JP2016125445A - Rotation stop position controlling apparatus of engine - Google Patents

Abstract

PROBLEM TO BE SOLVED: To adjust pressure in each cylinder in an advantageous state to restart an engine, respectively, when stopping the engine.SOLUTION: An electronic throttle device 7 is subjected to valve opening control to adjust an intake air amount supplied into each cylinder 2. An intake suppression valve 36 is subjected to valve closing control to suppress filling of the intake air into one cylinder 2. A rotation speed sensor 45 detects a crank angle and a rotation speed of a crankshaft 3. An ECU 50 controls each injector 32 such that a fuel cut in an intake stroke of each cylinder 2 is to be started from a specific cylinder 2 on the basis of the detected crank angle to stop the crankshaft 3 at a predetermined crank angle. Further, the ECU controls valve opening of the electronic throttle device 7 to fill each cylinder 2 with the intake air, and after the valve opening control, controls valve closing of the intake suppression valve 36.SELECTED DRAWING: Figure 1

Description

  The present invention relates to an engine rotation stop position control device configured to control a rotation stop position of a rotation shaft of an engine when the engine is stopped.

  Conventionally, as a technology in this type of field, for example, an engine starter described in Patent Document 1 below is known. This apparatus is employed in an idle stop system that automatically stops and automatically starts an engine having a plurality of cylinders. Here, in order to improve the restartability of the engine, when the engine automatically stops (idle stop) during idle operation, the engine rotation stop position (stop crank angle) is controlled to a crank angle range suitable for restart. It is like that. That is, when the engine is stopped, fuel is injected into the cylinder in the expansion stroke and ignited and burned to restart the engine with the power of the engine itself without borrowing the power of the starter motor. It is like that. Specifically, the engine rotation speed when each cylinder passes the compression top dead center in the process in which the engine rotation speed decreases after starting the fuel supply stop (fuel cut) to the engine (top dead center rotation speed) Is detected by a rotational speed sensor, and the opening degree of the throttle valve is electrically controlled so that the top dead center rotational speed is within a predetermined rotational speed range correlated with the piston position after the engine is stopped. Yes. As a result, the crankshaft is stopped at a specific crank angle.

JP 2005-155548 A

  By the way, in order to idle stop the engine during idle operation, it is necessary to make each of the cylinders of the engine have a pressure state that is advantageous for restarting the engine. That is, among the cylinders, it is necessary to set a positive pressure or atmospheric pressure in the cylinder in the expansion stroke, and a negative pressure with less compression in the cylinder in the compression stroke. However, in the apparatus described in Patent Document 1, the pressure state in each cylinder is only adjusted by controlling the opening degree of the throttle valve, and the pressure in each cylinder is advantageous for restarting the engine. It was not possible to adjust to the condition.

  The present invention has been made in view of the above circumstances, and an object of the present invention is to make it possible to adjust each of the cylinders to a pressure state advantageous for restarting the engine when the engine is stopped. An object of the present invention is to provide a rotation stop position control device.

  In order to achieve the above object, an invention according to claim 1 is an engine rotation stop position control device for controlling an engine rotation shaft to stop at a predetermined rotation position, the engine comprising a plurality of cylinders. The reciprocating engine includes: a reciprocating engine configured to rotate the rotation shaft by burning the fuel supplied by the fuel supply means in each cylinder; and the intake air for adjusting the intake air amount supplied to each cylinder Based on the rotation position detected by the rotation detection means for stopping the rotation shaft at a predetermined rotation position, each cylinder, and a rotation detection means for detecting the rotation position and rotation speed of the rotation shaft The fuel supply means is controlled so as to start stopping the fuel supply from a specific cylinder, and the control means for controlling the opening of the intake air amount adjusting valve to fill each cylinder with intake air The rotation stop position control device further includes an intake air suppression valve for suppressing charging of intake air into at least one of the plurality of cylinders, and the control means stops the rotation shaft at a predetermined rotation position. The intent is to control the closing of the intake suppression valve after starting the stop of fuel supply and controlling the opening of the intake air amount adjusting valve.

  According to the configuration of the invention described above, when the engine is stopped, the control means stops the fuel supply to each cylinder based on the rotation position detected by the rotation detection means in order to stop the rotation shaft at a predetermined rotation position. The fuel supply means is controlled to start from a specific cylinder, and the intake air amount adjustment valve is controlled to open in order to fill each cylinder with intake air. Here, when the rotating shaft is stopped at a predetermined rotational position, the control means starts stopping the fuel supply, controls the opening of the intake air amount adjusting valve, and then controls the closing of the intake air suppression valve. Therefore, a negative pressure is applied to the cylinder in which the charging of the intake air is suppressed by closing the intake air suppression valve, and the intake air is charged according to the operation stroke in the other cylinders.

  In order to achieve the above object, according to a second aspect of the present invention, in the first aspect of the present invention, the control means controls the rotation position detected by the rotation detection means when the intake suppression valve is closed. The purpose is to correct the deviation.

  According to the configuration of the invention described above, in addition to the operation of the invention described in claim 1, by closing the intake air suppression valve, a load is applied to the rotary shaft, and the rotational position of the rotary shaft may shift. Here, when the intake control valve is controlled to be closed, the deviation of the rotational position detected by the rotation detecting means is corrected and reduced.

  In order to achieve the above object, the invention according to claim 3 is the invention according to claim 2, wherein the control means corrects the rotational position deviation more greatly as the opening of the intake suppression valve becomes smaller. And

  According to the configuration of the above invention, in addition to the operation of the invention according to claim 2, the load applied to the rotating shaft increases as the opening degree of the intake suppression valve decreases, and the rotational position shift detected by the rotation detecting means increases. Becomes larger. Here, the smaller the opening of the intake suppression valve is, the more the rotational position shift is corrected. Therefore, the rotational position shift is accurately corrected.

  In order to achieve the above object, a fourth aspect of the present invention is the rotation according to any one of the first to third aspects, wherein the rotational speed of the rotary shaft is adjusted by applying a load to the rotary shaft. The control means further includes an adjusting means, and the control means sets the top dead center rotational speed within the predetermined range when the top dead center rotational speed detected by the rotation detecting means when each cylinder is at the top dead center is not within the predetermined range. The purpose of this is to control the rotation adjusting means to make adjustments.

  According to the configuration of the invention, in addition to the operation of the invention according to any one of claims 1 to 3, a load is applied to the rotating shaft, and the top dead center rotation speed causes the rotation of the rotating shaft to stop. It is adjusted within a predetermined range suitable for.

  In order to achieve the above object, according to a fifth aspect of the present invention, in the fourth aspect of the present invention, the control means is configured such that the top dead center rotational speed detected by the rotation detecting means is not more than a predetermined value within a predetermined range. In this case, the purpose is to fix or stop the supply of the load to the rotating shaft by the rotation adjusting means.

  According to the configuration of the above invention, in addition to the operation of the invention according to claim 4, the supply of the load to the rotating shaft is fixed or stopped, and the top dead center rotation speed causes the rotation of the rotating shaft to stop. It is fixed at a rotation speed suitable for.

  According to the first aspect of the present invention, when the engine is stopped, each of the cylinders can be adjusted to a pressure state advantageous for restarting the engine.

  According to the invention described in claim 2, in addition to the effect of the invention described in claim 1, when the engine is stopped, the rotating shaft can be brought close to a predetermined rotational position and stopped.

  According to the invention described in claim 3, in addition to the effect of the invention described in claim 2, when the engine stops, the rotating shaft can be accurately stopped at a predetermined rotational position.

  According to the invention described in claim 4, in addition to the effect of the invention described in any one of claims 1 to 3, when the engine is stopped, the rotation shaft can be accurately stopped at a predetermined rotation position. .

  According to the invention described in claim 5, in addition to the effect of the invention described in claim 4, even if the load applied to the rotating shaft fluctuates in the middle, the rotating shaft is It is possible to stop at a predetermined rotational position more accurately.

1 is a schematic configuration diagram illustrating an engine system according to an embodiment. The schematic which shows the structure of a cylinder concerning one Embodiment. 1 is a schematic view of an engine system showing an arrangement of an electronic throttle device and an intake air suppression valve in an intake passage according to one embodiment. The front view which concerns on one Embodiment and shows the relationship between arrangement | positioning of a rotational speed sensor and a timing rotor. The flowchart which shows the content of engine rotation stop position control concerning one Embodiment. The map referred to in order to obtain | require the deviation | shift amount of the total crank angle TCA according to one Embodiment according to the closing amount of an intake control valve. The behavior of (a) engine speed NE, (b) total crank angle TCA, (c) fuel cut flag XFC, (d) throttle valve opening flag XSO, and (e) intake air suppression flag XRC, according to one embodiment. Time chart.

  DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiments of an engine rotation stop position control device according to the present invention will be described below in detail with reference to the drawings.

  FIG. 1 is a schematic configuration diagram showing an engine system in this embodiment. In this embodiment, an engine 1 mounted on an automobile is a four-cycle reciprocating engine, and includes four cylinders 2 and a crankshaft 3 that is a rotating shaft of the present invention. The engine 1 is provided with an intake passage 4 and an exhaust passage 5. An air cleaner 6, an electronic throttle device 7, and a surge tank 8 are provided in the intake passage 4 from the upstream side. The electronic throttle device 7 includes a throttle valve 9 that is opened and closed by a motor 31 and a throttle sensor 41 for detecting the opening degree (throttle opening degree) TA of the throttle valve 9. Equivalent to. The exhaust passage 5 is provided with a catalytic converter 10 for purifying exhaust gas.

  The engine 1 includes a cylinder block 11 and a cylinder head 12. In the cylinder block 11, a piston 13 is provided for each cylinder 2. Each piston 13 is connected to the crankshaft 3 via a connecting rod 14. Each cylinder 2 includes a combustion chamber 15. That is, in each cylinder 2, the combustion chamber 15 is formed between the piston 13 and the cylinder head 12. An intake port 16 and an exhaust port 17 communicating with each combustion chamber 15 are formed in the cylinder head 12. Each intake port 16 communicates with the intake passage 4. Each exhaust port 17 communicates with the exhaust passage 5. Each intake port 16 is provided with an intake valve 18, and each exhaust port 17 is provided with an exhaust valve 19. Each intake valve 18 and each exhaust valve 19 are linked to the rotation of the crankshaft 3, that is, linked to the vertical movement of each piston 13, and thus a series of operating strokes (intake stroke, compression stroke, expansion) of the engine 1. It is driven to open and close by a valve mechanism 21 including a camshaft 20 and the like in conjunction with the stroke and the exhaust stroke).

  The cylinder head 12 is provided with an injector 32 that directly injects fuel into each combustion chamber 15 corresponding to each cylinder 2. Each injector 32 corresponds to fuel supply means of the present invention, and is configured to inject and supply fuel supplied from a fuel supply device (not shown) to each corresponding combustion chamber 15. In each combustion chamber 15, a combustible air-fuel mixture is formed by the fuel injected from the injector 32 and the air sucked from the intake passage 4 in the intake stroke.

  The cylinder head 12 is provided with a spark plug 33 in each combustion chamber 15 corresponding to each cylinder 2. Each spark plug 33 receives the ignition signal output from the ignition coil 34 and performs a spark operation. Both parts 33 and 34 constitute an ignition device that ignites a combustible air-fuel mixture formed in each combustion chamber 15. The combustible air-fuel mixture in each combustion chamber 15 explodes and burns by the spark operation of each spark plug 33 in the compression stroke, and the expansion stroke passes. Exhaust gas after combustion is discharged to the outside from each combustion chamber 15 through the exhaust port 17, the exhaust passage 5 and the catalytic converter 10 in the exhaust stroke. With combustion of the combustible air-fuel mixture in each combustion chamber 15, each piston 13 moves up and down, a series of operation strokes advance, and the crankshaft 3 rotates, whereby power is obtained in the engine 1. In the engine 1, the crankshaft 3 rotates twice (720 ° A rotation) every time a series of operation strokes is completed once in each cylinder 2.

  FIG. 2 schematically shows the configuration of each cylinder 2. As the crankshaft 3 rotates, the piston 13 moves up and down (stroke) between a top dead center (TDC) and a bottom dead center (BDC). The distance between the top dead center (TDC) and the bottom dead center (BDC) is the maximum stroke STmax of the piston 13.

  The cylinder head 12 is provided with an in-cylinder pressure sensor 42 for detecting the pressure in each combustion chamber 15 as the in-cylinder pressure PS corresponding to each cylinder 2.

  In this embodiment, as shown in FIG. 1, the intake passage 4 (intake manifold 51) downstream from the surge tank 8 is used to suppress the amount of intake air taken into one cylinder 2 of the four cylinders 2. An intake air suppression valve 36 of the present invention is provided. The intake air suppression valve 36 is provided assuming that the cylinder 2 is in the compression stroke when the engine 1 is stopped. The intake suppression valve 36 includes a butterfly valve 38 that is opened and closed by a motor 37. FIG. 3 is a schematic view of the engine system showing the arrangement of the electronic throttle device 7 and the intake air suppression valve 36 in the intake passage 4. The intake manifold 51 constituting the intake passage 4 includes a collecting pipe 51a connected to the surge tank 8, and the first (# 1), second (# 2), third (# 3) and fourth (#) from the collecting pipe 51a. 4) and four branch pipes 51b branching to the four cylinders 2. In this embodiment, assuming that the cylinder 2 that is in the compression stroke when the engine 1 is stopped is the first cylinder 2, the intake air suppression valve 36 is a branch pipe corresponding to the first cylinder 2. 51b. In other words, the intake air suppression valve 36 is provided in one branch pipe 51b in order to suppress the intake air sucked into the first cylinder 2. The intake air suppression valve 36 is normally opened in a fully open state, and is closed as necessary.

  Further, as shown in FIG. 1, the engine system is provided with an alternator 61 and a battery 62 that constitute a power supply device. The alternator 61 is configured to generate power by operating with power from the crankshaft 3. The electric power generated by the alternator 61 is supplied to various electrical components mounted on the automobile and charged to the battery 62. The alternator 61 includes an adjustment circuit 63 for adjusting the generated power. By controlling the adjustment circuit 63, the power generated by the alternator 61 is adjusted. By this adjustment, the load applied to the crankshaft 3 as a reaction force from the alternator 61 is adjusted, and the rotational speed of the crankshaft 3 is adjusted. In this embodiment, the alternator 61 corresponds to the rotation adjusting means of the present invention.

  As shown in FIG. 1, various sensors 41 to 47 provided in the engine 1 constitute an operation state detection unit for detecting the operation state of the engine 1. An accelerator sensor 43 is provided on the accelerator pedal 27 provided in the driver's seat. The accelerator sensor 43 detects the depression angle of the accelerator pedal 27 as the accelerator opening ACC, and outputs an electrical signal corresponding to the detected value. The water temperature sensor 44 provided in the engine 1 detects the temperature (cooling water temperature) THW of the cooling water flowing inside the cylinder block 11 and outputs an electrical signal corresponding to the detected value. A rotational speed sensor 45 provided in the engine 1 detects the rotational position (crank angle) and rotational speed (engine rotational speed) NE of the crankshaft 3, and outputs an electrical signal corresponding to the detected value. The sensor 45 is configured to detect the rotation of the timing rotor 28 fixed to one end of the crankshaft 3 for each predetermined angle. In this embodiment, the rotation speed sensor 45 and the timing rotor 28 correspond to the rotation detection means of the present invention. The intake pressure sensor 46 provided in the surge tank 8 detects the intake pressure PM in the surge tank 8 and outputs an electrical signal corresponding to the detected value. The oxygen sensor 47 provided in the exhaust passage 5 detects the oxygen concentration (output voltage) Ox in the exhaust gas discharged to the exhaust passage 5, and outputs an electrical signal corresponding to the detected value.

  The rotation detection means of this embodiment will be described in detail. FIG. 4 is a front view showing the relationship between the arrangement of the rotation speed sensor 45 and the timing rotor 28. In FIG. 4, the rotation speed sensor 45 is constituted by a crank sensor made of an MR element, and is disposed to face the outer periphery of the timing rotor 28 fixed to one end of the crankshaft 3. A plurality of protrusions (teeth) 28a are formed on the outer periphery of the timing rotor 28, and the rotation speed sensor 45 is disposed so as to face each tooth 28a. Most of the plurality of teeth 28a are formed, for example, every 10 ° C., and are missing teeth 28b formed at intervals of 30 ° C. at only one place. The rotation speed sensor 45 detects the passage of each tooth 28a and outputs a pulse signal when the timing rotor 28 rotates as the crankshaft 3 rotates. The engine speed NE can be obtained from the elapsed time between successive pulse signals.

  The engine system includes an electronic control unit (ECU) 50 that performs various controls. Various sensors 41 to 47 are connected to the ECU 50. The ECU 50 is connected to the motor 31, the injectors 32, the ignition coils 34, the motor 37, and the adjustment circuit 63, respectively.

  In this embodiment, the ECU 50 inputs signals output from the various sensors 41 to 47, and performs the fuel injection control, the ignition timing control, the idling stop control, and the like based on these signals, and the motor 31 and each injector 32. The ignition coils 34, the motor 37, and the adjustment circuit 63 are controlled. In this embodiment, the ECU 50 corresponds to the control means of the present invention.

  Here, the fuel injection control is to control the fuel injection amount and the injection timing by each injector 32 in accordance with the operating state of the engine 1. The ignition timing control is to control the ignition timing by each ignition plug 33 by controlling each ignition coil 34 according to the operating state of the engine 1. The idling stop control means that when a predetermined automatic stop condition is satisfied, the fuel supply by each injector 32 is stopped to automatically stop the engine 1, and when the predetermined restart condition is satisfied, the stop state is established. Injecting and supplying fuel from each injector 32 to each engine 1 and operating each spark plug 33 causes the fuel to burn and automatically restart the engine 1. The idling stop control includes engine rotation stop position control, which will be described later.

  As is well known, the ECU 50 includes a central processing unit (CPU), various memories, an external input circuit, an external output circuit, and the like. The memory stores a predetermined control program related to various controls of the engine 1. The CPU executes the various controls described above based on a predetermined control program based on detection signals of the various sensors 41 to 47 input via the input circuit.

  Here, the electronic throttle device 7 corresponds to the intake air amount adjusting valve of the present invention that opens and closes in order to adjust the intake air amount supplied to the combustion chamber 15 of each cylinder 2, but in this embodiment, the crankshaft 3 It also functions as a rotation adjusting means that operates to adjust the rotation of the rotation. That is, when a fuel cut is performed on the engine 1 in order to automatically stop the engine 1 from the idling operation state, the electronic throttle device 7 is operated to open the throttle valve 9 from the idle opening, so that the intake stroke The cylinder 2 is charged with intake air, a load is applied to the engine 1, the deceleration torque of the crankshaft 3 is changed, and the engine rotational speed NE is adjusted.

  Next, engine rotation stop position control in idling stop control will be described. FIG. 5 shows the contents from a flowchart. This control means the operation of the engine rotation stop position control device in this embodiment.

  When the process proceeds to this routine, in step 100, the ECU 50 determines whether or not an automatic stop condition for the engine 1 is satisfied. For example, the ECU 50 can determine whether the engine rotation speed NE has decreased to a predetermined rotation speed at which the engine 1 should be stopped as an automatic stop condition. If the determination result is affirmative, the ECU 50 proceeds to step 110.

  In step 110, the ECU 50 performs a fuel cut. That is, the fuel injection from the injector 32 is forcibly stopped at the timing of entering the intake stroke for the cylinder 2 that is in the intake stroke first after the automatic stop condition is satisfied, and thereafter the intake stroke of other cylinders 2 is also entered at the timing. The fuel injection from the injector 32 is forcibly stopped sequentially. Further, the ECU 50 sets the fuel cut flag XFC to “1”. The flag XFC is reset to “0” when the engine 1 is restarted.

  Next, at step 120, the ECU 50 controls the opening of the electronic throttle device 7 in order to open the throttle valve 9 from the idle opening by a predetermined opening (for example, “10 deg”). Further, the ECU 50 sets the throttle valve opening flag XSO to “1”. The flag XSO is reset to “0” when the engine 1 is restarted.

  Next, at step 130, the ECU 50 calculates the total crank angle TCA of the crankshaft 3 based on the detection value of the rotational speed sensor 45. Here, the total crank angle TCA is the crank angle until the crankshaft 3 makes two rotations (720 ° C. A rotation) from the reference position (0 ° C. A) until a series of operation strokes is completed once in each cylinder 2. Mean cumulative change (0-720 ° C.).

  Next, in step 140, the ECU 50 sets a stop position range SPR when the rotation of the crankshaft 3 stops. The ECU 50 can set the stop position range SPR as a range of the total crank angle TCA. Corresponding to this stop position range SPR, it is possible to specify one cylinder 2 that is in the compression stroke when the engine 1 is stopped.

  Next, in step 150, the ECU 50 sets the valve closing timing TIVC of the intake air suppression valve 36 from the set stop position range SPR.

  Next, in step 160, the ECU 50 starts closing the intake air suppression valve 36 at the set valve closing timing TIVC. Further, the ECU 50 sets the intake air suppression flag XRC to “1”. The flag XRC is reset to “0” when the engine 1 is restarted. Thereby, the filling of the intake air into the first cylinder 2 is suppressed.

  Next, at step 170, the ECU 50 corrects the deviation between the total crank angle TCA and the stop position range SPR due to the start of closing of the intake suppression valve 36. For example, the ECU 50 can obtain a deviation amount of the total crank angle TCA according to the closing amount of the intake air suppression valve 36 by referring to a map as shown in FIG. The deviation between the total crank angle TCA and the stop position range SPR can be corrected from the obtained deviation amount. In the map of FIG. 6, the deviation amount of the total crank angle TCA is set so as to decrease as the closing amount of the intake suppression valve 36 increases.

  Next, at step 180, the ECU 50 causes the engine 1 to stop at the engine rotational speed (top dead center rotational speed) TDCNE when each cylinder 2 passes the compression top dead center based on the detection value of the rotational speed sensor 45. It is determined whether or not it is within a predetermined range NR1 correlated with the position of the piston 13 at that time. If this determination result is negative, the ECU 50 proceeds to step 190. If this determination result is affirmative, the ECU 50 proceeds to step 210.

  In step 190, the ECU 50 calculates the target power generation amount TEG and the like by the alternator 61 from the deviation of the top dead center rotational speed TDCNE from the predetermined range NR1.

  Next, in step 200, the ECU 50 causes the alternator 61 to generate power based on the calculated target power generation amount TEG. For this purpose, the ECU 50 controls the adjustment circuit 63 based on the target power generation amount TEG.

  In step 210 after shifting from step 180 or step 200, the ECU 50 determines whether or not the top dead center rotational speed TDCNE is equal to or less than a predetermined value N1. When this determination result is negative, ECU 50 returns the process to step 180, and when this determination result is affirmative, the process proceeds to step 220.

  In step 220, the ECU 50 fixes the power generation amount by the alternator 61 or stops power generation. Next, in step 230, the ECU 50 ends the closing of the intake air suppression valve 36.

  In step 240, the ECU 50 determines whether the engine 1 has stopped. The ECU 50 returns the process to step 220 when this determination result is negative, and returns the process to step 100 when this determination result is affirmative.

  Here, an example of the rotation stop position control will be described with reference to FIG. FIG. 7 is a time chart showing the behaviors of (a) engine speed NE, (b) total crank angle TCA, (c) fuel cut flag XFC, (d) throttle valve opening flag XSO, and (e) intake air suppression flag XRC. Show. In FIG. 9, as shown in (a), in a state where the engine rotational speed NE (idle rotational speed) is a predetermined target rotational speed, as shown in FIG. The fuel cut is started in the intake stroke, the fuel cut flag XFC is set to “1”, the electronic throttle device 7 is opened as shown in (d), and the throttle valve opening flag XSO is set to “1”. Then, the engine speed NE starts to decrease from time t1. Thereafter, at time t2 slightly delayed, as shown in (e), the intake suppression valve 36 is closed and the intake suppression flag XRC becomes “1”. Thereafter, as shown in (a) and (b), the rotation of the crankshaft 3 stops at the time t4 when the crankshaft 3 makes two rotations (720 ° C. A rotation) from the time t3.

  According to the engine rotation stop position control device in this embodiment described above, when the engine 1 is stopped, the ECU 50 causes the rotation speed sensor 45 to stop the crankshaft 3 at a predetermined rotation position (crank angle). Based on the detected crank angle, each injector 32 is controlled so as to start the fuel cut of each cylinder 2 from a specific cylinder 2, and the electronic throttle device 7 is controlled to open to fill each cylinder 2 with intake air. To do. Here, when the ECU 50 stops the crankshaft 3 at a predetermined crank angle, the ECU 50 starts the fuel cut from the specific cylinder 2 and controls the electronic throttle device 7 to open, and then controls the intake suppression valve 36 to close. To do. Therefore, a negative pressure is applied to the cylinder 2 in which the charging of the intake air is suppressed when the intake air suppression valve 36 is closed, and the intake air is charged according to the operation stroke in the other cylinders 2. For this reason, when the engine 1 is stopped, the first cylinder 2 that is in the compression stroke is in a state close to negative pressure, and the cylinder 2 that is in the expansion stroke is at positive pressure or atmospheric pressure. 2 can be adjusted to a pressure state advantageous for restarting the engine 1. As a result, the engine 1 can be restarted more smoothly and reliably.

  In this embodiment, by closing the intake air suppression valve 36, a load is applied to the crankshaft 3 and the crank angle may shift. Here, when the intake control valve 36 is controlled to be closed, the deviation of the crank angle detected by the rotation speed sensor 45 is corrected and reduced. For this reason, when the engine 1 stops, the crankshaft 3 can be brought close to a predetermined crank angle and stopped.

  In this embodiment, the load applied to the crankshaft 3 increases as the opening of the intake suppression valve 36 decreases, and the crank angle deviation detected by the rotational speed sensor 45 increases. Here, as the opening degree of the intake air suppression valve 36 becomes smaller, the crank angle deviation is corrected to be larger, so this crank angle deviation is accurately corrected. For this reason, when the engine 1 stops, the crankshaft 3 can be accurately stopped at a predetermined crank angle.

  In this embodiment, the ECU 50 controls the alternator 61 to adjust the top dead center rotational speed TDCNE within the predetermined range NR1 when the detected top dead center rotational speed TDCNE is not within the predetermined range NR1. Accordingly, a load is applied to the crankshaft 3, and the top dead center rotational speed TDCNE is adjusted within a predetermined range NR1 suitable for causing the rotation of the crankshaft 3 to stop. For this reason, when the engine 1 stops, the crankshaft 3 can be accurately stopped at a predetermined crank angle.

  In this embodiment, the ECU 50 fixes or stops the supply of the load to the crankshaft 3 by the alternator 61 when the detected top dead center rotational speed TDCNE is equal to or less than the predetermined value N1 within the predetermined range NR1. Accordingly, the supply of the load to the crankshaft 3 is fixed or stopped, and the top dead center rotation speed TDCNE is fixed to a rotation speed suitable for directing the rotation of the crankshaft 3 to the stop. For this reason, even if the load applied to the crankshaft 3 fluctuates in the middle, the crankshaft 3 can be more accurately stopped at a predetermined crank angle when the engine 1 is stopped.

  In addition, this invention is not limited to the said embodiment, A part of structure can also be changed suitably and implemented in the range which does not deviate from the meaning of invention.

  (1) In the above-described embodiment, the intake air suppression valve 36 is provided corresponding to only the cylinder 2 that is in the compression stroke when the engine 1 is stopped among the four cylinders 2. On the other hand, an intake air suppression valve can be provided corresponding to a cylinder other than the cylinder that becomes the compression stroke when the engine is stopped.

  (2) In the above embodiment, the alternator 61 is used as the rotation adjusting means of the present invention. However, a device other than the alternator, for example, a variable valve timing mechanism (VVT) may be used as the rotation adjusting means.

  (3) In the above embodiment, the present invention is embodied in the engine 1 having the four cylinders 2. However, the number of cylinders of the engine is not limited to four, and may be embodied in an engine having any number of cylinders that can be realized. it can.

  (4) The engine system in the above embodiment may be mounted on a vehicle that uses only the engine 1 as a driving source, or may be mounted on a hybrid vehicle that uses an engine and a motor as driving sources. There may be.

  The present invention can be used for an idle stop system employed in an engine.

1 Engine 2 Cylinder 3 Crankshaft (Rotating shaft)
7 Electronic throttle device (intake air amount adjustment valve)
9 Throttle valve 32 Injector (fuel supply means)
36 Intake Suppression Valve 45 Rotational Speed Sensor (28 and 45 constitute a rotation detecting means)
50 ECU (control means)
61 Alternator (rotation adjustment means)

Claims (5)

An engine rotation stop position control device for controlling an engine rotation shaft to stop at a predetermined rotation position,
The engine is a reciprocating engine including a plurality of cylinders, and is configured to rotate the rotating shaft by burning the fuel supplied by the fuel supply means in the cylinders;
An intake air amount adjustment valve for adjusting the intake air amount supplied to each cylinder;
Rotation detection means for detecting the rotation position and rotation speed of the rotation shaft;
In order to stop the rotation shaft at the predetermined rotation position, the fuel supply means is configured to start the fuel supply of each cylinder from a specific cylinder based on the rotation position detected by the rotation detection means. And an engine rotation stop position control device comprising: control means for controlling the opening of the intake air amount adjustment valve in order to fill each cylinder with intake air.
An intake air suppression valve for suppressing charging of intake air into at least one of the plurality of cylinders;
The control means, when stopping the rotating shaft at the predetermined rotational position, starts stopping the fuel supply, performs opening control of the intake air amount adjustment valve, and then performs closing control of the intake air suppression valve. An engine rotation stop position control device.   2. The engine rotation stop position control device according to claim 1, wherein the control unit corrects a deviation of the rotation position detected by the rotation detection unit when the intake suppression valve is controlled to be closed. 3. .   3. The engine rotation stop position control device according to claim 2, wherein the control means corrects the shift of the rotational position to a greater extent as the opening of the intake suppression valve becomes smaller. A rotation adjusting means for adjusting a rotation speed of the rotating shaft by applying a load to the rotating shaft;
When the top dead center rotation speed detected by the rotation detection means is not within a predetermined range when each cylinder is at the top dead center, the control means sets the top dead center rotation speed within the predetermined range. 4. The engine rotation stop position control device according to claim 1, wherein the rotation adjusting means is controlled for adjustment.   When the top dead center rotation speed detected by the rotation detection unit is equal to or less than a predetermined value within the predetermined range, the control unit fixes the supply of the load to the rotation shaft by the rotation adjustment unit or The engine rotation stop position control device according to claim 4, wherein the rotation stop position control device is stopped.

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