Patent US3913680A successfully refreshed from Google Patents.
US3913680A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Control system for percentage of wheel slippage of a tractor
Assignee: Deutz Allis Corp
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Filing: 1974-05-30
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Granted: 1975-10-21
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Expires: 1994-05-30
Abstract
Abstract Apparatus for determining the percentage of wheel slippage of the drive wheel of a tractor and using a hydraulic weight distribution system to distribute the weight of the tractor and maintain a desired percentage of wheel slippage, preferably 12-15 percent. A signal from a signal generator on a freely rotatable wheel is compared to a signal from a signal generator connected to a drive wheel to obtain a difference signal which is then compared with the signal from the signal generator connected to the drive wheel to obtain percentage of wheel slippage. This actual percentage is compared with a signal from a potentiometer set to represent a desired percentage slip and the resultant signal is used to control hydraulic actuators to raise and lower the three point hitch and connected implement to maintain a desired percentage of wheel slippage.
Inventors
- 👤 Richard G Carlson
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-24 01:53
CPC Classifications
A; A01; A01B; A01B63/00; A01B63/02; A01B63/10; A01B63/111; A01B63/114; A01B63/1145; B; B60; B60T; B60T8/00; B60T8/17; B60T8/1701; B60T8/1708
Claims Analysis
Total Claims: 11
Claim 1
Independent Claim
275 words
A tractor comprising, a three point hitch adapted for connection to an implement, a pair of lower draft arms in said three point hitch, a hydraulic weight distribution system including hydraulic actuators connected to said lower draft arms of said three point hitch for controlling implement position, at leaSt one drive wheel, a first signal generator connected to said drive wheel for sensing rotation of said drive wheel, at least one freely rotatable wheel, a second signal generator connected to said freely rotatable wheel for sensing rotation of said freely rotatable wheel, and electrical circuit including said signal generators, a signal comparator for comparing signals from said signal generators generating a difference signal, a second signal comparator for comparing said difference signal with the signal from said signal generator connected to said drive wheel for generating a ratio signal proportional to and indicating the percentage of wheel slippage of said drive wheel, a reference signal generator for generating a reference signal indicative of desired percentage of wheel slippage, a signal summer for summing the ratio signal and the reference signal and generating a control signal, an electrically operated control valve in said hydraulic weight distribution system connected to said actuators for distributing the weight of said tractor to and from said drive wheel by controlling said actuators, conductors between said signal summer and electrically operated control valve to transmit said control signal to said electrically operated control valve to thereby control said valve for distribution of the weight of said tractor to and from said drive wheel responsive to deviation of actual percentage of drive wheel slippage from the desired percentage of drive wheel slippage.
Claim 2
Dependent Claim
275 words
A tractor comprising, a three point hitch adapted for connection to an implement, a pair of lower draft arms in said three point hitch, a hydraulic weight distribution system including hydraulic actuators connected to said lower draft arms of said three point hitch for controlling implement position, at leaSt one drive wheel, a first signal generator connected to said drive wheel for sensing rotation of said drive wheel, at least one freely rotatable wheel, a second signal generator connected to said freely rotatable wheel for sensing rotation of said freely rotatable wheel, and electrical circuit including said signal generators, a signal comparator for comparing signals from said signal generators generating a difference signal, a second signal comparator for comparing said difference signal with the signal from said signal generator connected to said drive wheel for generating a ratio signal proportional to and indicating the percentage of wheel slippage of said drive wheel, a reference signal generator for generating a reference signal indicative of desired percentage of wheel slippage, a signal summer for summing the ratio signal and the reference signal and generating a control signal, an electrically operated control valve in said hydraulic weight distribution system connected to said actuators for distributing the weight of said tractor to and from said drive wheel by controlling said actuators, conductors between said signal summer and electrically operated control valve to transmit said control signal to said electrically operated control valve to thereby control said valve for distribution of the weight of said tractor to and from said drive wheel responsive to deviation of actual percentage of drive wheel slippage from the desired percentage of drive wheel slippage.
Claim 3
Dependent Claim
32 words
A tractor as set forth in claim 1 wherein said drive wheel defines a rear drive wheel for driving said tractor, said freely rotatable wheel defines a front wheel of said tractor.
Claim 4
Dependent Claim
55 words
A tractor as set forth in claim 1 including a pair of front wheels, a signal generator connected to sense rotation of the first front wheel, a signal generator connected to sense wheel rotation of the second front wheel, a circuit including means connecting said first and second signal generators to generate an average signal.
Claim 5
Dependent Claim
38 words
A tractor as set forth in claim 1 including, a propeller shaft for driving a pair of rear wheels, means connecting said second signal generator to said propeller shaft for sensing average wheel rotation of said rear wheels.
Claim 6
Dependent Claim
66 words
A tractor as set forth in claim 1 including two freely rotatable wheels, said signal generator including means for sensing the average wheel rotation of said two freely rotatable wheels, a pair of rear wheels, a propeller shaft driving said rear wheels, said second signal generator connected to said propeller shaft for sensing the average rotation of said rear wheels to thereby sense rear wheel slippage.
Claim 7
Dependent Claim
35 words
A tractor as set forth in claim 1 including a manually adjustable signal generator for generating the reference wheel slip signal for presetting the predetermined wheel slippage range of the drive wheel of said tractor.
Claim 8
Dependent Claim
32 words
A tractor as set forth in claim 1 including a limit switch in said electrical circuit limiting the lowest position of one of said lower draft arms of said three point hitch.
Claim 9
Dependent Claim
60 words
A tractor as set forth in claim 1 including a signal transmission means in said electrical circuit including a diode and a switch for transmitting a signal to said electrically operated valve, mechanical means operating said switch for limiting the weight transfer and low position of said three point hitch by providing unidirectional signal transmission when said switch is open.
Claim 10
Dependent Claim
28 words
A tractor as set forth in claim 1 including a manually operated signal circuit connected to said electrically operated valve for selectively operating said hydraulic weight distribution system.
Claim 11
Dependent Claim
67 words
A tractor as set forth in claim 1 including a pair of front wheels including said freely rotatable wheel, said second signal generator generating a signal responsive to the average rate of rotation of said front wheels, a pair of rear drive wheels including said one drive wheel, said first signal generator generating a signal responsive to the average rate of wheel rotation of said rear wheels.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1978-10-20 | 1979-04-21 | 1979-10-21 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1982-10-20 | 1983-04-21 | 1983-10-21 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1986-10-20 | 1987-04-21 | 1987-10-21 | $7700.00 | Window Closed / Lapsed |