Case 1:17-cv-00770-JDW Document 305-4 Filed 02/02/24 Page 1 of 5 PageID #: 30375
`Case 1:17-cv-00770-JDW Document 305-4 Filed 02/02/24 Page 1 of 5 PagelD #: 30375
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`EXHIBIT 4
`EXHIBIT 4
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`WIRTGEN AMERICA, INC.
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`Plaintiff/Counterclaim-Defendant,
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`CATERPILLAR INC.
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`v.
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`Defendant/Counterclaim-Plaintiff.
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`Case 1:17-cv-00770-JDW Document 305-4 Filed 02/02/24 Page 2 of 5 PageID #: 30376
`HIGHLY CONFIDENTIAL – OUTSIDE ATTORNEYS’ EYES ONLY
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`IN THE UNITED STATES DISTRICT COURT
`FOR THE DISTRICT OF DELAWARE
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`C.A. No. 1:17-cv-00770-JDW
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`INITIAL EXPERT REPORT OF DR. JOHN H. LUMKES
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`Case 1:17-cv-00770-JDW Document 305-4 Filed 02/02/24 Page 3 of 5 PageID #: 30377
`HIGHLY CONFIDENTIAL – OUTSIDE ATTORNEYS’ EYES ONLY
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`coupling between the working cylinders in such a way that the left front wheel or caterpillar and
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`the right rear wheel or caterpillar are adjusted in height in the same direction and in the opposite
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`direction to the right front wheel or caterpillar and the left rear wheel or caterpillar.”
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`33.
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`Claim 29 depends from claim 26 and adds the limitation that “the machine has a
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`four sided stability pattern having a widest transverse dimension, transverse to the forward
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`direction of the chassis, which widest transverse dimension falls within a footprint of the working
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`roller or rotor.
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`3.
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`Advantages of the Floating Hydraulic Suspension
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`34.
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`In short, the ’309 patent is directed to a specific floating hydraulic suspension that
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`improves machine stability. The floating hydraulic suspension improves stability by provided a
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`diamond-shaped stability pattern because of the because of the hydraulically-coupled leg
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`cylinders. This stability pattern results in less motion as the machine travels over bumps or uneven
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`surfaces.
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`35.
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`This improved stability is helpful when traversing both sloped and flat surfaces
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`Road milling machines are relatively tall in comparison to their overall width, and a large portion
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`of the machine’s weight is located near the top of the machine. This can present stability issues
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`that can cause a machine to tip over on a sloped surface, which is not uncommon. CAT_00055857
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`at 5 (noting tip overs are “are not uncommon”); CAT_00055869; CAT_00055858. Tip overs are
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`not only dangerous, but are also costly because, due to the machine’s weight, large cranes are
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`typically needed to get the machine back upright. The floating hydraulic suspension is also
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`beneficial when traversing flat surfaces. For example, when milling on flat surface, the floating
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`hydraulic suspension minimizes movement of the machine frame and thus around the milling drum
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`when a track encounters a surface discontinuity, thereby improving the quality of the milled
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`8
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`Case 1:17-cv-00770-JDW Document 305-4 Filed 02/02/24 Page 4 of 5 PageID #: 30378
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`surface. Notably, even Caterpillar has acknowledged the stability advantages of the floating
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`hydraulic suspension’s diamond-shaped pattern. CAT_00055857 (PM6XX, PM8XX Stabilization
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`Presentation) at 10.
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`B.
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`36.
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`’530 Patent—Intelligent Leg Control
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`U.S. Patent No. 9,656,530, entitled “Automotive Construction Machine, As Well
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`As Lifting Column For A Construction Machine” issued May 23, 2017. The ’530 patent issued
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`form U.S. Application No. 14/683,273, filed April 10, 2015, and claims priority back to a German
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`application filed September 12, 2005. There are two named inventors, Peter Busley and Gunter
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`Tewes.
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`1.
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`Technical Background
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`37. Modern road milling machines typically include an operator’s platform, an engine,
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`height adjustable drive units, a rotating milling drum, and a conveyor. See WA-ITC_00225855-
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`5911. The operator’s platform is the cockpit of the road milling machine and is where an operator
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`controls the various aspects of the road milling process (usually by way of mechanical and
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`electrical controls and digital computers). The engine powers the various components of the road
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`milling machine. The drive units, including tracks or wheels, propel the machine forward or
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`backward over ground surfaces. The rotating milling drum, which is enclosed in a housing, has
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`spike-like cutting tools attached in spiral patterns around its surface. As the drum rotates, the
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`cutting tools grind the pavement into millings and propel the millings towards the center of the
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`milling drum. A conveyor near the center of the drum can be used to transport the collected
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`millings away from the milled surface, ejecting them from the housing into a nearby truck.
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`9
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`Case 1:17-cv-00770-JDW Document 305-4 Filed 02/02/24 Page 5 of 5 PageID #: 30379
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`XIII. Conclusion
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`This report contains my complete opinions as of today based on discovery provided by
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`Defendant. I reserve the right to amend, modify, or supplement this report in the even additional
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`discovery is provided by Defendant, including any expert opinions offered by Defendant.
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`Executed on May 18, 2023
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`John Lumkes, Ph.D.
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