UNITED STATES PATENT AND TRADEMARK OFFICE
`____________
`
`BEFORE THE PATENT TRIAL AND APPEAL BOARD
`____________
`
`CATERPILLAR, INC.
`Caterpillar
`
`v.
`
`WIRTGEN AMERICA, INC.
`Patent Owner
`
`Case: IPR2017-02188
`Patent 9,656,530
`___________
`
`EXHIBIT 2008
`
`US 6,443,687 B1 Kaiser
`
`
`
`

`

`(12) United States Patent
`(10) Patent N0.:
`US 6,443,687 B1
`
`Kaiser
`(45) Date of Patent:
`Sep. 3, 2002
`
`US006443687B1
`
`(54) EXCAVATOR-HOIST
`
`(75)
`
`Inventor: Dietmar Kaiser, Sehaanwald (L1)
`
`(73) Assignee: KaiserAktiengesellschaft, Schaanwald
`(LI)
`
`( * ) Notice:
`
`Subject to any disclaimer, the term of this
`patent is extended or adjusted under 35
`U.S.C. 154(b) by 0 days.
`
`(21) Appl. No.: 09/543,807
`
`(22) Filed:
`
`Apr. 6, 2000
`
`Related U.S. Application Data
`
`(63) Continuation—impart of application No. 09/082,863, filed on
`May 21, 1998, now abandoned.
`
`(30)
`
`Foreign Application Priority Data
`
`May 23, 1997
`
`(AT)
`
`............................................... 897/97
`
`Int. Cl.7 ................................................... E02F 3/00
`(51)
`(52) U.S. Cl.
`...................... 414/685; 280/6156; 280/43;
`180/209
`
`(58) Field of Search ................................. 414/685, 687,
`414/680, 694; 212/302, 305, 180/209, 41,
`242, 906; 280/6153, 6.154, 6.155, 6.156,
`43, 43.17, 86.5
`
`(56)
`
`References Cited
`U.S. PATENT DOCUMENTS
`
`4,360,311 A
`4,392,541 A
`4,705,133 A
`5,498,021 A
`5,755,382 A
`
`11/1982 Dufour ....................... 414,687
`7/1983 Barchard .................... 180/209
`11/1987 Christenson .......... 180/209
`
`3/1996 Christenson ............. 180/209
`
`5/1998 Skotinkov ............ 286/6155 X
`
`*-X-**-X~
`
`* cited by examiner
`
`Primary Examiner—Donald W. Underwood
`(74) Attorney, Agent, or Firm—Sidley Austin Brown &
`Wood, LLP
`
`(57)
`
`ABSTRACT
`
`An excavator-hoist including a chassis for supporting an
`operator’s cab, a drive assembly, and a boom with a working
`tool supported at the free end of the boom, two pairs of
`projecting pivotable arms connected to opposite end sides of
`the chassis, respectively, for supporting at their free ends two
`pairs of wheels, with the arms, which support the front
`wheels having free end portions offset relative to respective
`remaining portions of the front wheel supporting arms in a
`vertical plane, with the front wheels being carried by the
`offset portions of the arms, and With respective piston-
`cylinder units, which are provided for pivoting the front
`wheel supporting arms in respective vertical planes, having
`one of their respective ends attached to the respective arms
`above pivot axes of the respective arms, and having another
`of their respective ends attached in respective regions of
`bottoms of the respective arms.
`
`3,279,622 A * 10/1966 Person ....................... 212/305
`
`3 Claims, 3 Drawing Sheets
`
`
`
`Wirtgen Exhibit 2008 IPR 2017-02188
`Wirtgen Exhibit 2008 IPR 2017-02188
`
`

`

`US. Patent
`
`Sep. 3, 2002
`
`Sheet 1 0f3
`
`US 6,443,687 B1
`
`Fig.1
`
`Wirtgen Exhibit 2008 IPR 2017-02188
`Wirtgen Exhibit 2008 IPR 2017-02188
`
`

`

`US. Patent
`
`Sep. 3, 2002
`
`Sheet 2 0f3
`
`US 6,443,687 B1
`
`
`
`Wirtgen Exhibit 2008 IPR 2017-02188
`
`

`

`US. Patent
`
`Sep. 3, 2002
`
`Sheet 3 0f3
`
`US 6,443,687 B1
`
`
`
`Wirtgen Exhibit 2008 IPR 2017-02188
`
`

`

`US 6,443,687 B1
`
`1
`EXCAVATOR-HOIST
`
`RELATED APPLICATIONS
`
`This application is a continuation-in-part of application
`Ser. No. 09/082,863 filed May 21, 1998, abandoned.
`
`BACKGROUND OF THE INVENTION
`
`1. Field of the Invention
`
`The present invention relates to an excavator-hoist includ-
`ing a chassis for supporting an operator’s cab, a drive
`assembly and a boom carrying at its free end a working tool,
`with the excavator-hoist further including two pairs of
`projecting arms connected to opposite end sides of the
`chassis, respectively, hydraulically operated piston—cylinder
`means for pivoting the arms in horizontal and vertical
`planes, and two pairs of motor-driven wheels supported on
`free ends of arms of respective pairs of arms, with the wheels
`of both pairs having approximately the same diameter, and
`the wheels of at least one pair being steerable.
`2. Description of the Prior Art
`A construction similar to that described above is in
`German Publication DE 42 19 803AI. It discloses a working
`tool assembled from a set of prefabricated separate units.
`The working tool is driven by a stepping or gear drive
`assembly. The undercarriage includes two connection
`devices for connecting two, sliding one beneath the other,
`pairs of hinge supports which are pre-assembled from a set
`of interchangeable, vertically and horizontally pivotable,
`wheeled or steady supports, so that the undercarriage is
`alternatively supported by two wheeled supports and two
`steady supports or by four wheeled supports. At that, at least
`two wheels of the pair of wheeled supports are driven and
`steered with wheel hub motors, with the remaining wheels
`being provided with parallel guiding means. Further units,
`which are connected with each other, form a superstructure,
`which is connected with a support housing by a pivot
`support, and a boom section secured on a pivot bracket. The
`object of the German reference is to provide means which
`would insure an assembly on a work cite of a working
`aggregate from a set of separate functional constructional
`units with relatively small expenses. The constructional unit
`themselves should have a construction which would insure,
`dependent on the use condition, formation, amplification or
`retooling of different excavators or movable cranes. E.g., the
`set described in the German reference permits to convert a
`simple walking excavator into a wheeled excavator to adapt
`it to improved driving conditions.
`An object of the present invention is an excavator-hoist
`with an improved mobility.
`Another object of the present invention is to provide an
`excavator-hoist having a compact construction and which
`can easily be moved.
`Afurther object of the present invention is an excavator-
`hoist with simple maintenance requirements so that it can be
`used for digging trenches and, in particular, water-carrying
`trenches.
`
`SUMMARY OF THE INVENTION
`
`These and other objects of the present invention, which
`will become apparent hereinafter, are achieved by providing
`an excavator-hoist of the type described above in which the
`arms, which support
`the steerable wheels, have front
`upwardly offset portions in a vertical plane, with the steer-
`able wheels being carried by offset portions of the steerable
`wheel supporting arms, and with respective piston-cylinder
`
`10
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`15
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`30
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`35
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`40
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`45
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`50
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`55
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`60
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`65
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`2
`units, which are provided for pivoting the steerable wheel
`supporting arms in respective vertical planes, having one of
`their respective ends attached to the respective arms above
`pivot axes of the respective arms, and having another of their
`respective ends attached in respective regions of bottoms of
`the respective arms. According to a particularly preferred
`embodiment of the present invention, the steerable wheel
`supporting arms have a box-shaped or downwardly-opening
`U-shaped profile, with each of the arms having a recess
`formed in a vertical longitudinal central plane of the arm for
`accommodating the arm-pivoting piston-cylinder unit. This
`measure permits to lift the bent-off arm rather high, with a
`sufficiently large free space still being available for a side-
`wise movement of the boom. At that, the piston-cylinder unit
`is adequate y protected.
`According to a further development of the present
`invention, tiere is provided a pair of L-shaped pivot levers
`for supporting the steerable wheel, with a horizontal leg of
`each pivot lever carrying an upright bolt an axis of which is
`located in a radial central plane of a respective steerable
`wheel, the Jolt being rotatably received in a bearing bore
`provided in a free end of a respective steerable wheel
`supporting arm and located approximately in a vertical
`longitudina central plane of the respective steerable wheel
`supporting arms. When the excavator-hoist moves along a
`muddy and wet bottom, the steerable wheel, together with
`the vertical y offset portions of the arm, form only a small
`surface which displaces along the muddy and wet bottom.
`On the other hand, when the wheels are positioned in a
`manner known from the state of the art, the wheel, together
`with their carriers located sidewise with respect
`to the
`supporting arms, present increased resistance surfaces which
`act as plowshares against
`the muddy mass when the
`excavator-hoist need to be moved.
`
`
`
`BRIEF DESCRIPTION OF THE DRAWINGS
`
`invention will
`The features and objects of the present
`become more apparent and the invention itself will be best
`understood from the following detailed description of the
`preferred embodiments when read with reference to the
`accompanying drawings, wherein:
`FIG. 1 shows a side view of an excavator-hoist according
`to the present invention;
`FIG. 2 shows a top view of an excavator-hoist according
`to the present invention, with the structure above the slewing
`ring removed for the sake of clarity;
`FIG. 3 shows a top view of an excavator arm with a
`steerable wheel of the excavator—hoist shown in FIG. 1, at an
`increased scale; and
`FIG. 4 shows a side view of an excavator arm with a
`steerable wheel of the excavator-hoist shown in FIG. 1, at an
`increased scale.
`
`DETAILED DESCRIPTION OF THE
`PREFERRED EMBODIMENT
`
`An excavator-hoist according to the present invention,
`which is shown in the drawings, includes a substantially
`rectangular chassis 1, a slewing ring 2 located above the
`chassis, and an operator’s cab 3 supported on the slewing
`ring 2. The inventive excavator-hoist further includes a drive
`assembly 4 and a multi-sectional boom 5 with a shovel 6
`which serves as a working tool. Apair of arms 7, which pivot
`in both horizontal and vertical planes are connected to the
`rear end side of the chassis 1. The pivotal movement of the
`arms 7 in the vertical plane about respective axes 22 is
`
`Wirtgen Exhibit 2008 IPR 2017-02188
`Wirtgen Exhibit 2008 IPR 2017-02188
`
`

`

`US 6,443,687 B1
`
`3
`effected with hydraulically operated piston-cylinder units
`having one of their ends supported on the chassis 1. The
`arms 7 carry, at their free ends, respective wheels 8 sup-
`ported on respective pivot levers 9. The pivotal movement of
`the arms 7 and the wheels 8 in the horizontal plane is
`effected with piston-cylinder units 76. The pivot levers 9,
`together with connecting rods 10 and arms 7 form two
`parallelograms which serve to insure a parallel movement of
`the wheels 8 during a horizontal pivotal movements of the
`arms 7. The wheels 8 are located sidewise of the respective
`arms 7, and drive motors are arranged in the hubs of the
`respective wheels 8. The wheels 8 have a diameter of 100 cm
`and more. The arms 7 are slightly bent outwardly, as can be
`seen in FIG. 2. This permits to keep the overall width of the
`excavator-hoist according to the present invention small
`despite large width B of the wheels 8.
`Another pair of arms 11 is attached to the front end of the
`chassis 1. The arms 11 are supported for pivotal movement
`about vertical axes 12 and horizontal axes 13. The arms 11
`
`are pivoted about their vertical axes 12 by respective piston-
`cylinder units 7b. For elfecting the pivotal movements of the
`arms 11 about their respective horizontal axes 13, there are
`provided respective, likewise hydraulically operated, piston-
`cylinder units 14 of which only one piston-cylinder unit 14
`is clearly shown and which serves for pivoting a respective
`arm 11 about a respective horizontal axis 3. Wheels 15 are
`provided at the free ends of the respective arms 11. The
`diameter of the wheels 15 correspond to that of the rear
`wheel 8. The wheels 15 are supported with L—shaped pivot
`levers 16, the upper horizontal legs of which carry respective
`upright bolts 17 the axes of which lie in radial central planes
`of the respective wheels 15. The bolts 17 are rotatably
`received in bearing bores provided at
`the free ends of
`respective arms 11. The bolt axes intersect the axes of the
`respective wheels 15. The bolts 17 are arranged approxi-
`mately in the vertical longitudinal central planes of the
`respective arms 11. The respective pivot
`levers 16 are
`connected with respective piston-cylinder units 18 arranged
`sidcwisc of rcspcctivc arms 11. Thc opposite ends of thc
`piston-cylinder units 18 are connected fixedly to the respec-
`tive arms 11. The piston-cylinder units 18 of the two arms
`11, which pivot respective wheels 15, are so connected with
`each other hydraulically that upon actuation of the piston-
`cylinder units 18, both wheels 15 pivot in the same direction
`about their respective axes defined by the bolts 17.
`The two arms 11 have their front portions 19 offset
`upwardly in a vertical plane, with the upwardly offset
`aortions 19 carrying respective pivot levers 16. Each arm 11,
`which has a box-shaped or downward-opening U-shaped
`3rofile, has at its side adjacent to the chassis 1, an upper
`recess 20. The piston-cylinder unit 14 has one of its end
`secured to the arm 11 above the horizontal pivotal axis 13.
`The piston-cylinder unit 14 is located in the recess 20 inside
`he arm 11, with the other end 21 of the piston-cylinder unit
`14 being located in the recess 20. Hydraulic drive motors are
`3rovided in the hubs of the wheels 15.
`
`
`
`The hydraulic motors of one side of the excavator-hoist
`and the hydraulic motors of the other side of the excavator-
`ioist, with reference to their vertical longitudinal central
`alanes, are serieusly connected. The hydraulic circuit for
`driving the wheels 8 and 15 can also include a four-way oil
`distributor, with the drive motors of the wheels 8 and 15
`3eing connected to the distributor, The arms 7 and 11 have
`substantially thc samc axial lengths.
`The four-wheel steerable excavator-hoist according to the
`oresent invention is extremely mobile and, therefore, can
`iandle all four sides. Despite its large wheels and protruding
`
`4
`arms, the excavator hoist according to the present invention
`has a very stable construction which is insured by providing
`the upward-bent arms 11, the steerable wheels 8 and 15, and
`by shielded arrangement of the piston-cylinder units 14. The
`excavator-hoist according to the present inventions is par-
`ticularly suitable for digging trenches due to its easy main-
`tenance and servicing.
`Though the present invention was shown and described
`with references to the preferred embodiments, various modi-
`fications thereof will be apparent to those skilled in the art
`and, therefore, it is not intended that the invention be limited
`to the disclosed embodiments or details thereof, and depar-
`ture can be made therefrom within the spirit and scope of the
`appended claims.
`What is claimed is:
`
`1. An excavator-hoist, comprising:
`a chassis;
`an operator’s cab and a drive assembly supported on the
`chassis;
`a boom secured at one end thereof to a front end side of
`the drive assembly and having an opposite free end;
`a working tool supported at the free end of the boom;
`a first pair of projecting arms connected to the front end
`side of the chassis and having each a free end portion
`offset in a vertical plane, upwardly relative to a remain-
`ing portion of a respective arm;
`a second pair of projecting arms connected to an opposite,
`rear end side of the chassis;
`first hydraulically operated piston-cylinder units for piv-
`oting the arms of the first pair of arms in horizontal and
`vertical planes, with the piston—cylinder units, which
`pivots the arms in respective vertical planes, having
`one of their respective ends attached to the respective
`arms above pivot axes of the respective arms, and
`having another of their respective ends attached in
`respective regions of bottoms of the respective arms;
`sccond hydraulically-opcratcd piston-cylinder units hav-
`ing first ends thereof secured to the chassis and having
`second ends thereof secured to respective arms of the
`second pair of arms for pivoting the arms in horizontal
`and vertical planes;
`a pair of front wheels supported on and carried by the
`upwardly offset free end portions of the arms of the first
`pair of arms; and
`a pair of rear wheels supported on free end portions of the
`arms of the second pair of arms and having a diameter
`approximately equal to a diameter of the front wheels.
`2. An excavator-hoist as set forth in claim 1, wherein the
`arms of the first pair of arms have one of a box-shaped and
`downward-facing U-shaped profile, and wherein each of the
`arms of the first pair of arms has a recess formed in a
`longitudinal central vertical plane in an upper surface
`thereof for accommodating a respective piston-cylinder unit
`of the first piston-cylinder units.
`3. An excavator-hoist as set forth in claim 1, further
`comprising a pair of L-shaped pivot levers for supporting the
`two front wheels, respectively, with a horizontal leg of each
`pivot lever carrying an upright bolt an axis of which is
`located in a radial central plane of a respective front wheel,
`the bolt being rotably received in a bearing bore provided in
`a free end of a respective front wheel supporting arm and
`located approximately in a vertical longitudinal central plane
`of the respective front wheel supporting arms.
`*
`*
`*
`*
`*
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`10
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`15
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`30
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`35
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`4O
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`45
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`50
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`55
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`60
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`65
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`Wirtgen Exhibit 2008 IPR 2017-02188
`Wirtgen Exhibit 2008 IPR 2017-02188
`
`