Earth working – Automatic power control – Land leveller type
Reexamination Certificate
1999-08-09
2001-09-11
Novosad, Christopher J. (Department: 3671)
Earth working
Automatic power control
Land leveller type
C172S779000, C172S821000, C172S812000, C701S050000
Reexamination Certificate
active
06286606
ABSTRACT:
TECHNICAL FIELD
The present invention relates generally to manual and automatic positioning of a work implement and, more particularly, to a method and apparatus for controlling modes of operation of a work implement of a work machine.
BACKGROUND ART
Work machines, such as motor graders, dozers, compactors, pavers, profilers and scrapers, are used for geographic surface altering operations. The machines include a work implement, such as a surface altering blade, that is movably connected to a frame of the machine by one or more hydraulic motors or cylinders, or the work implement may be fixed to the machine frame. The position of the blade relative to the work surface must be accurately controlled to achieve the desired surface altering cut.
In motor graders, for example, the surface altering blade is movably connected to the grader frame by a pair of independently actuatable hydraulic lift cylinders that are mounted on either side of the machine frame. The hydraulic lift cylinders are independently extensible and retractable to move corresponding sides of the blade relative to the machine frame. Each side of the blade may be set by the operator to operate in either a “manual” or “automatic” mode of operation. In either mode, each side of blade is also assignable by the operator to operate in a “grade sensor”, “slope sensor” or “down force” mode of operation. Control for each side of the blade is independently assignable to one of the “grade sensor”, “slope sensor” and “down force” modes of operation such that both sides may be assigned to “grade sensor” or “down force” modes, or one side assigned to “grade sensor” or “down force” mode while the other side is assigned to the “slope sensor” mode.
When “grade sensor” (or “down force”) and “slope sensor” modes are assigned simultaneously to the opposite sides of the blade, the leading end or toe of the blade is generally assigned to the “grade sensor” mode, and the trailing or heel of the blade is assigned to the “slope sensor” mode. In “automatic” mode, a grade sensor maintains the grade sensor controlled side of the blade at a preselected position relative to a grade reference point. The elevation of the slope controlled side of the blade is controlled by a programmed cross slope value selected by the operator and stored in an implement controller that controls the “grade sensor”, “down force” and “slope sensor” modes of operation.
During a grading operation in one direction, the operator rotates the blade to a desired grading angle relative to the machine frame and may assign the “grade sensor” (or “down force”) and “slope sensor” control modes to the opposite sides of the blade. On a return grading pass in the opposite direction, the operator must rotate the blade to a mirror angle, and manually switch the “grade sensor” (or “down force”) and “slope sensor” modes assigned to the opposite sides of the blade. To achieve the switch of the control modes, the operator must manually actuate control switches that are located in the cab.
During the motor grader reconfiguration process for the return grading pass, the operator may improperly reassign the control modes of operation to the blade which may result in the wrong cross slope cut. Moreover, the manual reconfiguration process required for grading in opposite directions reduces the operator's accuracy and efficiency.
The present invention is directed to overcoming one or more of the problems as set forth above.
DISCLOSURE OF THE INVENTION
The present invention overcomes the foregoing and other shortcomings and drawbacks of work implement positioning and methods heretofore known. While the invention will be described in connection with certain embodiments, it will be understood that the invention is not limited to these embodiments. On the contrary, the invention includes all alternatives, modifications and equivalents as may be included within the spirit and scope of the present invention.
In one aspect of the invention, an apparatus for controlling a work implement of a work machine in simultaneous first and second control modes of operation is provided. An implement controller is operable to assign the first and second control modes of operation to the work implement. Positioning mechanisms may be connected to each side of the work implement for altering the position of each side of the work implement.
One of the positioning mechanisms may be operable to move one side of the work implement to a first position, and the other positioning mechanism may be operable to move the other side of the work implement to a second position. A sensor is associated with the work implement and coupled to the implement controller for applying a signal to the implement controller indicating position of the work implement. The implement controller is operable to change the control mode assignments to the work implement upon determining a predetermined movement of the work implement as indicated by the sensor, such as a predetermined rotation of the work implement. Upon determining a predetermined movement of the work implement, the implement controller may be operable to reverse the first and second control mode assignments to the work implement, and may also be operable to reverse the first and second positions of the work implement as well.
In another aspect of the invention, a drive mechanism may be operatively connected to the work implement for moving the work implement between a first rotational position and a second rotational position under control of the implement controller. A manually actuatable device is electrically coupled to the implement controller. The implement controller is operable to reverse the control assignments to, and the rotational position of, the work implement upon actuation of the manually actuatable device.
In yet another aspect of the invention, a method for controlling a work implement of a work machine in simultaneous first and second control modes of operation is provided. First and second automatic control modes are assigned to the work implement. Movement of the work implement is sensed and, upon a predetermined movement of the work implement as detected during the sensing step, the first and second control modes assigned to the work implement are reversed.
REFERENCES:
patent: 4136508 (1979-01-01), Coleman et al.
patent: 4185700 (1980-01-01), Atherton et al.
patent: 4221266 (1980-09-01), Fardal
patent: 4286386 (1981-09-01), Long
patent: 4288196 (1981-09-01), Sutton
patent: 4646620 (1987-03-01), Buchl
patent: 4733310 (1988-03-01), Kapp et al.
patent: 4733355 (1988-03-01), Davidson et al.
patent: 4744218 (1988-05-01), Edwards et al.
patent: 4912643 (1990-03-01), Beirxe
patent: 4918608 (1990-04-01), Middleton et al.
patent: 4934463 (1990-06-01), Ishida et al.
patent: 4955437 (1990-09-01), Bohman
patent: 5065326 (1991-11-01), Sahm
patent: 5078215 (1992-01-01), Nau
patent: 5170342 (1992-12-01), Nakamura et al.
patent: 5274557 (1993-12-01), Moriya et al.
patent: 5327345 (1994-07-01), Nielsen et al.
patent: 5356259 (1994-10-01), Hanamoto et al.
patent: 5430651 (1995-07-01), Nielsen et al.
patent: 5499684 (1996-03-01), Stratton
patent: 5551518 (1996-09-01), Stratton
patent: 5631658 (1997-05-01), Gudat et al.
patent: 5647439 (1997-07-01), Burdick et al.
patent: 5667020 (1997-09-01), Palmer et al.
patent: 5735352 (1998-04-01), Henderson et al.
patent: 5894894 (1999-04-01), Szymczak
patent: 5905986 (1999-05-01), Rohrbaugh et al.
patent: 5947225 (1999-09-01), Kawakami et al.
patent: 5951612 (1999-09-01), Sahm
patent: 5987371 (1999-11-01), Bailey et al.
patent: 1390066 (1975-04-01), None
patent: 57-071939 (1982-05-01), None
patent: 58-164835 (1983-09-01), None
patent: 59-102023 (1984-06-01), None
Cheek John J.
Krieg Randy K.
Caterpillar Inc.
Cheek John J.
Derry Thomas L.
Novosad Christopher J.
Wood Herron & Evans LLP
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