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US3685504A Expired / Lapsed US ⏱️ 0.0 years remaining

Fuel tank ventilation in motor vehicles

Assignee: Fiat SpA
•
Filing: 1970-11-12
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Granted: 1972-08-22
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Expires: 1990-11-12
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Abstract

Abstract A motor vehicle fuel tank having at least two spaced apart holes on its surface with each of the holes being connected to a fuel vapor trap. To prevent liquid fuel from leaving the tank and entering the trap, each hole is controlled by a float valve connected between the hole and the trap.

Inventors

  • 👤 Giovanni Torazza

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-11-01 09:23
CPC Classifications
B; B60; B60K; B60K15/00; B60K15/03; B60K15/035; B60K15/03519

Claims Analysis

Total Claims: 4
Claim 1
Independent Claim 281 words
A motor vehicle having an elongated fuel tank arranged with its axis substantially horizontal, two holes at each end of the tank in its upper surface, a float valve positioned at each end of the tank adjacent the two holes thereat, the two holes at each end being connected at different vertical levels to a chamber of each float valve, the float valve having a passage controlled by a closure member, the passage being connected by a branch tube to a similar branch tube connected to the float valve at the other end of the tank, the branch tubes being connected to a normally closed control valve which under a slight over-pressure in the tank permits the passage of vapor through the control valve, and which opens to admit air from the atmosphere when there is an under-pressure in the tank, the control valve being connected by a tube to a fuel vapor trap, the trap being connected to a source of filtered air for purging of the trap and being connected to an air intake of the vehicle engine to receive the purging air leaving the trap, the float valves being located at a level above the tank such that the float valves are open when the vehicle is stationary and substantially horizontal, each float valve passage having a substantially vertical portion and the closure member being mounted for movement in a substantially vertical direction in that passage, the float member being attached to an arm of a lever mounted for rocking movement about a substantially horizontal pivot fixed in the chamber of the float valve, the rocking lever having a second arm to which is attached a float member.
Claim 2
Dependent Claim 281 words
A motor vehicle having an elongated fuel tank arranged with its axis substantially horizontal, two holes at each end of the tank in its upper surface, a float valve positioned at each end of the tank adjacent the two holes thereat, the two holes at each end being connected at different vertical levels to a chamber of each float valve, the float valve having a passage controlled by a closure member, the passage being connected by a branch tube to a similar branch tube connected to the float valve at the other end of the tank, the branch tubes being connected to a normally closed control valve which under a slight over-pressure in the tank permits the passage of vapor through the control valve, and which opens to admit air from the atmosphere when there is an under-pressure in the tank, the control valve being connected by a tube to a fuel vapor trap, the trap being connected to a source of filtered air for purging of the trap and being connected to an air intake of the vehicle engine to receive the purging air leaving the trap, the float valves being located at a level above the tank such that the float valves are open when the vehicle is stationary and substantially horizontal, each float valve passage having a substantially vertical portion and the closure member being mounted for movement in a substantially vertical direction in that passage, the float member being attached to an arm of a lever mounted for rocking movement about a substantially horizontal pivot fixed in the chamber of the float valve, the rocking lever having a second arm to which is attached a float member.
Claim 3
Dependent Claim 248 words
In a motor vehicle having a liquid fuel tank provided with a vapor ventilation means, a fuel vapor trap connected by a tube to the ventilation means, purging means for passing air through the trap, an engine to which the purging air is fed, and normally closed valve means connected between the ventilation means and the vapor trap to control the communication of the tank with the atmosphere, the improvement in the vapor ventilation means comprising: a. conduit means connected to openings in the upper wall of the tank in at least two remotely spaced positions, said openings being above the normal maximum level of fuel in the tank when the vehicle is stationary and substantially level; b. valve means positioned adjacent to each of said openings, each valve means including a valve housing, the interior of each valve housing being connected to one of said conduit means; c. a vapor outlet passage extending through an upper wall of said housing and connected to said tube; d. a valve seat in said passage; e. a valve closure member movable in said passage to abut said seat and close said passage; and f. a float member movably contained in said housing and operatively connected to said valve closure member and located above said normal fuel level, whereby inflow of liquid fuel through each of said conduit means to said housing acts on said float member to close said valve passage to prevent flow of liquid fuel through said tube.
Claim 4
Dependent Claim 248 words
In a motor vehicle having a liquid fuel tank provided with a vapor ventilation means, a fuel vapor trap connected by a tube to the ventilation means, purging means for passing air through the trap, an engine to which the purging air is fed, and normally closed valve means connected between the ventilation means and the vapor trap to control the communication of the tank with the atmosphere, the improvement in the vapor ventilation means comprising: a. conduit means connected to openings in the upper wall of the tank in at least two remotely spaced positions, said openings being above the normal maximum level of fuel in the tank when the vehicle is stationary and substantially level; b. valve means positioned adjacent to each of said openings, each valve means including a valve housing, the interior of each valve housing being connected to one of said conduit means; c. a vapor outlet passage extending through an upper wall of said housing and connected to said tube; d. a valve seat in said passage; e. a valve closure member movable in said passage to abut said seat and close said passage; and f. a float member movably contained in said housing and operatively connected to said valve closure member and located above said normal fuel level, whereby inflow of liquid fuel through each of said conduit means to said housing acts on said float member to close said valve passage to prevent flow of liquid fuel through said tube.

References Cited (Backward Citations)

US2414158A Cited
US3542239A Cited
US3554175A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1975-08-22 1976-02-21 1976-08-22 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1979-08-22 1980-02-21 1980-08-22 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1983-08-22 1984-02-21 1984-08-22 $7700.00 Window Closed / Lapsed

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