U.S. patent application number 11/051429 was filed with the patent office on 2005-08-04 for load management auxiliary power system.
Invention is credited to Kennedy, Gino.
Application Number | 20050167090 11/051429 |
Document ID | / |
Family ID | 46205465 |
Filed Date | 2005-08-04 |
United States Patent
Application |
20050167090 |
Kind Code |
A1 |
Kennedy, Gino |
August 4, 2005 |
Load management auxiliary power system
Abstract
An auxiliary power system for trucks, the power system having a
small diesel engine coupled to an air conditioner compressor and an
automotive style alternator. During hot weather the auxiliary
engine rotates the air conditioner compressor to provide cool air
to the truck and electrical power to truck accessories by load
management controls. When peak loads occur, the voltage is reduced
into the field of the alternator allowing the small engine to
simultaneously operate the air conditioning compressor. During cold
weather the engine coolant is used to cool the auxiliary engine and
is circulated through a heat exchanger for warming of the truck
interior. Full capacity of the alternator is allowed, accommodating
the higher amp draws typical of cold weather diesel operation.
Inventors: |
Kennedy, Gino; (North Fort
Myers, FL) |
Correspondence
Address: |
MCHALE & SLAVIN, P.A.
2855 PGA BLVD
PALM BEACH GARDENS
FL
33410
US
|
Family ID: |
46205465 |
Appl. No.: |
11/051429 |
Filed: |
February 3, 2005 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
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11051429 |
Feb 3, 2005 |
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10060091 |
Jan 29, 2002 |
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Current U.S.
Class: |
165/167 ;
165/202 |
Current CPC
Class: |
B61D 27/00 20130101;
B60H 1/00421 20130101 |
Class at
Publication: |
165/167 ;
165/202 |
International
Class: |
F28F 003/08 |
Claims
What I claim is:
1. An auxiliary power system for use in trucks comprising: an
auxiliary engine for selectively providing power to an electrical
generation system and an air conditioning system, said auxiliary
engine being sized so that it is incapable of simultaneous
operation of said air conditioning system and said electrical
generation system to their respective full capacities; a control
relay/regulator for reducing electrical power supplied by said
electrical generation system during simultaneous operation of said
air conditioning system, whereby power supplied by said auxiliary
engine is maximized.
2. The auxiliary power system according to claim 1 wherein said
auxiliary power system includes a heating system.
3. The auxiliary power system according to claim 2 wherein said
heating system includes a water cooled auxiliary engine, a water
pump and a remotely mounted heat exchanger, wherein said heat
exchanger is mounted within a truck cabin area to selectively
provide heat thereto.
4. The auxiliary power system according to claim 3 wherein said
water pump is mechanically driven by said auxiliary engine.
5. The auxiliary power system according to claim 3 wherein said
water pump is electrically driven, wherein said electrically driven
water pump may be selectively operated.
6. The auxiliary power system according to claim 1 wherein said
electrical generation system includes an alternator, wherein said
alternator is operably coupled to said auxiliary engine for
rotation thereof.
7. The auxiliary power system according to claim 6 wherein said
alternator is capable of producing about 120 amperes.
8. The auxiliary power system according to claim 3 wherein said
electrical generation system includes a generator, wherein said
generator is operably coupled to said auxiliary engine for rotation
thereof.
9. The auxiliary power system according to claim 6 wherein said
generator is capable of producing about 120 amperes.
10. The auxiliary power system according to claim 1 wherein said
control relay/regulator is externally mounted with respect to said
alternator.
11. The auxiliary power system according to claim 1 wherein said
control relay/regulator is constructed and arranged to reduce
electrical production of said electrical generation system by about
one half during operation of said air conditioning system.
12. The auxiliary power system according to claim 11 wherein said
control relay/regulator is constructed and arranged to reduce
electrical production of said electrical generation system from
about 120 amperes to about 60 amperes during operation of said air
conditioning system.
13. The auxiliary power system according to claim 10 wherein said
regulator is a microprocessor controlled voltage regulator equipped
with a half power temperature control circuit.
14. The auxiliary power system according to claim 13 wherein said
regulator is a BALMAR model no. MC-612.
15. The auxiliary power system according to claim 13 wherein said
relay is connected between a positive terminal and a negative
terminal provided with said temperature control circuit of said
regulator, whereby closing said relay causes said regulator to
reduce a field current within said alternator thereby reducing
output of said alternator.
16. The auxiliary power system according to claim 1 wherein said
air conditioning system includes a compressor operably connected to
said auxiliary engine for selective rotational operation.
17. The auxiliary power system according to claim 16 wherein said
compressor includes a magnetic clutch for selective operation of
said compressor.
18. The auxiliary power system according to claim 1 wherein said
air conditioner compressor produces about 12,000 BTU and said
auxiliary engine produces about four horsepower.
19. The auxiliary power system according to claim 18 wherein said
engine is a four HP KUBOTA EL 300 AR.
20. The auxiliary power system according to claim 1 wherein said
air conditioner compressor produces about 16,000 BTU and said
auxiliary engine produces about seven horsepower.
21. The auxiliary power unit according to claim 20 wherein said
engine is a seven HP KUBOTA EA 300 NB.
22. The auxiliary power system according to claim 16 wherein said
truck includes an air conditioning system, wherein said auxiliary
air conditioning system is connected to utilize at least a portion
of said truck's air conditioning system.
23. The auxiliary power system according to claim 22 wherein said
truck air conditioning system includes an accumulator, an expansion
valve, an evaporator and a condenser, wherein said auxiliary air
conditioning system utilizes said truck accumulator, expansion
valve, evaporator and condenser.
24. The auxiliary power system according to claim 1 including an
electrical inverter, wherein said electrical inverter is
constructed and arranged to provide alternating electrical power
for operation of truck accessories.
Description
RELATED APPLICATIONS
[0001] This application is a continuation-in-part of applicant's
co-pending U.S. application Ser. No. 10/060,091 filed Jan. 29,
2002, the contents of which are hereby incorporated by
reference.
FIELD OF THE INVENTION
[0002] This invention is related to auxiliary power systems, in
particular, to an auxiliary power system having a load shedding
voltage regulator which prioritizes air conditioning by reducing
electrical power generation to minimize auxiliary engine size
requirements, thus reducing space and weight requirements for the
auxiliary power system.
BACKGROUND OF THE INVENTION
[0003] Total fossil fuel waste, and the associated economic waste,
within the trucking industry is staggering. It is estimated that
six out of every fourteen hours of truck operation are spent
idling. Federal and State laws alike limit the number of hours that
each truck driver can legally drive a truck in a twenty-four hour
period. During the remainder of the time the driver must rest for
the next available driving period. Rest periods are often spent in
rest areas, truck stops or along the side of an interstate. Trucks
or tractors are often supplied with a "sleeper" for the driver to
spend his or her rest time. Often the sleeper includes modern
amenities such as a television, VCR, DVD, satellite dish,
refrigerator, air conditioner, coffee maker, even a microwave oven.
While such items may run on direct current provided by an engine
mounted alternator, or even alternating current by use of an
inverter, the truck engine must remain running to prevent the
discharge of the batteries used for starting of the diesel engine.
During idle a typical diesel truck engine will burn about one
gallon of diesel fuel per hour. In addition to the cost of the
diesel fuel, normal maintenance costs to the truck engine and its
associated systems are increased.
[0004] In order to reduce fuel and maintenance costs, trucks often
utilize an auxiliary generator to provide electrical power for
systems within the truck when the truck's engine is not running.
The Applicant is a well known assembler of diesel engine/generators
packages and has been awarded patents for various arrangements.
U.S. Pat. Nos. 5,765,805, 6,047,942, 6,119,638, 6,677,684,
6,756,693 and 6,812,582 granted to the Applicant disclose
combination engine/generator sets that are lightweight and of novel
space saving configurations, the contents of which are incorporated
herein by reference.
[0005] The prior art also discloses numerous systems by which air
conditioning and heating can be provided to the interior of a truck
while the main engine is not running. For example, U.S. Pat. No.
4,756,359 discloses an auxiliary power system that includes an
auxiliary engine, electrical alternator, water pump, air
conditioning compressor and heat exchanger. The heat exchanger is
used to receive hot exhaust gases from the auxiliary engine for
purposes of heating coolant routed through the truck's engine.
[0006] U.S. Pat. No. 4,762,170 discloses an auxiliary power system
for trucks or other heavy duty vehicles. The system includes an
auxiliary engine sized to simultaneously power an air conditioner
compressor and a generator. The cooling system of the auxiliary
engine is connected to the cooling system of the truck's engine to
keep the truck engine warm in cold weather.
[0007] U.S. Pat. No. 5,528,901 discloses an auxiliary power system
which includes an auxiliary engine sized to power an air
compressor, a water pump, an A/C compressor and an oil pump. The
system replaces the original bank of batteries supplied with the
truck and replaces the OEM electric starter with a pneumatic
starter.
[0008] Problems generally associated with the use of these prior
art devices relate to size, weight, and placement of the systems.
The size of an auxiliary generator is critical for vehicular use.
If the overall dimensions are too large, there will be insufficient
areas on a truck for which to place the system. Other problems
result from complexity of installation and the costs associated
therewith. Still other problems result from sharing coolant
systems. Small engines rarely generate enough heat to maintain
temperature within a large cooling system such as those supplied
with a large truck. As a result of the constant cold cylinder
temperature the small engine runs inefficiently. Some systems
increase the size of the auxiliary engine or place false loads on
the auxiliary engines to increase heat transferred to the large
engine's cooling system to maintain higher overall temperatures.
However, the false loads and oversized engines decrease the overall
efficiency of these systems. Other problems and expense are
incurred with the use of water-to-water or water-to-oil heat
exchangers. The heat exchangers are expensive, difficult to
install, and require each body of fluid to be equipped with an
independent pump for fluid circulation.
[0009] It is also known to vary the output of a generator for
specific applications. For example, U.S. Pat. No. 4,099,067
discloses a control for diesel-electric motor-generator sets. The
device allows temporary overloads to be accommodated without engine
lugging by reducing line voltage if an attempt is made to draw more
than a preset maximum normal wattage. The line voltage reduction is
accomplished by increasing the impedance of the voltage regulator
input circuit when a signal generally proportional to line voltage
and load current exceeds a preset reference signal to which it is
compared.
[0010] U.S. Pat. No. 5,512,813 discloses an A/C generator output
controlling apparatus. The control device determines the field
current to be supplied to a field coil on the basis of a voltage
deviation between a battery charging voltage and a battery target
voltage.
[0011] U.S. Pat. No. 5,739,677 discloses a vehicle power generating
system. The system includes a controller which varies the supply of
leading phase current supplied to the power generator. The system
is particularly suited for low RPM, high power generation.
[0012] U.S. Pat. No. 5,726,559 discloses a synchronous electric
power generating apparatus and magnetization control method.
Advance-phase currents are supplied to stator windings via
semiconductor switching devices by controlling the semiconductor
switching devices during power generation. The device and method
are particularly suited to control rotor temperature and reduce
magnetic flux in an alternating current power generator.
[0013] U.S. Pat. No. 5,726,557 discloses a vehicular power system.
The device includes a rotating alternating current machine having
polyphase armature coils and a full wave rectifier for rectifying
the generated voltage by a plurality of SiC-MOSFETs, to give a
rectified output to the battery unit. The device also includes a
control device for selectively turning on the plurality of
SiC-MOSFETs to raise the generated voltage by short-circuiting and
open-circuiting the armature coils on the basis of the phases of
voltage generated by the rotating alternating current machine.
[0014] These prior art devices are generally geared to maximizing
the output of a power generating device without overloading or
overcharging the electrical system of the vehicle. The engines
utilized to drive these devices are generally of sufficient size to
drive the generator at full capacity for extended periods. None of
the prior art devices disclose or teach a system which is
constructed to utilize a minimally sized engine to prioritize and
drive alternative loads.
[0015] Thus, what is needed is an auxiliary power system that is
lightweight, consumes a small space, and may be used to
alternatively provide heating, electrical power or air conditioning
to the interior of a truck. The auxiliary power system should be
capable of shedding low priority demands for maximizing power
supplied by the auxiliary engine.
SUMMARY OF THE INVENTION
[0016] The instant invention system includes a small diesel engine
coupled to an air conditioner compressor, a generator or alternator
and a combination control relay/regulator for maximizing the loads
placed on the auxiliary engine. The truck operator is provided with
controls for selective operation of the auxiliary power system's
various features which may be operated while the truck's main
engine is running or stopped.
[0017] In the preferred embodiment the auxiliary engine is sized so
that it is not capable of simultaneous operation of all the
auxiliary systems to their maximum capacity. In a most preferred
embodiment the auxiliary engine is rated from about three HP to
about eight HP. Such engines are currently available from
manufacturers such as KUBOTA, and may have a horizontally or about
vertically disposed cylinder.
[0018] One embodiment of the auxiliary power system includes a
heating system. The heating system includes a water pump which may
be electric or mechanically driven by the auxiliary engine.
Operator controls permit the water pump to circulate water through
the auxiliary engine to a sleeper heat exchanger, radiator or both.
The heat exchanger may be remotely mounted within the interior of
the truck to provide heat within the truck interior, and may
further include an electric fan for forcing air across the heat
exchanger to provide additional heat. The fan may be operated via
the driver's controls to regulate the amount of air passed across
the heat exchanger to provide warmth to the truck's interior. While
the air conditioning compressor is turned off, via the driver's
controls, the full capacity of the alternator or generator is
available for the higher amp draws typical of cold weather where
diesel engines are harder to start and more electrical accessories
are in use.
[0019] During hot weather operation the driver may utilize the
controls to start the auxiliary engine. The auxiliary engine may
then be utilized to operate an air conditioner compressor and
related air conditioner system components, wherein the truck
interior is kept cool. During this mode the auxiliary engine is
also utilized to operate the alternator or generator to replenish
power drawn from the truck batteries. In order for the auxiliary
engine to provide power for both accessories, a control
relay/regulator is utilized to switch the input field of the
alternator, thereby reducing alternator output to maximize the
power output of the auxiliary engine. Should the truck accessories
draw more electrical power than the alternator or generator supply
during such a peak demand, the truck batteries operate as a reserve
power source. When the air conditioning compressor cycles off, the
control relay/regulator causes the alternator or generator to
increase electrical output to replenish the truck batteries and
supply electrical power to other accessories. In this manner the
power output provided by the auxiliary engine may be more fully
utilized than in prior art power systems.
[0020] Thus, an objective of the instant invention is to teach an
auxiliary power system for trucks that utilizes a minimally sized
engine to selectively operate air conditioning, heating and power
generating systems.
[0021] Another objective of the instant invention is to teach a
minimally sized auxiliary power system for trucks capable of
selectively providing air conditioning, heating, and electrical
power to the interior area of the truck.
[0022] Still another objective of the instant invention is to teach
an auxiliary power system having a control relay/regulator
constructed and arranged to maximize utilization of the power
supplied by the auxiliary engine.
[0023] Yet another objective of the instant invention is to teach
an auxiliary power system which includes a control relay/regulator
constructed and arranged to maximize utilization of power supplied
by an auxiliary engine by controlled reduction of electrical power
production for simultaneous air conditioner compressor
operation.
[0024] Still yet another objective of the instant invention is to
teach an auxiliary power system which utilizes existing truck
batteries as a power exchanger for peak accessory loads.
[0025] Another objective of the invention is to teach an auxiliary
power system for trucks that captures heat from the engine coolant
for warming of the truck interior.
[0026] Yet another objective of the invention is to teach the use
of an auxiliary power system that is inexpensive, small in size and
lightweight.
[0027] Other objectives and advantages of this invention will
become apparent from the following description taken in conjunction
with the accompanying drawings wherein are set forth, by way of
illustration and example, certain embodiments of this
invention.
BRIEF DESCRIPTION OF THE DRAWINGS
[0028] FIG. 1 is a diagrammatic representation of the instant
invention auxiliary power system;
[0029] FIG. 2 is a diagrammatic representation of the instant
invention auxiliary power system used in conjunction with an under
bunk heating and air conditioning system; and
[0030] FIG. 3 is a diagrammatic representation of the instant
invention auxiliary power system in a heat providing mode.
DETAILED DESCRIPTION
[0031] Now referring to FIG. 1, a diagrammatic representation of
one embodiment of the instant invention auxiliary power system 100
is illustrated. The auxiliary power system generally includes an
auxiliary engine 10 for selectively providing power to an
electrical generation system 102, an air conditioning system 104,
and a heating system 106. In the preferred embodiment the auxiliary
engine is sized so that it is not capable of simultaneous operation
of the air conditioning system and the electrical generation system
to their respective full capacities. The auxiliary power system
includes a unique control relay/regulator combination 24, 28 for
reducing electrical power produced by the electrical generation
system 102 during simultaneous operation of the air conditioning
system 104. This construction and arrangement permits the size and
weight of the auxiliary power system to be substantially smaller
than the power systems of the prior art. The arrangement also
permits the auxiliary power system to utilize a small single
cylinder diesel engine which requires less frequent oil change
intervals than those required by the larger engines of the prior
art.
[0032] Referring to FIGS. 1-3, the auxiliary engine 10 is coupled
to a refrigerant compressor, e.g. air conditioner compressor 12 and
an alternator 22. The air conditioner compressor is generally an
automotive style compressor which includes a magnetic clutch, well
known in the art, suitable for compressing any of the various
refrigerants, also well known in the art. In one embodiment the
compressor 12 is constructed and arranged to cooperate with the
accumulator (not shown), expansion valve (not shown), evaporator
16, condenser 14 and air conditioner controls 18 supplied with a
truck.
[0033] In the preferred embodiment, a high output automotive style
alternator 22 is suitably coupled to the auxiliary engine 10 for
rotation thereof. The alternator 22 may be based on 12 volts, 24
volts or other voltage dependant upon the trucks electrical system.
In an alternative embodiment, a generator may be utilized in place
of the alternator 22 to provide electrical current to various air
conditioner support components and other accessories as well as
batteries. The power produced by the alternator is available for
operating accessories such as an alternating current inverter 20
connected to standard receptacles 30, allowing the operation of
household appliances such as razors, coffee makers, microwave
ovens, alarm clocks, VCR's and so forth. Further 12 volt components
and accessories such as parking lights, interior lights,
television, CB radio, sound system, refrigerator, and like devices,
not shown, are all commonly used and require power for operation.
Should the power requirements be exceeded, due to peak draw devices
such as a microwave oven or coffee maker, the existing truck
batteries 38 will produce the necessary power by operating as a
power sink.
[0034] In a most preferred embodiment, a single cylinder Kubota EL
300 AR engine capable of producing about four HP is coupled to a
12,000 BTU air conditioner compressor and a high output alternator
22 of about 120 amps on a 12 volt system. The size of the Kabota
engine and the horizontal orientation of the cylinder allow the
instant invention auxiliary power system 100 to be packaged into a
small and lightweight add on device for the trucking industry. In
an alternative embodiment, a Kubota EA 300 NB engine capable of
producing about seven HP may be coupled to, or rotate an air
conditioner compressor at a higher rate, so as to produce about
16,000 BTUs of air conditioning as well as simultaneously operate
the high output alternator at reduced output. It is also
contemplated that other engines having vertically oriented
cylinders and/or a larger power output could also be utilized
without departing from the scope of the invention.
[0035] Load management control is provided by the control
relay/voltage regulator combination 24, 28. The preferred
embodiment utilizes an externally mounted microprocessor controlled
voltage regulator 28. The voltage regulator 28 is equipped with a
reduced power setting, which is typically utilized to control
alternator temperature in a marine environment. Such regulators are
available from BALMAR Corp. of Arlington Va., model no. MC-612. The
instant invention connects a relay 24 between the positive and
negative terminals of the temperature circuit provided with the
regulator 28. When the relay switch 24 is activated, the regulator
28 reduces the field current at the alternator 22. Within the
instant invention the control relay 24 is activated during
operation of the air conditioning compressor 12. Activation of the
relay reduces the output of the alternator by approximately 50% to
reduce the load on the auxiliary engine 10, thereby allowing a
small engine to operate both systems simultaneously. As the air
conditioner clutch disengages, control relay 24 also opens to allow
higher electrical production by the alternator 22.
[0036] It should also be noted that other regulators or regulation
methods, well known in the art, that are suitable for controlled
reduction of alternator or generator electrical production in
response to air conditioner compressor engagement may alternatively
be utilized without departing from the scope of the instant
invention.
[0037] Referring to FIG. 2, an alternative embodiment of the
auxiliary power system is illustrated. In this embodiment the air
conditioner compressor cooperates with an under bunk combination
air conditioner and heater unit 32. In this embodiment the
accumulator, expansion valve, evaporator, condenser and air
conditioner controls are contained within the under bunk unit.
Under bunk heat and air conditioner units for trucks are well known
in the art.
[0038] Referring to FIG. 3, operation of heat system 106 is
illustrated. During operation of the heat system, water used to
cool the auxiliary engine 10 is circulated through a remotely
mounted water to air heat exchanger 52 by opening of a water valve
54. The engine coolant is fluidly coupled 42 to the heat exchanger
located in the evaporator/heater assembly 16 with an outlet 44
coupled to the radiator assembly 14 which is then circulated back
to the engine 10 by the water pump 40. The evaporator/heater fan 17
may be turned on and used to draw air through or across the heat
exchanger for increased warming of the truck interior. The electric
radiator/condenser fan 26 cycles as required by the temperature
switch 27 to reduce auxiliary engine temperatures. It should be
noted that by operating the auxiliary engine at its' optimum RPM's
and operating the alternator at approximately 80% of full
electrical load draw, the engine is operated at its most fuel
efficient level and provides a fast and reliable heat source for
the sleeper area of the truck. The additional amperage draw may be
used to power the parking lights, television, CB radio,
refrigerator, AC inverter, interior lights and so forth necessary
in cold weather operation. It has been found that a block heater
provides a unique false load to the engine causing the engine to
operate at peak efficiency. The block heater causing the engine
temperature to reach its operating condition quickly while the
additional load placed on the engine results quicker temperature
increase. Further, the use of a water cooled alternator provides a
means to recover heat for delivery to the cab.
[0039] Referring to FIGS. 1-3, general operation of the auxiliary
power system will be described. Upon start up of the auxiliary
engine 10, the oil pressure within the auxiliary engine is checked
via oil pressure switch 20. If sufficient oil pressure is detected
voltage is supplied to the auxiliary water pump 40 and relay 34.
The auxiliary electrical system becomes active and current from the
battery is allowed to flow through line 46 of regulator 28, and the
alternator 22 begins to deliver electrical power to the battery 38.
For operation of the auxiliary air conditioning system 102, relay
34 is closed to allow electrical current to flow to the air
conditioning control 18. The air conditioner controls are
manipulated by the operator, e.g. driver, to control the auxiliary
heating system 106 and the auxiliary air conditioning. Should the
operator desire air conditioning the air conditioning controls 18
are manipulated to cause the compressor 12 to engage the auxiliary
engine 10. Simultaneously, the control relay 24 closes to cause the
voltage regulator 28 to reduce the output of the alternator 22. The
air conditioner control also selectively operates the
evaporator/heater fan 17 and the condenser fan 26 as needed. A
compressor clutch (not shown) remains engaged as long as the air
conditioner pressure switch 48 is closed, causing the compressor to
cycle on and off as required to achieve the air conditioning
control setting.
[0040] Should the operator desire to operate the auxiliary heat
system, the air conditioner controls are manipulated to open the
water valve 54 and start the water pump 40. Water is then forced to
flow through the heat exchanger 52 and optionally through the
radiator 14 before returning to the auxiliary engine 10. For
increased heat, the fan 17 may be operated to increase air flow
over the heat exchanger. In this mode the control relay 24
generally remains open, allowing the alternator to produce
electricity to its full potential.
[0041] For purposes of simplification this application has been
directed to trucks although it would be obvious to one of ordinary
skill in the art to recognize that the teachings of this patent and
the associated claims may be directed to buses, boats, ambulances
and so forth. Further, alternator changes to address higher voltage
systems may be substituted throughout this specification and
considered an obvious variation within the scope of the patent. It
is to be understood that while I have illustrated and described
certain forms of my invention, it is not to be limited to the
specific forms or arrangement of parts herein described and shown.
It will be apparent to those skilled in the art that various
changes may be made without departing from the scope of the
invention and the invention is not to be considered limited to what
is shown in the drawings and described in the specification.
* * * * *