Ex Parte Hsu et al

Patent Trial and Appeal Board

Oct 22, 2018

13298727 (P.T.A.B. Oct. 22, 2018)

UNITED STA TES p A TENT AND TRADEMARK OFFICE
APPLICATION NO. FILING DATE
13/298,727 11/17/2011
279 7590
IP Docket
Clark Hill PLC
130 East Randolph Street
Suite 3900
Chicago, IL 60601
10/24/2018
FIRST NAMED INVENTOR
Christopher Hsu
UNITED STATES DEPARTMENT OF COMMERCE
United States Patent and Trademark Office
Address: COMMISSIONER FOR PATENTS
P.O. Box 1450
Alexandria, Virginia 22313-1450
www .uspto.gov
ATTORNEY DOCKET NO. CONFIRMATION NO.
24500/163042/21 6836
EXAMINER
PAIK, SANG YEOP
ART UNIT PAPER NUMBER
3761
NOTIFICATION DATE DELIVERY MODE
10/24/2018 ELECTRONIC
Please find below and/or attached an Office communication concerning this application or proceeding.
The time period for reply, if any, is set in the attached communication.
Notice of the Office communication was sent electronically on above-indicated "Notification Date" to the
following e-mail address(es):
IPDocket@clarkhill.com
PTOL-90A (Rev. 04/07)
UNITED STATES PATENT AND TRADEMARK OFFICE
BEFORE THE PATENT TRIAL AND APPEAL BOARD
Ex parte CHRISTOPHER HSU,
JEFFREY J. KRUPP, and JAMES W. MUMAW1
Appeal2018-001372
Application 13/298,727
Technology Center 3700
Before JAMES P. CALVE, NATHAN A. ENGELS, and
ALYSSA A. FINAMORE, Administrative Patent Judges.
CAL VE, Administrative Patent Judge.
DECISION ON APPEAL
STATEMENT OF THE CASE
Appellants appeal under 35 U.S.C. § 134(a) from the Office Action
rejecting claims 1-19, 21-32, and 34--39. Appeal Br. 3. We have
jurisdiction under 35 U.S.C. § 6(b ).
We AFFIRM-IN-PART.
1 Nelson Stud Welding, Inc. is identified as the real party in interest. Appeal
Br. 4.
Appeal2018-001372
Application 13/298,727
CLAIMED SUBJECT MATTER
Claims 1, 29, 30, 34, and 38 are independent. Claim 1 is reproduced
below.
1. A drawn arc fastener welding process for welding a metal
work fastener carried by welding tool to a work piece, the
process comprising the steps of:
contacting the work piece against the work piece;
energizing a pilot current;
lifting the fastener from the work piece and drawing a
pilot arc;
increasing the pilot current in order to form a main arc
for a predetermined duration thereby forming a weld pool in the
work piece and weld pool on the bottom of the fastener;
short circuiting the fastener to the weld pool;
cyclically redrawing an arc and short circuiting the
fastener to the weld pool at least one additional cycle;
dynamically sensing an arc voltage and calculating a time
derivative signal of the arc voltage for each drawn arc and short
circuit of the cycle in order to control the position of the
fastener relative to the weld pool during lifting until a positive
lift threshold of the time derivative of the arc voltage is reached
and alternatively controlling the plunging until a negative
plunge threshold of the time derivative of the arc voltage is
reached; and
lifting the fastener away from the weld pool to said
position until the positive lift threshold of the time derivative of
the arc voltage is reached;
plunging the fastener toward the work piece from said
position forming a weld until the negative plunge threshold of
the time derivative of the arc voltage is reached.
Appeal Br. 25 (Claims App.).
REJECTIONS
Claims 34 and 35 are rejected under 35 U.S.C. § 112, second
paragraph as being indefinite.
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Appeal2018-001372
Application 13/298,727
Claims 34, 35, and 38 are rejected under 35 U.S.C. § I02(b) as
anticipated by Hsu (US 2010/0230389 Al, pub. Sept. 16, 2010).
Claims 1-5, 7, 10-15, 18, 24, 26, 27, and 29-31 are rejected under 35
U.S.C. § I03(a) as unpatentable over Hsu, Schmitt (US 6,815,631 B2, iss.
Nov. 9, 2004), Risbeck (US 4,441,012, iss Apr. 3, 1984) or Huismann
(US 7,102,099 B2, iss. Sept. 5, 2006), and Aimi (US 2010/0224608 Al, pub.
Sept. 9, 2010) or Stava (US 6,025,573, iss. Feb. 15, 2000).
Claim 6 is rejected under 35 U.S.C. § I03(a) as unpatentable over
Hsu, Schmitt, Risbeck or Huismann, Aimi or Stava, and Jenkins (US
4,085,307, iss. Apr. 18, 1978).
Claims 8 and 16 are rejected under 35 U.S.C. § I03(a) as unpatentable
over Hsu, Schmitt, Risbeck or Huismann, Aimi or Stava, and Liu (US
2012/0234803 Al, pub. Sept. 20, 2012).
Claim 9 is rejected under 35 U.S.C. § I03(a) as unpatentable over
Hsu, Schmitt, Risbeck or Huismann, Aimi or Stava, Soenen (US 2011/
0187566 Al, pub. Aug. 4, 2011), and Zannoth (US 2010/0079186 Al, pub.
Apr. 1, 2010).
Claim 17 is rejected under 35 U.S.C. § I03(a) as unpatentable over
Hsu, Schmitt, Risbeck or Huismann, Aimi or Stava, and Raycher (US
5,070,226, iss. Dec. 3, 1991).
Claims 19, 21-23, 36, 37, and 39 are rejected under 35 U.S.C.
§ I03(a) as unpatentable over Hsu, Schmitt, Risbeck or Huismann, Aimi or
Stava, Albrecht (US 7,452,171 B2, iss. Nov. 18, 2008), and Nelson (US
2,268,416, iss. Dec. 30, 1941).
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Appeal2018-001372
Application 13/298,727
Claim 25 is rejected under 35 U.S.C. § I03(a) as unpatentable over
Hsu, Schmitt, Risbeck or Huismann, Aimi or Stava, and Kimura
(EP O 658 396 Al, pub. June 21, 1995).
Claim 28 is rejected under 35 U.S.C. § I03(a) as unpatentable over
Hsu, Schmitt, Risbeck or Huismann, Aimi or Stava, and Kon (US 4,681,998,
iss. July 21, 1987).
Claim 32 is rejected under 35 U.S.C. § I03(a) as unpatentable over
Hsu, Schmitt, Risbeck or Huismann, Aimi or Stava, and Liu.
ANALYSIS
Claims 34 and 35 as being indefinite
The Examiner determines claim 34 is indefinite because it lacks
antecedent basis for "the second time derivative." Non-Final Act. 2. The
Examiner also finds that there is no context for "a second time derivative"
when "a first time derivative" is not claimed. Id.; Ans. 2. Appellants do not
present any arguments for this rejection. Thus, we summarily sustain the
rejection of claim 34 and its dependent claim 35 for indefiniteness.
Claims 34, 35, and 38 Anticipated By Hsu
The Examiner finds that Hsu teaches a welding process that senses arc
voltage and controls the lifting and plunging of a fastener relative to a work
piece as a function of a time derivate of the arc voltage over time as shown
in Figure 4. Non-Final Act. 3. The Examiner reasons that the arc voltage
and current are sensed for suitable conditions for the fastener to be plunged
into the work piece so the position of the fastener is deemed to be controlled
by the arc voltage (provided by the arc current), which is controlled over a
period of time. Ans. 10. The Examiner finds that Figure 4 of Hsu shows the
current, voltage, and fastener position as a function of time. Id.
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Appeal2018-001372
Application 131298,727
Appellants argue that Hsu uses a predetermined time recorded during
a calibration step to control plunging of the fastener toward the work piece
rather than the claimed time derivative of voltage. Br. 8-9 (citing Hsu ,r 35).
Appellants also argue that Figure 4 of Hsu is a diagram of current, voltage,
and fastener position over time rather than a plot of time derivatives of arc
voltages, let alone using such a time derivative to control the position of the
fastener relative to the work piece as claimed. Id. at 9-10. We agree.
Appellants disclose that their "filtered derivative method makes it
possible to measure the arc voltage at the output terminals of the welding
power source with reliable detection of a legitimate arc to short transition."
Spec. ,r 21. "[T]he control monitors for a positive derivative threshold value
of the arc voltage over time (dvldt), for example 100 volts per millisecond,
signifying that [liquid] bridge 48 [between fastener 10 and work piece 30]
has been broken and stops the lift immediately maintaining the lift position
dynamically." Id. ,r 23. As a result, "[d]etection of the formation of the arc
may be achieved when the derivative value is greater than 100 volts per
millisecond." Id. ,r 26. To control the plunging of fastener 10, the control
determines "[ w ]hen the filtered derivative value reaches a predetermined
threshold level such as, for example, below -100 volts per millisecond" so
that the current can be reduced to reduce splatter prior to plunging. Id.
Therefore, Appellants propose an arc welding process using a drawn
fastener as an electrode that is raised and lowered relative to a workpiece.
To control the lifting and plunging of the fastener, Appellants measure the
change in arc voltage over time, i.e., "the time derivative of the arc voltage"
(dvldt). Id. ,r 23. Appellants control the fastener movement when the time
derivative reaches a threshold value (slope), e.g., -100 vims or +100 vims.
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Appeal2018-001372
Application 13/298,727
In contrast to the drawn arc welding process of independent claims 34
and 38, Hsu controls the plunging of the fastener toward the workpiece "at a
time determined by the recorded time in step d)" which involves calibration
by starting and stopping the timer when the fastener contacts the work piece
and when it separates from the workpiece and shorts. Hsu ,r 3 5 ( emphasis
added). Hsu also teaches that "the calibration of the welding tool defines the
time for the fastener to be plunged into the molten weld pool" and "[t]his
time is recorded and then utilized by the controller such that the plunging
operation is performed to maintain the preprogramming value of the time of
the main weld current." Id. Hsu then controls the current until a set point in
time and lowers current to a predetermined plunge current before moving the
fastener from its lifted position to its fully plunged position. Id. ,r 29.
Even if Hsu senses voltage and provides current suitable for plunging
the fastener into the workpiece, the Examiner's finding that "the position of
the fastener is thus deemed controlled by the arc voltage (provided by the arc
current) that is controlled over a period of time" (Ans. 10) does not explain
how the fastener movement is controlled based on a time derivative of arc
voltage. The Examiner has not explained where Hsu teaches to measure arc
voltage and then control the movement of the fastener based on the change
in the arc voltage over time (i.e., the time derivative of the arc voltage).
Figure 4 of Hsu shows a main current reduced to 200 amps before the
fastener is plunged into the workpiece to minimize splattering. Id. ,r 29. In
Figure 4, voltage drops from about 25 volts to about 15 volts; however, the
fastener position does not change until after the voltage stabilizes at that
level for a short time. Then, the fastener starts to plunge as the voltage also
decreases. Thus, we do not sustain the rejection of claims 34, 35, and 38.
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Appeal2018-001372
Application 13/298,727
Claims 1-5, 7, 10---15, 18, 24, 26, 27, and 29-31
Unpatentable over Hsu, Schmitt, Risbeck or Huismann,
and Aimi or Stava
Independent claims 1, 29, and 30 each include a limitation directed to
controlling the lifting and plunging of the fastener when the positive lift and
the negative plunge thresholds of the time derivative of the arc voltage are
reached. See Br. 25, 29-30 (Claims App.). We agree with Appellants that
Hsu does not disclose this feature in Figure 4 or the written description for
the reasons discussed above for claims 34 and 38. Br. 14.
We also agree with Appellants that Figure 6 of Risbeck does not teach
this feature. Id. at 15. We agree with the Examiner that Figure 6 of Risbeck
discloses changes in voltage, i.e., voltage increases and voltage drops. Non-
Final Act. 4--5; Ans. 11. However, Risbeck advances and retracts filler wire
18 using cam 36 and synchronizes the current levels to coincide with contact
between filler wire 18 and weld pool 24. Risbeck, 5: 1-10, 5:50-67, Figs. 1-
3. Because contact between filler wire 18 and weld pool 24 can be detected
when the voltage level approaches zero, voltage changes from one level to
another level are used to set the timing of peak current pulses. Id. at 6:42-
54, Fig. 6. However, we find no teaching in Risbeck to use a time derivative
of the voltage to control the position of electrode 12 or filler wire 18.
The Examiner's finding that Figures 6 and 8 of Huismann show a
down/negative time derivative of the arc voltage when the wire is plunging
and an up/positive time derivative occurring when a short is about to initiate
another arc does not explain where Huismann controls lifting or plunging of
the wire based on a time derivative of voltage. Non-Final Act. 5; Ans. 11.
Instead, Huismann teaches to reverse wire feed speed when the arc voltage
level (versus a time derivative of voltage) drops below a threshold. Br. 16.
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Appeal2018-001372
Application 13/298,727
Transitions between the arc and short circuit states are caused to occur
by controlling the wire movement, and the current is coordinated with these
transitions to reduce spatter and undesirable features. Huismann, 3:50-61;
see Br. 17. Such "mechanical control of the process allows the process to
better have a desired arc length." Huismann, 3: 64--65. Figure 6 illustrates a
desired arc current waveform in relation to voltage changes. A low current
segment is entered before a short forms ( as indicated by a voltage level drop
to near zero) to enhance a smooth transition to the short circuit state. Id. at
7:43--48. Figure 8 of Huismann illustrates the forward and reverse wire feed
speeds of a process cycle. Huismann teaches that a voltage drop below a
threshold level indicates a short, whereupon the wire feed speed is reversed.
Id. at 8:28-32. The reverse wire feed speed is maintained after an arc forms
based on the length of time required to provide the desired arc length. Id. at
8:33-39. Neither Figure 6 nor Figure 8 shows control of a fastener relative
to a workpiece based on a time derivative of arc voltage (i.e., on the amount
of change in voltage levels over time, dv/dt), however. Br. 17. Thus, we do
not sustain the rejection of claims 1-5, 7, 10-15, 18, 24, 26, 27, and 29-31.
Claims 6, 8, 9, 16, 17, 19, 21-23, 25, 28, 32, 36, 37, and 39
The Examiner's reliance on Jenkins, Liu, Soenen, Zannoth, Raycher,
Albrecht, Nelson, Kimura, or Kon to teach features recited in claims 6, 8, 9,
16, 17, 19, 21-23, 25, 28, 32, 36, 37, and 39 does not overcome the
deficiencies of Hsu, Risbeck, and Huismann discussed above as to claim 1
from which these claims depend directly or indirectly. Non-Final Act. 6-10;
Ans. 13; Br. 19-23. Thus, we do not sustain the rejections of these claims.
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Appeal2018-001372
Application 13/298,727
DECISION
We affirm the rejection of claims 34, 35, and 38 for indefiniteness.
We reverse the prior art rejections of claims 1-19, 21-32, and 34--39.
No time period for taking any subsequent action in connection with
this appeal may be extended under 37 C.F.R. § 1.136(a)(l)(iv).
AFFIRMED-IN-PART
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