Portable tanker-trailer heating system

A heating system for heating a tanker-trailer, including a housing, a fuel tank, a heating unit, fuel lines connecting the fuel tank to the heating unit, hot and cold water lines, connected at one end to the heating unit and at their other end to the tanker-trailer, and a control apparatus for controlling the flow of fuel from the fuel tank to the heating unit, water flow to and from the tanker-trailer, and the temperature of the water.

BACKGROUND OF THE INVENTION 
Tanker-trailers of the type which transport cargo often require that the 
cargo be maintained at a predetermined temperature. This does not present 
a problem for the carrier during the actual travel time spent with the 
cargo, as the trailer is equipped with a temperature control system which 
operates off the heating system of the tractor. 
During stop-overs, however, and those times when the trailer is 
disconnected from the tractor, the temperature maintenance noted above is 
not possible unless the tractor is maintained in contact with the trailer. 
This can result, in those cases where the cargo is a perishable food, in 
food spoilage. And in those cases where the tractor and trailer hook-up is 
maintained, just to provide for temperature control, an inefficient 
condition is created since the tractor is being used for a purpose for 
which it was not intended when it could be used for its intended purpose 
of transporting. 
It would, therefore, be desirable to have a way of maintaining the desired 
predetermined temperatures for the trailer and its cargo without having to 
use a tractor during the noted stop-overs. 
SUMMARY OF THE INVENTION 
It is an object of the present invention to provide a water heating system 
which is portable and adaptable for providing heat at a remote location. 
An object of the present invention, as it relates to tanker-trailers, is to 
provide a way to maintain a desired predetermined temperature for the 
tanker-trailers and their cargos without having to use a tractor. More 
specifically, this object of the present invention is to provide a system 
which can stand alone and be readily transported at, for example, a 
stop-over location. It is also a related object of the present invention 
to provide such a system as noted above which utilizes existing trailer 
systems for temperature control. 
These objects are achieved by the provision of a stand alone heating system 
including a heating unit which is connected to the remote location, such 
as a tanker-trailer. The heating system draws water from an external 
source, such as the tanker-trailer, or utilizes its own water supply, 
heats the water to a given temperature and returns it to the remote 
location, such as the tanker-trailer for circulation at the remote 
location, such as through the tanker-trailer water jacket system for 
heating the cargo. 
Neither the tractor nor the tanker-trailer need be modified in any way to 
achieve the above result as it applies to a tanker-trailer. It is only 
necessary to have the stand alone heating unit and a fuel supply connected 
to the heating unit. The heating unit is in turn connected to the remote 
location, such as the tanker-trailer and the process of heating the water 
and returning the heated water to the remote location, such as the 
tanker-trailer continues for as long as desired. 
The heating system is provided with a connecting apparatus for connecting a 
cold water line and a heated water line to the remote location, such as 
the tanker-trailer. It also includes a fuel reservoir with feed lines to 
the heating unit. Conveniently, the system comprises the heating unit, a 
water supply (optional), fuel reservoir, control panel and connecting 
apparatus housed in a mobil housing provided with wheels for readily 
moving the system at will. The control panel is provided with controls for 
controlling the flow of both water and fuel and for controlling the 
temperature of the water.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT 
A typical tanker-trailer 10 is shown disconnected from a tractor (not 
shown) in FIG. 1. The tanker-trailer 10 includes a tanker body 12 
supported by a set of wheels 14 and adjustable front support struts 16. As 
shown in FIG. 2 the tanker body 12 at its front end includes connections 
18 and 20 which represent inlet and return connections for the 
tanker-trailer water jacket system 22. This water jacket system is 
standard in tanker-trailers of the kind shown. 
As noted previously a means for heating the cargo contained in the 
tanker-trailer body 12 during transportation is readily achieved by the 
connection of the connections 18 and 20 of tanker-trailer body 12 with the 
tractor. However, when the tanker trailer 10 is disconnected from the 
tractor, as is the case in FIG. 1, the cargo in the tanker-trailer body 12 
is maintained at its desired temperature by the heating system according 
to the present invention. This heating system is shown and described in 
greater detail in FIGS. 3-6. 
Turning first to FIG. 3, there is shown in assembly a portable heating 
system 24 according to the present invention. The system includes a 
housing 26. The assembly is preferably portable and for this purpose the 
housing 26 is mounted on casters or wheels 28. A handle 30 is provided on 
the housing for manually moving the system assembly at will. Two of the 
components of the system are shown in FIG. 3 including a fuel tank 32 and 
a water tank and aeration system 34. The fuel tank 32 includes a capped 
fuel inlet 36, a fuel gauge 38 and a fuel drain valve 40. The water tank 
and aeration system 34 includes a tank body 42 mounted by support struts 
44 onto the housing 26. A capped water inlet 46 is provided on the top of 
the water tank 42. 
As seen in FIG. 4, the housing 26 has doors 48, 50 and 52 which open into 
an interior space 54 which houses all the components of the system except 
for the water and aeration system 34. The space 54 contains a heating unit 
56, a control box 58, the fuel tank 32 and a power supply source including 
a DC power supply 60 as well as a plurality of reserve batteries 62. The 
DC power supply 60 comprises an AC to DC converter which operates off of a 
standard AC source. In the event of a failure of the AC power source, the 
plurality of batteries 62 will provide the necessary power to operate the 
system. 
The heating unit 56 may be a unit manufactured by Webasto Thermosystems, 
Inc. and identified by the designation DBW 2010, which is a 45,000 Btu/hr 
unit. The heating unit 56 has a number of connecting points. Included is a 
cold water inlet port 64, a hot water outlet port 66, fuel inlet 
connecting port 68 to which a fuel feed line 70 is connected to the fuel 
tank 32, and a fuel return port 72 to which a fuel return line 74 is 
connected. 
The fuel tank 32 can be accessible through a door in the housing 26, or it 
may extend outwardly as shown in FIGS. 3 and 4. 
The system has two water lines, a cold water line 76 and a hot water line 
78. At one end the cold water line 76 is connected to the cold water inlet 
port 64, and the hot water line 78 is connected to the hot water outlet 
port 66. At their other end (not shown), the two water lines are connected 
to the connections 18 and 20 on the tanker-trailer body 12. At the control 
box 58, a cold water gauge line 80 is connected to a cold water 
temperature gauge 82 and to a sensor 84, and a hot water gauge line 86 is 
connected to a hot water temperature gauge 88 and to a sensor 90. In each 
water line there is provided a heat exchanger. A heat exchanger 92 is 
provided in the cold water line 76, and a heat exchanger 94 is provided in 
the hot water line 78. These heat exchangers serve as a source for 
checking and controlling the cold and hot water temperatures. 
The heat exchangers are preferably made of aluminum tube, caped at both 
ends, one end of each tube has a barbed hose adaptor 96 and a copper dry 
well 98 to insert a capillary bulb 100 (shown only in well 94) that senses 
water temperature and conveys it through a line 102 to a temperature 
control 104 for starting and stopping the combustion burner as needed to 
maintain constant water temperature. Water temperature can be controlled 
on the intake or outlet side of the heater, or both, depending upon the 
users needs or discretion. 
The capillary bulb is a standard Honeywell temperature controller, and can 
be purchased at any furnace supplier. 
The main power supply 60 is 12 volt Dc. The system incorporates a secondary 
battery backup 62 that can sustain normal operation of the unit for a 
specified amount of time, for example, up to 50 hours run time. 
The primary 12 volt Dc power supply is supplied by a 120 volt Ac to 12 volt 
Dc converter, which also maintains a 12 volt charge on the Dc battery. A 
12 volt Dc wet cell, gel cell or dry cell can be used. 
As shown in FIG. 5, the control panel 58 includes an on-off knob 106 for 
fuel flow and a meter 108 for indicating water flow. 
FIG. 6 illustrates the auxiliary water tank and aeration or air bleed off 
system 34. 
The system 34 is connected to the cold water line 76 by means of a brass 
pipe 110 through a T-connection 112. Any air trapped in the line 76 rises 
in the pipe. 
The water level is monitored through a sight tube 114 located on the side 
of the tank and refilled through the filler cap 46 on top of the tank 42. 
When a tanker-trailer, for example, is disconnected at an off-cite 
location, the lines 76 and 78 are connected to connections 18 and 20 and 
the system primed with water from the water jacket system 22, or from the 
water tank 42. The temperature is set to the desired level with the 
temperature selector 104 and the system started by turning the burner on 
with the on off knob 106. The temperatures are monitored at the heat 
exchangers and controlled to maintain the desired temperatures.