Fuel Tank with Internal Bladder and Method

Abstract

A fuel tank for a generator or the like, wherein the fuel tank includes a rigid outer fuel tank structure and an inner bladder. The outer fuel tank structure includes a longitudinal channel for receiving the inner bladder. End caps are disposed on either end of the outer fuel tank structure, so that the internal bladder may be pulled therein with cables or the like. When the internal bladder needs to be replaced due to damage or corrosion, the end caps are removed and cables may be attached to one end of the damaged internal bladder for pulling it from the outer fuel tank structure. Additionally, a replacement bladder may be attached via cables to the other end of the damaged bladder, so that the replacement bladder is pulled into one end of the outer fuel tank structure while the damaged bladder is being pulled out the other end thereof.

Claims

1. A fuel tank assembly comprising: an enclosed rigid outer fuel tank formed into a longitudinal structure including a series of support members, wherein said outer fuel tank includes a longitudinal channel for receiving an internal bladder and a pair of removable end caps that are disposed on opposed ends of thereof; a removable, collapsible internal bladder positioned within said longitudinal channel within said outer fuel tank; wherein said internal bladder may be removed from or inserted into said outer fuel tank through either end thereof when one or both end caps have been removed.

2. The fuel tank assembly set forth in claim 1, further comprising a pair of pull cables, wherein said pull cables are attached to each longitudinal side of said internal bladder.

3. The fuel tank assembly set forth in claim 1, wherein said outer fuel tank and said internal bladder both include fuel ports that are in operative communication with one another so that a user may fill said internal bladder through said fuel ports.

4. The fuel tank assembly set forth in claim 3, wherein said fuel port on said outer fuel tank is connected to said fuel port on said internal bladder by a fuel line.

5. The fuel tank assembly set forth in claim 4, wherein said fuel line is connected to said outer fuel tank by a quick connect assembly.

6. The fuel tank assembly set forth in claim 4, wherein said fuel line is connected to said internal bladder by a quick connect assembly.

7. The fuel tank assembly set forth in claim 1, further including a liquid sensor disposed within said outer fuel tank to detect the presence of a liquid substance within said outer fuel tank.

8. The fuel tank assembly set forth in claim 1, wherein said internal bladder comprises a bottom portion and a top portion that are joined together to form an enclosed space for receiving fuel.

9. The fuel tank assembly set forth in claim 1, further including a small steel primary disposed within said outer fuel tank to detect the fuel level within said internal bladder.

10. The fuel tank assembly set forth in claim 1, wherein said internal bladder is made from a nylon fabric having a polyether based polyurethane coating.

11. A method for replacing an internal bladder in a fuel tank assembly, said method comprising the steps of: providing an enclosed rigid outer fuel tank having a longitudinal channel for receiving and containing an internal bladder, and further including a pair of removable end caps disposed on opposed ends thereof; providing a first internal bladder for storing fuel, said first internal bladder being positioned within said longitudinal channel within said outer fuel tank; removing said end caps from both ends of said outer fuel tank; attaching a second internal bladder to said first internal bladder at one end of said first internal bladder; and pulling said first internal bladder out of said outer fuel tank through a first end thereof while said second internal bladder is simultaneously being pulled into said outer fuel tank at a second end thereof.

12. The method set forth in claim 11, further including the step of using a pair of pull cables to attach said first internal bladder to said second internal bladder.

13. The method set forth in claim 12, further including the step of using said pull cables to pull said first internal bladder out of said outer fuel tank at a first end thereof while simultaneously pulling said second internal bladder into said outer fuel tank at a second end thereof.

14. The method set forth in claim 13, further including the step of attaching said pair of pull cables to said first and second internal bladders so that one pull cable is attached along one longitudinal side of each bladder, and so that said second pull cable is attached along an opposed longitudinal side of each bladder.

15. The method set forth in claim 11, further including the step of reattaching said end caps to each end of said outer fuel tank after said second internal bladder is disposed within said longitudinal channel of said outer fuel tank.

16. The method set forth in claim 11, further including the step of detaching said first internal bladder from said second internal bladder after said second internal bladder is disposed within said longitudinal channel of said outer fuel tank.

17. The method set forth in claim 11, wherein said internal bladder is made from a nylon fabric having a polyether based polyurethane coating.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0032] These and other features, aspects, and advantages of the present invention will become better understood with regard to the following description, appended claims, and accompanying drawings where:

[0033] FIG. 1 is a perspective view of one embodiment of a fuel tank assembly having an internal bladder in accordance with the present invention, wherein a generally rectangular shaped rigid outer fuel tank includes a series of cross-support members that are shaped to form an arch, which provides a longitudinal channel through the center of the fuel tank for receiving an internal, removable bladder that is used to contain fuel;

[0034] FIG. 2 is an exploded perspective view showing the fuel tank assembly of FIG. 1, and further showing removable end caps that are attachable to either end of the rigid outer tank, an internal bladder having a generally flat bottom portion and a top portion that is generally arched to that it may slide into either end of the outer fuel tank, and further showing inset drawings of a control box attached to the outer fuel tank and a fuel port for filling the internal bladder with fuel;

[0035] FIG. 3 is an end view of one embodiment of the fuel tank assembly, showing the outer fuel tank and an internal bladder positioned within the outer fuel tank, and wherein a fuel port positioned on the outer fuel tank is operatively connected to the internal bladder by a hose or tube;

[0036] FIG. 4 is a top view of one embodiment of the fuel tank assembly, showing the outer fuel tank and an internal bladder positioned within the outer fuel tank.

[0037] FIG. 5 is a perspective view of one embodiment of a fuel tank assembly having an internal bladder in accordance with the present invention, wherein a generally rectangular shaped rigid outer fuel tank includes a series of cross-support members that are rectangular in shape for receiving an internal, removable bladder that is used to contain fuel; and

[0038] FIG. 6 is an exploded perspective view showing the fuel tank assembly of FIG. 5, and further showing removable end caps that are attachable to either end of the rigid outer tank, an internal bladder having a generally flat bottom portion and a top portion that is generally arched to that it may slide into either end of the outer fuel tank, and further including a small steel primary to be connected to the internal bladder.

DETAILED DESCRIPTION OF THE INVENTION

[0039] Overview

[0040] The present invention is a fuel tank assembly 10 includes, in a first embodiment as shown in FIGS. 1-6, a rigid outer fuel tank 12 that is generally rectangular shaped, and includes a series of cross-support members 14 to provide structural support for placement of a generator on an upper surface or platform 16 of the outer fuel tank 12. The cross-support members 14 each include an arch shape on an underside thereof, as shown in FIGS. 1-3, or a rectangular shape, as shown in FIGS. 4-6, which provides a longitudinal channel through the center of the outer fuel tank 12 for receiving an internal, removable bladder 18 that is used to contain fuel.

[0041] The Fuel Tank Structure

[0042] The outer fuel tank 12 structure, as briefly described above, essentially includes an enclosed rectangular structure with a flat base member 20 and upper surface 16, along with sufficient support members 14 to support a generator or the like on the upper platform 16 of the fuel tank. The support members 14 are preferably arched, as shown in FIGS. 1-3, if the fuel tank assembly is supported by the top of the outer fuel tank 12 to provide a longitudinal channel for receiving the internal, removable bladder 18 within the outer fuel tank 12. Alternatively, the support members 14 are preferably rectangular, as shown in FIG. 4-6, if the fuel tank assembly is supported by the side rails of the outer fuel tank 12. Removable end caps 22 are attached to either end of the outer fuel tank 12, and the outer fuel tank 12 itself is sealed and watertight, in order to prevent any liquid fuel from leaking out of the outer fuel tank 12 structure.

[0043] The outer fuel tank 12 includes at least one, and preferably at least two fuel ports 24 for allowing fuel to be pumped into the internal bladder 18, as shown in FIG. 3. Liquid sensors (not shown) may be positioned within the outer fuel tank 12, preferably in low-lying areas around the internal bladder 18, in order to detect any liquid that is present within the outer fuel tank 12 structure, and the sensors are operatively connected (either hardwired or wirelessly, as desired) to an alarm or notification system, optionally through a control box 26. If the sensors detect liquid in the outer tank 12 structure, then the sensors trigger an alarm or notification to personnel who are charged with monitoring the generator operations so that the problem may be investigated and resolved. Similarly, other types of sensors may also be used to detect fumes or gases that may be present within the outer tank structure, and alarms or notifications may be triggered, accordingly. Other types of sensors or mechanisms may be included within the internal bladder 18, including fuel level sensors, temperature sensors, and the like.

[0044] Access hatches or panels 50 may also be provided in strategic positions around the outer fuel tank, so that an inspector or maintenance worker may gain access to the internal space of the outer fuel tank 12 for purposes of maintenance and inspection, and to check for leaks or other problems, particularly if an alarm or notification is received from any of the sensors.

[0045] Small Steel Primary

[0046] In a preferred embodiment, a small steel primary 30 sits within the outer fuel tank 12 and is attached to an attachment point on the internal bladder 18 via a cam and groove coupling (or other means). The small steel primary 30 is intended to be used for housing a mechanical level gauge in order to determine the fuel level in the internal bladder 18. When the small steel primary 30 is attached to the internal bladder 18, a portion of the fuel enters the small steel primary 30. The small steel primary 30 includes a gauge and a float. The float travels vertically along the fuel level within the small steel primary 30, causing a helix located between the float and gauge to spin, which in turn causes the needle on the gauge to turn and indicate the fuel level. The internal bladder 18 will inflate and deflate during operation, changing where the top of the internal bladder 18 is located. The attachment of the small steel primary 30 creates a fixed point so that the gauge remains stationary. The small steel primary 30 is also used to prevent overfilling the internal bladder 18 by allowing excess fuel to flow into the small steel primary 30.

[0047] Internal Bladder

[0048] As noted in the documents that are incorporated herein by reference, there are many types of internal bladders in use commercially, and they are made from a variety of different materials. It should be understood that the present internal bladder 18 may be used using any suitable flexible material, but is preferably made with a nylon fabric having a polyether based polyurethane coating. This material is commercially available today from the Seaman Corporation, and the product is identified commercially as 1940 PTFF.

[0049] The internal bladder 18, in a preferred embodiment, includes a flat bottom portion that is heat-sealed or otherwise adhered and joined to a generally arched top portion, so that it may slide into the arched channel within the outer fuel tank 12 structure, as shown in FIGS. 1-3. The internal bladder 18 may also slide into a rectangular channel within the outer fuel tank 12 structure, as shown in FIGS. 4-6. The internal bladder 18 is preferably made from a flexible material, so that it is collapsible, particularly when it contains little or no fuel therein. The bladder 18 includes fuel ports 24 that are operatively connected with the fuel ports 24 on the outer fuel tank 12 via a fuel line 28 or the like. The fuel line 28 may be connected to the internal bladder 18 and/or the outer fuel tank 12 via a quick connect assembly in a preferred embodiment, and such quick connect assemblies are well known and commercially available. In one preferred embodiment, each side of the internal bladder includes a lip extending longitudinally along the sides of the bladder 18. The lip may further include a series of grommets or attachment points 32, so that a cable may be attached to the grommets via clips (or other means) and attached to each side of the bladder 18. As discussed above, the outer fuel tank 12 includes removable end caps 22 on each end thereof, so that the bladder 12 may be pulled into the outer fuel tank 12 by pulling the cables through the outer fuel tank 12 by running the cables into one end of the outer fuel tank 12 and out of the other end. In this way, the internal bladder 18 may be pulled into one end of the outer fuel tank 12 by the cables until the internal bladder 18 is properly situated between the end caps, as shown in FIG. 1 or 5. Thereafter, the cables may be removed or detached from the grommets, or the cables may simply be left attached to the internal bladder 18 and stored within the outer fuel tank 12 structure.

[0050] If the internal bladder 18 becomes damaged, corroded, or springs a leak, then cables may be attached to both the damaged inner bladder 18 and a new replacement bladder 18. In this way, as the damaged inner bladder 18 is being removed from one end of the outer fuel tank structure 12, the new replacement bladder 18 is being dragged into the outer fuel tank structure. Once the replacement bladder 18 is properly situated, then the damaged inner bladder 18 may be disconnected from the cables and properly disposed of or recycled, and the end caps may be placed back into the closed position on the outer fuel tank structure with the new replacement bladder contained therein.

[0051] Although the present invention has been described in considerable detail with reference to certain preferred versions thereof, other versions are possible. Therefore, the spirit and scope of the appended claims should not be limited to the description of the preferred versions contained herein. All features disclosed in this specification may be replaced by alternative features serving the same, equivalent or similar purpose, unless expressly stated otherwise. Thus, unless expressly stated otherwise, each feature disclosed is one example only of a generic series of equivalent or similar features.