Patent US4688028A successfully refreshed from Google Patents.
US4688028A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Audible low-fuel alarm for propane fuel tank
Assignee: Individual
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Filing: 1985-12-04
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Granted: 1987-08-18
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Expires: 2005-12-04
Abstract
Abstract An audible low-fuel alarm (50) for a pressurized propane fuel tank is disclosed. A Hall-effect sensor (57) is mounted in relation to a magnet (35) which is rotated in response to the level of fuel within the propane tank. When magnet (35) is rotated to a position to indicate a low fuel condition, the Hall-effect sensor (57) activates a buzzer 53. A mercury switch (55) prevents false low fuel alarms and conserves battery power during inflation of the balloon envelope.
Inventors
- 👤 Sidney H. Conn
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-24 18:46
CPC Classifications
G; G08; G08B; G08B21/00; G08B21/18; G08B21/182; G01; G01F; G01F23/00; G01F23/0007; G01F23/0015; G01F23/30; G01F23/32; G01F23/38; F; F17; F17C; F17C2250/00; F17C2250/04; F17C2250/0404; F17C2250/0408; F17C2250/0413; Y; Y10; Y10T; Y10T137/00; Y10T137/8158; Y10T137/8342
Claims Analysis
Total Claims: 11
Claim 1
Independent Claim
167 words
An audible low-fluid alarm for a fluid reservoir, comprising: (a) float means disposed within the fluid reservoir and movable within a predetermined range of travel responsive to the level of fluid within said reservoir; (b) a driver magnet rotatably mounted within said reservoir for rotational movement responsive to movement of said float means to define a magnetic field having a direction corresponding to a particular level of fluid within the reservoir; (c) sensor means exterior to said reservoir for detecting the magnetic field when in the direction corresponding to a particular level of liquid within the reservoir and outputting an electrical signal; (d) a driven magnet positioned in spaced-apart relation to said driver magnet and exterior to said reservoir, said sensor means being positioned between said driver magnet and said driven magnet in magnetic field sensing relation to both said magnets for providing a redundant sensing capability; and (e) audible alarm means connected to said sensor for activation by said electrical signal output from said sensor means.
Claim 2
Dependent Claim
167 words
An audible low-fluid alarm for a fluid reservoir, comprising: (a) float means disposed within the fluid reservoir and movable within a predetermined range of travel responsive to the level of fluid within said reservoir; (b) a driver magnet rotatably mounted within said reservoir for rotational movement responsive to movement of said float means to define a magnetic field having a direction corresponding to a particular level of fluid within the reservoir; (c) sensor means exterior to said reservoir for detecting the magnetic field when in the direction corresponding to a particular level of liquid within the reservoir and outputting an electrical signal; (d) a driven magnet positioned in spaced-apart relation to said driver magnet and exterior to said reservoir, said sensor means being positioned between said driver magnet and said driven magnet in magnetic field sensing relation to both said magnets for providing a redundant sensing capability; and (e) audible alarm means connected to said sensor for activation by said electrical signal output from said sensor means.
Claim 3
Dependent Claim
21 words
An audible low-fluid alarm according to claim 1, wherein said driven magnet is operably connected to a visual fluid level indicator.
Claim 4
Dependent Claim
17 words
An audible low-fluid alarm according to claim 1 or 2, wherein said sensor comprises a Hall-effect sensor.
Claim 5
Dependent Claim
38 words
An audible low-fluid alarm according to claims 1 or 2 and including an attitude sensor for electrically overriding said sensor means when said reservoir is in an other than predetermined desired attitude to prevent a false low-fluid alarm.
Claim 6
Dependent Claim
188 words
An audible low-fuel alarm for a pressurized propane fuel tank, comprising: (a) float means disposed within the fuel tank and movable within a range of travel responsive to the level of propane within said tank; (b) a driver magnet rotatably mounted within said tank for rotational movement responsive to movement of said float means to define a magnetic field having a direction corresponding to a particular level of fuel within said tank; (c) magnetic field sensing means exterior to said tank for detecting the magnetic field when in the direction corresponding to a particular level of fuel within the tank and outputting an electrical signal; (d) a driven magnet connected to a visual fluid level indicator, said driven magnet positioned in spaced apart relation to said driver magnet and said magnetic field sensing means, said magnetic field sensing means being positioned between said driver magnet and said driven magnet in magnetic field sensing relation to both magnets to provide a redundant sensing capability; and (e) audible alarm means connected to said magnetic field sensing means for activation by said electrical signal output from said magnetic field sensing means.
Claim 7
Dependent Claim
188 words
An audible low-fuel alarm for a pressurized propane fuel tank, comprising: (a) float means disposed within the fuel tank and movable within a range of travel responsive to the level of propane within said tank; (b) a driver magnet rotatably mounted within said tank for rotational movement responsive to movement of said float means to define a magnetic field having a direction corresponding to a particular level of fuel within said tank; (c) magnetic field sensing means exterior to said tank for detecting the magnetic field when in the direction corresponding to a particular level of fuel within the tank and outputting an electrical signal; (d) a driven magnet connected to a visual fluid level indicator, said driven magnet positioned in spaced apart relation to said driver magnet and said magnetic field sensing means, said magnetic field sensing means being positioned between said driver magnet and said driven magnet in magnetic field sensing relation to both magnets to provide a redundant sensing capability; and (e) audible alarm means connected to said magnetic field sensing means for activation by said electrical signal output from said magnetic field sensing means.
Claim 8
Dependent Claim
28 words
An audible low-fuel alarm for a pressurized propane fuel tank according to claim 5, wherein said propane fuel tank comprises a fuel tank for a hot air balloon.
Claim 9
Dependent Claim
38 words
An audible low-fluid alarm according to claims 5 or 6 and including an attitude sensor for electrically overriding said sensor means when said reservoir is in an other than predetermined desired attitude to prevent a false low-fluid alarm.
Claim 10
Dependent Claim
193 words
An audible low-fuel alarm for a pressurized propane fuel system for a hot air balloon, comprising: (a) float means disposed within a fuel tank and movable within a range of travel responsive to the level of propane within said tank; (b) a driver magnet rotatably mounted within said tank for rotational movement responsive to movement of said float means to define a magnetic field having a direction corresponding to a particular level of fuel within said tank; (c) magnetic field sensing means exterior to said tank for detecting the magnetic field when in the direction corresponding to a particular level of fuel within the tank and outputting an electrical signal; (d) a driven magnet connected to a visual fluid level indicator, said driven magnet positioned in spaced apart relation to said driver magnet and said magnetic field sensing means, said magnetic field sensing means being positioned between said driver magnet and said driven magnet in magnetic field sensing relation to both magnets to provide a redundant sensing capability; and (e) audible alarm means connected to said magnetic field sensing means for activation by said electrical signal output from said magnetic field sensing means.
Claim 11
Dependent Claim
193 words
An audible low-fuel alarm for a pressurized propane fuel system for a hot air balloon, comprising: (a) float means disposed within a fuel tank and movable within a range of travel responsive to the level of propane within said tank; (b) a driver magnet rotatably mounted within said tank for rotational movement responsive to movement of said float means to define a magnetic field having a direction corresponding to a particular level of fuel within said tank; (c) magnetic field sensing means exterior to said tank for detecting the magnetic field when in the direction corresponding to a particular level of fuel within the tank and outputting an electrical signal; (d) a driven magnet connected to a visual fluid level indicator, said driven magnet positioned in spaced apart relation to said driver magnet and said magnetic field sensing means, said magnetic field sensing means being positioned between said driver magnet and said driven magnet in magnetic field sensing relation to both magnets to provide a redundant sensing capability; and (e) audible alarm means connected to said magnetic field sensing means for activation by said electrical signal output from said magnetic field sensing means.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1990-08-17 | 1991-02-16 | 1991-08-18 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1994-08-17 | 1995-02-16 | 1995-08-18 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1998-08-17 | 1999-02-16 | 1999-08-18 | $7700.00 | Window Closed / Lapsed |