Patent US1419346A successfully refreshed from Google Patents.
Patent US5528843A successfully refreshed from Google Patents.
US5528843A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Control system for automatically controlling a work implement of an earthworking machine to capture material
Assignee: Caterpillar Inc
•
Filing: 1994-08-18
•
Granted: 1996-06-25
•
Expires: 2014-08-18
Abstract
Abstract In one aspect of the present invention, an automatic control system for loading a bucket of a wheel loader is disclosed. The system includes a pressure sensor that produces pressure signals in response to the hydraulic pressures associated with one of the lift and tilt cylinders. A microprocessor receives the pressure signals, compares at least one of the pressure signals to a predetermined one of a plurality of pressure setpoints, and produces lift and tilt command signals in response to the pressure comparisons. Finally, an electrohydraulic system receives the lift command signals and controllably extends the lift cylinder to raise the bucket through the material, and receives the tilt command signals and controllably extends the tilt cylinder to tilt the bucket to capture the material.
Inventors
- 👤 David J. Rocke
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-04 10:41
CPC Classifications
E; E02; E02F; E02F3/00; E02F3/04; E02F3/28; E02F3/36; E02F3/42; E02F3/43; E02F3/431; E02F3/434
Claims Analysis
Total Claims: 11
Claim 1
Independent Claim
203 words
A control system for automatically controlling a work implement of an earthworking machine to capture material, the work implement including a bucket, the bucket being controllably actuated by a lift hydraulic cylinder and a tilt hydraulic cylinder, comprising: pressure sensing means for producing respective pressure signals in response to the hydraulic pressures associated with at least one of the lift and tilt cylinders; force computing means for receiving the pressure signals and responsively computing correlative force signals; logic means for receiving the force signals and responsively producing the tilt cylinder command signals to tilt the bucket in response to the lift cylinder force exceeding an upper pressure threshold, and producing the tilt cylinder command signals to stop the bucket tilting in response to the lift cylinder force falling below a lower pressure threshold and responsively producing lift cylinder command signals in response to comparing at least one of the pressure signals to a predetermined one of a plurality of pressure setpoints; and actuating means for receiving the lift command signals and controllably extending the lift cylinder to raise the bucket through the material, and receiving the tilt command signals and controllably extending the tilt cylinder to tilt the bucket to capture the material.
Claim 2
Dependent Claim
203 words
A control system for automatically controlling a work implement of an earthworking machine to capture material, the work implement including a bucket, the bucket being controllably actuated by a lift hydraulic cylinder and a tilt hydraulic cylinder, comprising: pressure sensing means for producing respective pressure signals in response to the hydraulic pressures associated with at least one of the lift and tilt cylinders; force computing means for receiving the pressure signals and responsively computing correlative force signals; logic means for receiving the force signals and responsively producing the tilt cylinder command signals to tilt the bucket in response to the lift cylinder force exceeding an upper pressure threshold, and producing the tilt cylinder command signals to stop the bucket tilting in response to the lift cylinder force falling below a lower pressure threshold and responsively producing lift cylinder command signals in response to comparing at least one of the pressure signals to a predetermined one of a plurality of pressure setpoints; and actuating means for receiving the lift command signals and controllably extending the lift cylinder to raise the bucket through the material, and receiving the tilt command signals and controllably extending the tilt cylinder to tilt the bucket to capture the material.
Claim 3
Dependent Claim
72 words
A control system, as set forth in claim 1, including: means for producing respective position signals in response to the respective position of at least one of the lift and tilt cylinders; and means for receiving the position signals, comparing the position signals to a plurality of positional setpoints, and indicating when the loading is complete in response to the tilt or lift cylinder positions being greater that a respective positional setpoint.
Claim 4
Dependent Claim
203 words
A control system for automatically controlling a work implement of an earthworking machine to capture material, the work implement including a bucket, the bucket being controllably actuated by a lift hydraulic cylinder and a tilt hydraulic cylinder, comprising: pressure sensing means for producing respective pressure signals in response to the hydraulic pressures associated with at least one of the lift and tilt cylinders; force computing means for receiving the pressure signals and responsively computing correlative force signals; logic means for receiving the force signals and responsively producing the tilt cylinder command signals to tilt the bucket in response to the tilt cylinder force exceeding an upper pressure threshold, and producing the tilt cylinder command signals to stop the bucket tilting in response to the tilt cylinder force falling below a lower pressure threshold and responsively producing lift cylinder command signals in response to comparing at least one of the pressure signals to a predetermined one of a plurality of pressure setpoints; and actuating means for receiving the lift command signals and controllably extending the lift cylinder to raise the bucket through the material, and receiving the tilt command signals and controllably extending the tilt cylinder to tilt the bucket to capture the material.
Claim 5
Dependent Claim
203 words
A control system for automatically controlling a work implement of an earthworking machine to capture material, the work implement including a bucket, the bucket being controllably actuated by a lift hydraulic cylinder and a tilt hydraulic cylinder, comprising: pressure sensing means for producing respective pressure signals in response to the hydraulic pressures associated with at least one of the lift and tilt cylinders; force computing means for receiving the pressure signals and responsively computing correlative force signals; logic means for receiving the force signals and responsively producing the tilt cylinder command signals to tilt the bucket in response to the tilt cylinder force exceeding an upper pressure threshold, and producing the tilt cylinder command signals to stop the bucket tilting in response to the tilt cylinder force falling below a lower pressure threshold and responsively producing lift cylinder command signals in response to comparing at least one of the pressure signals to a predetermined one of a plurality of pressure setpoints; and actuating means for receiving the lift command signals and controllably extending the lift cylinder to raise the bucket through the material, and receiving the tilt command signals and controllably extending the tilt cylinder to tilt the bucket to capture the material.
Claim 6
Dependent Claim
72 words
A control system, as set forth in claim 3, including: means for producing respective position signals in response to the respective position of at least one of the lift and tilt cylinders; and means for receiving the position signals, comparing the position signals to a plurality of positional setpoints, and indicating when the loading is complete in response to the tilt or lift cylinder positions being greater that a respective positional setpoint.
Claim 7
Independent Claim
150 words
A method for automatically controlling a work implement of an earthworking machine to capture material, the work implement including a bucket, the bucket being controllably actuated by a hydraulic lift cylinder and a hydraulic tilt cylinder, the method comprising the steps of: producing respective pressure signals in response to the hydraulic pressures associated with at least one of the lift and tilt cylinders; and producing the tilt cylinder command signals to tilt the bucket in response to the lift cylinder pressure exceeding an upper pressure threshold; and producing the tilt cylinder command signals to stop the bucket tilting in response to the lift cylinder pressure falling below a lower pressure threshold; and comparing the pressure signals to a plurality of pressure setpoints, and producing lift cylinder command signals to raise the bucket in response to one of the lift or tilt cylinder pressures being greater than a respective predetermined setpoint.
Claim 8
Independent Claim
150 words
A method for automatically controlling a work implement of an earthworking machine to capture material, the work implement including a bucket, the bucket being controllably actuated by a hydraulic lift cylinder and a hydraulic tilt cylinder, the method comprising the steps of: producing respective pressure signals in response to the hydraulic pressures associated with at least one of the lift and tilt cylinders; and producing the tilt cylinder command signals to tilt the bucket in response to the lift cylinder pressure exceeding an upper pressure threshold; and producing the tilt cylinder command signals to stop the bucket tilting in response to the lift cylinder pressure falling below a lower pressure threshold; and comparing the pressure signals to a plurality of pressure setpoints, and producing lift cylinder command signals to raise the bucket in response to one of the lift or tilt cylinder pressures being greater than a respective predetermined setpoint.
Claim 9
Dependent Claim
72 words
A method, as set forth in claim 5, including the steps of: producing respective position signals in response to the respective position of at least one of the lift and tilt cylinders; and receiving the position signals, comparing the position signals to a plurality of positional setpoints, and indicating when the loading is complete in response to the tilt cylinder position or lift cylinder position being greater that a respective positional setpoint.
Claim 10
Independent Claim
151 words
A method for automatically controlling a work implement of an earthworking machine to capture material, the work implement including a bucket, the bucket being controllably actuated by a hydraulic lift cylinder and a hydraulic tilt cylinder, the method comprising the steps of: producing respective pressure signals in response to the associated hydraulic pressures associated with at least one of the lift and tilt cylinders; and producing the tilt cylinder command signals to tilt the bucket in response to the tilt cylinder pressure exceeding an upper pressure threshold; and producing the tilt cylinder command signals to stop the bucket tilting in response to the tilt cylinder pressure falling below a lower pressure threshold; and comparing the pressure signals to a plurality of pressure setpoints, and producing lift cylinder command signals to raise the bucket in response to one of the lift or tilt cylinder pressures being greater than a respective predetermined setpoint.
Claim 11
Independent Claim
151 words
A method for automatically controlling a work implement of an earthworking machine to capture material, the work implement including a bucket, the bucket being controllably actuated by a hydraulic lift cylinder and a hydraulic tilt cylinder, the method comprising the steps of: producing respective pressure signals in response to the associated hydraulic pressures associated with at least one of the lift and tilt cylinders; and producing the tilt cylinder command signals to tilt the bucket in response to the tilt cylinder pressure exceeding an upper pressure threshold; and producing the tilt cylinder command signals to stop the bucket tilting in response to the tilt cylinder pressure falling below a lower pressure threshold; and comparing the pressure signals to a plurality of pressure setpoints, and producing lift cylinder command signals to raise the bucket in response to one of the lift or tilt cylinder pressures being greater than a respective predetermined setpoint.
References Cited (Backward Citations)
US3583585A
Cited
US4052602A
Cited
US4332517A
Cited
US4377043A
Cited
US4491918A
Cited
US4517645A
Cited
US5327347A
Cited
US4839835A
Cited
US4839835B1
Cited
US4742468A
Cited
US4964779A
Cited
US4910673A
Cited
US5287280A
Cited
US5178510A
Cited
US5116186A
Cited
US5160239A
Cited
US5002454A
Cited
US5065326A
Cited
US5128599A
Cited
US5218895A
Cited
US5182712A
Cited
US5308219A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1999-06-25 | 1999-12-25 | 2000-06-25 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2003-06-25 | 2003-12-25 | 2004-06-25 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2007-06-25 | 2007-12-25 | 2008-06-25 | $7700.00 | Window Closed / Lapsed |