Earth working – Automatic power control – Draft responsive
Reexamination Certificate
1999-12-15
2001-08-07
Novosad, Christopher J. (Department: 3671)
Earth working
Automatic power control
Draft responsive
C172S781000, C701S050000
Reexamination Certificate
active
06269885
ABSTRACT:
BACKGROUND OF THE INVENTION
The present invention relates to earth moving equipment, such as a motorized grader, and more particularly to systems controlling the position of a blade with respect to the ground on which the equipment travels.
During road construction, the earth is graded to a relatively smooth subsurface prior to laying asphalt or concrete which forms the surface of the road. The graded subsurface is produced by a machine that has a blade which scrapes the earth to a level desired for the subsurface.
A typical motorized road grader has the blade mounted between the front and rear wheels. Therefore, the front wheels ride on an uneven, ungraded surface ahead of the blade and the rear wheels ride on the smoother graded surface produced by the blade. As the front wheels move over undulations in the ungraded surface, the relative position of the blade changes, thereby producing an undulating graded surface. Thus the grader must make multiple passes over the area being graded until the surface has the desired degree of smoothness. Alternatively, the operator has to continuously make manual adjustments to the blade height, which requires a experienced operator and can produce operator fatigue.
SUMMARY OF THE INVENTION
The present invention provides a mechanism which compensates for movement of an earth mover blade so that a relatively smooth graded surface can be produced without making multiple grading passes over the same area. In addition the present mechanism does not require an experienced grader operator and eliminates fatigue resulting from continuous manual adjustment of blade height.
A machine, that produces a graded surface of earth, has front wheels, rear wheels and a frame to which the blade and wheels are attached. An apparatus is provided on the machine to control the position of the blade to produce a smoothly graded surface regardless of undulations of the ground on which the front wheels travel. That apparatus includes a sensor which detects an amount of movement of the frame with respect to either the rear wheels or the front wheels. A controller produces a compensation signal in response to the amount of movement detected by the sensor and a mechanism responds to the compensation signal by producing movement of the blade with respect to the earth.
In one embodiment of the invention, the mechanism moves the blade with respect to the frame. This version also may have another sensor that detects the position of the blade relative to the frame and provides a blade position signal. The controller produces the compensation signal also in response to the blade position signal.
In a different embodiment, the mechanism moves the front wheels with respect to the frame. Another sensor may be provided to detect the position of the front wheels relative to the frame and provide a wheel position signal. The compensation signal also is used by the controller to operate the mechanism.
REFERENCES:
patent: 3516497 (1970-06-01), Waterson
patent: 4045893 (1977-09-01), Feinzilber et al.
patent: 4085805 (1978-04-01), Hawkins et al.
patent: 4807131 (1989-02-01), Clegg
patent: 5647439 (1997-07-01), Burdick et al.
patent: 5764511 (1998-06-01), Henderson
patent: 5819190 (1998-10-01), Nakagami et al.
patent: 5905968 (1999-05-01), Staub et al.
patent: 5935183 (1999-08-01), Sahm et al.
patent: 6028524 (2000-02-01), Hartman et al.
patent: 6082927 (2000-07-01), Dahlinger et al.
patent: 6089327 (2000-07-01), Kimura et al.
patent: 6112145 (2000-08-01), Zachman
patent: 6128563 (2000-10-01), Muraro
patent: 6129156 (2000-10-01), Boast et al.
Barber Dennis R.
Mullins Patrick T
Haas George E.
HUSCO International Inc.
Novosad Christopher J.
Quarles & Brady LLP
LandOfFree
Blade height control system for a motorized grader does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Blade height control system for a motorized grader, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Blade height control system for a motorized grader will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-2441877