FR2570170A1 - DEVICE FOR AUTOMATICALLY CONTROLLING THE STARTING OF A EMERGENCY ENGINE FOR A REFRIGERATION FACILITY - Google Patents

Abstract

THE PRESENT INVENTION CONCERNS AN AUTOMATIC CONTROL DEVICE FOR THE STARTING OF A BACKUP MOTOR FOR A REFRIGERATION INSTALLATION. THIS DEVICE IS CHARACTERIZED IN THAT IT INCLUDES 30 MEANS FOR DETECTING THE TEMPERATURE OF A CHARGE CONTAINED IN THE REFRIGERATION SYSTEM, MEANS 26 FOR STARTING THE DRIVE MOTOR 12 OF THE MEANS 100 FOR CONNECTING THE INSTALLATION OF REFRIGERATION TO A SOURCE 16 OF ELECTRIC ENERGY AND TO DISCONNECT THE DRIVE MOTOR 12, MEANS 20 TO MONITOR THE SOURCE OF ELECTRIC ENERGY 16 AND MEANS 22, 24, 26, 18 TO DISCONNECT THE SOURCE OF ENERGY ELECTRICAL 16 AND TO COMMISSION THE DRIVE MOTOR 12 WHEN DETECTION OF A FAILURE OF THE ELECTRIC ENERGY SOURCE 16 AND OF A SIMULTANEOUS TEMPERATURE OF THE CHARGE REACHING A PREDETERMINED FIRST TEMPERATURE.

Description

The present invention relates to an automatic control device of the

starting an emergency engine

  for a refrigeration installation.

  In the refrigeration plant which contains

  of perishable goods in a situation usually isolated and off-road

  the place a center for grouping trucks or similar

  it is currently standard practice to operate

  the diesel engine of a truck in a manner similar to that of a domestic refrigerator, by rotating the engine automatically and cyclically. Essentially, instead of providing continuous cooling, the engine is started when the temperature of the charge reaches a first point and continues to operate until the charge temperature is brought below a second point at which case the engine is stopped. The engine is

  started by an automatic restart module. This function

  cyclical economy is economical from the point of view of

  fuel because the engine is not running

  no longer than it is necessary. However,

  that a power supply is available, it is often

  cheaper to operate the refrigeration system from the electrical mains, like a domestic refrigerator, but this puts the diesel engine and the restart module out of service

  automatic. When switching off the power supply

  that the device is taken out of service and can not function

  before the power supply has been restored

in a proper way.

  3 i A refrigeration plant according to the invention

  with an automatic restart module, is equipped with an automatic auxiliary

  supply the electric motor of the refrigeration

  in the event of an interruption of the power supply

  triqje. This device consists of a controller of

  three-phase power supply and an automatic control device

  start-up of a spare engine. When an

  dual-drive refrigeration system should function

  In a lonely manner, the electric motor acts in time as the main driving member for moving the refrigeration compressor. In the case of a break

  of the power supply, the control device

  Emergency Engine Start Detects the absence of electrical energy. If, while an absence of energy

  electrical system is detected, the installation requires a cooling

  the control device of the installation is

  switched from the drive by the electric motor to the en-

  iD drive by the diesel engine and the automatic restart module ensures the start of the diesel engine. The diesel engine then acts as an auxiliary engine for

  drive the compressor from the refrigeration plant.

  If the appropriate power supply is restored for the

  electric motor, the device then returns to a

  from the electric motor after the requirements

  relating to the temperature of the charge have been satisfied.

  When the ambient temperature is below the desired temperature, the device can provide a heating function to maintain the appropriate temperature of the heater.

load.

  An object of the present invention is to provide a

  automatic switching on an auxiliary drive motor

  in the event of a power failure

than. -

  Another object of the present invention is to provide

  an auxiliary device for refrigeration installations

  ration of trucks / trailers equipped with emergency engines.

  Another object of the present invention is to provide

  an automatic control device for the starting of an emergency engine which ensures a return to

  normal when the correct three-phase power supply has been

  tahiie. These and other purposes will become apparent

  subsequently, are obtained by the present invention.

  Essentially the automatic restart module cyclically powers the diesel engine on and off to provide air conditioning as required. When the refrigeration plant is connected to a source

  or h an alternative current line, the presence of the

  Electrical power is monitored and when a power supply is detected in any phase or phase that anyone of three-phase conductors, or even in the case of the detection of a low voltage, the automatic restart mode switches installing way

  that it be driven 8. from the engine diesei. If the food

  correct electrical power is restored, the refrigeration instalation is reduced to a power supply from

  sector once the requirements for cooling have been

  heating or heating were met.

  Hereinafter, by way of non-limiting example, an embodiment of the present invention will be described with reference to the accompanying drawing, in which:

  Figure 1 is a schematic diagram of an instal-

  dual-drive refrigeration system using the

  automatic auxiliary device according to the invention.

  FIGS. 2A-2D are electrical diagrams of the automatic control device for starting an emergency engine, the refrigeration installation being in the

off position.

  In FIG. 1 the reference 10 indicates the compres-

  refrigeration unit of a refrigeration plant.

  The compressor 10 is part of a refrigeration unit and it

  is operated operationally with a diesel engine 12 of the

  by means of a drive belt 11, and to an electric motor 14, via a driving belt 13, so that the compressor 10 can be driven either by the diesel engine 12 either by the electric motor 14. The belt 11. is connected to the motor] 2

  through a centrifugal clutch (not shown).

  100), used as an impeller when the motor 14 is powered from the three-phase power source 16

  yes is usually the sector of electrical supply.

  The power source 16 is connected to the motor there via a second motor contactor 18 having motor contacts 18a-d. The motor contact] 8d

  2C and is used as an internal component.

  switch in the low voltage control circuit. The automatic engine start-up device 100 is powered by the engine battery and comprises a power detection relay 20 having three inputs 20a, 20b, 20c respectively connected to the lines 16a, 16b, 16c respectively associated with the three phases. of the three-phase power supply. The power detection relay 20 serves as a power supply controller and is connected to the emergency engine n start automatic control device 22 to provide a signal thereto whenever a power failure occurs. in any phase or a low voltage condition is detected. The automatic starting device of the emergency engine 22 has two alternative outputs. The first output is provided,

  by a line 22a, to a control device 24 of entral-

  by the electric motor, which is connected by a line 24a to the solenoid 19 of the contactor relay 18.

  The output provided by line 24a is necessary to enable

  be the operation of the installation with a drive

  electrical so that the motor 14 is powered.

  Although this is not specifically illustrated,

  Represented by the example line 24a also include a channel controlling either heating or cooling, as well as control signals.

  to control the refrigeration system as represented

  by the slave valves SV1, SV2 and SV3 which appear

  Figure 2D. The second output of the control device 22 is applied, via a line 22b, to a drive control device 26 by the

  M0 diesel engine which includes the automatic restart module

  and 26, which is connected via lines 26a-c to the diesel engine 12. The outputs provided by lines 26a-c are necessary to start and control the diesel engine, as is the case with

  usual way with a control by restart module

  automatically, as well as the outputs necessary for the operation of the engine, which typically include

  outlets for solenoid glow plugs from mar-

2570 1 70

  the solenoid of speed, the launch of the engine, the

  heating relay and the evaporator motor. These outputs

  and the output represented by line 24a, also include a channel controlling either heating or cooling, as well as control signals.

  to control the refrigeration system as represented

  Servo valves SV1, SV2 and SV3. A sensor 30

  charge temperature control raises the tempera-

  the load information and provides the corresponding information 24 and 26 drive control devices respectively by the electric motor and the diesel engine, which are shown as separate but usually part of a single device

or circuit.

  The operation of the installation shown in Figure 1 is performed either from the diesel engine 12 or from the electric motor 14 acting as a drive motor of the refrigeration compressor 10

  in response to a request for cooling (or heating)

  ge) detected by the temperature sensor of the load 30. The compressor 10 is put into operation each time the temperature of the load reaches a first temperature and is kept running until the temperature of the load is lowered. at a second temperature lower than the first, when the operation takes place in the cooling mode. The compressor 10 is connected to the diesel engine 12 via the drive belt

  11 and a centrifugal clutch (not shown) function-

  Freewheeling each time the electric motor 14 is the drive motor in use. The compressor 10

  is also connected to the electric motor 14 by the interme-

  belt 13 and in the absence of an elec-

  the rotors (not shown) of this motor rotate

  freely when the diesel engine 12 is the driving force

  in-service training. The automatic control device 100

  the starting of the emergency engine controls the function

  compressor 10 in all modes of operation.

  off road transport, by starting up the

  diesel engine 12 or by starting the electric motor

  14 in response to load temperature conditions detected by the temperature sensor 30. When the refrigeration plant is connected to the power supply sector, this power supply sector is monitored by the power detection relay. 20 and if the power supply is correct, the device 22 for automatic start control of the motor 22 delivers a signal to the

  device 24 for driving control by the electric motor

  which in turn, when the temperature requirements of the load so require,

  solenoid 19 of the motor contactor relay 18, by the in-

  from line 24a, in order to provide electricity for

  from the power source 16 to the motor

  14, which then drives the compressor 10 tan-

  say that the centrifugal clutch of the diesel engine runs fast. If the power sensing relay 20 is

  a break in the power supply on any one

  16a-16c lines or a low voltage condition, a signal representing this case is provided to the device 22 for automatic control of the start of the diesel engine. This device 22 then emits a first signal towards the

  24 device for driving control by the electric motor

  which causes the contacts 18a-d of the motor contactor to open thereby cutting off the power supply of the electric motor 14. In addition the control device 22 provides

  a second output to the control device 26

  the diesel engine and, if a requirement for

  simultaneous cooling (or heating) is detected by the sensor 30, signals are provided via the

  lines 26a-26c for causing the diesel engine 12 to start.

  This motor 12 continues to rotate until the conditions

  temperature requirements are met, even if the power supply is restored while the

  motor 12 is running.

  The automatic start control device

  an emergency engine serves as an auxiliary device

  on truck refrigeration instalation

  morques equipped with emergency engines. This controller changes the operating mode of the refrigeration plant from an electric motor drive to a diesel engine drive in the event of a power failure or

  the appearance of a low voltage. If the electricity supply

  Once re-established and if the temperature requirements are met,

  the load is satisfied, the control device

  then returns to the electric motor drive when cooling or heating is to take place, the

  other conditions remaining constant.

  The power detection relay 20, the disc

  22 emergency automatic start of the emergency engine and the drive control device 24

  electric motors are integrated into the defined circuits.

  The invention also relates to the fact that the electrical connections between the elements defining the present invention do not constitute a part of the present invention. Referring now to FIGS. 2A-D, it can be seen that the automatic control device for starting the emergency engine

  consists of a number of circuits and

  which are assigned references 22-1 to 22-5 since, as indicated, they are found to be integrated

  in existing circuits and they are thus separated. AIN-

  if, as is conventional for a refrigeration installation d. 'a diesel truck, the whole of the

  circuit includes a 12 volt BTY battery, an alterna-

  ALT, circuit breakers CB-1, CB-2 and C-3, an EM evaporator fan motor, an EMR evaporator motor relay having a. contact EMR-1 and a fuel pump FP. Other components consist of a high-pressure switch HP1, normally closed, a heating relay HR having a contact HR-1, a

  safety switch OP controlling the pressure of the oil

q

  the engine is normally open, the switch

  nPS, which controls the pressure of emergency oil, normally

  closed shutter, a self-operating RS, a SCS speed controlled solenoid, an IF starter motor, a 5R speed relay having SR-1 and SC-2 contacts and a SS starter solenoid having an SS contact -1. Additional components are constituted by a lamp of

  APL automatic restart, a defrost air switch

  DA, GDS preheating-de-icing switch, a servo-controlled pressure control valve SV1, normally open, a servo valve SV2, normally closed, a hot gas servo valve

  SV3, normally closed, a temperature selector (thermo-

  mostat) TS'P, and a water temperature switch 1'T

normally closed.

  Referring now to FIGS. 20-D, SSW-1 and SSW-2 selector switches are each arranged in the emergency position which is indicated by the contacts S to be connected to the motor which is indicated by the contacts.

  E. However, the contact E of the SSI-2 switch is connected to

  and serves as an "out of service" position. The commons

  The EAS-1, EAS-2 and EAS-3 motor start motors are placed in the automatic position designated by the AUTO contacts instead of in the manual position designated by the MAN contacts, although the switches

  EAS-1 and EAS-2 are connected to the restart module

  tomatic ARM. The switch EAS-3 is connected to the AIUTO contact which does not lead anywhere and is thus in an "open" position with respect to the contact MAN which deactivates the automatic restart mode ARM. The SRS start-stop jog switch is placed in the on position indicated by the RU contacts. If we assume that the installation works normally in

  "rescue", it ensures cooling or heating

  as is required, in order to maintain the tempera-

  the load. If a power failure occurs in the totality of any of the 16a-16c conductors of the three-phase supply leads, or if a low-voltage condition exists, this is detected by the sensing wire of the power supply. supply 20 so that the PDR-1 working contact of this relay opens and the PDR-2 rest contact of the same reiais closes. If the power supply is present on all three phases of the power supply, then the PDR-2 contact is opened, thus preventing the flow of current to the relay OR, which thus causes the OR-1 contact to close and the contacts flR-2 and

OR-3 to open.

  RDT-1 and RDT-2 recycling timers are

  physically identical components but which are

  nected differently to obtain different results.

  The timer RDT-1 controls the ORT timer relay so that, if the timer RDT-1 is plugged in, it remains open for five minutes if

  although the ORT relay is not energized during this period.

  Period. The RDT-2 timer prevents cyclic short-period operation of the standby engine by preventing the engine from starting for a period of five minutes

  after it was recently cut off as a result of the

  motor contactor relay 18. Thus, if the installation

  refrigeration requires cooling (or heating) as it is relieved by the sensor that provides

  the signal indicating this fact to the temperature control module

  TCM, and if the RDT-2 does not prevent start-up due to a five-minute delay, to prevent cyclic operation at

  short period by keeping the contacts of the re-

  motor contactor 18, a current is supplied to the

  walk RR, through the PDR-2 contact and through

  to the SSW-2 selector switch to energize the

  The OR relay contact nR-1 opens while the nR-2 and OR-3 contacts close to "latch" the solenoid of the OR relay, the only way to bring the relay to rest. solenoid of the relay OR is to stop the commissioning of the installation by the idling of the RR walkway.The refrigeration instaiiation must pass through a compiet automatic start cycle before

  to return to the state of emergency. This ensures that the requirements

  these are met and the BTY battery is fully charged before the installation

return to the rescue position.

  At the same time as the control unit OR is energized, the timer circuit RDT-1 is energized, a current is prevented from energizing the ORT and therefore the nRT-1 contact. is closed

for a minimum of five minutes.

  A current flows through the ORT-1 contact,

  firing from the C terminal to the E terminal of the SSW-1 switch, through the automatic start switch of the

  EAS-2 engine to energize the self-restarting module.

  ARM. When the GPR-1 contact of the GRP glow plug relay closes (approximately 50 milliseconds after the ARM module has been energized), glow plugs of which only the candles GP-1 to GP-3 are shown as example, are excited and a current flows in

  direction of the RR, which leads to the closure of

  contacts RR-1 and RR-2, and through the encircling circuit of the RDT-2 timer. The contact of this timer RDT-2 then de-energizes the entire back-up circuit. The RR power relay remains energized through the ARM module before the backup circuit is de-energized

  to prevent a relay beat.

  After about thirty seconds, the restart module

  ARM automatic raging must start the instaliation on the basis of a drive by the diesel engine. When the engine starts to turn, the safety switch

  OPS pressure sensitive oil pressure which is normal-

  closed, opens and acts as a security

  re to de-energize the backup circuit. If the installation has started in the appropriate manner at the first attempt, the unit will operate in the autostart mode of the diesei engine until the following conditions are satisfied: 1) the instaliation has been running for a minimum of eight minutes; 2) the battery has been brought back to a full range state; and 3) the thermal sensor 30a requests a stop, by cutting the circuit of the relay RR and opening the contact RR-1. All the Ioric circuit is then brought back to the emergency state, to wait for the first signal. ie sensor 38

  asks for a new cycle of walking. If the triple feed

  appropriate phasing has been established, the installation will restart when the backup circuit is If the three-phase power supply is still off, the installation then repeats the cycle and starts a new automatic start cycle of the diesel engine. If instaiiation fails to start after three start attempts, a circ.ji; Defaulter is energized so that the fault relay FR and the fault lamp FL are excited. The working contact FR-2 closes while maintaining the solenoid of the relay FR and the lamp FL is kept lit until reset.

  manielie effected by means of switch start-march-

  SRS stop. The minimum closing time of five minutes for the ORT-1 contact ensures that three start attempts can be made, if necessary. At the same time as the contact FR-2 closes, the idle contact FR-1 opens which causes the interruption of any charge on the battery BTY, with the exception of the fault relay FR, of the fault lamp. FL and the lamp supply PL present. The instaiiation can then operate only on the emergency circuit and only if the three-phase power supply

  has been reinstated, ie if the PDR-1 contact is closed.

  The ARM automatic restart module is idle after three attempts failed to start the instalation until a

  3P zero using the SRS switch. The lamp of

  present PL is still in service as a

  orcaution, to warn that three-phase

  It should be reinstated in the command cabinet at any moment. According to one variant, the OR control signal can be delayed in order to prevent switching in ie

  case of a momentary interruption of the power supply.

  REVE'NDTiCATIPNS t.- Automatic start control device

  a back-up engine for a refrigeration plant

  comprising a main drive motor and adapted to be connected to a source of electrical energy, characterized in that it comprises means (3r.) for detecting the temperature of a charge contained in the refrigerationinstation. . means (26) to make

  start the drive motor (12) when the temperature

  The detected chariee reaches a first temperature

  predetermined and to keep running the motor of

  (12) until the temperature of the detected gas reaches a second predetermined temperature, means (inR) for connecting the refrigeration system to a source (16) of electrical energy and for decommissioning the engine (12), means (20) for monitoring the source of electrical energy (16) and means

  22,24,26,18) .to disconnect the electrical energy source

  that (16) and to operate the drive motor (12) upon detection of a failure of the power source (16) and a simultaneous temperature of the load reaching the first predetermined temperature, such that the means (26) for starting the drive motor (12) are energized and this driving motor operates until the temperature of the drive motor (12) is reached.

  the detected load reaches the second predetermined temperature.

undermined.

  2. Device according to claim 1,

  in that it also includes means for recognizing

  3n connect the power source (16) and put

  when the drive motor (12) is out of service when

  restoration of the source of electrical energy and

  stopping the drive motor (12) after the timing

  the detected load reached the second temperature.

re predetermined.

  3. A process for automatically starting an out-of-service drive motor from a re-inertia instalation when a power source source connected to said refrigeration plant is de-energized, characterized in that it comprises the steps of connect the refrigeration instation to an electrical power source (16), disable the drive motor (12), detect the charge temperature in the refrigeration plant, monitor the source of electrical energy (16) and, upon detection of a failure of the power source (16), decon-

  the power source (16) is switched on and in operation and the drive motor (12) is started if the temperature of the detected load has reached a first

predetermined temperature.

  4. Process according to claim 3, characterized

  in that it further comprises the steps of recognizing

  the power source (16) is switched off and the drive motor (12) is switched off when the recovery of the power source (16) is detected and

  stopping the drive motor (12) after the

  the detected charge has reached a second

predetermined height.

  5. A process according to claim 3 characterized in that the step of monitoring the source of electrical energy (16) comprises the detection of a condition to

low tension.