JP2016124454A - Air-condition control device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an air-condition control device that is able to restrict degradation in air-conditioning performance while restricting degradation in acceleration performance of a vehicle.SOLUTION: An air-conditioning control device 4 that controls, in accordance with an acceleration operation of a vehicle 1, an air-conditioner 3 having a compressor 21 driven by power of an internal combustion engine 2, comprises: an acceleration performance degradation detection unit 34 that, on the basis of a running state of the internal combustion engine 2, detects whether the acceleration performance has been degraded or not; and an air-conditioning control unit 32 that stops the drive of the compressor 21 on condition that acceleration performance detected by the acceleration performance degradation detection unit 34 has decreased.SELECTED DRAWING: Figure 1

Description

    The present invention relates to an air conditioning control device that controls an air conditioning device that is driven by the power of an internal combustion engine.

  In general, in a vehicle equipped with an air conditioner driven by the power of an internal combustion engine, when acceleration is performed while the air conditioner is driven, optimal acceleration is obtained due to the load on the internal combustion engine of the air conditioner. Acceleration performance is reduced. Therefore, when the vehicle is accelerating, control is performed to stop the air conditioner so that the internal combustion engine is not loaded, so that optimal air conditioning cannot be obtained and air conditioning performance deteriorates. There has been proposed an air conditioning control device that suppresses a decrease in air conditioning performance while suppressing such a decrease in acceleration performance.

  Conventionally, as this type of air-conditioning control device, a compressor driven by the power of an internal combustion engine, a clutch, a clutch control means, an acceleration start determination means for determining the start of an acceleration operation of the host vehicle, and an end of the acceleration operation are performed. A device including an acceleration end determination means for determining is known (see, for example, Patent Document 1).

The conventional air-conditioning control apparatus periodically disconnects the clutch by the clutch control unit from the start of acceleration determined by the acceleration start determination unit to the end of acceleration determined by the acceleration end determination unit, and compresses the power of the internal combustion engine by the compressor. To communicate intermittently.
Thereby, the conventional air-conditioning control apparatus is suppressing the fall of air-conditioning performance, suppressing the fall of the acceleration performance of the own vehicle.

Japanese Patent Laid-Open No. 2001-246828

  However, in the conventional air conditioning control device, when the acceleration start determining means determines that the host vehicle has started acceleration, the power of the internal combustion engine is intermittently transmitted to the compressor, and the power is continuously transmitted. Compared with the case where it is done, air-conditioning performance will fall. Even when the acceleration is started, depending on the operating state of the internal combustion engine, there may be variations such as when acceleration performance has a margin and when there is no margin. That is, depending on the operating state of the internal combustion engine, it may not be necessary to cut off the power transmitted from the internal combustion engine to the compressor.

  When there is a margin in such acceleration performance, the necessity for suppressing a decrease in acceleration performance is also reduced. When the necessity for suppressing such deterioration in acceleration performance is low, if the power transmitted from the internal combustion engine to the compressor is interrupted intermittently, the air conditioner is also intermittently turned off, resulting in a deterioration in air conditioning performance. .

  The present invention has been made to solve the above-described problems, and provides an air conditioning control device capable of suppressing a decrease in air conditioning performance while suppressing a decrease in acceleration performance of the host vehicle. This is the issue.

  In order to solve the above-described problems, the present invention provides an air conditioning control apparatus that controls an air conditioning apparatus having a compressor driven by the power of an internal combustion engine according to an acceleration operation of the host vehicle, based on an operating state of the internal combustion engine. The compressor is driven on the condition that the acceleration performance degradation detection unit for detecting whether or not the acceleration performance of the host vehicle is degraded, and the acceleration performance detected by the acceleration performance degradation detection unit is degraded. And an air conditioning control unit to be stopped.

  ADVANTAGE OF THE INVENTION According to this invention, the air-conditioning control apparatus which can implement | achieve suppression of the fall of air-conditioning performance can be provided, suppressing the fall of the acceleration performance of the own vehicle.

FIG. 1 is a schematic configuration diagram showing a configuration of an air conditioning control device according to an embodiment of the present invention. FIG. 2 is a flowchart showing a flow of air conditioning control of the air conditioning control device according to the embodiment of the present invention. FIG. 3 is a time chart of the air conditioning control of the air conditioning control apparatus according to the embodiment of the present invention.

Hereinafter, an air conditioning control device according to an embodiment in which an air conditioning control device according to the present invention is mounted on a vehicle 1 will be described with reference to FIGS. 1 to 3.
First, the configuration will be described.

  As shown in FIG. 1, the vehicle 1 according to the present embodiment includes an internal combustion engine 2, an air conditioner 3, an air conditioner control device 4, and an accelerator pedal 5.

  The internal combustion engine 2 is configured by a known internal combustion engine such as a four-cycle gasoline engine or a diesel engine that performs a series of four strokes including an intake stroke, a compression stroke, an expansion stroke, and an exhaust stroke. The internal combustion engine 2 includes an engine body 11, an intake pipe 12, an injector 13, and an exhaust pipe 14, and outputs power from a crankshaft (not shown).

The engine body 11 is composed of a structure such as a cylinder block, a cylinder head, a cylinder head cover, and an oil pan (not shown) in which a cylinder and a combustion chamber are formed.
The intake pipe 12 is connected to the engine body 11 via an intake manifold (not shown), and supplies intake air purified by an air cleaner into a cylinder formed in the engine body 11. The intake pipe 12 is provided with a throttle valve for adjusting the intake air amount between the air cleaner and the intake manifold.

  The injector 13 injects fuel supplied from a fuel tank into a cylinder or an intake port (not shown) communicating with the cylinder. The exhaust pipe 14 is connected to the engine body 11 via an exhaust manifold (not shown), distributes exhaust gas in the cylinder, and exhausts it into the atmosphere via a catalytic converter and a muffler. The engine body 11 is provided between the air cleaner and the intake manifold in the intake pipe 12 and is driven by the flow of the exhaust gas supplied from the exhaust pipe 14 to pressurize the intake air and supply it to the intake manifold. You may have.

  The air conditioner 3 includes a unit that performs air conditioning such as heating, cooling, dehumidification, and ventilation of a vehicle interior (not shown) of the vehicle 1, for example, an HVAC (Heating, Ventilating, and Air Conditioning) system. The air conditioner 3 includes a compressor 21, a clutch 22, and a blower fan (not shown).

  The air conditioner 3 is connected to the air conditioner control device 4, and the driving of the air conditioner 3 is controlled by the air conditioner controller 4, and air conditioning such as heating, cooling, dehumidification, and ventilation is performed in the passenger compartment.

  The compressor 21 is connected to the crankshaft of the internal combustion engine 2 via the clutch 22 and is driven by power output from the crankshaft of the internal combustion engine 2. The compressor 21 compresses and circulates a refrigerant in an evaporator (not shown).

  The clutch 22 is provided between the crankshaft compressor 21 of the internal combustion engine 2 and a transmission state in which the power of the internal combustion engine 2 is transmitted to the compressor 21 and a non-transmission state in which the power of the internal combustion engine 2 is not transmitted to the compressor 21. Switch. The switching operation of the clutch 22 is controlled by the air conditioning control device 4.

  The blower fan circulates air through an evaporator or a heater provided in an air flow path (not shown). When air flows through the evaporator, heat is exchanged between the refrigerant in the evaporator and the air, and the temperature of the air is lowered and sent to the vehicle interior that communicates with the air flow path. Heat is exchanged between the air and the air, the temperature of the air rises, and the air is sent to the passenger compartment communicating with the air flow path.

  The air conditioning control device 4 includes an electronic control unit (ECU: Electronic Control Unit) 31. The ECU 31 includes a microcomputer having a CPU (Central Processing Unit), a RAM (Random Access Memory), a ROM (Read Only Memory), a flash memory, an input port, an output port, and a network module. ing. The ECU 31 executes arithmetic processing based on data and programs stored in the ROM. The internal combustion engine 2, the air conditioner 3, and the injector 13 are connected to the output port, and a control signal from the ECU 31 is output.

  In addition, an intake air flow rate sensor 41, a wheel speed sensor 42, and an accelerator opening sensor 43 are connected to the input port of the ECU 31, and detection information of each sensor is transmitted to the CPU via the input port.

  The intake air flow rate sensor 41 is configured by a sensor that is provided in the intake pipe 12 and detects the flow rate of intake air flowing through the intake passage of the intake pipe 12, for example, an air flow sensor (MAF sensor: Mass Airflow sensor). The wheel speed sensor 42 is a sensor that detects the rotational speed of a wheel (not shown). The accelerator opening sensor 43 is a sensor that detects the amount of depression of the accelerator pedal 5 by the driver, that is, the accelerator opening.

  The ECU 31 includes an air conditioning control unit 32, an acceleration performance decrease detection unit 34, a soot reduction control unit 33, an excess air ratio calculation unit 35, and an operation state detection unit 36, respectively. The ECU 31 performs functions of the air conditioning control unit 32, the acceleration performance decrease detection unit 34, the soot reduction control unit 33, the excess air ratio calculation unit 35, and the operation state detection unit 36. These units may be connected by network (CAN: Controller Area Network) communication. The air conditioning control unit 32, the acceleration performance decrease detection unit 34, and the soot reduction control unit 33 of the embodiment constitute an air conditioning control device of the present invention that controls an air conditioning device having a compressor driven by the power of the internal combustion engine.

  The air conditioning control unit 32 switches the clutch 22 of the air conditioner 3 from the transmission state to the non-transmission state on the condition that the acceleration performance deterioration detection unit 34 detects that the acceleration performance of the vehicle 1 is deteriorated. Thus, the drive of the compressor 21 is stopped. When the drive of the compressor 21 is stopped, the air conditioner 3 is turned off, and the load due to the drive of the air conditioner 3 on the internal combustion engine 2 is eliminated. Thereby, the fall of the acceleration performance of the vehicle 1 is suppressed.

  The air conditioning control unit 32 measures a stop time from the start of stoppage of driving of the compressor 21 with a timer (not shown), and the measured stop time t (sec) of the compressor 21 is preset and stored in the ROM for a predetermined time T. It is determined whether or not (sec) has been exceeded, that is, whether or not t> T is satisfied. When it is determined that t> T is satisfied, the air conditioning control unit 32 switches the clutch 22 of the air conditioner 3 from the non-transmission state to the transmission state, and transmits power from the internal combustion engine 2 to the compressor 21. As a result, the compressor 21 is driven and the air conditioner 3 is turned on.

  The soot reduction control unit 33 suppresses soot accumulation in the exhaust pipe 14 of the internal combustion engine 2 based on the excess air ratio λ of the internal combustion engine 2 when the acceleration operation of the vehicle 1 is performed. Execute. Specifically, the soot reduction control unit 33 includes a reference excess air ratio Λ that is set in advance and is stored in the ROM of the ECU 31 as a reference for determining whether to execute the soot reduction control, and an excess air ratio calculation unit 35. The calculated excess air ratio λ is compared, and when the excess air ratio λ is less than the reference excess air ratio Λ, that is, when λ <Λ, the soot reduction control is executed.

  Here, the excess air ratio λ is calculated by an excess air ratio calculation unit 35 described later, and is represented by a value obtained by dividing the amount of air used for actual combustion by the amount of air of the stoichiometric air-fuel ratio. Note that the theoretical air-fuel ratio is λ = 1. The air amount may be an intake air amount (g / sec) which is a fresh air amount per unit time taken into the cylinder of the internal combustion engine 2, or a cylinder intake air which is a fresh air amount taken into the cylinder of the internal combustion engine 2. It may be an amount (g / TDC). g / TDC represents the amount of air per 1 TDC period, that is, the time required for the crankshaft of the internal combustion engine 2 to rotate 180 degrees. The amount of air is detected by the intake air flow rate sensor 41.

The soot reduction control unit 33 reduces the fuel injection amount injected from the injector 13 by a predetermined amount F when λ <Λ. The fuel injection amount is represented by the fuel injection amount (g) per injection injected from the injector 13 and the number of injections per unit time.
The soot reduction control unit 33 reduces the fuel injection amount by a predetermined amount F (g), thereby restricting the fuel rich state where the fuel is excessive and improving the fuel in the combustion chamber (not shown) of the internal combustion engine 2. The generation of soot is suppressed by promoting proper combustion.

  The acceleration performance decrease detection unit 34 detects execution of the soot reduction control by the soot reduction control unit 33 as a decrease in acceleration performance, and outputs detection information to the air conditioning control unit 32. That is, when the soot reduction control is performed by the soot reduction control unit 33, the fuel injection amount is reduced by the predetermined amount F, so that the output from the internal combustion engine 2 is also reduced, and the acceleration performance of the vehicle 1 is reduced. Become.

  Here, the acceleration performance is, for example, a time (sec) until the vehicle 1 reaches a specific distance (m) and a vehicle speed (km / h) from a stopped state, or reaches a specific vehicle speed from constant speed travel. Indicates the length of time required for The acceleration performance is measured by measuring the vehicle speed, distance, and time on a flat road, and is represented by a distance (m) from the acceleration measurement start point and a required time (sec) with respect to the vehicle speed.

  The excess air ratio calculation unit 35 calculates the amount of air used for actual combustion from the intake air flow rate detected and output by the intake air flow rate sensor 41, and divides the calculated air amount by the air amount of the theoretical air-fuel ratio. Thus, the excess air ratio λ is calculated. Information on the calculated excess air ratio λ is output to the soot reduction control unit 33.

  The driving state detection unit 36 detects whether or not the vehicle 1 has started acceleration, and outputs detection information to the air conditioning control unit 32. Whether or not the vehicle 1 has started acceleration is detected based on wheel speed information output from the wheel speed sensor 42 and accelerator opening information output from the accelerator opening sensor 43.

  The reference excess air ratio Λ, the predetermined amount F of fuel injection amount, and the predetermined time T vary depending on the vehicle type and the specifications of the internal combustion engine, but are appropriate values set based on experience values and data, and are appropriately selected.

  Next, the flow of air conditioning control in the ECU 31 of the present embodiment will be described with reference to the flowchart shown in FIG. The air conditioning control described below is repeatedly executed at predetermined time intervals when the ECU 31 detects that an ignition switch (not shown) is turned on.

  First, the ECU 31 determines whether or not the acceleration of the vehicle 1 has been started by the driving state detection unit 36 (step S1). If it is determined that acceleration has not started, step S1 is repeatedly executed at predetermined time intervals until acceleration is started.

  When the ECU 31 determines that the acceleration of the vehicle 1 is started by the driving state detector 36, the ECU 31 determines whether or not the air conditioner 3 is in the ON state by the air conditioner controller 32 (step S2). Whether or not the air conditioner 3 is in an ON state depends on whether or not the condition that the clutch 22 of the air conditioner 3 is in a transmission state and that an air conditioner switch (not shown) of the air conditioner 3 is in an ON state is satisfied. It is judged by.

  When the ECU 31 determines in step S2 that the clutch 22 of the air conditioner 3 is in a non-transmitting state, that is, the air conditioner is in an OFF state, the ECU 31 returns the process to step S1. On the other hand, when it is determined that the air conditioner is in the ON state, the excess air ratio λ is calculated by the excess air ratio calculation unit 35 (step S3).

  Subsequently, the ECU 31 compares the excess air ratio λ calculated in step S3 by the soot reduction control unit 33 with the reference excess air ratio Λ stored in the ROM of the ECU 31, and the excess air ratio λ is determined to be the excess reference air. It is determined whether or not the ratio Λ is smaller, that is, whether or not λ <Λ is satisfied. That is, the wrinkle reduction control unit 33 determines whether or not the wrinkle reduction control can be executed (step S4).

  When the ECU 31 determines in step S4 that the heel reduction control unit 33 satisfies λ <Λ and the heel reduction control can be executed, the heel reduction control unit 33 executes the heel reduction control. (Step S5). Subsequently, the ECU 31 causes the air conditioning control unit 32 to switch the clutch 22 of the air conditioner 3 to the non-transmission state, thereby interrupting the power transmitted from the internal combustion engine 2 to the compressor 21. As a result, the compressor 21 stops and the air conditioner 3 is turned off (step S6).

  At this time, the ECU 31 measures the stop time from the start of the stop of the compressor 21 with a timer (not shown) by the air conditioning control unit 32, and the measured stop time t of the compressor 21 is set in advance and stored in the ROM. It is determined whether or not T is exceeded, that is, whether or not t> T is satisfied (step S7).

  Next, when it is determined in step S7 that t> T is satisfied, the ECU 31 switches the clutch 22 of the air conditioner 3 from the non-transmission state to the transmission state by the air conditioning control unit 32 to compress the power from the internal combustion engine 2. 21. Thereby, the compressor 21 is driven, the air conditioner 3 is turned on (step S8), and the air conditioning control is finished.

  On the other hand, when it is determined in step S4 that execution of the soot reduction control is impossible, the ECU 31 advances the control to step S8, causes the air conditioning control unit 32 to drive the compressor 21, and ends the air conditioning control. When the ECU 31 determines that the execution of the soot reduction control in step S4 is not possible for the first time, the ECU 31 ends the air conditioning control without passing through step S8 because the compressor 21 has not stopped.

  If the air conditioning control unit 32 determines in step S7 that t> T is not satisfied, the ECU 31 returns the air conditioning control to step S3. As a result, the ECU 31 determines that t> T as a result of determination in the air conditioning control unit 32, and that λ exceeds Λ as a result of determination in the soot reduction control unit 33 while the compressor 21 is stopped, that is, soot reduction control. If any of the conditions that the execution of is not possible is satisfied, the compressor 21 is driven to end the air conditioning control.

  Next, the flow of air conditioning control in the ECU 31 of the present embodiment will be described with reference to the time chart shown in FIG. The horizontal axis of FIG. 3 shows the passage of time, and the vertical axis shows the state of each control element.

  First, at time t1, it is detected that the clutch 22 of the air conditioner 3 is in a transmission state and an air conditioner switch (not shown) of the air conditioner 3 is in an ON state. Then, at time t1, the accelerator pedal 5 is depressed and the accelerator position information output from the accelerator position sensor 43 and the wheel speed information output from the wheel speed sensor 42 are used to detect the acceleration of the vehicle 1 by the driving state detector 36. Start is detected.

  When the start of acceleration of the vehicle 1 is detected, the fuel injection amount injected from the injector 13 increases and the excess air ratio λ decreases. At time t2, the excess air ratio λ becomes less than the reference excess air ratio Λ. When the excess air ratio λ becomes less than the reference excess air ratio Λ, the soot reduction control unit 33 sets the fuel injection amount by a predetermined amount F so as to suppress soot accumulation in the exhaust pipe 14 of the internal combustion engine 2. The wrinkle reduction control to reduce is executed.

  By executing the soot reduction control, the acceleration performance of the vehicle 1 is reduced due to the decrease in the fuel injection amount. Therefore, the driving of the compressor 21 is stopped by the air conditioning control unit 32 so as to suppress the reduction in the acceleration performance. Simultaneously with the stop of the drive of the compressor 21, the stop time t of the compressor 21 is measured by a timer.

  At time t3 after the driving of the compressor 21 is stopped, for example, the supercharging pressure supplied from the supercharger is sufficiently increased with the acceleration of the vehicle 1, and the excess air ratio λ is set as a reference by increasing the intake air amount. When the excess air ratio Λ or more is reached, the soot reduction control unit 33 ends the soot reduction control and the air conditioning control unit 32 drives the compressor 21 again. When the compressor 21 is driven again, the measurement of the stop time t of the compressor 21 by the timer ends.

  After that, at time t4, the accelerator pedal 5 is depressed again, and the start of acceleration of the vehicle 1 is detected by the driving state detection unit 36 based on the accelerator opening information and the wheel speed information. When the start of acceleration is detected, the fuel injection amount injected from the injector 13 increases again, and the excess air ratio λ decreases. At time t5, the excess air ratio λ becomes less than the reference excess air ratio Λ. When the excess air ratio λ becomes less than the reference excess air ratio Λ, the soot reduction control unit 33 executes the soot reduction control for reducing the fuel injection amount by a predetermined amount F again.

  By executing the soot reduction control, the acceleration performance of the vehicle 1 is reduced due to a decrease in the fuel injection amount. Therefore, the driving of the compressor 21 is stopped again by the air conditioning control unit 32 so as to suppress the reduction in the acceleration performance. Simultaneously with the stop of driving of the compressor 21, the stop time t of the compressor 21 is measured again by the timer.

Thereafter, even when the excess air ratio λ is maintained to be less than the reference excess air ratio Λ at time t6, the compressor 21 is driven again when the stop time t of the compressor 21 exceeds the predetermined time T, The measurement of the stop time t of the compressor 21 by the timer ends.
Further, after the elapse of time t6, when the excess air ratio λ becomes equal to or greater than the reference excess air ratio Λ, the soot reduction control unit 33 ends the soot reduction control.

  Since the air conditioning control device 4 according to the present embodiment is configured as described above, the following effects are obtained.

  The air conditioning control device 4 according to the present embodiment includes an air conditioning control unit 32 and an acceleration performance decrease detection unit 34, and the acceleration performance decrease detection unit 34 decreases the acceleration performance of the vehicle 1 based on the operating state of the internal combustion engine 2. The air conditioning control unit 32 is configured to stop the driving of the compressor 21 on the condition that the acceleration performance detected by the acceleration performance decrease detection unit 34 is deteriorated.

  Thereby, the air-conditioning control apparatus 4 which concerns on this embodiment can implement | achieve suppression of the fall of air-conditioning performance, suppressing the fall of the acceleration performance of the vehicle 1. FIG. That is, the air-conditioning control device 4 according to the present embodiment stops the driving of the compressor 21 only when the acceleration performance of the vehicle 1 is reduced, thereby turning off the air-conditioning device 3 to accelerate the internal combustion engine 1. By eliminating the load on the engine 2, the deterioration of the acceleration performance is suppressed. On the other hand, except when it is detected by the acceleration performance decrease detection unit 34 that the acceleration performance is deteriorated, the driving of the compressor 21 is not stopped and the ON state of the air conditioner 3 is maintained. It is suppressed.

In addition, the air conditioning control device 4 according to the present embodiment includes the soot reduction control unit 33, and the acceleration performance decrease detection unit 34 detects execution of soot reduction control by the soot reduction control unit 33 as a decrease in the acceleration performance of the vehicle 1. It is configured to
Thereby, the air-conditioning control apparatus 4 which concerns on this embodiment can implement | achieve suppression of the fall of air-conditioning performance, suppressing the fall of the acceleration performance of the vehicle 1 more reliably. That is, the air conditioning control device 4 according to the present embodiment actually reduces the acceleration performance of the vehicle 1 in consideration of the decrease in the fuel injection amount when the soot reduction control by the soot reduction control unit 33 is performed. Since the execution of the reduction control is detected, a decrease in the acceleration performance of the vehicle 1 can be more reliably suppressed. Except when the soot reduction control is performed by the soot reduction control unit 33, the driving of the compressor 21 is not stopped and the ON state of the air conditioner 3 is maintained, so that a decrease in air conditioning performance is suppressed. As a result, it is possible to more reliably suppress a decrease in air conditioning performance while suppressing a decrease in acceleration performance of the vehicle 1 more reliably.

  While embodiments of the invention have been disclosed, it will be apparent to those skilled in the art that changes may be made without departing from the scope of the invention. All such modifications and equivalents are intended to be included in the following claims.

DESCRIPTION OF SYMBOLS 1 Vehicle 2 Internal combustion engine 3 Air conditioning apparatus 4 Air conditioning control apparatus 5 Accelerator pedal 11 Engine main body 12 Intake pipe 13 Injector 14 Exhaust pipe 21 Compressor 31 ECU
32 Air-conditioning control unit 33 Haze reduction control unit 34 Acceleration performance drop detection unit 35 Air excess rate calculation unit 36 Operating state detection unit 41 Intake air flow rate sensor 42 Wheel speed sensor 43 Accelerator opening sensor F Predetermined amount of fuel injection t Stop time T Predetermined time λ Excess air ratio Λ Reference excess air ratio

Claims (2)

In an air conditioning control device that controls an air conditioning device having a compressor driven by the power of an internal combustion engine according to the acceleration operation of the host vehicle,
An acceleration performance decrease detection unit that detects whether or not the acceleration performance of the host vehicle is deteriorated based on the operating state of the internal combustion engine;
An air conditioning control unit that stops driving of the compressor, on condition that the acceleration performance detected by the acceleration performance decrease detection unit is degraded;
An air conditioning control device characterized by comprising: A soot reduction control unit that performs soot reduction control that suppresses soot accumulation in the exhaust pipe of the internal combustion engine based on the excess air ratio of the internal combustion engine when the acceleration operation is performed;
The air conditioning control device according to claim 1, wherein the acceleration performance decrease detection unit detects execution of the wrinkle reduction control by the wrinkle reduction control unit as a decrease in the acceleration performance.

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