened tube including a port extending to
an end of the tube;
a cap having a generally centrally located
slot sized to snugly receive said end and allow said
tube to pass fully through said slot, said cap having
a body in which said slot is formed and having an
exterior surface nominally concentric with said
slot, said exterior surface having a tube facing side
and an opposite side spaced therefrom, the
periphery of said cap at said tube facing side being
larger than the periphery at said opposite side; and
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a tank having a body with a cap receiving
end, a fluid receiving or discharging end spaced
from the cap receiving end, an interior cavity
opening to said cap receiving end, and a port
extending from said cavity at a location remote
from said cap receiving end to a location at or near
said receiving or discharging end, said cavity
having a stepped wall including a first section
sized to snugly receive said cap tube facing side, a
second section spaced from said first section and
sized to abut said tube end without blocking the
internal port thereat, and an intermediate section
between said first and second sections and sized to
abut said cap at a location between said tube facing
side and said opposite side when said tube facing
side is received in said first section;
said tank receiving said cap with said
intermediate section acting as a cap stop to limit
entry of said cap into said tank and said second
section acting as a tube stop limiting entry of said
tube end into said cavity.
The Examiner relies upon the following as evidence of
unpatentability:
Kocher US 2,134,719 Nov. 01, 1938
Brogan US 3,923,323 Dec. 02, 1975
Turner US 4,146,254 Mar. 27, 1979
Dalo US 4,945,983 Aug. 07, 1990
Ryan US 5,062,476 Nov. 05, 1991
Ando US 5,105,877 Apr. 21, 1992

Appeal 2006-3265
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Appellants seek review of the Examiner’s rejection of claims 1, 5, 8,
11, and 13 under 35 U.S.C. § 103(a) as being unpatentable over Kocher,
Brogan, or Turner in view of Dalo, Ryan, or Ando.1
The Examiner provides reasoning in support of the rejection in the
Answer (mailed March 27, 2006). Appellants present opposing arguments
in the Appeal Brief (filed January 25, 2006) and Reply Brief (filed May 22,
2006).

DISCUSSION
Appellants do not dispute that, if any of the primary references were
combined with any of the secondary references as proposed by the
Examiner, the subject matter of the rejected claims would result.
Accordingly, the issue before us in this appeal is whether it would have been
obvious to utilize the compression coupling technique of Kocher, Brogan, or
Turner to couple oval or flattened heat exchanger tubes, of the type
discussed by Dalo, Ryan, or Ando, to heat exchanger structure to arrive at
the subject matter of Appellants’ claims. Appellants contend that none of
the primary references is reasonably pertinent to the particular problem with
which Appellants were concerned, because they are directed toward
removable, round tube couplings, rather than to a brazed, and thus non-
removable, heat exchanger construction using a flat tube, and that there is

1 The Examiner’s application of so many prior art references in the
alternative hardly seems consistent with the instruction in Manual of Patent
Examining Procedure (MPEP) § 706.02 that “[p]rior art rejections should
ordinarily be confined strictly to the best available art …. Merely
cumulative rejections, i.e., those which would clearly fall if the primary
rejection were not sustained, should be avoided.”
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nothing in the primary references that would have logically commended
them to an inventor’s attention in considering the problem faced by
Appellants (Appeal Br. 4). Thus, according to Appellants, the Examiner has
improperly used hindsight in combining the references “simply to find the
specific structural description given for the tank and cap components in the
claims” (Appeal Br. 4). Appellants further contend the secondary references
Dalo, Ryan, and Ando teach away from their use in the coupling
arrangements of the primary references Kocher, Brogan, and Turner,
because the secondary references concern flattened tubes brazed to a header,
while the primary references teach removable couplings for round tubes
(Appeal Br. 5). Appellants additionally contend, in effect, that the structural
differences between flattened or oval tubes and round tubes are such that the
type of compression used in forming the couplings of Kocher, Brogan, and
Turner is not possible with the flat tubes of Dalo, Ryan, and Ando (Appeal
Br. 6).
Appellants are correct that none of the primary references Kocher,
Brogan, and Turner specifically addresses heat exchanger tubes. On the
other hand, there is nothing in Kocher, Brogan, and Turner that would have
discouraged one of ordinary skill in the art from utilizing the disclosed
coupling techniques to couple heat exchanger tubes to heat exchanger
structure. Further, while the Brogan technique, which involves rotation of
nut portion 14 of element 12 to urge sleeve portion 13 into constrictive
retention with the tube T (Brogan, col. 4, ll. 27-30; tube labelled “P” in the
only attached drawing), would not appear to be suitable for application to a
non-round, or flattened, tube, we find nothing in either of the coupling
techniques of Kocher and Turner which would seem to make it unsuitable
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for a flattened tube of the type discussed by Dalo, Ryan, and Ando, for
example. Appellants argue that the compression involved in the primary
references would not be possible with flattened tubes, which do not have the
same hoop strength and resilience as round tubes, because the flattened tubes
would begin to collapse under the pressure (Appeal Br. 6) but provide no
evidence that this is the case. An artisan must be presumed to know
something about the art apart from what the references disclose (see In re
Jacoby, 309 F.2d 513, 516, 135 USPQ 317, 319 (CCPA 1962)) and the
conclusion of obviousness may be made from “common knowledge and
common sense” of the person of ordinary skill in the art (see In re Bozek,
416 F.2d 1385, 1390, 163 USPQ 545, 549 (CCPA 1969)). Moreover, skill is
presumed on the part of those practicing in the art. See In re Sovish, 769
F.2d 738, 743, 226 USPQ 771, 774 (Fed. Cir. 1985). “A person of ordinary
skill is also a person of ordinary creativity, not an automaton.” KSR Int’l.
Co. v. Teleflex Inc., 127 S.Ct. 1727, 1742, 82 USPQ2d 1385, 1397 (2007).
Such a person would have understood that the deformation-causing
compression of Kocher’s technique (Kocher 2, col. 1, ll. 43-49; Fig. 1) and
the lock ring bite of Turner’s technique (Turner, col. 3, l. 68 to col. 4, l. 7)
must not exceed the force or deformation that the tube can withstand without
collapse or damage and would have been able to design the tube with the
necessary wall thickness and other structural supports to avoid collapse in a
coupling of the type taught by Kocher or Turner.
As for Appellants’ contention that the primary references are not
reasonably pertinent to the particular problem with which Appellants were
concerned, because they are not directed to flattened heat exchanger tubes
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with brazed connections and thus would not have commended themselves to
an inventor’s attention in considering the problem faced by Appellants,
[w]hen a work is available in one field of
endeavor, design incentives and other market
forces can prompt variations of it, either in the
same field or a different one. If a person of
ordinary skill can implement a predictable
variation, §103 likely bars its patentability. For the
same reason, if a technique has been used to
improve one device, and a person of ordinary skill
in the art would recognize that it would improve
similar devices in the same way, using the
technique is obvious unless its actual application is
beyond his or her skill.
KSR Int’l., 127 S.Ct. at 1740, 82 USPQ2d at 1396. We must ask whether
the improvement is more than the predictable use of prior art elements
according to their established functions. Id.
Further, in making a determination with regard to obviousness, we
should not limit ourselves to looking only at the problem Appellants were
trying to solve. The question is not whether the combination was obvious to
Appellants but whether it was obvious to a person with ordinary skill in the
art. Thus, “[u]nder the correct analysis, any need or problem known in the
field of endeavor at the time of invention and addressed by the patent can
provide a reason for combining the elements in the manner claimed.” KSR
Int’l., 127 S.Ct. at 1742, 82 USPQ2d at 1397.
In the present case, all of the references applied by the Examiner are
directed to tube couplings and, thus, by their very nature, present many of
the same problems and issues. Turner’s coupling arrangement offers the
advantage that it “will not only serve to couple metallic and non-metallic
substantially rigid tubing but also flexible tubing which can be used at
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elevated temperatures and pressures without slipping or becoming
disconnected from its coupler” (Turner, col. 1, ll. 30-35). Kocher’s coupling
arrangement is particularly adapted for mass production, is self-aligning and
devoid of cocking tendencies, and effects a particularly secure and fluid-
tight connection (Kocher 1, col. 1, ll. 32-36 and col. 2, l. 51 to col. 2, l. 1).
One skilled in the art at the time of Appellants’ invention would have
recognized that the advantages offered by the coupling arrangements of
Turner and Kocher would likewise be applicable to tube couplings in heat
exchangers, which need to be fluid-tight and may be subjected to elevated
temperatures and pressures. Moreover, as discussed above, the
modifications necessary to utilize the coupling arrangement of either Turner
or Kocher in a heat exchanger to couple flattened heat exchanger tubes to the
header or tank structure of the heat exchanger would have been well within
the skill of a person of ordinary skill in the art with predictable results and
with the flattened heat exchanger tubes of any of Dalo, Ryan, and Ando, the
heat exchanger structure, and the coupling connection of Turner or Kocher
performing their established functions.
We do not agree with Appellants that the secondary references Dalo,
Ryan, and Ando teach away from the combination of the flattened heat
exchanger tubes and the tube coupling arrangement of Kocher or Turner. “A
reference may be said to teach away when a person of ordinary skill, upon
[examining] the reference, would be discouraged from following the path set
out in the reference, or would be led in a direction divergent from the path
that was taken by the applicant.” In re Gurley, 27 F.3d 551, 553, 31
USPQ2d 1130, 1131 (Fed. Cir. 1994). Simply that there are differences
between two references is insufficient to establish that such references
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"teach away" from any combination thereof. See In re Beattie, 974 F.2d
1309, 1312-13, 24 USPQ2d 1040, 1042 (Fed. Cir. 1992). There is nothing
in Dalo, Ryan, or Ando that would have discouraged one of ordinary skill in
the art from utilizing a coupling of the type taught by Kocher or Turner,
neither of which involves brazing, in the heat exchanger to couple the heat
exchanger tubes to the tank structure. The couplings of Kocher and Turner
appear to be adapted to provide secure and fluid-tight connections and would
serve the same function in a heat exchanger environment. Appellants make
much of the fact that the Kocher and Turner couplings do not involve
brazing and are removable, while the couplings of Dalo, Ryan, and Ando are
brazed, and thus non-removable, but we note that Ryan, for example, brazes
the tubes 18 to the header plates 26, 28 (Ryan, col. 3, ll. 6-16; Fig. 2), but
does not braze the header plates 26, 28 to the tank 14. Rather, once the tubes
are seated against stop tabs 50, 52 of tank 14, the headers 26, 28 are fastened
in place by bending the extensions 60 of the tank 14, as illustrated in Fig. 2.
(Ryan, col. 4, ll. 34-39) Further, while the combination proposed by the
Examiner might change a heat exchanger structure from one wherein the
tubes are not removable from the tank structure to one wherein the tubes are
removable, there is no indication in the applied prior art that such a change
would be undesirable, unsuitable, or unpredictable, and Appellants have not
supplied any evidence that would so indicate.
For the above reasons, we conclude that Appellants have not
demonstrated that the Examiner erred in determining that it would have been
obvious to utilize either of the compression coupling techniques of Kocher
and Turner to couple oval or flattened heat exchanger tubes, of the type
discussed by Dalo, Ryan, or Ando, to heat exchanger structure and thus
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arrive at the subject matter of Appellants’ claims. Accordingly, the rejection
is sustained.
SUMMARY
The decision of the Examiner is affirmed.
No time period for taking any subsequent action in connection with
this appeal may be extended under 37 C.F.R. § 1.136(a). See 37 C.F.R.
§ 1.136(a)(1)(iv) (2006).
AFFIRMED

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