US3791452A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Control system for road grader
Assignee: Grad Line Inc
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Filing: 1971-03-17
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Granted: 1974-02-12
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Expires: 1991-03-17
Abstract
Abstract A control system for a road grader adapted to maintain the working edge of the grader blade in a preset datum plane so as to establish a uniform graded condition of the surface worked by the blade, regardless of the inclination assumed by the motor grader or the relative angular position of the blade itself. The system includes grade sensor means mounted adjacent one end of the blade to follow a pre-selected grade datum, slope sensing means mounted in fixed relation with the blade for keeping the blade at a predetermined slope with rotation sensing means mounted on the blade supporting ring or circle to detect the relative angular position of the blade. The rotation sensing means provides a correction signal for maintaining the slope angle of the blade at a value which will keep the ''''cross slope'''' of the surface established at a predetermined value regardless of the rotary position of the blade relative to the direction of travel.
Inventors
- 👤 G Long
- 👤 F Johnson
- 👤 D Reese
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-25 17:01
CPC Classifications
E; E02; E02F; E02F3/00; E02F3/04; E02F3/76; E02F3/80; E02F3/84; E02F3/844; E02F3/845
Claims Analysis
Total Claims: 10
Claim 1
Independent Claim
312 words
In a traveling machine having a movable frame, an elongated surface working element supported by said frame, and adjustment means on the machine to independently adjust the elevation of each end of the element and its rotational position relative to said frame, said machine being adapted to establish a planar surface having a predetermined cross shape angle defined as the angle between the surface established and a horizontal plane, said angle being located in a vertical plane perpendicular to the direction of travel of the machine, a control system comprising in combination; grade sensing and control means operatively associated with said working element and said adjustment means for sensing a preset grade datum and maintaining one end of said working element at a predetermined elevation related to said grade datum during travel of the machine, a slope sensing unit operatively associated with said working element and having means to produce a slope signal proportional to the degree of inclination of said element relative to a horizontal plane, input slope signal means providing a constant signal of predetermined value corresponding to the desired slope angle of the working element, slope signal mixing means adapted to produce a difference signal representing the difference between said input slope signal and said sensed slope signal, slope control means responsive to said difference signal for controlling said adjustment means for correcting the elevation of the other end of said working element to maintain said desired slope angle, and position sensing means operatively associated with said working element and responsive to the rotary position of said working element relative to the machine frame for modifying the given slope setting of said input slope signal means in relation to the rotary position of said working element, whereby said element establishes a planar surface having said predetermined cross slope regardless of the rotary position thereof during travel of said machine.
Claim 2
Dependent Claim
312 words
In a traveling machine having a movable frame, an elongated surface working element supported by said frame, and adjustment means on the machine to independently adjust the elevation of each end of the element and its rotational position relative to said frame, said machine being adapted to establish a planar surface having a predetermined cross shape angle defined as the angle between the surface established and a horizontal plane, said angle being located in a vertical plane perpendicular to the direction of travel of the machine, a control system comprising in combination; grade sensing and control means operatively associated with said working element and said adjustment means for sensing a preset grade datum and maintaining one end of said working element at a predetermined elevation related to said grade datum during travel of the machine, a slope sensing unit operatively associated with said working element and having means to produce a slope signal proportional to the degree of inclination of said element relative to a horizontal plane, input slope signal means providing a constant signal of predetermined value corresponding to the desired slope angle of the working element, slope signal mixing means adapted to produce a difference signal representing the difference between said input slope signal and said sensed slope signal, slope control means responsive to said difference signal for controlling said adjustment means for correcting the elevation of the other end of said working element to maintain said desired slope angle, and position sensing means operatively associated with said working element and responsive to the rotary position of said working element relative to the machine frame for modifying the given slope setting of said input slope signal means in relation to the rotary position of said working element, whereby said element establishes a planar surface having said predetermined cross slope regardless of the rotary position thereof during travel of said machine.
Claim 3
Dependent Claim
21 words
The control system according to claim 1 wherein, said slope sensing unit is mounted in fixed relation to said working element.
Claim 4
Dependent Claim
66 words
The control system of claim 1 wherein; said position sensing means is connected with said input slope signal means and adapted to produce a rotational correction signal related to the rotational position of the working element relative to the machine frame, said rotational correction signal being combined with said input slope signal to modify the same prior to being delivered to said slope signal mixing means.
Claim 5
Dependent Claim
67 words
The control system according to claim 2 wherein; said position sensing means is connected with said input slope signal means and adapted to produce a rotational correction signal related to the rotational position of the working element relative to the machine frame, said rotational correction signal being combined with said input slope signal to modify the same prior to being delivered to said slope signal mixing means.
Claim 6
Dependent Claim
266 words
In a traveling machine having a movable frame, an elongated surface working element supported by said frame, an adjustment means on the machine to adjust the elevation of at least one end of said element relative to said frame, said machine being adapted to establish a planar surface having a predetermined cross slope angle defined as the angle between the surface established and a horizontal plane, said angle being located in a vertical plane perpendicular to the direction of travel of the machine, a control system comprising in combination; a slope sensing unit operatively associated with said working element and Having means to produce a slope signal proportional to the degree of inclination of said element relative to a horizontal plane, input slope signal means providing a constant signal of predetermined value corresponding to the desired slope angle of the working element, slope signal mixing means adapted to produce a difference signal representing the difference between said input slope signal and said sensed slope signal, slope control means responsive to said difference signal for controlling said adjustment means for correcting the elevation of said one end of said working element to maintain said desired slope angle, and position sensing means operatively associated with said working element and responsive to the rotary position of said working element relative to the machine frame for modifying the given slope setting of said input slope signal means in relation to the rotary position of said working element, whereby said element establishes a planar surface having said predetermined cross slope regardless of the rotary position thereof during travel of said machine.
Claim 7
Dependent Claim
266 words
In a traveling machine having a movable frame, an elongated surface working element supported by said frame, an adjustment means on the machine to adjust the elevation of at least one end of said element relative to said frame, said machine being adapted to establish a planar surface having a predetermined cross slope angle defined as the angle between the surface established and a horizontal plane, said angle being located in a vertical plane perpendicular to the direction of travel of the machine, a control system comprising in combination; a slope sensing unit operatively associated with said working element and Having means to produce a slope signal proportional to the degree of inclination of said element relative to a horizontal plane, input slope signal means providing a constant signal of predetermined value corresponding to the desired slope angle of the working element, slope signal mixing means adapted to produce a difference signal representing the difference between said input slope signal and said sensed slope signal, slope control means responsive to said difference signal for controlling said adjustment means for correcting the elevation of said one end of said working element to maintain said desired slope angle, and position sensing means operatively associated with said working element and responsive to the rotary position of said working element relative to the machine frame for modifying the given slope setting of said input slope signal means in relation to the rotary position of said working element, whereby said element establishes a planar surface having said predetermined cross slope regardless of the rotary position thereof during travel of said machine.
Claim 8
Dependent Claim
21 words
The control system according to claim 5 wherein, said slope sensing unit is mounted in fixed relation to said working element.
Claim 9
Dependent Claim
66 words
The control system of claim 5 wherein said position sensing means is connected with said input slope signal means and adapted to produce a rotational correction signal related to the rotational position of the working element relative to the machine frame, said rotational correction signal being combined with said input slope signal to modify the same prior to being delivered to said slope signal mixing means.
Claim 10
Dependent Claim
66 words
The control system of claim 6 wherein; said position sensing means is connected with said input slope signal means and adapted to produce a rotational correction signal related to the rotational position of the working element relative to the machine frame, said rotational correction signal being combined with said input slope signal to modify the same prior to being delivered to said slope signal mixing means.
References Cited (Backward Citations)
US2961783A
Cited
US3026638A
Cited
US3303589A
Cited
US3454101A
Cited
US3554291A
Cited
US3495663A
Cited
US3486564A
Cited
US3674094A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1977-02-11 | 1977-08-13 | 1978-02-12 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1981-02-11 | 1981-08-13 | 1982-02-12 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1985-02-11 | 1985-08-13 | 1986-02-12 | $7700.00 | Window Closed / Lapsed |