Internal-combustion engines – Charge forming device – Fuel flow regulation between the pump and the charge-forming...
Reexamination Certificate
1999-10-29
2001-04-10
Moulis, Thomas N. (Department: 3747)
Internal-combustion engines
Charge forming device
Fuel flow regulation between the pump and the charge-forming...
C174S151000, C439S936000
Reexamination Certificate
active
06213101
ABSTRACT:
BACKGROUND OF THE INVENTION
1. Technical Field
The present invention relates generally to a method and apparatus for blocking fluid and fuel vapors. More particularly, the present invention relates to a unique method and construction of an apparatus for preventing fluid leakage and vapor migration through the use of electrical wires.
2. Discussion
Conventional automotive fuel delivery systems utilize an electric fuel pump mounted in a fuel tank to deliver fuel from the fuel tank to the engine. Power is supplied to the fuel pump through electric wires connected between the fuel pump and a voltage source such as an alternator or a vehicle battery. In order to reach the fuel pump, the electrical wires must pass through an opening in the fuel tank. Such an opening, unless properly sealed, potentially provides a pathway for fluid leakage and fluid vapor migration commonly referred to as vapor permeation. Minimizing such fluid leakage and vapor permeation is desirable due to increasing regulations regarding automotive fuel vapor emissions and overall product efficiency.
Several attempts to seal this opening in the fuel tank have been developed. Many of these contributions to the art include a bushing or a fitting adapted for placement in the opening. The electrical wires then pass through this bushing or fitting. Although the wires are fitted together as tightly as possible through the bushing or fitting, spaces or pores inevitably exist through which fluid leakage and vapor permeation is released.
In other contributions to the art, fluid leakage and vapor permeation is attempted to be prevented through the use of numerous continuous wires, the center portions of which are stripped of insulation. A plug is then placed over the exposed center insulation stripped wire portion. The entire composite is then blocked through a chemical bath treatment. Such a contribution is illustrated in U.S. Pat. No. 5,631,445 (Herster). Such contributions typically include production processes which are laborious and expensive, further possibly requiring separate internal and external harnesses. Moreover, the use of insulated continuous wire is rather costly and wasteful since this high end type of wire is only required in the area inside the fuel tank and not throughout the entire vehicle. Wires in the fuel tank are typically specially cured such as through chemical baths or through exposure to radiation to strengthen their various necessary attributes. This greatly increases the cost of the wires.
As set forth above, in order to maintain electrical integrity, the electrical wires are typically wrapped with expensive insulation. Some such wire insulation swells when exposed to fluid or vapor permeation which may cause cracking and/or breakage. Other types of insulation shrink when exposed to fluid or vapor permeation, thus increasing the size of the pathway through which fluid leakage or vapor permeation may escape. When the insulation on the wires passing through a fitting deteriorates due to shrinking or swelling, or when the wires are not sufficiently bound to the fitting, the area between the wire and the fitting are widened providing a greater pathway through which fluid leakage or vapor permeation may be released.
In other processes, the center of the conductors is stripped and through a vacuum process, a fuel resistant sealant is introduced to fill the pores between the wires and the fitting. New wire is also being developed which includes a blocking agent added during the extrusion process.
The current contributions to the art do not effectively compensate for the problems set forth above, in part by failing to adequately seal and close the space between the wires and the fitting, and by failing to sufficiently bond the wires to the fitting. In order to overcome the problems associated with the current contributions to the art, various designs and methods for blocking fluid and fuel vapors have been developed. The continued development has been directed to designs which simplify the manufacturing process and assembly while keeping costs at a minimum and performance at a maximum.
SUMMARY OF THE INVENTION
It is a principal object of the present invention to provide a method and apparatus for blocking fluid and fuel vapors which eliminates the minute pathways from which fluid leakage and vapor permeation may escape. The term “fluid” will be used throughout, however, it will be appreciated that this term includes both fluid and vapor.
A related object of the present invention is to provide a method and apparatus for blocking fluid and fuel vapors which allows for the use of a solid wire inside the fuel tank and a more cost effective wire outside the fuel tank.
It is another object of the present invention to provide a method and apparatus for blocking fluid and fuel vapors which includes welding two separate wires together forming one continuous wire, wherein a consistent, solid barrier is created within the weld. This welded section is then overmolded with a fuel resistant plastic resin.
It is still yet another object of the present invention to provide a method and apparatus for blocking fluid and fuel vapors which is inexpensive to manufacture and easy to install.
It is another object of the present invention to provide a method and apparatus for blocking fluid and fuel vapors which does not require the laborious and costly process of dipping the wires into a chemical bath.
It is another object of the present invention to provide a method and apparatus for blocking fluid and fuel vapors that utilizes a more costly, solid, insulated wire inside the fuel tank and a more cost effective automotive grade wire outside the fuel tank.
In one form, the present invention provides a method for blocking fluid and fuel vapors including electrical wires. The method of the present invention includes the general steps of cutting an electrical wire and stripping the wire of its insulation at the cut ends. The wires are then bonded back together through the use of welding. The term “welding” will be used throughout, however, it will be appreciated that any commonly known bonding or adhering means may be utilized including, but not limited to, soldering, ultra sonic welding, resistance welding, tungsten-inert gas (hereinafter “TIG”) welding, or gas metal arc welding. Finally, this welded section, plus a portion of the wire insulation is overmolded with a fuel resistant plastic resin.
In another form, the present invention provides an apparatus for blocking fluid and fuel vapors including electrical wires which are cut and stripped of their insulation at the cut ends. The wires are then bonded back together through the use of welding. The welded section, plus a portion of the wire insulation, is then overmolded with a fuel resistant plastic resin.
REFERENCES:
patent: 3308316 (1967-03-01), Pfahl
patent: 4012282 (1977-03-01), Hutter et al.
patent: 4061344 (1977-12-01), Bradley et al.
patent: 4104484 (1978-08-01), Ijlstra et al.
patent: 4107456 (1978-08-01), Schuster et al.
patent: 4213004 (1980-07-01), Acker et al.
patent: 4492421 (1985-01-01), Ito
patent: 4599487 (1986-07-01), Blank et al.
patent: 4982055 (1991-01-01), Pollack et al.
patent: 5194697 (1993-03-01), Hegner et al.
patent: 5278357 (1994-01-01), Yamanashi
patent: 5406032 (1995-04-01), Clayton et al.
patent: 5596176 (1997-01-01), Everitt
patent: 5631445 (1997-05-01), Herster
Numbers James W.
Nye John
Tilli George J.
Zaima Harold H.
Harness Dickey & Pierce PLC
Moulis Thomas N.
LandOfFree
Method and apparatus for blocking fluid and fuel vapors does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Method and apparatus for blocking fluid and fuel vapors, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Method and apparatus for blocking fluid and fuel vapors will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-2498192