Patent US5934431A successfully refreshed from Google Patents.
US5934431A
Expired / Lapsed
US
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Plateau control algorithm for an electro-hydraulic actuator
Assignee: Dana Inc
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Filing: 1996-12-30
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Granted: 1999-08-10
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Expires: 2016-12-30
Abstract
Abstract A control system and method for operating the solenoid valves for controlling the supply of hydraulic fluid to a hydraulic actuator is described. The system and the method involves initially applying a first, increasing linear pressure up to a predetermined magnitude and then holding the pressure at that level for a period of time. This predetermined magnitude is equal to the amount of pressure required to cause initial movement of the piston. By holding the pressure level at a plateau for a period of time, the initial movement of the piston is accomplished in a smooth manner. This period of time is relatively short, typically less than one second. Thereafter, the system and the method involve operating the solenoid valves so as to apply a second, increasing linear pressure up to a predetermined final magnitude.
Inventors
- 👤 Craig W. Bladow
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-02 12:57
CPC Classifications
F; F15; F15B; F15B21/00; F15B21/008; F15B11/00; F15B11/02; F15B11/04; F15B11/042; F15B21/08; F15B21/087; F15B2211/00; F15B2211/50; F15B2211/505; F15B2211/50554; F15B2211/515; F15B2211/5159; F15B2211/52; F15B2211/526; F15B2211/60; F15B2211/63; F15B2211/6303; F15B2211/634; F15B2211/665; F15B2211/6653; F15B2211/70; F15B2211/705; F15B2211/7051; F15B2211/7052
Claims Analysis
Total Claims: 22
Claim 1
Independent Claim
116 words
A method for controlling the operation of an electrically-operated valve adapted for supplying hydraulic fluid to a hydraulic actuator, said method comprising: providing a first gradually increasing valve position signal from an initial valve position up to a threshold valve position, said threshold valve position being representative of a hydraulic fluid pressure which is sufficient to cause said hydraulic actuator to begin to move, providing a constant valve position signal for a time period which starts when said threshold valve position is reached, and providing a second gradually increasing valve position signal after said time period expires, said second increasing valve position signal being provided from said threshold valve position up to a target valve position.
Claim 2
Independent Claim
116 words
A method for controlling the operation of an electrically-operated valve adapted for supplying hydraulic fluid to a hydraulic actuator, said method comprising: providing a first gradually increasing valve position signal from an initial valve position up to a threshold valve position, said threshold valve position being representative of a hydraulic fluid pressure which is sufficient to cause said hydraulic actuator to begin to move, providing a constant valve position signal for a time period which starts when said threshold valve position is reached, and providing a second gradually increasing valve position signal after said time period expires, said second increasing valve position signal being provided from said threshold valve position up to a target valve position.
Claim 3
Dependent Claim
30 words
The method defined in claim 1 wherein said time period of said constant valve position signal is shorter than time periods of said first and second increasing valve position signals.
Claim 4
Dependent Claim
21 words
The method defined in claim 1 wherein said time period of said constant valve position signal is less than one second.
Claim 5
Dependent Claim
17 words
The method defined in claim 1 wherein said first and second increasing valve position signals are linear.
Claim 6
Dependent Claim
31 words
The method defined in claim 1 wherein said first and second increasing valve position signals and said constant valve position signal are adapted to cause said hydraulic actuator to move smoothly.
Claim 7
Dependent Claim
23 words
The method defined in claim 1 wherein said threshold valve position and said time period of said constant valve position signal are predetermined.
Claim 8
Dependent Claim
147 words
An electro-hydraulic actuator assembly comprising: a hydraulic actuator adapted for movement to control an associated device, an electrically-operated valve adapted for supplying hydraulic fluid to said hydraulic actuator to cause said movement, and an electronic controller adapted for transmitting signals to control the operation of said valve, said electronic controller being programmed for: providing a first gradually increasing valve position signal from an initial valve position up to a threshold valve position, said threshold valve position being representative of a hydraulic fluid pressure which is sufficient to cause said hydraulic actuator to begin to move, providing a constant valve position signal for a time period which starts when said threshold valve position is reached, and providing a second gradually increasing valve position signal after said time period expires, said second increasing valve position signal being provided from said threshold valve position up to a target valve position.
Claim 9
Dependent Claim
147 words
An electro-hydraulic actuator assembly comprising: a hydraulic actuator adapted for movement to control an associated device, an electrically-operated valve adapted for supplying hydraulic fluid to said hydraulic actuator to cause said movement, and an electronic controller adapted for transmitting signals to control the operation of said valve, said electronic controller being programmed for: providing a first gradually increasing valve position signal from an initial valve position up to a threshold valve position, said threshold valve position being representative of a hydraulic fluid pressure which is sufficient to cause said hydraulic actuator to begin to move, providing a constant valve position signal for a time period which starts when said threshold valve position is reached, and providing a second gradually increasing valve position signal after said time period expires, said second increasing valve position signal being provided from said threshold valve position up to a target valve position.
Claim 10
Dependent Claim
31 words
The actuator assembly defined in claim 7 wherein said time period of said constant valve position signal is shorter than time periods of said first and second increasing valve position signals.
Claim 11
Dependent Claim
22 words
The actuator assembly defined in claim 7 wherein said time period of said constant valve position signal is less than one second.
Claim 12
Dependent Claim
18 words
The actuator assembly defined in claim 7 wherein said first and second increasing valve position signals are linear.
Claim 13
Dependent Claim
32 words
The actuator assembly defined in claim 7 wherein said first and second increasing valve position signals and said constant valve position signal are adapted to cause said hydraulic actuator to move smoothly.
Claim 14
Dependent Claim
24 words
The actuator assembly defined in claim 7 wherein said threshold valve position and said time period of said constant valve position signal are predetermined.
Claim 15
Dependent Claim
27 words
The actuator assembly defined in claim 7 wherein said hydraulic actuator comprises a cylinder having a piston disposed therein which is connected for movement with said device.
Claim 16
Dependent Claim
142 words
An electro-hydraulic actuator assembly comprising: a hydraulic actuator, an electrically-operated valve adapted for supplying hydraulic fluid to said hydraulic actuator to cause movement of said hydraulic actuator, and an electronic controller adapted for transmitting signals to control the operation of said valve, said electronic controller being programmed for: providing a first gradually increasing valve position signal from an initial valve position up to a threshold valve position, said threshold valve position being representative of a hydraulic fluid pressure which is sufficient to cause said hydraulic actuator to begin to move, providing a constant valve position signal for a time period which starts when said threshold valve position is reached, and providing a second gradually increasing valve position signal after said time period expires, said second increasing valve position signal being provided from said threshold valve position up to a target valve position.
Claim 17
Dependent Claim
142 words
An electro-hydraulic actuator assembly comprising: a hydraulic actuator, an electrically-operated valve adapted for supplying hydraulic fluid to said hydraulic actuator to cause movement of said hydraulic actuator, and an electronic controller adapted for transmitting signals to control the operation of said valve, said electronic controller being programmed for: providing a first gradually increasing valve position signal from an initial valve position up to a threshold valve position, said threshold valve position being representative of a hydraulic fluid pressure which is sufficient to cause said hydraulic actuator to begin to move, providing a constant valve position signal for a time period which starts when said threshold valve position is reached, and providing a second gradually increasing valve position signal after said time period expires, said second increasing valve position signal being provided from said threshold valve position up to a target valve position.
Claim 18
Dependent Claim
32 words
The electro-hydraulic actuator assembly defined in claim 14 wherein said time period of said constant valve position signal is shorter than time periods of said first and second increasing valve position signals.
Claim 19
Dependent Claim
23 words
The electro-hydraulic actuator assembly defined in claim 14 wherein said time period of said constant valve position signal is less than one second.
Claim 20
Dependent Claim
19 words
The electro-hydraulic actuator assembly defined in claim 14 wherein said first and second increasing valve position signals are linear.
Claim 21
Dependent Claim
33 words
The electro-hydraulic actuator assembly defined in claim 14 wherein said first and second increasing valve position signals and said constant valve position signal are adapted to cause said hydraulic actuator to move smoothly.
Claim 22
Dependent Claim
20 words
The electro-hydraulic actuator assembly defined in claim 14 wherein said hydraulic actuator comprises a cylinder having a piston disposed therein.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
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| 3.5 Years (Year 4) | 2002-08-09 | 2003-02-08 | 2003-08-10 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2006-08-09 | 2007-02-08 | 2007-08-10 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2010-08-09 | 2011-02-08 | 2011-08-10 | $7700.00 | Window Closed / Lapsed |