JP6091300B2 - Vehicle control device - Google Patents

Description

  The present invention relates to a vehicle control device equipped with an internal combustion engine that includes a rotation speed sensor that detects the rotation speed, and an air conditioner that includes a refrigerant compression compressor that operates by receiving a rotational driving force output from the internal combustion engine.

  Conventionally, in order to improve the fuel consumption of a vehicle, etc., an idle stop is performed when a predetermined idle stop condition is satisfied, and after the idle stop condition is satisfied, Control to restart has been widely performed.

  Here, various controls for stopping the piston at a desired position or for quickly stopping the piston have been considered in order to smoothly restart the internal combustion engine after performing the idle stop. As one of such controls, there is one that performs control to increase the rotational load of the internal combustion engine by an air conditioner or the like in order to reduce the swingback behavior immediately before the internal combustion engine stops (for example, see Patent Document 1). reference).

  However, when the control for increasing the load of the air conditioner is performed in order to reduce the swing-back behavior immediately before the internal combustion engine stops, the following problems may occur. In other words, the internal combustion engine may perform reverse rotation during the swing-back behavior immediately before the internal combustion engine stops. Thus, the refrigerant compression compressor of an air conditioner normally performs only rotation in one direction, and when a reverse rotational driving force is input from the crankshaft, a large load is applied to the refrigerant compression compressor. In some cases, there may be a problem that a failure may occur.

JP 2006-242082 A (refer to paragraph 0069 and paragraph 0070 in particular)

  The present invention focuses on the above points, and an object of the present invention is to perform control to stop the piston so as to smoothly restart the internal combustion engine after performing idle stop without causing failure of the air conditioner. .

  In order to solve the above problems, a vehicle control apparatus according to the present invention has a configuration as described below. That is, a vehicle control apparatus according to the present invention is an internal combustion engine that includes a rotation speed sensor that detects a rotation speed, and is used for refrigerant compression that is operated by receiving a rotational driving force output from the internal combustion engine and can change a load on the internal combustion engine. A control device that controls a vehicle equipped with an air conditioner including a compressor, and performs idle stop control when a predetermined idle stop condition is satisfied, and the crankshaft immediately before the internal combustion engine is stopped during the idle stop control. When the swing-back behavior is observed, control is performed to increase the load on the air conditioner during forward rotation of the crankshaft and to reduce the load on the air conditioner during reverse rotation of the crankshaft compared to when the crankshaft rotates forward. Do.

  If such control is performed, when the crankshaft swing-back behavior is observed immediately before the internal combustion engine is stopped, the load on the air conditioner is increased during normal rotation of the crankshaft, thereby smoothly restarting the internal combustion engine. The piston can be stopped at a desired position or can be quickly stopped. On the other hand, when the crankshaft rotates in the reverse direction, the load on the air conditioner is reduced compared to when the crankshaft rotates in the forward direction, thereby preventing a large reverse rotational driving force from being input to the compressor of the air conditioner. Therefore, failure of the air conditioner can be prevented.

  According to the present invention, it is possible to perform control to stop the piston so as to smoothly restart the internal combustion engine after performing idle stop without causing failure of the air conditioner.

1 is a schematic diagram showing the configuration of an internal combustion engine according to an embodiment of the present invention. Schematic which shows the structure of the air conditioner which concerns on the embodiment. The flowchart which shows the procedure of the control which the control apparatus of the embodiment performs. The time chart which shows the content of the control which the control apparatus of the embodiment performs.

  An embodiment of the present invention will be described with reference to the drawings.

  FIG. 1 shows an outline of an internal combustion engine for a vehicle in the present embodiment. The internal combustion engine is, for example, a spark ignition type four-stroke engine, and includes a plurality of cylinders 1 (one of which is shown in FIG. 1). In the vicinity of the intake port of each cylinder 1, an injector 11 for injecting fuel is provided. A spark plug 12 is attached to the ceiling of the combustion chamber of each cylinder 1. The spark plug 12 receives spark voltage generated by the ignition coil and causes spark discharge between the center electrode and the ground electrode. The ignition coil is integrally incorporated in a coil case together with an igniter that is a semiconductor switching element.

  The intake passage 3 for supplying intake air takes in air from the outside and guides it to the intake port of each cylinder 1. On the intake passage 3, an air cleaner 31, an electronic throttle valve 32, a surge tank 33, and an intake manifold 34 are arranged in this order from the upstream.

  The exhaust passage 4 for discharging the exhaust guides the exhaust generated as a result of burning the fuel in the cylinder 1 from the exhaust port of each cylinder 1 to the outside. An exhaust manifold 42 and an exhaust purification three-way catalyst 41 are disposed on the exhaust passage 4.

  In FIG. 2, the structure of the air conditioner 5 which is an air conditioner which air-conditions the vehicle interior is shown. The air conditioner 5 includes a compressor 51 that compresses the refrigerant, a capacitor 52 that radiates and liquefies the compressed refrigerant, a capacitor fan 53 that forcibly cools the capacitor 52, and a gaseous refrigerant that has not been liquefied. The refrigerant 54 is separated from the liquefied refrigerant, the expansion valve 55 for ejecting the liquefied refrigerant, the evaporator 56 for receiving the ejected vaporized refrigerant and exchanging heat with the air in the room, and obtaining cold heat from the refrigerant. A blower fan 57 for sending air into the room (heat is removed) is connected to the compressor 51, the condenser 52, the receiver 54, the expansion valve 55, and the evaporator 56 through a refrigerant flow path that loops.

  The compressor 51 rotates upon receiving a driving force transmitted from the crankshaft of the internal combustion engine. The compressor 51 is a conventionally known variable capacity compressor. More specifically, in response to a load signal l from ECU0, which will be described later, the solenoid is controlled by changing the current value of the energization current to the internal solenoid, and the suction pressure of the refrigerant is changed by changing the piston stroke. To do. Of course, instead of changing the current value of the energization current to the solenoid, a variable capacity compressor that controls the solenoid by changing the duty ratio may be adopted. Between the compressor 51 and the crankshaft, there is a magnet clutch 58 capable of switching between connection and disconnection. The magnet clutch 58 is connected when an internal relay switch (not shown) receives an energization signal m from the ECU 0 described later.

  The condenser 52 is disposed at a portion where the traveling wind hits in the engine room of the vehicle, and is cooled by the traveling wind blown into the engine room during traveling of the vehicle regardless of whether the condenser fan 53 is rotated. Behind the condenser 52 is a radiator 7 for radiating the cooling water of the internal combustion engine. The radiator 7 is also cooled by the traveling wind.

The condenser fan 53 also serves as a radiator fan for forcibly cooling the radiator 7 with air. The condenser fan 53 is located behind the radiator 7 and cools both the condenser 52 and the radiator 7 by sucking air from the front and discharging it to the rear.

  An ECU (Electronic Control Unit) 0 that is a control device of the present embodiment is a microcomputer system having a processor, a memory, an input interface, an output interface, and the like.

  The input interface includes a vehicle speed signal a output from a vehicle speed sensor that detects the actual vehicle speed of the vehicle, a crank angle signal b output from an engine rotation sensor that detects the rotation angle and engine speed of the crankshaft, and depression of an accelerator pedal. The accelerator opening signal c output from a sensor that detects the amount or the opening of the throttle valve 32 as an accelerator opening (so-called required load), the intake air temperature and the intake pressure in the intake passage 3 (particularly, the surge tank 33). The intake air temperature / intake pressure signal d output from the temperature / pressure sensor to be detected, the coolant temperature signal e output from the water temperature sensor to detect the coolant temperature of the internal combustion engine, and the capacitor 52 of the air conditioner 5 flow out (relatively). The refrigerant pressure signal f output from the refrigerant pressure sensor for detecting the pressure of the refrigerant (high pressure), the evaporator of the air conditioner 5 Output from the refrigerant pressure signal g output from the refrigerant pressure sensor that detects the pressure of the refrigerant flowing out of the data 56 (relatively low pressure), and from the sensor that detects the temperature of the evaporator 56 (or air in the vicinity of the evaporator 56). The evaporator temperature signal h, the outside air temperature signal p output from the temperature sensor for detecting the outside air temperature, the room temperature signal q output from the temperature sensor for detecting the room temperature of the vehicle, and the like are input.

  From the output interface, an ignition signal i for the igniter of the spark plug 12, a fuel injection signal j for the injector 11, an opening operation signal k for the throttle valve 32, a load signal l for the compressor 51, a magnet clutch An energization signal m or the like is output to 58 relay switches.

  The processor of the ECU 0 interprets and executes a program stored in the memory in advance, calculates operation parameters, and controls the operation of the internal combustion engine. The ECU 0 obtains various information a, b, c, d, e, f, g, h, p, q necessary for operation control of the internal combustion engine through the input interface, and knows the engine speed, and the cylinder 1 Estimate the amount of intake air to be filled. Based on the engine speed, the intake air amount, and the like, various operating parameters such as required fuel injection amount, fuel injection timing (including the number of times of fuel injection for one combustion), fuel injection pressure, and ignition timing are determined. As the operation parameter determination method itself, a known method can be adopted. The ECU 0 applies various control signals i, j, k, l, and m via the output interface.

  Further, the ECU 0 of the present embodiment executes an idle stop that stops the idle rotation of the internal combustion engine when the vehicle stops due to a signal waiting or the like. The ECU 0 is satisfied by all the conditions such as the vehicle speed is a predetermined value, for example, 13 km / h or less, the brake pedal is depressed, the cooling water temperature and the battery voltage are sufficiently high, and the brake booster negative pressure is sufficiently secured. Therefore, it is determined that the idle stop condition is satisfied.

  When a predetermined idle stop end condition is satisfied after the idle stop condition is satisfied, the internal combustion engine is restarted. The ECU 0 is one in which the driver takes his foot off the brake pedal, the brake pedal is depressed more strongly, the accelerator pedal is depressed, a predetermined time (for example, 3 minutes) has elapsed in the idle stop state, etc. In any case, it is determined that the idle stop end condition is satisfied.

  Thus, in the present embodiment, the processor of the ECU 0 executes an air conditioner load control program as described below in order to smoothly restart the internal combustion engine after performing the idle stop. That is, when the crankshaft swing-back behavior is observed immediately before the internal combustion engine is stopped during the idle stop control, the load of the air conditioner is increased during the forward rotation of the crankshaft, and the forward rotation of the crankshaft is performed during the reverse rotation of the crankshaft. Control is performed to reduce the load on the air conditioner compared to when rotating.

  More specifically, when the idling stop condition is satisfied, the energization signal m is output to the relay switch of the magnet clutch 58 between the air conditioner 5 and the crankshaft, and the air conditioner 5 and the crankshaft are connected. Increase the load by connecting. At that time, a load signal l for making the load by the air conditioner 5 the maximum load is output to the compressor 51. On the other hand, during the reverse rotation of the crankshaft, a load signal l indicating a load smaller than the maximum load is output to the compressor 51 in order to reduce the load applied by the air conditioner 5 more than during the forward rotation of the crankshaft.

  Hereinafter, a control procedure performed by the processor executing this lock-up control program will be described below with reference to FIG. 3 which is a flowchart.

After the idle stop condition is satisfied, when the rotational speed Ne falls below the predetermined rotational speed Ne ₀ (step S1), it is considered that the crankshaft has started to swing back, and the air conditioner 5 and the crankshaft An energization signal m is output to the relay switch of the magnet clutch 58 between the air conditioner 5 and the crankshaft (step S2). At that time, a load signal l is output to the compressor 51 so that the load by the air conditioner 5 is the maximum load. Thereafter, when it is detected that the crankshaft is rotating in reverse (step S3), a load signal l is output to the compressor 51 so that the load by the air conditioner 5 is lower than the maximum load. (Step S4). On the other hand, when the reverse rotation of the crankshaft is not detected, that is, when the forward rotation of the crankshaft is detected (step S3), the load on the air conditioner 5 is continuously maximized. A load signal l is output to the compressor 51 to make a load (step S5). Then, when the crankshaft is stopped (step S6), this control is finished. If the crankshaft is still rotating, the process returns to the control in step S3, that is, the control for determining whether or not the crankshaft is rotating in reverse.

That is, as shown in FIG. 4, after the idle stop condition is established (time T ₁ ), the air conditioner 5 and the crankshaft are connected when the crankshaft starts to swing back (time T ₂ ). (In FIG. 4, the A / C flag is indicated as ON). At the time T ₂ , the internal combustion engine is rotating in the positive direction, so the load by the air conditioner 5 (shown as A / C load in FIG. 4) is the maximum load. During the period from time T ₂ to time T _{3 in} the figure, the internal combustion engine is rotating in the forward direction, so that the load by the air conditioner 5 is kept at the maximum load. On the other hand, the period from the time T ₃ to time T ₄ in the figure, since the internal combustion engine is rotating in the reverse direction, the load due to the air conditioner 5 is lower than the maximum load. Also during the period after time T _{4, the} load by the air conditioner 5 is kept at the maximum load during the period in which the internal combustion engine is rotating in the forward direction, and the air conditioner 5 is in the period during which the internal combustion engine is rotating in the reverse direction. The load is kept below the maximum load.

  By performing such control, when the swing back behavior of the crankshaft is observed immediately before the internal combustion engine is stopped, the air conditioner 5 and the crankshaft are connected during the forward rotation of the crankshaft. By setting the load to the maximum load, the piston can be stopped to smoothly restart the internal combustion engine. On the other hand, a large rotational driving force in the reverse direction is input to the compressor 51 of the air conditioner 5 by reducing the load of the air conditioner during reverse rotation of the crankshaft compared to when the crankshaft rotates forward. It is possible to prevent the failure of the air conditioner 5.

  The present invention is not limited to the embodiment described above.

  For example, in a vehicle equipped with an air conditioner equipped with a fixed displacement compressor instead of a variable displacement compressor, when the swing back behavior of the crankshaft is observed immediately before stopping the internal combustion engine during idle stop control, the compressor and the crankshaft By controlling the ON / OFF duty ratio of the magnet clutch during the period, the load of the air conditioner may be changed between when the crankshaft is rotating forward and when it is rotating backward. Specifically, when the swing back behavior of the crankshaft is observed immediately before the internal combustion engine is stopped during idle stop control, the duty ratio of the magnet clutch is set to 100% during the forward rotation of the crankshaft, and the crankshaft is rotated in reverse. Sometimes the duty ratio of the magnet clutch may be set to a value smaller than 100%.

  In addition, various changes may be made without departing from the spirit of the present invention.

0 ... Control unit (ECU)
5 ... Air conditioner (air conditioner)
51 ... Compressor for refrigerant compression b ... Crank angle signal

Claims (1)

A vehicle equipped with an internal combustion engine having a rotation speed sensor for detecting the rotation speed, and an air conditioner having a refrigerant compression compressor that operates by receiving a rotational driving force output from the internal combustion engine and can change a load on the internal combustion engine. A control device for controlling,
When a predetermined idle stop condition is satisfied, idle stop control is performed, and when the crankshaft swinging behavior is observed immediately before the internal combustion engine is stopped during the idle stop control, the air conditioner is operated during the forward rotation of the crankshaft. The vehicle control device is characterized in that control is performed to reduce the load of the air conditioner when the crankshaft rotates reversely compared to when the crankshaft rotates forward.

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