US5065829A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Hydraulic control system for weighing
Assignee: Wray Tech Instruments Inc
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Filing: 1990-11-16
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Granted: 1991-11-19
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Expires: 2010-11-16
Abstract
Abstract An hydraulic bypass control system for tapping off the lift circuit of an hydraulically operated lifting device. The bypass control system slowly releases hydraulic fluid from the lift circuit and directs it back to the reservoir in a controlled manner so a load is smoothly moved from a reference position to a weighing position. Reliable weighing may be obtained by avoiding dynamic shaking, vibration and pressure surges, which permits the weighing step to be reliably made at the same point or range and affords precise calibration of a load transducer with a weighing instrument to be made.
Inventors
- 👤 Ronald Smith
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-07 10:52
CPC Classifications
G; G01; G01G; G01G19/00; G01G19/08; B; B65; B65F; B65F3/00; B65F3/02; B65F2003/022; B65F2003/0263; B65F2003/0279
Claims Analysis
Total Claims: 8
Claim 1
Independent Claim
139 words
A motion control method for generating reliable analog electrical signals from a pressure transducer means and providing analog signals responsive to hydraulic fluid pressure caused by lifting a weight by means of an hydraulic lift assembly of a refuse collection vehicle, said method comprising the steps of: tapping off hydraulic fluid under pressure from the lift circuit of an hydraulic lift assembly of a refuse collection vehicle; bypassing said tapped off hydraulic fluid through an hydraulic bypass circuit; lowering a weight lifted by the hydraulic lift assembly; directing said tapped-off hydraulic fluid to hydraulic pressure transducer means sensing the pressure in the hydraulic bypass circuit and generating an analog electrical signal corresponding to the weight being lowered by said hydraulic lift assembly; communicating said analog signal to an analog/digital converter means; and, creating a digital record of the weight.
Claim 2
Dependent Claim
139 words
A motion control method for generating reliable analog electrical signals from a pressure transducer means and providing analog signals responsive to hydraulic fluid pressure caused by lifting a weight by means of an hydraulic lift assembly of a refuse collection vehicle, said method comprising the steps of: tapping off hydraulic fluid under pressure from the lift circuit of an hydraulic lift assembly of a refuse collection vehicle; bypassing said tapped off hydraulic fluid through an hydraulic bypass circuit; lowering a weight lifted by the hydraulic lift assembly; directing said tapped-off hydraulic fluid to hydraulic pressure transducer means sensing the pressure in the hydraulic bypass circuit and generating an analog electrical signal corresponding to the weight being lowered by said hydraulic lift assembly; communicating said analog signal to an analog/digital converter means; and, creating a digital record of the weight.
Claim 3
Dependent Claim
31 words
The method as claimed in claim 1 wherein the step of generating of an analog electrical signal from said transducer means occurring dynamically while said hydraulic lift assembly lowers the weight.
Claim 4
Dependent Claim
24 words
The method according to claim 1 wherein said tapping off step is preceded by opening a normally closed valve in the hydraulic bypass circuit.
Claim 5
Dependent Claim
27 words
The method according to claim 3 including prior to the tapping off step, generating an electrical signal when a lifted weight is lifted to a reference position.
Claim 6
Dependent Claim
26 words
The method according to claim 1 wherein the generating of an analog electrical signal occurring as said weight is statically held by said hydraulic lift assembly.
Claim 7
Dependent Claim
135 words
A motion control method for generating reliable analog electrical signals from a pressure transducer means and providing analog signals responsive to hydraulic fluid pressure caused by lifting a weight by means of an hydraulic lift assembly of a refuse collection vehicle, said method comprising the steps of: opening a normally closed valve in an hydraulic bypass circuit; tapping off hydraulic fluid under pressure from the lift circuit of an hydraulic lift assembly of a refuse collection vehicle into said hydraulic bypass circuit; lowering a weight lifted by the hydraulic lift assembly; directing said tapped-off hydraulic fluid to hydraulic pressure transducer means and generating an analog electrical signal corresponding to the weight being lifted by said hydraulic lift assembly; communicating said analog signal to an analog/digital converter means; and, creating a digital record to the weight.
Claim 8
Dependent Claim
135 words
A motion control method for generating reliable analog electrical signals from a pressure transducer means and providing analog signals responsive to hydraulic fluid pressure caused by lifting a weight by means of an hydraulic lift assembly of a refuse collection vehicle, said method comprising the steps of: opening a normally closed valve in an hydraulic bypass circuit; tapping off hydraulic fluid under pressure from the lift circuit of an hydraulic lift assembly of a refuse collection vehicle into said hydraulic bypass circuit; lowering a weight lifted by the hydraulic lift assembly; directing said tapped-off hydraulic fluid to hydraulic pressure transducer means and generating an analog electrical signal corresponding to the weight being lifted by said hydraulic lift assembly; communicating said analog signal to an analog/digital converter means; and, creating a digital record to the weight.
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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) | 1994-11-18 | 1995-05-20 | 1995-11-19 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1998-11-18 | 1999-05-20 | 1999-11-19 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2002-11-18 | 2003-05-20 | 2003-11-19 | $7700.00 | Window Closed / Lapsed |