Towable auxiliary fuel tank

A towable, auxiliary fuel tank designed to transport a supply of fuel, so that a towing vehicle is able to consume the fuel present in the tank, thus extending the range of the vehicle. A ring is affixed to the trailer of the tank so that it may be connected to a vehicle. Attached to the vehicle is a hitch with a channel extending across a recess and a pin slidably mounted therein. The recess of the hitch is designed to hold the ring when the pin is closed, thus connecting the auxiliary tank to the vehicle. A lever is attached to the pin so that the ring may be connected and disconnected from the hitch. A cable is also attached to the pin and extends to a handle within the interior of the vehicle. When this handle is operated, the pin is moved from across the recess, thus unlocking the auxiliary tank from the vehicle. Fuel is transported from the auxiliary tank to the vehicle via a hose that is connected to both the auxiliary tank and vehicle. A securing device is provided to secure the hose to the vehicle. Furthermore, this securing device allows the hose to be disconnected from the vehicle when the auxiliary tank and vehicle are disconnected by operation of the handle.

BACKGROUND OF THE INVENTION 
1. Field of the Invention 
This invention relates to a system for providing an auxiliary fuel supply 
for motor vehicles that are capable of pulling trailers. More 
specifically, this invention relates to an auxiliary fuel supply and 
transfer system for a tank or other military vehicle that is capable of 
towing a fuel tank. 
2. Discussion of Background 
Military tanks and Bradley Fighting Vehicles (hereinafter vehicle) normally 
include either gasoline or diesel engines and a corresponding internal 
fuel tank. However, these internal fuel tanks are limited in size, because 
they must be protected within the skin of the vehicle. These vehicles are 
generally used during offensive or attack maneuvers and require large 
quantifies of fuel to continue their onslaught. During breaks in these 
maneuvers, the vehicles must be refueled, or risk running out of fuel and 
thus severely limiting both offensive and defensive capabilities. Another 
disadvantage of the limited internal fuel tank is the relatively low range 
the vehicles may travel without refueling. 
Several systems have been developed for supplying or transporting 
additional fuel for a vehicle. In U.S. Pat. Nos. 2,376,336 and 2,354,438, 
Brown and Craig, respectively, recognize the problem and provide quick 
release fuel tanks that are strapped externally to the military vehicles. 
When the vehicles run low on fuel, the fuel within the external tanks is 
introduced into the internal tanks, thus refueling the vehicle. 
Furthermore, if the vehicle encounters combat or other dangerous 
situations, the external tanks can be released, thus removing a possible 
explosion source from the vehicle. Although the fuel tanks can possibly be 
retrieved later, the fuel is consumed by the vehicle when it is eventually 
transferred into the internal fuel tank of the vehicle. 
In U.S. Pat. No. 3,677,284, Mendez discloses a Fuel Transfer System For 
Tractor Trailer Vehicles. In this system, the tractor tows an additional 
source of fuel present in an external tank on the trailer. The source of 
fuel for the tractor, its internal fuel tank or the external fuel tank, 
can be alternated from within the tractor. However, Mendez lacks the 
capability of releasing the external fuel supply from within the vehicle 
during an emergency or otherwise dangerous situation. Therefore, there 
remains a need for a fuel transfer system that permits the towing vehicle 
to consume the towed fuel, while having an emergency means of disengaging 
the external supply of fuel if a dangerous situation arises. 
SUMMARY OF THE INVENTION 
According to its major aspects and broadly stated, the present invention is 
a towable auxiliary fuel tank. The auxiliary fuel tank is designed to 
carry a supply of fuel and be towed behind a vehicle while the vehicle 
consumes the fuel within the tank, thus extending the range of the 
vehicle. 
The auxiliary fuel tank comprises a trailer with at least one pair of 
wheels and an axle so that it may be transported easily. A fuel container 
is positioned on the frame having a towing ring, thus enabling the 
auxiliary fuel tank to connect to a hitch positioned on the rear of a 
vehicle. Furthermore, the fuel container may be coated with a protective 
armored surface or specifically shaped to deflect small arms fire. 
The hitch is generally rectangular in shape with a recess formed therein. 
The recess has a protrusion extending away from the rear of the vehicle 
that causes the end of the hitch proximate to the auxiliary fuel tank to 
form a bulb. The opening of the recess is dimensioned and contoured so 
that the ring slides easily into and out of the recess and does not bind 
when the auxiliary fuel tank is being towed. 
A channel is formed within the hitch which extends from the end attached to 
the vehicle, through the length of the hitch, across the recess, and into 
the bulb. A pin fits within this channel and can slide between a closed 
position wherein the pin extends across the opening of the recess into the 
bulb, and an open position, wherein the pin is withdrawn into the hitch, 
thus clearing the opening of the recess. The pin, in its closed position, 
is held securely by a ball detent within the channel. A lever extends from 
the pin through a slot in the side of the hitch, so that the pin may be 
manually moved between its open and closed positions. As the pin slides 
within the channel, the lever slides within the slot. 
The hitch is designed so that the auxiliary fuel tank and the vehicle may 
be connected and disconnected quickly and easily. The lever of the hitch 
serves as one means for manually locking and unlocking the ring in the 
recess. A second system of disengaging the auxiliary fuel tank from the 
vehicle is used during emergency situations. This system includes a cable 
attached to the pin within the channel of the hitch. The cable extends 
through the interior of the vehicle to a handle. When the handle is 
operated, the pin moves from the closed position to the open position, 
thus unlocking the ring from the recess of the hitch. 
The fuel within the auxiliary fuel tank is used first by the vehicle so 
that its internal fuel tank remains full. Then, the auxiliary fuel tank 
can be released and the vehicle drives forward on its internal fuel tank. 
One end of a hose is attached to the auxiliary fuel tank; the other end of 
the hose is connected to the vehicle. A valve within the vehicle is used 
to connect one of the two sources of fuel to the engine. For instance, if 
the auxiliary tank is disconnected from the vehicle, the engine will 
consume the fuel from the internal tank. An auxiliary fuel pump, carried 
by the trailer, may be provided to pump fuel into the vehicle's internal 
tank or a third vehicle's internal tank. 
In the preferred embodiment, to connect the hose to the nozzle on the 
vehicle, at least one spring clip is placed over the hose, thus pinching 
the hose about the nozzle. In this manner the hose is securely held about 
the nozzle, but will snap off if the auxiliary fuel tank is disconnected 
from the vehicle. In an alternative embodiment of the present invention, 
the fuel hose is also placed over a nozzle on the vehicle; however, a 
compression ring is placed around the hose over the nozzle. A sleeve is 
subsequently placed over the hose and compression ring. The sleeve has a 
cam device so that when it is in place, the cam compresses the compression 
ring about the hose, thus securing the fuel hose to the nozzle. A tether 
attached to the cam device actuates if the auxiliary fuel tank is released 
from the vehicle, thus disengaging the cam and compression ring, and 
subsequently releasing the hose from the nozzle. 
An important feature of the present invention is that the auxiliary towable 
fuel tank supplies a consumable source of fuel to a vehicle. The 
capability of the vehicle to consume the fuel from within the auxiliary 
fuel tank without consuming the fuel from its own internal tank extends 
the effective range of the vehicle. 
Another feature of the present invention is the emergency disconnect of the 
hitch. When the handle is operated from inside the vehicle, the auxiliary 
fuel tank is released. This serves as an important function if the vehicle 
enters a dangerous situation where towing an auxiliary fuel tank would be 
a liability, such as in a combat environment. If this situation occurs, an 
operator merely has to use the handle, thus releasing the auxiliary tank 
from the vehicle. 
Yet another feature of the present invention is the fuel hose and pump. The 
fuel hose and pump transfer fuel between the auxiliary fuel tank and the 
internal fuel tank of the vehicle, or possibly between the auxiliary tank 
and a third vehicle. 
Still another feature of the present invention is the spring clip and 
sleeve and compression ring for the securing the fuel hose to the vehicle. 
These devices, discussed in two separate embodiments above, allows the 
hose to be secured to the nozzle and subsequently removed from the towing 
vehicle when the handle is operated to disconnect the auxiliary fuel tank 
from the vehicle. 
Yet another feature of the present invention is the structure and coating 
of the auxiliary fuel tank. An armored coating and rounded surface help 
deflect small arms fire from penetrating the auxiliary fuel tank. It is 
necessary to protect the auxiliary fuel tank because an enclosed supply of 
fuel within the auxiliary fuel tank is a possible source of explosion, 
increasing the danger to the vehicle. 
Other features and advantages of the present invention will be apparent to 
those skilled in the an from a careful reading of the Detailed Description 
of a Preferred Embodiment presented below and accompanied by the drawings.

DETAILED DESCRIPTION OF A PREFERRED EMBODIMENT 
In the following description, similar components are referred to by the 
same reference numeral in order to simplify the understanding of the 
sequential aspect of the drawings. 
Referring now to FIGS. 1 and 2, a towable, auxiliary fuel tank 10 
(HEREINAFTER auxiliary fuel tank) is shown in conjunction with a military 
vehicle 12 (HEREINAFTER vehicle). Auxiliary fuel tank 10 is designed to 
carry a quantity of fuel and supply this fuel to vehicle 12, so that the 
internal fuel tank of vehicle 12 will remain full while vehicle 12 
consumes the fuel present in auxiliary fuel tank 10. This will not only 
increase the effective range of vehicle 12, but will also reduce the 
repeated stopping and refueling vehicle 12. It should also be noted that 
vehicle 12 is shown as a military tank, but could be any other military 
vehicle or civilian vehicle that would be served by auxiliary fuel tank 
10. 
Auxiliary fuel tank 10 comprises a trailer 24 with at least one pair of 
wheels 20 and a corresponding axle 22. A container 30 is also mounted to 
trailer 24, so that a quantity of liquid, namely fuel, can be transported 
by auxiliary fuel tank 10. A support 32 with a foot 36 is able to pivot 
about pivot point 34 to support tank 10 when it is not in use. Support 32 
is carried by trailer 24 and when auxiliary fuel tank 10 is being 
transported, support 32 pivots out of the way, so that it extends parallel 
with trailer 24. Trailer 24 also comprises a ring 40, thus enabling 
auxiliary fuel tank 10 to be connected to vehicle 12. Ring 40 is annular 
in shape and extends from trailer 24, so that ring 40 lies in a plane 
parallel to trailer 24. 
Container 30 is approximately rounded and coated with a protective surface 
to deflect small arms fire, including relatively small caliber weapons. A 
suitable protective surface would be armor plating or merely an extra 
thickness of steel that is provided to prevent small arms fire from 
penetrating container 30. Typically, container 30 will be transporting a 
supply of fuel and any puncture and subsequent spark is likely to cause an 
explosion, thus increasing the danger associated to vehicle 12. Therefore, 
in a military type setting it is necessary to provide the container with 
suitable protection. However, with most non-military operations, the 
protective coating would not be required as the danger of small arms fire 
is greatly reduced. 
Referring now to FIGS. 2-4, to connect auxiliary fuel tank 10 to vehicle 
12, ring 40 attaches to a hitch 50 on the rear of vehicle 12. Hitch 50 has 
a first end 52 and a second end 54. A base plate 56 is attached to second 
end 54 and is typically affixed to the rear of vehicle 12. Base plate 56 
can be attached to vehicle 12 in any suitable manner known to those 
skilled in the art, including bolts or welds, so that hitch 50 and vehicle 
12 is capable of towing auxiliary fuel tank 10. 
Hitch 50 is generally rectangular in shape, having a bottom 58, a top 60, 
and as stated above, first end 52 and second end 54. Hitch 50 also has a 
recess 64 formed therein. Recess 64 enters hitch 50 from its bottom 58 
proximate to first end 52 and extends within hitch 50 towards top 60. 
Recess 64 also has a protrusion 70 that extends towards first end 52 
within hitch 50. A neck 68 is formed near top 60 of hitch 50 by recess 64 
and protrusion 70. Recess 64 and protrusion 70 also form a bulb 72 from 
first end 52 of hitch 50. Bulb 72 extends from neck 68, thus forming an 
opening 66 in recess 64. Hitch 50 is designed so that ring 40 can fit 
within opening 66 and subsequently rest in protrusion 70 of recess 64, 
when auxiliary fuel tank 10 is being towed by vehicle 12. 
Additionally, hitch 50 has a channel 76 proximate to bottom 58 extending 
from second end 54, across opening 66 of recess 64, into bulb 72. Channel 
76 has a generally circular cross-section and a diameter smaller than the 
thickness of hitch 50. A pin 80 is slidably mounted within channel 76. Pin 
80 is in a closed position when pin 80 extends across opening 66 and 
penetrates bulb 72, thus effectively closing recess 64 and capturing ring 
40, as best illustrated in FIG. 4. Pin 80 is in an open position when pin 
80 is withdrawn into hitch 50, so that it does not extend across opening 
66. In this open position, as best seen in FIG. 2, ring 40 is designed to 
pass through opening 66 into and out of recess 64. Once ring 40 is within 
recess 64 and pin 80 is in the closed position, ring 40 has sufficient 
room to pivot, rotate, or otherwise move within recess 64, so that as 
auxiliary fuel tank 10 is being towed, ring 40 does not bind within recess 
64. 
Pin 80 has a lever 82 extending perpendicular from its length and which 
serves as a manual device for moving pin 80 between its open and closed 
positions. Lever 82 extends from pin 80 through a slot in the side of 
hitch 50, so that as pin 80 is moved between its two positions, lever 82 
slides within slot 84. Pin 80 is retained in its closed position within 
channel 76 by a ball detent 86. The ball detent 86 is typical to what is 
known to those skilled in the art and is generally comprised of at least 
one ball that is spring biased within pin 80 so that the ball forms a 
"bump". Channel 76 typically will have a "dent" within its walls so that 
as the ball is biased toward the channel, the ball will seat itself into 
the "dent", thus securing itself. Other types of ball detent means are 
known and apparent to those skilled in the art and, as such, are within 
the scope of this disclosure. 
A cable 90 is attached to pin 80 within channel 76. Cable 90 extends 
through channel 76, through second end 54 and into vehicle 12. Once inside 
vehicle 12, cable 90 travels through a series of pulleys or guides 94 
until it reaches the interior compartment of vehicle 12. At this point, 
cable 90 is connected to a handle 92 so that when handle 92 is operated, 
pin 80 moves from its closed to its open position, thus unlocking ring 40 
from hitch 50. Handle 92 provides the second system for disengaging 
auxiliary fuel tank 10 from vehicle 12, as lever 82 can also be manually 
operated to pin 80 between its two positions. 
It should also be noted that it is contemplated that a safety pin or other 
suitable device will be inserted proximate to handle 92, once pin 80 is in 
the closed position. The safety pin will eliminate the possibility of 
prematurely or inadvertently releasing pin 80. Thus to operate handle 92, 
the safety pin would have to be removed before pin 80 could be moved to 
the closed position. 
In operation, auxiliary fuel tank 10 is typically attached to vehicle 12 
manually by lever 82. In a non-emergency situation, auxiliary fuel tank 10 
can also be disconnected from vehicle 12 by lever 82. However, during an 
emergency situation where it is necessary to discard auxiliary fuel tank 
10 quickly and when vehicle 12 and auxiliary fuel tank 10 are in motion, 
handle 92 can be operated from within vehicle 12, thus moving pin 80 from 
the closed position and unlocking ring 40. In the open position, ring 40 
will effectively fall through opening 66 of recess 64, thus disengaging 
auxiliary fuel tank 10 from vehicle 12. 
It should be also noted that other means, including electronically actuated 
devices, could replace handle 92 and be used to move pin 80 from its 
closed to open position. These modifications are anticipated and therefore 
are within the scope of this disclosure. 
As described above, auxiliary fuel tank 10 supplies vehicle 12 with an 
external supply of fuel when auxiliary fuel tank 10 is being towed by 
vehicle 12. A hose 100 transports fuel between auxiliary fuel tank 10 and 
vehicle 12, as best seen in FIG. 2. When handle 92 is operated, unlocking 
ring 40 from hitch 50 and releasing auxiliary fuel tank 10 from vehicle 
12, hose 100 is approximately simultaneously released from vehicle 12, as 
will be described in detail below. 
Hose 100 is affixed to container 30 through a connector 102 and possibly 
could be affixed to a pump 104. Connector 102 merely provides a fluid 
connection between the interior of container 30 and hose 100. Pump 104 is 
not necessarily required to pump fuel between auxiliary fuel tank 10 and 
vehicle 12, because an interior fuel pump on vehicle 12 may provide the 
necessary pressure to transfer the fuel. Pump 104, typically an auxiliary 
electric fuel pump, is essentially provided to transfer fuel from within 
container 30 of auxiliary fuel tank 10 to a third vehicle or, if 
necessary, to top off the internal fuel tank of vehicle 12 
Hose 100 is connected to vehicle 12 in a manner that permits it to be 
disconnected quickly and easily. If auxiliary fuel tank 10 is released 
from vehicle 12 during an emergency situation as described above, hose 100 
must be able to be released from vehicle 12 just as quickly. Vehicle 12 is 
supplied with a nozzle 110 that permits fuel within hose 100 to be 
consumed by vehicle 12. Nozzle 110 is a basic fluid connection port that 
has a series of raised ridges 114 that permit hose 100 to be easily slid 
onto nozzle 110, but requires greater difficulty to remove hose 100 from 
nozzle 110. Furthermore, nozzle 110, as illustrated in FIGS. 5-8, is 
connected to a fuel line 112 in vehicle 12. Fuel flows through hose 100, 
into nozzle 110, and into fuel line 112, so that vehicle 12 consumes the 
fuel present in auxiliary fuel tank 10. A valve 116, that determines the 
source of fuel vehicle 12 consumes, is positioned within fuel line 112. 
If, for instance, auxiliary fuel tank 10 is released from vehicle 12, 
valve 116 would be actuated to close fuel line 112, and vehicle 12 would 
consume fuel from its internal fuel tank. 
In a preferred embodiment of the present invention, as illustrated in FIGS. 
5 and 6, at least one spring clip 122, preferably more, is used to secure 
hose 100 to nozzle 110. In operation, at least one spring clip 122 is 
slipped over hose 100. Hose 100 is subsequently fitted about nozzle 110. 
Spring clip 122 is compressed so that its internal cavity enlarges, and is 
then slid over hose 100 and nozzle 110. Spring clip 122 is positioned 
between a pair of ridges 114, and when spring clip 122 is subsequently 
released, its internal cavity contracts about hose 100 and nozzle 110, 
thus securing hose 100 to nozzle 110. During an emergency situation, when 
auxiliary fuel tank 10 is unlocked and released from vehicle 12, the 
weight and force of auxiliary fuel tank 10, slowing down relative to 
vehicle 12, snaps hose 100 and spring clip 122 from nozzle 110. 
An alternative embodiment for securing hose 100 to nozzle 110 is shown in 
FIGS. 7 and 8. In this alternative embodiment, a compression ring 128 and 
a sleeve 130 having a first end 132 and a second end 134 that work in 
conjunction to secure hose 100 to nozzle 110. Sleeve 130 is generally a 
hollow cylinder where first end 132 has a larger interior and exterior 
diameter than second end 134. Within the radial surface and extending 
through sleeve 130 is a hole 136. Positioned proximate to hole 136 and 
within the interior of sleeve 130 is a rib 138. Rib 138 is an indentation 
within the interior of sleeve 130 having a smaller inner diameter than the 
surrounding diameter of sleeve 130. Positioned adjacent to hole 136 and 
proximate to first end 132 is a holder 140. Holder 140 is a U-shaped 
member designed to support a cam 144 and a cam lever 146 about a pivot 
142. Pivot 142 is a pin extending through cam 144 and the legs of holder 
140. Cam 144 is dimension and contoured so that as it pivots about pivot 
142, cam 144 extends through hole 136 within the interior of sleeve 130. 
Cam lever 146 is an extension attached to cam 144 and is designed to help 
cam 144 pivot about pivot 142. 
To engage the alternative embodiment, sleeve 130 is first placed over hose 
100 and then compression ring 128. Hose 100 is subsequently fitted over 
nozzle 110 of vehicle 12 and compression ring 128 is slid over hose 100 
and nozzle 110, positioning it between a pair of ridges 114. Sleeve 130 is 
then slid over compression ring 128, hose 100, and nozzle 110, so that 
hole 136 is aligned over compression ring 128. Hole 136 will automatically 
align over compression ring 128 because rib 138 will engage compression 
ring 128 as sleeve 130 is slid over hose 100 and nozzle 110. This 
engagement ceases the movement of sleeve 130 about hose 100 and nozzle 
110, thus aligning hole 136 over compression ring 128 consistently. Cam 
144 is then pivoted so that as cam 144 extends through sleeve 130, cam 144 
presses down and subsequently compresses compression ring 128 about hose 
100 and nozzle 110. 
A tether 150 is attached to cam lever 146 at one end and to auxiliary fuel 
tank 10 at its other end. During an emergency situation, when handle 92 is 
operated and auxiliary fuel tank 10 is released from vehicle 12, cam 144, 
sleeve 130, and compression ring 128 release hose 100 from nozzle 110. As 
auxiliary fuel tank 10 is released it begins to drop back with respect to 
vehicle 12, and as it does tether 150 is tightened. This tension operates 
cam lever 146 and pivots cam 144 so that the pressure is released from 
compression ring 128, thus permitting hose 100 to be snapped off nozzle 
110. As in the preferred embodiment, when vehicle 12 is without auxiliary 
fuel tank 10 and an external source of fuel, vehicle 12 begins to consume 
the fuel in its internal tank. 
It will be apparent to those skilled in the art that many changes and 
substitutions can be made to the preferred embodiment herein described 
without departing from the spirit and scope of the present invention as 
defined by the appended claims.