GB2164433A - Automatic emergency engine starting system - Google Patents
Automatic emergency engine starting system Download PDFInfo
- Publication number
- GB2164433A GB2164433A GB08521179A GB8521179A GB2164433A GB 2164433 A GB2164433 A GB 2164433A GB 08521179 A GB08521179 A GB 08521179A GB 8521179 A GB8521179 A GB 8521179A GB 2164433 A GB2164433 A GB 2164433A
- Authority
- GB
- United Kingdom
- Prior art keywords
- prime mover
- source
- electrical power
- temperature
- load
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Granted
Links
Classifications
-
- H—ELECTRICITY
- H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
- H02J—CIRCUIT ARRANGEMENTS OR SYSTEMS FOR SUPPLYING OR DISTRIBUTING ELECTRIC POWER; SYSTEMS FOR STORING ELECTRIC ENERGY
- H02J9/00—Circuit arrangements for emergency or stand-by power supply, e.g. for emergency lighting
- H02J9/04—Circuit arrangements for emergency or stand-by power supply, e.g. for emergency lighting in which the distribution system is disconnected from the normal source and connected to a standby source
- H02J9/06—Circuit arrangements for emergency or stand-by power supply, e.g. for emergency lighting in which the distribution system is disconnected from the normal source and connected to a standby source with automatic change-over, e.g. UPS systems
- H02J9/066—Circuit arrangements for emergency or stand-by power supply, e.g. for emergency lighting in which the distribution system is disconnected from the normal source and connected to a standby source with automatic change-over, e.g. UPS systems characterised by the use of dynamo-electric machines
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F25—REFRIGERATION OR COOLING; COMBINED HEATING AND REFRIGERATION SYSTEMS; HEAT PUMP SYSTEMS; MANUFACTURE OR STORAGE OF ICE; LIQUEFACTION SOLIDIFICATION OF GASES
- F25B—REFRIGERATION MACHINES, PLANTS OR SYSTEMS; COMBINED HEATING AND REFRIGERATION SYSTEMS; HEAT PUMP SYSTEMS
- F25B27/00—Machines, plants or systems, using particular sources of energy
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F02—COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
- F02B—INTERNAL-COMBUSTION PISTON ENGINES; COMBUSTION ENGINES IN GENERAL
- F02B3/00—Engines characterised by air compression and subsequent fuel addition
- F02B3/06—Engines characterised by air compression and subsequent fuel addition with compression ignition
Landscapes
- Engineering & Computer Science (AREA)
- Business, Economics & Management (AREA)
- Emergency Management (AREA)
- Power Engineering (AREA)
- Physics & Mathematics (AREA)
- Mechanical Engineering (AREA)
- Thermal Sciences (AREA)
- General Engineering & Computer Science (AREA)
- Control Of Vehicle Engines Or Engines For Specific Uses (AREA)
- Devices That Are Associated With Refrigeration Equipment (AREA)
Abstract
A refrigeration unit having a dual drive is provided with an automatic switchover from line power to diesel in the event that electric power is interrupted and there is a heating/cooling demand. <IMAGE>
Description
SPECIFICATION
Automatic emergency engine starting system
Background of the Invention
In refrigeration, or reefer units, which are carrying a perishable load in a usually unattended, non-highway condition as at a truck terminal or the like, it is now a standard practice to operate the truck diesel engine in a fashion similar to that of a home refrigerator by automatically cycling the engine. Basically, rather than supplying continuous cooling, the engine is started when the load temperature reaches a first point and continues to run until the load temperature is brought down to a second point whereupon the engine is shut off. The engine is started by the automatic restart module (ARM). This cycling is fuel efficient in that the engine does not run longer than is necessary.Where line power is available, however, it is often more economical to operate the reefer unit from line power in the described fashion of a home refrigerator, but this disables the diesel engine and the ARM. Upon interruption of the line power, the system is shut down and will not operate until there is a restoration of proper power.
Summary of the Invention
A reefer unit with an ARM is provided with an automatic back-up system for powering the electric motor of the reefer unit in the event of a power outage. The system consists of a three-phase power monitor and an Automatic
Engine Starting Controller. When a dual drive refrigeration unit is to be operated unattended, the electric motor acts as the prime mover in powering the refrigeration compressor. In the event of a power outage, the automatic emergency engine starting system senses the power loss. If while a power loss is sensed, the system requires cooling, the unit's control system is changed from electric motor drive to diesel engine drive and the ARM proceeds to start the engine. The diesel engine then acts as a back-up prime mover for powering the refrigeration compressor.If proper electric power is restored to the electric motor, the system would revert back to electric motor drive after cargo temperature requirements are satisfied. Where the ambient temperature is below the desired temperature, the system may provide a heating function to maintain the proper load temperature.
It is an object of this invention to provide an automatic switchover to a back-up prime mover upon the interruption of line power.
It is another object of this invention to provide a back-up system on truck/trailer units equipped with standby motors.
It is a further object of this invention to provide an automatic emergency engine starting system which reverts back to standby operation when proper three-phase power has been restored. These objects, and others as will become apparent hereinafter, are accomplished by the present invention.
Basically, the ARM cycles the diesel engine on and off to supply conditioned air, as required. When the unit is connected to an alternate power source/line power, the supply power is sensed and, upon the sensing of a power loss, in all, or any one leg, of the three-phase power leads, or upon the sensing of a low voltage condition, the ARM switches over the system to diesel power. If proper line power is restored, the unit is switched back to line power once the current cooling, or heating, requirements are satisfied.
Brief Description of the Drawings
For a fuller understanding of the present invention, reference should now be made to the following detailed description thereof taken in conjunction with the accompanying drawings wherein:
Figure 1 is a schematic representation of a dual refrigeration unit employing the automatic back-up system of the present invention; and
Figures 2A-D are a circuit diagram of the automatic engine starting controller with the unit in the "off" position.
Description of the Preferred Embodiments
In Fig. 1, the numeral 10 designates the refrigeration compressor of a reefer unit. Compressor 10 is part of a refrigeration system and is operatively connected to the unit diesel engine 12 via drive belt 11 and to electric motor 14 via drive belt 13 whereby compressor 10 can be driven by either engine 12 or motor 14. Belt 11 is connected to engine 12 via a centrifugal clutch (not illustrated) which freewheels when motor 14 is powered by three-phase power source 16 which would ordinarily be line power. Power source 16 is connected to motor 14 via motor contactor 18 relay having motor contacts 18a-d. Motor contact 18d appears in Fig. 2c and serves as a switching device in the low voltage control circuit.The automatic emergency engine start system 100 is powered by the engine battery and includes a power detection relay, or PDR, 20 having three inputs 20a-c connected, respectively, to lines 1 6a c, which each respectively, carry one-phase of the three-phase power. Power detection relay, PDR, 20 serves as a power monitor and is connected to auto matic engine starting controller 22 and supplies a signal thereto whenever a loss of power in any phase, or a low voltage condition is detected. Automatic engine starting controller 22 has two alternative outputs. The first output is supplied via line 22a to electric drive control system 24 which is connected via examplary line 24a to solenoid 19 of motor contactor 18. The output supplied via line 24a is necessary for operation of the system on electric drive whereby motor 14 is powered.Although not specifically illustrated, the outputs represented by exemplary line 24a would also include a direction calling for either heating or cooling as well as control signals to control the refrigeration system as represented by servo valves SV1, SV2 and SV3 which appear in Fig. 2D. The second output is supplied via line 22b to engine drive control system 26 which includes the ARM and is connected via exemplary lines 26a-c to engine 12. The outputs supplied via exemplary lines 26are are necessary for starting and controlling the engine, as is standard with ARM control, as well as the outputs needed for engine operation which, typically, include the glow plugs, run solenoid, speed solenoid, start motor cranking, heating relay and evaporator motor.These outputs, like the output, represented by exemplary line 24a would also include a direction calling for either heating or cooling as well as control signals to control the refrigeration system as represented by servo valve SV1, SV2 and SV3. A load temperature control sensor 30 senses the temperature of the load and supplies the information to electric and engine drive control systems 24 and 26, respectively, which are illustrated as separate but would ordinarily be part of a single device or circuit.
The operation of the Fig. 1 system would be with either engine 12 or motor 14 as the prime mover for driving refrigeration compressor 10 in response to a cooling (or heating) demand sensed by load temperature sensor 30. The compressor 10 is operated whenever the temperature of the load reaches a first temperature and is kept running until the load temperature is brought down to a second temperature which is lower than the first temperature, when operating in the cooling mode.
Compressor 10 is connected to engine 12 via drive belt 11 and a centrifugal clutch (not illustrated) so that it freewheels whenever motor 14 is the prime mover. Compressor 10 is also connected to electric motor 14 via drive belt 13 and, in the absence of an electric field, the rotors (not illustrated) freely rotate when diesel benzine 12 is the prime mover. The automatic emergency start system 100 controls the operation of compressor 10 in all modes of non-highway operation by starting engine 12 or running motor 14 in response to load temperature requirements sensed by temperature sensor 30.When the reefer unit is connected to line power, the line power is monitored by PDR 20 and, if correct, automatic engine starting controller 22 provides a signal to electric drive control system 24 which, in turn, when load temperature requirements demand, operates coil 19 of motor contactor 18 via exemplary line 24a to cause power from power source 16 to be supplied to electric motor 14 which drives compressor 10 while the centrifugal clutch of engine 12 freewheels.
If PDR 20 detects an interruption of power in any one of lines 16a-c, or a low voltage condition, a signal indicative thereof is supplied to automatic engine starting controller 22. Controller 22 would then send a first signal to electric drive control system 24 which would cause motor contactors 18a-d to be disabled thereby disabling electric motor 14.
Additionally, controller 22 would furnish a second output to engine drive cpntrol system 26 and, if a simultaneous cooling (heating) requirement is detected by sensor 30, signals are provided via exemplary lines 26are thereby causing engine 12 to be started. Engine 12 would continue to run until the temperature requirement is satisfied, even if line power is restored while engine 12 is running.
The automatic emergency start system serves as a back-up system on truck/trailer units equipped with standby motors. The system changes the operating mode of the unit from electric drive to engine drive in the event of a power outage or a low voltage condition.
If power is restored and cargo temperature requirements are satisfied, the system would return to electric drive when a cooling (heating) need arises, other conditions remaining constant.
The PDR 20, automatic engine starting controller 22 and electric drive control system 24 are integrated into the circuits defining the engine drive control system 26 so that the electrical connections between the members defining the present invention do not form a part of the present invention. Referring now to
Figs. 2A-D, automatic engine starting controller 22 is made up of a number of circuits and components which are labeled 22-1 through 22-5 since, as noted, they are integrated into existing circuits and are separated thereby.
Thus, as would be conventional for a reefer unit for a diesel truck, the circuitry includes a 12 volt battery BTY, alternator ALT, circuit breakers CB-1, CB-2 and CB-3, evaporator fan motor EM, evaporator motor relay EMR having contacts EMR-1 and fuel pump FP. Other components include normally closed high pressure cut-out switch HP1, heat relay HR having contacts HR-1, normally open engine oil pressure safety switch OP, normally closed standby oil pressure safety switch OPS, run solenoid RS, speed controlled solenoid SCS, starter motor
SM, speed relay SR having contacts SR-1 and
SR-2 and starter solenoid SS having controls
SS-1. Additional components include auto restart light ARL, defrost air switch DA, glowdefrost switch GDS, normally open condenser pressure control servo valve So 1, normally closed liquid servo valve SV2, normally closed hot gas servo valve SV3, temperature selector (thermostat) TSP, and normally closed water temperature switch WT.
Referring now the Figs. 2 A-D, in operation, selector switches SSW-1 and SSW-2 are each placed in standby which is designated by con tacts S rather than being connected to the engine which is designated by contacts E.
However, contact E of switch SSW-2 is not connected to anything and serves as an "off" position. The engine automatic start switches EAS- 1, and EAS-3 are placed in the automatic position designated by contacts AUTO, rather than the manual position designated by contacts MAN, whereby switches EAS-1 and
EAS-2 are connected to ARM. Switch EAS-3 is connected to contact AUTO which does not lead anywhere but is in an "off" position relative to contact MAN which disables the
ARM. The ganged start-run-stop switch SRS is placed in the run position designated by contacts RUN. Assuming that the unit is operating normally in the "standby" mode, it will cool or heat, as required, to maintain the load temperature.If a power failure occurs in all or any one of legs 16are of the three-phase power leads, or if a low voltage condition exists, it is detected by power detection relay,
PDR 20 and normally open contacts PDR-1 open and normally closed contacts PDR-2 close. If all three legs of power are present contacts PDR-2 would be open, thus preventing the flow of power to override relay OR thereby causing contacts OR-1 to close and contacts OR-2 and OR-3 to open.
Recycle delay timers RDT-1 and RDT-2 are physically identical components, but they are connected differently to achieve different results. RDT-1 controls time delayed override relay ORT in that if RDT-1 is triggered it remains open for five minutes so that ORT is not energized. RDT-2 prevents short cycling of the standby motor by inhibiting the motor from starting for five minutes after it was last shut off by controlling motor contactor relay 18.Thus, if the reefer unit is requiring cooling (or heating) as sensed by sensor 30 which furnishes a signal indicative thereof to temperature control module TCM, and if recycle delay timer RDT-2 is not preventing starting due to a five minute delay to prevent short cycling by keeping the contacts of motor contactor relay 18 open, current is supplied to run relay
RR, through contacts PDR-2, through selector switch' SSW-2 to energize the override relay,
OR, coil. OR contacts OR-1 open while contacts OR-2 and OR-3 close "latching" the OR coil. The only way that OR coil can drop out is if the unit shuts down by dropping out the run relay RR. The reefer unit must go through one complete auto-start cycle before returning to standby. This insures that temperature requirements are satisfied and the battery BTY is fully charged before the unit returns to standby.
At the same time that override relay OR is energized, the trigger circuit of RDT-1 is energized, current is prevented from energizing the coil of ORT, thus contacts ORT-1 are closed for a minimum of five minutes.
Current flow through ORT-1 from common terminal C to terminal E of SSW-1 through engine automatic start switch EAS-2 to energize the auto-restart module ARM. When contacts GPR-1 of glow plug relay GRP close (approximately 50 milliseconds after ARM is energized) glow plugs, of which GP-1 to 3 are exemplary, are energized and current flows to run relay RR, causing contacts RR-1 and 2 to close, and through the trigger circuit of RDT2. The contacts of RDT-2 then de-energizes all standby circuitry. Run relay RR remains energized through the ARM before the standby circuitry is de-energized to prevent a relay race.
After about thirty seconds, the ARM should start the unit on engine drive. When the engine starts cranking, normally closed, pressure responsive, oil pressure safety switch, OPS, opens and acts as a back-up safety to deenergize the standby circuitry. If the unit started properly on the first attempt, the unit would run in the engine auto-start mode until the following conditions were met: (1) the unit had run for a minimum of eight minutes; (2) the battery was restored to a fully charged condition; and (3) thermal sensor 30 called for a shutdown, breaking the run relay circuit RR and opening contacts RR-1. All logic would then switch back to standby and await sensor 30 calling for another run. If proper threephase power had been re-established, the unit would restart on standby.If the three-phase power was still off, the unit would repeat the cycle and run another engine auto start cycle.
If the unit failed to start after three starting attempts, fault circuitry is energized whereby fault relay FR and fault light FL are energized.
Normally open contacts FR-2 close thereby latching the coil of FR and FL is kept lit until manually reset with start-stop-run switch SRS.
The five minute minimum closure time for the contacts ORT-1 insures that three starting attempts can be made, if necessary. At the same time that contacts FR-2 are closed, normally closed contacts FR-1 are opened deenergizing any load on unit battery BTY except for fault relay FR, fault light FL and power-on light PL. The unit can then only operate on standby and only if three-phase power has been re-established, i.e. contacts
PDR-1 close. The ARM is inoperable after three attempts have failed to start the unit until manually reset with SRS switch. Poweron light PL is always on as a safety precaution to warn that three-phase power could be re-established in the control box at any time.
Alternatively, override relay OR can be timedelayed to prevent a changeover for momentary power losses.
Although a preferred embodiment of the present invention has been illustrated and described, other changes will occur to those skilled in the art. It is, therefore, intended that the scope of the present invention is to be limited only by the scope of the appended
Claims (5)
1. In a refrigeration unit having a prime mover and adapted to be connected to a source of electrical power, an automatic emergency starting system comprising:
means for sensing the temperature of a load in said refrigeration unit;
means for starting said prime mover responsive to the sensed temperature of the load reaching a first predetermined temperature and for keeping said prime mover running until the sensed temperature of the load reaches a second predetermined termperature;
means for connecting said refrigeration unit to a source of electrical power and for disabling said prime mover;
means for monitoring said source of electrical power; and
means for disconnecting said source of electrical power and for enabling said prime mover upon a sensed failure of said source of electrical power and a concurrent sensed load temperature reaching said first predetermined temperature whereupon said means for starting said prime mover is activated and said prime mover is run until said sensed temperature of the load reaches said second predetermined temperature.
2. The automatic emergency starting system of claim 1 further comprising means for reconnecting said source of electrical power and for disabling said prime mover upon sensing the re-establishment of said source of electrical power and the stopping of said prime mover responsive to sensed load temperature reaching said second predetermined temperature.
3. A method for automatically starting a disabled prime mover of a refrigeration unit upon the failure of a source of electrical power connected to said refrigeration unit comprising the steps of:
connecting the refrigeration unit to a source of electrical power;
disabling the prime mover;
sensing the temperature of the load in the refrigeration unit;
monitoring the source of electrical power;
upon the sensing of a failure of the source of electrical power, disconnecting the source of electrical power and enabling and starting the prime mover of the sensed load temperature has reached a first predetermined temperature.
4. The method of claim 3 further including the steps of reconnecting the source of electrical power and disabling the prime mover upon the sensing of the re-establishment of the source of electrical power and the stopping of the prime mover responsive to sensed load temperature reaching a second predetermined temperature.
5. The method of claim 3 wherein said step of monitoring includes the sensing of a low voltage condition.
Applications Claiming Priority (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
US64958984A | 1984-09-12 | 1984-09-12 |
Publications (3)
Publication Number | Publication Date |
---|---|
GB8521179D0 GB8521179D0 (en) | 1985-10-02 |
GB2164433A true GB2164433A (en) | 1986-03-19 |
GB2164433B GB2164433B (en) | 1987-12-16 |
Family
ID=24605457
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
GB08521179A Expired GB2164433B (en) | 1984-09-12 | 1985-08-23 | Automatic emergency engine starting system |
Country Status (5)
Country | Link |
---|---|
BR (1) | BR8504397A (en) |
FR (1) | FR2570170B1 (en) |
GB (1) | GB2164433B (en) |
IE (1) | IE56760B1 (en) |
IT (1) | IT1185710B (en) |
Cited By (5)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US5487278A (en) * | 1994-05-06 | 1996-01-30 | Kenneth J. Hartman | Back-up switching system for refrigerator trucks |
US5501083A (en) * | 1993-10-19 | 1996-03-26 | Samsung Electronics Co., Ltd. | Control apparatus and method for an air conditioner compressor |
GB2293703A (en) * | 1994-09-27 | 1996-04-03 | Kirknalls Refrigeration | Mains failure protection for refrigerated loads |
EP0883225A1 (en) * | 1996-03-06 | 1998-12-09 | Tai Her Yang | System for automatic supervision of storage battery charge in an engine driven standby power unit |
US8590330B2 (en) | 2010-06-03 | 2013-11-26 | Thermo King Corporation | Electric transport refrigeration unit with temperature-based diesel operation |
Family Cites Families (11)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
USRE19858E (en) * | 1936-02-18 | Refrigerating apparatus | ||
US2015309A (en) * | 1934-02-16 | 1935-09-24 | Igarashi Tomehiko | Automatic starting and stopping apparatus for a diesel engine |
GB450581A (en) * | 1935-05-09 | 1936-07-21 | Petters Ltd | Improvements in and relating to the automatic starting and stopping of electric generating sets driven by internal combustion engines |
US2879757A (en) * | 1955-03-10 | 1959-03-31 | Asea Ab | Starting device for reserve aggregates driven by a combustion engine |
US3283525A (en) * | 1964-04-09 | 1966-11-08 | Westinghouse Electric Corp | Electrical control for a refrigeration system |
FR1567179A (en) * | 1968-02-14 | 1969-05-16 | ||
US3512373A (en) * | 1968-07-12 | 1970-05-19 | Transicold Corp | Refrigeration system with electric auxiliary prime mover |
US3926167A (en) * | 1971-08-26 | 1975-12-16 | Woods M Bruce | Starting circuit for engine utilizing fuel injection pump |
ES415942A1 (en) * | 1973-06-15 | 1976-02-01 | Rivera Macias | Automatic stopping and starting apparatus of industrial cold generators moved by gas-oil engine. (Machine-translation by Google Translate, not legally binding) |
US4467615A (en) * | 1982-01-15 | 1984-08-28 | Sencon Engineering Inc. | Control system for diesel powered refrigeration plant |
US4460834A (en) * | 1983-08-29 | 1984-07-17 | Power Group International Corp. | Uninterruptible power system |
-
1985
- 1985-08-23 GB GB08521179A patent/GB2164433B/en not_active Expired
- 1985-09-03 IE IE2167/85A patent/IE56760B1/en not_active IP Right Cessation
- 1985-09-10 FR FR8513407A patent/FR2570170B1/en not_active Expired
- 1985-09-11 BR BR8504397A patent/BR8504397A/en not_active IP Right Cessation
- 1985-09-12 IT IT22120/85A patent/IT1185710B/en active
Cited By (5)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US5501083A (en) * | 1993-10-19 | 1996-03-26 | Samsung Electronics Co., Ltd. | Control apparatus and method for an air conditioner compressor |
US5487278A (en) * | 1994-05-06 | 1996-01-30 | Kenneth J. Hartman | Back-up switching system for refrigerator trucks |
GB2293703A (en) * | 1994-09-27 | 1996-04-03 | Kirknalls Refrigeration | Mains failure protection for refrigerated loads |
EP0883225A1 (en) * | 1996-03-06 | 1998-12-09 | Tai Her Yang | System for automatic supervision of storage battery charge in an engine driven standby power unit |
US8590330B2 (en) | 2010-06-03 | 2013-11-26 | Thermo King Corporation | Electric transport refrigeration unit with temperature-based diesel operation |
Also Published As
Publication number | Publication date |
---|---|
IT8522120A0 (en) | 1985-09-12 |
FR2570170B1 (en) | 1988-02-12 |
IE56760B1 (en) | 1991-12-04 |
GB2164433B (en) | 1987-12-16 |
IT1185710B (en) | 1987-11-12 |
GB8521179D0 (en) | 1985-10-02 |
FR2570170A1 (en) | 1986-03-14 |
BR8504397A (en) | 1986-07-08 |
IE852167L (en) | 1986-03-12 |
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Legal Events
Date | Code | Title | Description |
---|---|---|---|
PCNP | Patent ceased through non-payment of renewal fee |
Effective date: 19960823 |