Note : Les descriptions sont présentées dans la langue officielle dans laquelle elles ont été soumises.
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LOAD MANAGEMENT AUXILIARY POWER SYSTEM
2 RET~ATED APPLICATIONS
3 This application is a continuat.ian-in--part of applicant's
4 co~pend~.tYy U.S. App~.ication No. 10/060,091 filed Janurary 29,
2002, the contents of which are hereby ~.ncorporated by
6 reference.
7
8 FIELD OF TIDE T.N~TBrITTON
9 This invention is related to auxiliary power systems, in
particular, to an auxiliary power system having a load shedding
12 voltage regulator Which prioritizes air conditioning by
12 reducing electrical power generation to mib.imize auxiliary
13 engine size requirements, thus reducing space and weight
14 requirements for the auxiliary power system.
16 BACKGROUND OF THE INVENTION
17 Total fossil fuel waste, and the associated economic
2$ waste, within the trucking industry is staggering. It is
29 estimated that six out of every fourteen hours of truck
operation are spent idling. Federal and State laws alike limit
2~, the number of hours that each truck driver can legallar drive a
22 truck in a twenty-four hour period. During the xemainder of
23 the time the driver must rest for the next available driving
24 period. Rest periods are often spent in rest areas, truck
stops or along the side of an interstate. Trucks or tractors
r
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1 are often supplied with a "sleeper" for the driver to spend his
2 or her rest time_ Often the sleeper_ includes modern amenities
3 such as a television, vCR, bvD, satel~.ite dish, refrigerator,
4 air conditioner, coffee maker, even a microwave oven. While
such items may run on direct current prov~.ded by an engine
6 mounted alternator, or even alternating current by use of an
7 inverter, the truck engine must rema~.n running to prevent the
8 discharge of the batteries used for starting of the diesel
9 engine. During idle a typ~.cal diesel truck engine will burn
1o about one gallon of diesel fuel per hour. Tn addition to the
1~. cost of the diesel fuel, normal maix~tenance costs to the truck
12 engine axed its associated systems axe increased.
13 Tn order to reduce fuel and maintenance costs, txu.cks
Z4 oFten utilize an auxiliary generator to provide electrical
z5 power for systems with~.n the truck when the truck's engine is
1G not xwnning. The Applicant is a well known assembler of diesel
17 engine/gerierators packages and has been awarded patents for
18 variov.s arrangements_ U_S. Patent Nvs. 5,765,805, 6,047,942,
29 6,219,638, &,677,68, 6,756,693 and 6,812,582 granted to the
2o Applicant disclose combination engine/generator sets that are
2I -lightweight and of novel space saving configurations, the
22 contents of which are incorporated herein by reference.
23 The prior art also discloses numerous systems by which air
24 conditioning and heating can be provided to the interior of a
25 truck while the main engine is not running. For example, U.S.
z6 Patent No. 4,756,359 discloses an auxia.iary power system that
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1 includes an auxila.ary engine, electrical alternator, water
2 pump, air conditioning Compressor and heat exchanger. The heat
3 exchanger is used to receive hot exhaust gases from the
auxiliary engine for purposes of heating coolant routed through
the truck~a engine.
6 'U.S. Patent No_ 4, 762, 170 discloses an auxiliary po~.ter
7 system for trucks or other heavy duty vehicles. The system
8 includes an auxiliary engine sized to Nimultaneously power an
9 air conditioner compressor and a generator. The cooling system
ZO of the auxiliary engine is connected to the cooling system of
1s the truck's engine to keep the truck engine warm ix~ cold
12 weather.
13 U_5. Patent No. 5,528,901 discloses an auxiliary power
14 system which includes an auxiliary engine sized to power an air
z5 compressor, a v'ater pump, an A/C compressor and an oil pump_
16 The system replaces the original. bank of batteries supplied
7.7 with the truck and replaces the OEM electric starter With a
18 pneumatic starter.
19 Problems generally associated with the use of these prior
zo art devices relate to size, weight, and placement of the
21 systems. The size of an auxiliary generator is critical for
22 vehicular use. If the overall dimensions are too large, there
23 will be insufficient areas on a truck for which Co place the
24 system. Other problems result from complexity of installation.
25 and the costs associated therewith. Still other problems
26 result from sharing coolant systems. Small engirxes rarely
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1 generate enough heat to maintain temperature within a large
2 cooling system such as those supplied with a large truck. As
3 a result of the constant cold cylinder tenzperature the small
4 engine runs inefficiently. Some systems increase the size of
the auxiliar~r engine or p7.ace false loads on the auxiliary
6 engines to increase heat transferred tv the large engine's
cooling system to maintain higher overall temperatures.
s However, the false loads and oversiaed engizxes decrease the
9 overall efficiency of these systems. Other problems and
l0 expense are incurred with the use of water-to-water or water-
~l to--oil heat exchangers. The heat exchangers axe expensive,
12 difficult to install, and require each body of fluid to be
13 equipped with an independent pump for fluid circulation.
14 It is also known to vary the output of a generator for
specific applications. For example, U.S. Patent No. 4,099,067
s6 discloses a control for diesel-electric motor-generator sets.
17 The device allows temporary overloads to be accommodated
18 without engine lugging by reducing line voltage if an attempt
19 is made to draw more than a preset maximum normal Wattage. The
line voltage reduction is accomplished by increasing the
21 vmpedaance of the voltage regulator input circuit when a signal
22 genera7.ly proportional to line voltage and load current exceeds
23 a preset reference signal to wha.ch it is compared.
24 U.S. Patent No. 5,512,813 discloses an A/C generator
output controlling apparatus. The control device determines
26 the field current to be supplied to a field~coil on the basis
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1 of a voltage deviation between a battery charging vol-tage and
2 a battery target voltage.
3 U.S. Patent No. 5,739,6~~ discloses a vehicle power
4 generating system. The system includes a controller wlxich
varies the supply of leading phase current supplied to the
6 power generator. The system is particularly suited fox low
7 RPM, high power generation_
8 U.S. Patent No. 5,726,559 discloses a synchronous electric
9 pov~r generating apparatus and magnetisation control method.
Advance-phase currents are supplied to stator wir~,dings via
11 semiconductor switching devices by controlling the
12 semiconductor switching devices during power generation. The
13 devzGe and method axe particularly su~.ted to control rotox
14 temperature and reduce magnetic flux in an alternating current
power generator.
16 U.S. patent No. 5,726,557 discloses a vehicular power
17 system. The device includes a rotating alternating current
1s machine having polyphase armature coils and a full wave
i9 rectifier for rectifying the generated voltage by a plurality
of SiC-MOSF~Ts, to give a rectified output to the battery unit.
21 ~'he device also .includes a control device for selectively
22 turning on the plurality of SiC-MOSFETs to raise the generated
23 voltage by short-circuiting and open-circuiting the armature
24 coils on the basis of the phases of voltage generated by the
x-otating alternating current machine.
26 These prior art devices are generally geared to maximizing
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:1 the output of a power generating device without overloading ox
2 overcharging the eler_trical system of the vehicle. The engizies
3 utilized to drive these devices are generally of sufficient
4 size to drive the generator at full capacity for extended
periods. None of the prior art devices disclose or teach a
6 system which is Constructed to utilize a minimally sized engine
7 to prioritize anal drive alternative loads.
8 Thus, what is xieeded is an auxiliary power system that is
9 lightweight, consv.mes a small space, and may be used to
Zo alternatively provide heating, eleetr~.caZ power or air
11 conditioning to the interior of a truck. The auxiliary power
12 system should be capable of shedding low priority demands for
~.3 maximiza,ng power supplied by the auxiliary engine.
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1 ST~MA.R7f OF THE INVENTION
2 The instant ~.7rsvention system includes a small diesel
3 engine coupled to an air condit~.oner compressor, a generator or
4 alternator and a combination control xelayJregulator for
S maxzmiaing the loads placed on the auxiliary engine. The truck
6 operator is provided with cozitrols ~or selective operation of
7 the auxiliary power system's various features which mar be
8 operated while the truck's main engine is ruiuzing or stopped.
In the preferred embodiment the auxiliary engine is sized
so that it is not capable of simultaneous operation of all the
I1 auxiliary systems to their max~,mum capacity. In a most
12 preferred embodiment the aux~.liary engine is rated from about
13 three SIP to about eight HP. Such engines are currently
14 available from manufacturers such as KUB~TA, and may have a
horizontally or about vertically disposed cylinder_
16 One embodiment of the auxiliary power system includes a
17 heating system. The heating system includes a water pump which
18 may be electric or mechanically driven by the auxiliary engine .
operator controls permit the water pump to circu~.ate water
zo through the auxiliary engine to a sleeper heat exchanger,
21 radiator or both_ The heat exchanger may toe remotely mounted
22 within the interior of the truck to provide heat Within the
23 truck interior, and may further include an electric fan fox
24 forcing air across the heat exchanger to provide additional
2S heat. The fan may be operated via the driver's controls to
z6 regulate,the amount o;~ air passed across the heat exchanger to
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7. provide warmth to the truck's intet~ior. While the air
2 coz~ditioning compressor is turned off, via the dr~.ver~ s
3 controls, the full capacity of the alternator or generator is
4 available for the higher amp draws txpical of cold weather
where diesel engines are harder to start and more electrical
6 accessoxies are ire use . '
7 During hot weather operation the dri~rer may utilize the
8 controls to start the auxiliaxy engine. The auxiliary engine
9 may then be utilized to operate an air conditioner compressor
and related air conditioner system components, whexein the
1z truck interior is kept cool. T.~uring this mode the auxiliary
1.2 engine is also utilized to operate the alternator or generator
13 to replenish power drawn from the truck batteries. 2n order
14 for the auxiliary engine to provide power for both accessories,
z5 a control relay/regulator is utilized to switch the input field
16 .of the alternator, thereby reducing alternator output to
17 maximize the power output of the auxiliary engine. Should the
z8 truck accessories draw more electrical power than the
i9 alternator or generator supply during such a peak demand, the
truck batteries operate as a reserve power source. When the
21 air conditioning compressvx cycles off, the control
22 relay/regulator causes the alternator or generator to increase
23 electrical output to replenish the truck batteries and supply
24 electrical power to other accessories. in this manner the
power output provided lay the auxiliary engine may be more fully
26 utilized.than in prior art power systems_
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1 Thus, ari objective of the instazlt invention is to teach an
2 auxil~.ary power system for trucks that utilizes a minimally
3 sized engine to selectively operate air conditioning, heating
4 and power generating systems.
Another objective of the instant invention is to teach a
6 minimally sized aux~.li.ary power system for trucks capable of
7 selectively providing air conditioning, heating, and electrical
power to the interior area of the truck.
9 Still another objective of the instant invention is to
teach dzx auxiliary power system having a control
iz relay/regulator constructed and arranged to maximize
1z utilization of the power supplied by the auxiliary engine.
z3 Yet another obj active of the instant invention is to teach
14 an auxiliary power system which includes a control
~.5 relay/regulator constructed and arranged to maximize
16 utilization of power supplied by an auxiliary engine by
1~ controlled reduction of electrical power production fox
18 simultaneous air conditioner compressor operation.
19 Still yet another objective of the instant invent~,on is to
teach an auxiliary power system which utilizes existing truck
21 batteries as a power exchanger fox peak accessory leads.
22 Another objective of the invention is to teach an
23 auxi7.iary power system for trucks that captures heat ~rom the
24 engine coolant far warming of the truck interior.
Yet another objective of the invention is to teach the use
26 of an auxiliary power system that is inexpensirre, small in size
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1 and lightweight.
2 other objectives and advantages of this ~.~nvention will
3 become apparent fxom the following description taken in
conjunction with the accompanying drawings wherein are set
forth, by way of illustration and example, certain embodiments
6 of this invention.
7
8 BRIEF DESCRTPTION OF T~3E DRp,WINGS
9 Figure 1 is a. diagrammatic representation of the instant
invention auxiliary power system;
11 Figure 2 is a diagrammatic representation of the instant
12 invention auxiliar~r power system used in conjunction with an
13 under bunk heat~:ng and air condition~.ng system; and
1g Figure 3 is a diagrammatic representation of the instant
1s snventivn auxi~.iary power system in a heat providing mode.
16
17
18
19
24
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1 DETAILEi7 DESCRIPTION
2 Now referring to Fig. 1, a diagrammatic representation.of
3 one embodiment of the instant invention auxiliary power system
4 10o is illustrated. The auxiliary power system generally
S includes an auxiliary engine 20 for selectively providing power
6 to an electrical generation system 1'02, an air conditioning
7 system Z04, and a heating system l05_ 2n the preferred
8 embodiment the auxiliary engine is sized so that it is not
capable of simultaneous operation of the air condit~.onir~g
to system and the electrical generation system to their respective
1~ full capacities. The auxiliary powez system includes a unique
1z control xelay/regulator combination 24, 28 for reducing
~.3 eJ.ectrical power produced by the electrical generation system
1~ 102 during simultaneous operation of the air conditioning
15 system 10~. This construction and arrangement per~eits the size
16 and weight of the auxiliary power system to be substantially
1'~ smaller than the power systems of the prior art. The
18 arrangement also permits tb.e auxiliary power system to utilize
19 a small single cylinder d~.esel erzgine which requires less
20 frec~ueat oil change intervals than those required by the larger
21 engines of the prior art.
22 Referring to Figs. 1-3, the auxiliary engine to is coupled
23 to a refrigerant compres sor, a . g. air eonditivner compressor 1z
2~ and an alternator 22. The air conditioner compressor is
25 generally an automotive style comQressor which includes a
26 magnetic.elutch, well known. xn the art, suitable for
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1 compressing ally of the various refrigerants, also well known iaz
2 the art. In one embodiment the compressor 12 is constructed
3 and arranged to cooperate with the accumulator (not shown),
4 expansion valve (not shown), evaporator 16, condenser 14 and
air conditioner coi~trols 18 supplied with a truck.
6 In the preferred embodiment, a high output automotive
7 style alternator 22 is suitably coupled to the auxiliary engine
8 1o for rotation thereof. The alternator 22 may be based on 12
9 volts, 24 volts or other voltage dependax~t upon the trucks
l0 electrical system. In an alternative embodiment, a generator
~.1 may be utilized in place of the alternator 22 to provide
12 electrical current to various air conditioner support
s3 components and other accessories as well as batteries. The
14 power produced by the alternator is available for operating
1S accessories such as an alternating current inverter 2o
16 connected to standard receptacles 30, a~.lowing the operation of
1~ household appliarsees such as raaors, coffee makers, microwave
18 ovens, alarm clocks, vCR~s and so forth. Further 12 volt
3:9 components and accessor~,es such as parking lights, interior
20 lights, television, CB radio, sound system, refrigerator, and
21 Zike devices, not shown, are all commonly used and require
22 power for operation. Should the power requirements be
23 exceeded, due to peak draw devices such as a microwave oven or
24 coffee maker, the existing truck batteries 38 will. produce the
25 necessary power by operat~.ng as a power sink.
26 in a'most preferred embodiment, a single cylinder iCubota
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1 EL 300 AR engine capab~,e of producing about four HP is coupled
2 to a 12,000 BTU air conditioner compressor and a high output
3 alternator 22 of about x.20 amps on a 12 volt system. The size
4 of the Kabota engine and the horizontal orientation of the
S cylinder allow the instant invention auxiliary power system 7.00
6 to be packaged into a small and light'vaeight add on device for
7 the trucking industry. Tn an alternative embodiment, a Kubota
8 EA 30o Ns engine capable of producing about seven HP may be
9 coupled to, or rotate an air conditioner compressor at a higher
20 rate, so as to produce about Z6, 000 BTUs of air conditioning as
hl well as simultaneously operate the high output alternator at
7.2 reduced output. It is also contemplated that other engines
13 having vertically oriented c~rlinders and/or a larger power
3.4 output could also be utilized witb~out departing from the scope
15 of the invention.
16 Zoad management control. is provided by the control
17 relay/voltage regulator combinative 24, 28. The preferred
1s embodiment utilizes an externally mounted microprocessor
19 controlled voltage regulator 28. The voltage regulator 28 is
2o equipped with a reduced power setting, which is typically
2~. uailized to control alternator temperature in a marine
22 environment. Such regulators are availab7.e from BALMAR Corp.
23 of Arlington Virginia, model no. MC-612. The instant invention
24 connects a relay 24 between the positive and negative tex~mirxals
25 of the temperature circuit provi,dsd with the regulator 2s_
25 When the relay switch 24 is activated, the regulator 28 reduces
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the field cux'xent at the alternatoY 22. Within the instant
z invention the control relay 24 ~.s activated during operation of
3 the air conditicaning compressor 12. Activation of the zelay
4 reduces the output of the alternator by approximately So% to
reduce the load on the~auxiliary engine lo, thereby allowing a
6 small, engine to operate both systems~simultaneously. As the
7 air conditioner clutch disengages, control relay 24 also opens
8 to allow higher electxiCal production by the alternator 22.
9 Tt should also be noted that o~:her regulators ox
regulation methods, well known in the art, that are suitable
11 for controlled reduction of alternator or generator electrical
12 production in response to air conditioner compressor engagement
13 may alternatively be utilized without departing from the scope
14 of the instant invention.
Referring to Fig. 2, an alternative embodiment of the
i6 auxiliary power system is illustrated. In this embodi~nnent the
1~ air conditioner compressor cooperates with an under bunk
18 combination air conditioner and heater unit 32. Tn this
19 embodiment the accumulator, expansion valve, evaporator,
condenser and air conditioner contro7.s contained within the
are
21 under bunk unit. Under bunk heat and air conditioner units for
22 trucks are well
known in the art
.
23 Referring to Fig.
~, operation of
heat system 106
is
2~ illustrated. Durixag operation of the heat system, water used
to cool the auxiliary engine 10 ie circulated through a
26 remotely mounted water to air heat exchanger S2 by opening of
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1 a water valve 54_ The engine coolant is tlu~dly coupled X12 to
z the heat exchanger located in the evaporatorjheater assembly 15
3 with an outlet 44 coupled to the radiator asseittbly 14 which is
4 then circuJ.ated back to the engirxe 10 by the water pump 40.
T~.~e evaporator/heater fan 17 may be turned on and used to draw
6 air through or across the heat exchanger for increased warming
7 of the truck interior. The electric radiatoxjcondenser fan 26
cycles as required by the temperature switch 2~ to reduce
9 auxiliary engine temperatures. It should be noted that by
l0 operating the auxiliary engine at its' optimum RPM~s and
11 operating the alternator at approximately 80~ of full
12 electrical load draw, the engine p.s operated at its most fuel
~.3 efficient level and provides a fast and reliable heat source
~4 for the sleeper area of the truck. The additional amperage
draw may be used to power the parking lights, television, c$
16 radio, refrigerator, AC inverter, interior lights and so forth
17 necessary in cold weather operation. It has been found that a
18 block heater provides a unique false load to the engine causing
19 the engine to operate at peak efficiency. The block heater
causing the engina temperature to reach its operat~.ng condition
21 quickly while the additional load placed on the engine results
22 quicker temperature increase. Further, the use of a water
23 cooled alternator provides a means to recover heat fax delivery
2~1 to the cab.
Referring to Figs _ 1-3 , gex~eral operation of the auxiliary
26 Bower system will be~described. Upon start up of the auxiliary
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1 engine 10, the oz~, pressure within the auxiliary engine is
2 checked via oil pressure switch 20. if sufficient oil pressure
3 is detected vo7.tage is supplied to the auxiliary water pump 40
4 and relay 3~. The auxiliary electrical system becomes active
and current from the battery is allowed to flow through line 46
6 of regulator 2s, and the alterxxator 22 begins to deliver
7 electrical power to the battery 38. For. operation of the
8 auxiliary air condition,a.ng system zp2, relay 3.~ is closed to
9 allow electrical curreua.t to f7.ow to the air conditioning
control 1B. The air conditioner controls are manipulated by
1.1 the operator, e.g. driver, to control the auxiliary heating
12 system 1,06 and the auxiliary air conditioning_ Should the
~.3 operator desire air conditioning the air conditionirag controls
14 16 are manipulated to cause the compressor 1z to engage the
auxiliary engine 10. Simultaneously, the control relay z~
16 closes to cause the voltage regulator z8 to reduce the output
17 of the alternator 22. The air conditioner control also
1.s selectively operates the evaporator/heater fan 17 and the
19 condenser fan 26 as needed. A compressar clutch (not shown)
remains engaged as loz~.g as the air conditioner pressure switch
21 48 is closed, causing the compressor to cycle on azxd off as
22 required to achieve the air conditioning control setting.
23 Should the operator desire to operate the auxiliary heat
24 system, the air conditioner controls are manipulated to open
the water valve 54 and start the water pump 40_ Water is then
26 forced to flow through the heat exchanger s2 and optionally
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1 through the radiator 14 betore returning to the aux~.liary
2 engine 10_ ~'or increased heat, the fan 17 may be operated to
3 increase air flow ever the heat exchanger. In this mode the
4 control re~.ay 24 generally remains open, allowing the
S alternator to produce electricity to its full potential_
6 For purposes of simplification this applicat~.on has been
7 directed to trucks although it would be obvious to one of
8 ordinary skill in the art to recognize that the teachings of
9 this patent and the associated claims may be directed to
to buses, boats, ambulances and so forth. Further, alternator
11 changes to address higher voltage systems may be substituted
12 throughout this specification and considered an obvious
13 variation within the scope of the patent. it is to be
~.4 understood that while z have illustrated and described ceri:ain
15 ~ forms of my ixivention, it is not to be limited to the specific
16 forms or arrangement of parts herein described and shown. It
17 will be apparent to thase skilled in the art that various
18 changes may be made without departing from the scope of the
19 ' invent~,on anal the invention is not to be considered limited to
20 what is shown in the drawings and described in the
21 specification.
z2
23
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