US4726583A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Passive hydraulic resistance system
Assignee: OLSEN CONTROLS Inc 664 BIRCH STREET BRISTOL CT 06010 A CORP OF NEW HAMPSHIRE
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Filing: 1986-11-19
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Granted: 1988-02-23
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Expires: 2006-11-19
Abstract
Abstract A exercising machine has a pivotal lever and includes a passive electrohydraulic resistance system which provides controlled resistance to lever movement. Hydraulic fluid which may leak from a piston-cylinder assembly, which comprises part of the system, collects in a sump and is sucked into the piston-cylinder assembly during the normal operating cycle of the exercise machine.
Inventors
- 👤 Zenny Olsen
- 👤 Benny Olsen
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-28 07:17
CPC Classifications
A; A63; A63B; A63B21/00; A63B21/008; A63B21/0083; A63B21/00058; A63B21/00069; A63B21/00072; A63B21/40; A63B21/4041; A63B21/4047; Y; Y10; Y10S; Y10S482/00; Y10S482/901; Y10S482/902
Claims Analysis
Total Claims: 13
Claim 1
Independent Claim
413 words
A passive hydraulic resistance system charged with hydraulic fluid and comprising a housing and a piston assembly including a piston supported for movement in one and an opposite direction within and relative to said housing and connecting means in the form of a connecting rod for driving said piston in said one and said opposite direction in response to forces applied to said rod, said piston assembly cooperating with said housing to define first and second chambers of variable volume separated from each other by said piston, said piston and rod being movable within and relative to said housing to simultaneously decrease the volume of one of said chambers and increase the volume of the other of said chambers, said piston and rod displacing a greater volume of fluid in moving in one direction to expel fluid from said first chamber than in moving through an equal distance in an opposite direction within and relative to said housing to expel fluid from said second chamber, a sump for containing a quantity of hydraulic fluid, control valve means for exclusively regulating hydraulic fluid flow within said system, means defining a first flow path from said first chamber to said second chamber, first check valve means for allowing fluid flow along said first path from said first chamber to said second chamber and preventing fluid flow along said first path from said second chamber to said first chamber, means for defining a second flow path from said first chamber to said control valve means, said first check valve means allowing fluid flow from said first chamber along said second flow path to said control valve means and preventing fluid flow along said second flow path to said first chamber, a portion of said first flow path between said first check valve means and said second chamber being connected with the second flow path and thereby with the control valve means and allowing unrestricted fluid flow to and from said second chamber, means defining a third flow path from said control valve means to said sump for allowing fluid flow from said control valve means to said sump, means defining a fourth flow path from said sump to said first chamber in bypassing relation to said control valve means, and second check valve means for allowing fluid flow along said fourth flow path from said sump to said first chamber and preventing fluid flow along said fourth flow path from said first chamber to said sump.
Claim 2
Dependent Claim
413 words
A passive hydraulic resistance system charged with hydraulic fluid and comprising a housing and a piston assembly including a piston supported for movement in one and an opposite direction within and relative to said housing and connecting means in the form of a connecting rod for driving said piston in said one and said opposite direction in response to forces applied to said rod, said piston assembly cooperating with said housing to define first and second chambers of variable volume separated from each other by said piston, said piston and rod being movable within and relative to said housing to simultaneously decrease the volume of one of said chambers and increase the volume of the other of said chambers, said piston and rod displacing a greater volume of fluid in moving in one direction to expel fluid from said first chamber than in moving through an equal distance in an opposite direction within and relative to said housing to expel fluid from said second chamber, a sump for containing a quantity of hydraulic fluid, control valve means for exclusively regulating hydraulic fluid flow within said system, means defining a first flow path from said first chamber to said second chamber, first check valve means for allowing fluid flow along said first path from said first chamber to said second chamber and preventing fluid flow along said first path from said second chamber to said first chamber, means for defining a second flow path from said first chamber to said control valve means, said first check valve means allowing fluid flow from said first chamber along said second flow path to said control valve means and preventing fluid flow along said second flow path to said first chamber, a portion of said first flow path between said first check valve means and said second chamber being connected with the second flow path and thereby with the control valve means and allowing unrestricted fluid flow to and from said second chamber, means defining a third flow path from said control valve means to said sump for allowing fluid flow from said control valve means to said sump, means defining a fourth flow path from said sump to said first chamber in bypassing relation to said control valve means, and second check valve means for allowing fluid flow along said fourth flow path from said sump to said first chamber and preventing fluid flow along said fourth flow path from said first chamber to said sump.
Claim 3
Dependent Claim
40 words
A passive hydraulic resistance system as set forth in claim 1 wherein said device includes sensing means connected to said conduit means for providing an output signal indicative of the force applied to said connecting means in moving said piston.
Claim 4
Dependent Claim
19 words
A passive hydraulic resistance system as set forth in claim 2 wherein said sensing means comprising a pressure transducer.
Claim 5
Dependent Claim
19 words
A passive hydraulic resistance system as set forth in claim 1 wherein said control valve means comprises a servovalve.
Claim 6
Dependent Claim
33 words
A passive hydraulic resistance system as set forth in claim 1 wherein said piston displaces twice the volume of fluid in moving in said one direction than in moving in said opposite direction.
Claim 7
Dependent Claim
54 words
A passive hydraulic resistance system as set forth in claim 1 wherein said connecting rod attaches to said piston within said housing and projects from said housing through an opening in said housing, and said sump is positioned relative to said opening to receive fluid which may leak from said housing through said opening.
Claim 8
Dependent Claim
19 words
A passive hydraulic resistance system as set forth in claim 6 wherein said sump is located below said opening.
Claim 9
Dependent Claim
35 words
A passive hydraulic resistance system as set forth in claim 1 wherein said second flow path forms a junction with said first flow path between said first check valve means and said control valve means.
Claim 10
Dependent Claim
58 words
A passive hydraulic resistance system as set forth in claim 8 wherein said connecting means comprises a piston rod attached to said piston within said housing and projecting from said housing through an opening in said housing and said sump is positioned relative to said opening to receive fluid which may leak from said housing through said opening.
Claim 11
Dependent Claim
19 words
A passive hydraulic resistance system as set forth in claim 9 wherein said sump is located below said opening.
Claim 12
Dependent Claim
407 words
A passive hydraulic resistance system charged with hydraulic fluid and comprising a housing and a piston assembly including a piston supported for movement in one and an opposite direction within and relative to said housing and connecting means in the form of a connecting rod for driving said piston in said one and said opposite direction in response to forces applied to said rod, said piston assembly cooperating with said housing to define first and second chambers of variable volume separated from each other by said piston, said piston and rod being movable within and relative to said housing to simultaneously decrease the volume of one of said chambers and increase the volume of the other of said chambers, said piston and rod displacing a greater volume of fluid in moving in one direction to expel fluid from said first chamber than in moving through an equal distance in an opposite direction within and relative to said housing to expel fluid from said second chamber, a sump for holding a quantity of hydraulic fluid, control valve means for exclusively regulating hydraulic fluid flow within said system, means defining a first flow path from said first chamber to said second chamber for directing fluid from the first chamber to the second chamber exclusive of the sump and the control valve means, first check valve means for allowing fluid flow along said first path from said first chamber to said second chamber and preventing fluid flow along said first path from said second chamber to said first chamber, means for defining a second flow path from said second chamber to said control valve means, said first check valve means causing fluid flow from said second chamber to move along said second flow path to said control valve means when said piston is moved in said opposite direction within and relative to said housing, said first flow path between said first check valve means and said second chamber also being in fluid communication with the control valve means by way of the second flow path, means defining a third flow path from said control valve means to said sump for allowing fluid flow from said control valve means to said sump, and means defining a fourth flow path from said sump to said first chamber in bypassing relation to said control valve means, and allowing a fluid flow along said fourth flow path from said sump to said first chamber.
Claim 13
Dependent Claim
407 words
A passive hydraulic resistance system charged with hydraulic fluid and comprising a housing and a piston assembly including a piston supported for movement in one and an opposite direction within and relative to said housing and connecting means in the form of a connecting rod for driving said piston in said one and said opposite direction in response to forces applied to said rod, said piston assembly cooperating with said housing to define first and second chambers of variable volume separated from each other by said piston, said piston and rod being movable within and relative to said housing to simultaneously decrease the volume of one of said chambers and increase the volume of the other of said chambers, said piston and rod displacing a greater volume of fluid in moving in one direction to expel fluid from said first chamber than in moving through an equal distance in an opposite direction within and relative to said housing to expel fluid from said second chamber, a sump for holding a quantity of hydraulic fluid, control valve means for exclusively regulating hydraulic fluid flow within said system, means defining a first flow path from said first chamber to said second chamber for directing fluid from the first chamber to the second chamber exclusive of the sump and the control valve means, first check valve means for allowing fluid flow along said first path from said first chamber to said second chamber and preventing fluid flow along said first path from said second chamber to said first chamber, means for defining a second flow path from said second chamber to said control valve means, said first check valve means causing fluid flow from said second chamber to move along said second flow path to said control valve means when said piston is moved in said opposite direction within and relative to said housing, said first flow path between said first check valve means and said second chamber also being in fluid communication with the control valve means by way of the second flow path, means defining a third flow path from said control valve means to said sump for allowing fluid flow from said control valve means to said sump, and means defining a fourth flow path from said sump to said first chamber in bypassing relation to said control valve means, and allowing a fluid flow along said fourth flow path from said sump to said first chamber.
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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) | 1991-02-22 | 1991-08-24 | 1992-02-23 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1995-02-22 | 1995-08-24 | 1996-02-23 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1999-02-22 | 1999-08-24 | 2000-02-23 | $7700.00 | Window Closed / Lapsed |