JP4701698B2 - Vehicle engine starting device - Google Patents

Description

  The present invention relates to an engine starting device that automatically stops an engine once at the time of deceleration of a vehicle and automatically starts the stopped engine.

In recent years, in order to reduce fuel consumption and reduce CO ₂ emissions, the engine is automatically stopped once during idling, and then the engine is automatically restarted when a restart condition such as a start operation is established. Such engine starting devices have been developed.

  In this type of engine starter, an automatic transmission mechanism is known to be in a neutral state in order to cut off the influence of vibration and reverse drive from the wheel side after the engine has been automatically stopped (Patent Literature). 1).

In addition, after the engine is automatically stopped, the engine is restarted when the non-drive position (corresponding to the neutral state in this specification) is changed to the drive position (corresponding to the drive state in this specification), and the drive position is established. It is also known to perform rapid pressure increase control that temporarily increases pressure for a predetermined time temporarily at the initial stage of oil supply to the clutch for the purpose (see Patent Document 2).
JP-A-7-266932 JP-A-11-351371

  However, in conventional devices such as those disclosed in Patent Documents 1 and 2, if the engine is automatically stopped on an uphill road, there is a possibility that the vehicle may move backward for a moment when the vehicle restarts with engine restart. For example, this is the case where the engine is automatically stopped when the driver steps on the brake and stops on an uphill road, and the engine is restarted when the driver releases the brake with the intention of starting. Equivalent to. In such a case, if the automatic transmission mechanism is in the neutral state while the engine is automatically stopped as in Patent Documents 1 and 2, the automatic transmission is switched to the drive state after the driver releases the brake. In the meantime, the wheel is easily rotatable in the backward direction. On the uphill road, gravity acts so as to move the vehicle backward, so that the vehicle moves backward due to gravity while the wheels are easily rotated in the backward direction, that is, until the switching of the automatic transmission mechanism is completed. It is.

  As shown in Patent Document 2, it is possible to reduce the reverse amount to some extent by quickly switching from the neutral state to the drive state, but automatic shifting without causing the passenger to feel an unpleasant shock. In order to switch the mechanism from the neutral state to the driving state (usually by switching the hydraulic clutch using a friction element), it is necessary to engage the clutch over a certain amount of time, and avoid the concern of vehicle retreat during that time. I can't. Even if the automatic transmission mechanism is instantaneously switched to the drive state, it takes a certain amount of time until the driving force that can resist gravity is generated after the engine starts restarting. Recession concerns are inevitable.

  On the other hand, a slope start assist device (so-called hill holder) that keeps the brake hydraulic pressure for a predetermined period even when the driver releases the brake on the uphill road so that the vehicle does not move backward is also known. It is provided in a vehicle equipped with a manual transmission mechanism. In the case of a vehicle equipped with an automatic transmission mechanism, the driver releases the brake in a normal driving state when starting on an uphill road where automatic engine stop is not performed, so there is almost no need for a hill holder. Because. Therefore, providing a hill holder in a vehicle equipped with an automatic transmission mechanism as a solution to the above problem unnecessarily increases the complexity and cost of the structure.

  The present invention has been made in view of the above circumstances, and the automatic transmission mechanism is neutralized to effectively influence the influence from the wheel side while the engine is automatically stopped under predetermined conditions to improve fuel efficiency. Even if the engine is automatically stopped on an uphill road, the vehicle can be controlled to reverse when starting with engine restart without using a special slope start assist device. An engine starting device is provided.

According to a first aspect of the present invention, when the engine automatic stop condition is satisfied, the vehicle engine starter stops the fuel supply to stop the engine, and the engine restart condition in the automatic stop state is satisfied. An engine starter for a vehicle having stop / restart control means for automatically restarting the engine by causing combustion in a cylinder in an expansion stroke at least when the engine is stopped when the engine is stopped. The drive state is configured to switch between a drive state in which the drive force can be transmitted to a neutral state in which the drive force transmission is disconnected, and a reverse that restricts the rotation of the wheel in the reverse direction in the neutral state. comprising an automatic speed change mechanism which can no prohibited neutral state, an inclined state detecting means for detecting the inclination of the road surface, the automatic transmission mechanism , At least one of the high gear than the lowest speed of the gear stage in the drive state, is configured to be made and a retracted prohibited gear position for regulating the rotation of the retracting direction of the wheel, the stop restart control When the engine is automatically stopped on the road surface determined to be an uphill road having a predetermined inclination or higher by the inclining state detecting means, the automatic transmission mechanism is set to the reverse prohibition neutral state, and the engine on the uphill road is When the engine is restarted, it is switched from the reverse prohibition neutral state to the low speed stage via the reverse prohibition speed stage, and the automatic transmission mechanism is switched from the reverse prohibition speed stage to the lower speed stage. characterized in that the cylinder automatic was in stop in the intake stroke and since it was first exceeds the compression top dead center after the engine restart To.

According to a second aspect of the present invention, in the vehicle engine starter according to the first aspect of the present invention, the vehicle is provided with an accelerator sensor that detects an accelerator opening, and the stop / restart control means has an accelerator opening at the time of the engine restart. When the value is equal to or greater than a predetermined value, the intake flow rate is corrected to decrease until the shift stage switching of the automatic transmission mechanism is completed.

According to a third aspect of the present invention, in the engine starter for a vehicle according to the first or second aspect , the stop / restart control means has an inclination of the road surface detected by the inclination state detecting means equal to or greater than a predetermined value. In this case, the intake air flow rate is corrected to increase in a predetermined period in the engine restart process.

According to the first aspect of the present invention, it is possible to improve the fuel consumption by automatically stopping the engine when the automatic engine stop condition is satisfied. In that case, the influence from the wheel side can be effectively suppressed by setting the automatic transmission mechanism to the neutral state. In addition, the automatic transmission mechanism is set to the neutral state where the automatic transmission mechanism is prohibited on the uphill road. It is possible to regulate without using a hill holder or the like. In addition, even when the forward drive force is insufficient at the stage of switching from the reverse prohibition neutral state to the drive state, at least the vehicle can reverse by setting the shift stage of the automatic transmission mechanism to the reverse prohibition shift stage. Sufficient driving force on the uphill road can be obtained by effectively controlling the vehicle and starting at a lower speed.
In addition, since the cylinder that was in the intake stroke during the automatic engine stop has exceeded the compression top dead center for the first time after engine restart, switching to the low speed stage is performed when the engine restart is ensured. A more stable and smooth start can be performed.

According to the second aspect of the present invention, during a shift from the reverse shift prohibition speed to a lower speed, the intake flow rate is reduced to reduce the transmission driving force to the automatic transmission mechanism. Can be relaxed.

According to the invention of claim 3 , even on a steep uphill road, the engine output can be increased by increasing the intake flow rate, and the start driving force can be increased to perform a smooth start. In addition, when the vehicle is started by switching from a reverse-prohibited shift speed to a lower speed, even if the low-speed speed is a reverse speed, it is possible to suppress the reverse of the vehicle as much as possible by increasing the forward drive force. it can.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings.

  1 and 2 show a schematic configuration of a four-cycle spark ignition engine according to an embodiment of the present invention. This engine includes an engine main body 1 having a cylinder head 10 and a cylinder block 11 and an ECU 2 (see FIG. 9) for engine control. The engine main body 1 includes a plurality of cylinders (four in the illustrated embodiment). Cylinders) 12A to 12D. A piston 13 connected to the crankshaft 3 via a connecting rod is fitted into each cylinder 12A to 12D, and a combustion chamber 14 is formed above the piston 13.

  A spark plug 15 is provided at the top of the combustion chamber 14 of each cylinder 12 </ b> A to 12 </ b> D, and the tip of the plug faces the combustion chamber 14. Further, a fuel injection valve 16 that directly injects fuel into the combustion chamber 14 is provided at a side portion of the combustion chamber 14. The fuel injection valve 16 includes a needle valve and a solenoid (not shown). When a pulse signal is input, the fuel injection valve 16 is driven and opened for a time corresponding to the pulse width at the pulse input timing. It is comprised so that the quantity of fuel according to may be injected. The injection direction of the fuel injection valve 16 is set so that fuel is injected toward the vicinity of the spark plug 15. The fuel injection valve 16 is supplied with fuel via a fuel supply passage or the like by a fuel pump (not shown), and can supply a fuel pressure higher than the pressure in the combustion chamber during the compression stroke. Is configured.

  An intake port 17 and an exhaust port 18 are opened to the combustion chambers 14 of the cylinders 12A to 12D, and an intake valve 19 and an exhaust valve 20 are provided in these ports 17 and 18. The intake valve 19 and the exhaust valve 20 are driven by a valve operating mechanism including a camshaft and the like (not shown). As described later in detail, the opening / closing timings of the intake / exhaust valves 19 and 20 of the cylinders 12A to 12D are set so that the cylinders 12A to 12D perform a combustion cycle with a predetermined phase difference.

  An intake passage 21 and an exhaust passage 22 are connected to the intake port 17 and the exhaust port 18. As shown in FIG. 2, the downstream side of the intake passage 21 close to the intake port 17 is an independent branch intake passage 21a corresponding to each of the cylinders 12A to 12D. The upstream ends of the branch intake passages 21a are respectively It communicates with the surge tank 21b. A common intake passage 21c is provided upstream of the surge tank 21b, and an intake flow rate adjusting means including a throttle valve 23 driven by an actuator 24 is disposed in the common intake passage 21c. An air flow sensor 25 for detecting the intake flow rate and an intake pressure sensor 26 for detecting the intake pressure (negative pressure) are disposed on the upstream side and the downstream side of the throttle valve 23, respectively.

  The engine body 1 is also provided with an alternator (generator) 28 connected to the crankshaft 3 by a timing belt or the like. The alternator 28 is configured to be able to adjust the output voltage by controlling the current of the field coil (not shown), and based on the control signal from the ECU 2, the target corresponding to the electric load of the vehicle, the voltage of the vehicle battery, etc. The control of the generated current is executed.

  Further, the engine is provided with two crank angle sensors 30 and 31 for detecting the rotation angle of the crankshaft 3, and the rotation speed of the engine is detected based on a detection signal output from one crank angle sensor 30. In addition, the rotation direction and the rotation angle of the crankshaft 3 are detected based on the detection signals out of phase output from the crank angle sensors 30 and 31.

  Further, the engine is provided with a cam angle sensor 32 for detecting a specific rotational position of the camshaft and outputting it as a cylinder identification signal, and a water temperature sensor 33 for detecting the coolant temperature of the engine, as shown in FIG. Further, an accelerator sensor 34 that detects an accelerator opening corresponding to the accelerator operation amount of the driver, a brake sensor 35 that detects that the driver has operated the brake, and an oil temperature of an automatic transmission mechanism 50 that will be described later are detected. An oil temperature sensor 37, a vehicle speed sensor 38 for detecting the vehicle speed, an operating pressure sensor 39 for detecting an operating pressure corresponding to each friction element in the automatic transmission mechanism 50, and an inclination sensor 40 (inclined state) for detecting a road surface inclination state. Detecting means). Each detection signal output is input to the ECU 2.

  Further, as shown in FIG. 3, the engine is connected to an automatic transmission mechanism 50 through a crankshaft 3 as an output shaft thereof. The automatic transmission mechanism 50 includes a torque converter 51 connected to the crankshaft 3 and a multi-stage transmission mechanism 52 connected to a turbine shaft 59 that is an output shaft of the torque converter 51, and includes a plurality of frictions included therein. By switching the elements intermittently, it is possible to switch between a neutral state in which the transmission of the driving force to the wheel side is cut off and a driving state in which the driving force can be transmitted to the wheel side.

  The torque converter 51 includes a pump cover 53 connected to the crankshaft 3, a pump impeller 54 formed integrally with the pump cover 53, and a turbine (turbine liner) 55 installed so as to face the pump impeller 54. In the meantime, a stator 58 attached to a case 57 via a one-way clutch 56 is provided. The space in the pump cover 53 is filled with oil (working oil) as a working fluid, and the driving force of the pump impeller 54 is transmitted to the turbine 55 through the working oil. The driving force is transmitted to and from the multi-stage transmission mechanism 52 via the turbine shaft 59 connected to the turbine 55.

  The case 57 is provided with a turbine rotation sensor 36 that detects the rotation speed of the turbine 55 in a state of facing an outer peripheral surface of a forward clutch 67 (described later) that rotates integrally with the turbine shaft 59. Yes. Specifically, the turbine rotation sensor 36 has a tip portion disposed opposite to the outer peripheral surface of the drum of the forward clutch 67, and a spline-like unevenness provided on the outer peripheral surface of the drum is displaced by the rotation of the drum. The rotational speed of the turbine 55 is detected through the rotational speed of the turbine shaft 59 by detecting a periodic change in the induced voltage generated.

  A hollow rotary shaft 60 is connected to the pump impeller 54, and an oil pump 61 is attached to the rear end portion (the end portion opposite to the engine body 1 side) of the shaft 60. In addition to the oil pump 61, an electric oil pump 62 (see FIG. 7) is provided in the case 57, and these oil pumps 61 and 62 are connected to a hydraulic control mechanism 63 described later. Then, the ECU 2 performs switching control between the oil pump 61 and the electric oil pump 62 and performs control such as switching of the oil path (fluid path) of the hydraulic control mechanism 63 and setting of the line pressure. Friction elements 67 to 71, which will be described later, are intermittently (fastened or released) by hydraulic control (pressure control of the working fluid).

  The reason why the electric oil pump 62 is provided separately from the oil pump 61 is that it is difficult to supply a desired line pressure depending on the oil pump 61 because the engine rotation speed is not sufficient when the engine is stopped or at the start of the engine. In this case, the line pressure is ensured, and the timing for switching between the oil pump 61 and the electric oil pump 62 is set from this viewpoint.

  The torque converter 51 is further provided with a lock-up clutch 64 that is interposed between the pump cover 53 and the turbine 55 and directly connects the crankshaft 3 and the turbine 55 via the cover 53. The lockup clutch 64 is connected to the oil pump 61 and the electric oil pump 62 via a hydraulic control mechanism 63, and on / off control of various solenoid valves provided in the hydraulic control mechanism 63 according to the vehicle speed. By doing so, the oil passage is switched, and the lockup clutch 64 is engaged / disengaged.

  On the other hand, the multi-stage speed change mechanism 52 includes first and second planetary gear mechanisms 65 and 66 and fastening elements (a plurality of friction elements 67 to 71 such as clutches and brakes) for switching a power transmission path including the planetary gear mechanisms 65 and 66. And a one-way clutch 72), and is configured to switch forward speed, neutral state, and reverse speed by intermittently connecting these fastening elements 67 to 72 according to a shift range (D range, N range, R range, etc.). ing.

  In this embodiment, as will be described later, as a special form of the N range, it is possible to select a reverse prohibition neutral state (hereinafter also referred to as a reverse prohibition N ′ range) that restricts rotation of the wheels in the reverse direction. It is configured.

  Further, the N range, reverse prohibition N ′ range or D range mentioned here does not necessarily indicate the shift operation position by the shift lever, but means a substantial transmission state in which each solenoid valve is controlled. Accordingly, the case where the automatic transmission mechanism 50 is set to the N range (neutral) state or the reverse prohibition N ′ range state by the control of each solenoid valve while the shift operation position by the shift lever remains in the D range position is included.

  The first and second planetary gear mechanisms 65 and 66 are respectively provided with sun gears 65a and 66a, and a plurality of (for example, three) planetary gears 65b and 66b that are disposed around and mesh with the sun gears 65a and 66a. A ring gear of the first planetary gear mechanism 65, which includes carriers 65c and 66c for supporting the planetary gears 65b and 66b, and ring gears 65d and 66d that are arranged so as to surround the planetary gears 65b and 66b. 65d and the carrier 66c of the second planetary gear mechanism 66 are coupled, and the carrier 65c of the first planetary gear mechanism 65 and the ring gear 66d of the second planetary gear mechanism 66 are coupled to each planetary gear mechanism 65, 66. Can be linked.

  The friction element includes a forward clutch 67 interposed between the turbine shaft 59 and the sun gear 65a of the first planetary gear mechanism 65, and a reverse clutch 68 interposed between the turbine shaft 59 and the sun gear 66a of the second planetary gear mechanism 66. A 3-4 clutch 69 interposed between the turbine shaft 59 and the carrier 66c of the second planetary gear mechanism 66, a 2-4 brake 70 for fixing the sun gear 66a of the second planetary gear mechanism 66, and these planets. A low reverse brake 71 or the like interposed in parallel between the gear mechanisms 65 and 66 and the case 57 is provided. The one-way clutch 72 only locks the carrier 65c and the ring gear 65d in one direction (the driving direction of the crankshaft 3) (unlocked) and prevents it from rotating in the opposite direction. These fastening elements 67 to 72 are intermittently connected, and the power transmission path connected to the output gear 73 is changed or disconnected.

  As the output gear 73 rotates, the driving force is transmitted to the left and right axles 78 and 79 via the wheels, that is, the transmission gears 74, 75 and 76 and the differential mechanism 77. The axles 78 and 79 are configured to rotate integrally with a wheel (drive wheel) (not shown).

  The relationship between the intermittent state of these fastening elements 67-72 and a gear stage is shown in FIG. In FIG. 4, ◯ indicates a state in which the fastening elements 67 to 72 are fastened or locked, and no mark indicates a state in which they are released or unlocked. Accordingly, in the R range, the reverse clutch 68 and the low reverse brake 71 are engaged, and in the N range (neutral range), all the engagement elements 67 to 72 are released / unlocked. In the reverse prohibition N ′ range, the 2-4 brake 70 is engaged, and the one-way clutch 72 is locked (indicated by a circle with a parenthesis because it locks when the wheel is about to rotate in the reverse direction). Further, at the first speed of the D range (drive range), the forward clutch 67 is engaged and the one-way clutch 72 is locked, and at the second speed, the forward clutch 67 and the 2-4 brake 70 are engaged. The forward clutch 67 and the 3-4 clutch 69 are engaged at the third speed, and the 3-4 clutch 69 and the 2-4 brake 70 are engaged at the fourth speed.

  FIG. 5 is a schematic diagram showing the driving force transmission path of the automatic transmission mechanism 50 and the rotation direction of each part in the D range first speed. In this figure, when viewed from the left front side, the left rotation is the forward rotation direction, and the right rotation is the reverse rotation direction. When the engine is in a normal operating state, the turbine shaft 59 rotates in the forward direction. Further, when the vehicle is in the forward traveling state, the transmission gear 76 rotates in the forward rotation direction together with the axles 78 and 79.

  At the first speed in the D range shown in FIG. 5, the turbine shaft 59 rotates in the forward rotation direction, and the rotation and driving force are transmitted to the sun gear 65 a through the forward clutch 67. Further, it is transmitted to the planetary gear 65b, and this planetary gear 65b rotates in the reverse direction. Here, since the rotation of the ring gear 65d in the reverse rotation direction is restricted when the one-way clutch 72 is locked, the planetary gear 65b rotates in the reverse rotation direction around the support shaft (carrier 65c), and the carrier 65c. It integrally rotates around the sun gear 65a in the forward rotation direction. That is, the carrier 65c rotates in the forward rotation direction. The rotation and driving force of the carrier 65c in the forward rotation direction are transmitted to the output gear 73 and the transmission gears 74, 75, and 76. 3 is transmitted to the axles 78 and 79 through the differential mechanism 77 as shown in FIG.

  On the other hand, since the carrier 65c is connected to the ring gear 66d, the ring gear 66d rotates in the forward rotation direction. Further, since the carrier 66c is connected to the ring gear 65d, and the ring gear 65d is stopped by the locking of the one-way clutch 72, the carrier 66c is also stopped. Therefore, the planetary gear 66b rotates in the forward rotation direction. The sun gear 66a meshing with the planetary gear 66b rotates in the reverse direction.

  If the automatic transmission mechanism 50 is set to the D range first speed shown in FIG. 5 in a state where the engine is stopped (no input from the turbine shaft 59), the transmission gear 76 may be reversely rotated from the wheel side. it can. In other words, the vehicle can move backward.

  FIG. 6 is a schematic diagram showing the driving force transmission path of the automatic transmission mechanism 50 and the rotation direction of each part in the D range second speed. The definition of the rotation direction conforms to FIG.

  As shown in FIG. 4, the D range second speed is obtained by further engaging the 2-4 brake 70 from the D range first speed in which the forward clutch 67 is engaged. As described above, in the D range first speed, the sun gear 66a rotates in the reverse direction. When the 2-4 brake 70 is engaged from this state, the sun gear 66a stops. For this reason, the planetary gear 66b rotates around the sun gear 66a in the forward direction integrally with the carrier 66c while rotating in the forward direction around the support shaft (carrier 66c). That is, at the first speed, the one-way clutch 72 restricts the rotation in the reverse direction, and the stopped carrier 66c rotates in the normal direction (the one-way clutch 72 is unlocked for the rotation in the normal direction). .

  At this time, the planetary gear 65b rotates around the sun gear 65a in the forward rotation direction integrally with the carrier 65c while rotating in the reverse rotation direction around the carrier 65c as in the first speed. However, unlike the first speed, since the ring gear 65d rotates in the forward rotation direction, the rotational speed of the carrier 65c is relatively higher than that in the first speed. Thereafter, as in the first speed, the rotation and driving force of the carrier 65c in the forward rotation direction are transmitted to the output gear 73 and the transmission gears 74, 75, and 76.

  If the automatic transmission mechanism 50 is in the D range second speed shown in FIG. 6 with the engine stopped (no input from the turbine shaft 59), the transmission gear 76 is rotated in the reverse direction from the wheel side. It is regulated. This is because rotating the transmission gear 76 in the reverse direction is not only rotating the ring gear 66d in the reverse direction, but in the second speed state where the 2-4 brake 70 is engaged and the sun gear 66a is stopped. This is because the carrier 66c needs to be rotated in the reverse direction in order to perform this, because the reverse rotation of the carrier 66c is restricted by the one-way clutch 72.

  In other words, the second speed of the D range is a shift stage on the higher speed side than the first speed, and is also a reverse prohibition shift stage that restricts rotation in the reverse direction (reverse direction) of the wheel.

  Moreover, the restriction | limiting of the said reverse rotation in D range 2nd speed acts irrespective of the presence or absence of the fastening of the forward clutch 67. FIG. When the 2-4 brake 70 is kept engaged and the forward clutch 67 is disengaged with respect to the state of the second speed in the D range, the driving force transmission from the engine side is cut off so that the neutral state is reached. Rotation is regulated. In other words, the reverse prohibition N ′ range is set (see the N ′ range in FIG. 4).

  The description of the operation of each part of the automatic transmission mechanism 50 at the third speed and the fourth speed of the D range is omitted, but the friction elements 67 to 71 are fastened sequentially by fastening and releasing in a combination as shown in FIG. (The rotational speed of the transmission gear 76 is relatively greater than the input rotational speed of the turbine shaft 59).

  The friction elements 67 to 71 are connected to the oil pump 61 and the electric oil pump 62 through the hydraulic control mechanism 63 (see FIG. 7), similarly to the lock-up clutch 64, and the ECU 2 uses the first and first to be described later. The two-shift solenoid valves 83 and 84 and the first to third duty solenoid valves 85 to 87 are driven to switch and change the oil passages, hydraulic pressures, etc., and is intermittently performed.

  Specifically, the hydraulic control mechanism 63 includes a hydraulic control circuit as shown in FIG. 7, and this hydraulic control circuit is connected to the oil pump 61 and the electric oil pump 62 so that the original pressure is supplied from the pumps 61 and 62. Supplied. The hydraulic control mechanism 63 is arranged in the vicinity of the downstream side of the pumps 61 and 62 in the line 81 and the line 81 (oil passage) connected from the pumps 61 and 62 to the hydraulic chambers (not shown) of the friction elements 67 to 71. The first and second shift solenoid valves 83 and 84 (hereinafter simply referred to as “first and second SV”) for turning ON / OFF the regulator valve 82 provided for regulating the line pressure and the various valves for switching the lines communicating with the pumps 61 and 62. And first to third duty solenoid valves 85 to 87 (hereinafter simply referred to as “first to third DSVs”) for adjusting the operating pressure based on the duty value output from the ECU 2. In addition, 1st and 2SV83,84 and 1st-3rd DSV85-87 are comprised as a three-way valve. Further, a switching valve 91 for switching the oil supply source between the oil pump 61 and the electric oil pump 62 is provided on the oil passage connecting the pumps 61 and 62 and the line 81.

  Then, by operating various valves based on the vehicle speed, throttle opening, engine rotational speed, turbine rotational speed, and the like, the friction elements 67 to 71 are intermittently switched, so that the automatic transmission mechanism 50 is switched between a plurality of stages to correspond to the vehicle speed and the like. The ECU 2 is configured to perform control for selecting the gear according to the position of the shift lever or automatically. FIG. 8 shows combinations of operating states for the respective speeds of the solenoid valves 83 to 87. In FIG. 8, the circles indicate ON for the first and second SVs 83 and 84, and OFF for the first to third DSVs 85 to 87, both of which connect the upstream line to the downstream line. A state in which the original pressure is used as it is or as an operating pressure is supplied to the downstream side, and the x mark indicates that the first and second SVs 83 and 84 are OFF, and the first to third DSVs 85 to 87 are ON. Also shows a state in which the upstream line is blocked and the downstream line is drained.

  For example, the operation of the hydraulic control mechanism 63 when the first speed is selected for the multi-stage transmission mechanism 52 will be described. As shown in FIG. 8, only the third DSV 87 is operated to restore the upstream line pressure. An operating pressure is generated as the pressure, and this operating pressure is supplied to the lock-up control valve 88 via the line 81b. At this point, the spool of the lock-up control valve 88 is positioned on the right side, so that the forward clutch pressure (operating pressure) is further supplied to the hydraulic chamber of the forward clutch 67 via the forward clutch line 81c. The forward clutch 67 is engaged.

  Further, when the second gear (which is also a reverse prohibition gear) is selected, the first DSV 85 and the third DSV 87 operate as shown in FIG. The operation of the third DSV 87 and the engagement of the forward clutch 67 are the same as in the case of the first gear. Further, the operating pressure generated by the operation of the first DSV 85 is supplied to the engagement chamber of the 2-4 brake 70 via the line 81d, and the 2-4 brake 70 is engaged.

  In the case of the reverse prohibition N ′ range, only the first DSV 85 is operated as shown in FIG. Therefore, the forward clutch 67 is released and the 2-4 brake 70 is engaged.

  FIG. 9 is a block diagram of the engine starting device of the present embodiment. The ECU 2 includes a computer having a CPU, ROM, RAM, and the like. Specifically, various operations of the vehicle are controlled by the CPU executing a program stored in advance in the ROM (or RAM). Is done. The ECU 2 receives signals from the sensors 25, 26, 30 to 34, outputs a signal for controlling the fuel injection amount and the injection timing to the fuel injection valve 16, and ignites the spark plug 15. A timing control signal is output, a control signal for controlling the throttle opening degree is output to the actuator 24 of the throttle valve 23, and a signal for controlling the power generation amount to the regulator circuit 28a of the alternator 28. Output. The ECU 2 receives a signal from each of the sensors 25, 26, 30 to 40, and switches a switching signal for switching the source of the original pressure of the hydraulic control mechanism 63 between the oil pump 61 and the electric oil pump 62. A signal for adjusting the operating pressure of each of the friction elements 67 to 71 is output to the hydraulic control mechanism 63 (specifically, a solenoid valve included therein).

  Then, the ECU 2 automatically stops the fuel supply by stopping the fuel supply when a predetermined engine automatic stop condition is satisfied, and also during the automatic stop operation period of the engine or after the automatic stop of the engine, When a predetermined engine restart condition is established by operating an accelerator or a brake by the engine, the engine is automatically restarted by energy generated by combustion of the engine. In this embodiment, a plurality of the above automatic stop conditions are set, and the engine is automatically stopped when all these conditions are satisfied. On the other hand, a plurality of restart conditions are set, and the engine is automatically restarted when one or more conditions are satisfied according to the contents of the conditions.

  This engine restart will be described in detail. In the following description, a cylinder that is in the compression stroke when the engine is stopped is referred to as a compression stroke cylinder (or a compression stroke cylinder at the time of stop). These are referred to as an expansion stroke cylinder (or an expansion stroke cylinder when stopped), an intake stroke cylinder (or an intake stroke cylinder when stopped), and an exhaust stroke cylinder (or an exhaust stroke cylinder when stopped). For convenience of explanation, it is assumed that the cylinder 12A is an expansion stroke cylinder, the cylinder 12B is an exhaust stroke cylinder, the cylinder 12C is a compression stroke cylinder, and the cylinder 12D is an intake stroke cylinder.

  First, the first-time combustion is performed on the compression stroke cylinder 12C at the time of stop, the piston 13 is pushed down, the in-cylinder pressure is increased by the reverse operation of raising the piston 13 of the stop-time expansion stroke cylinder 12A, and then the expansion stroke cylinder. By injecting fuel into 12A to cause ignition and combustion, the combustion energy in the expansion stroke cylinder 12A at the time of stop is increased and the engine is restarted by ensuring the stroke of the expansion stroke cylinder 12A. The ECU 2 is configured.

  Thus, in order to restart the engine only with the combustion energy, it becomes a problem how to maximize the combustion energy in the expansion stroke cylinder 12A at the time of stop. For this purpose, the piston 13 is stopped when the engine is stopped. Must be stopped within a predetermined range to appropriately secure the amount of air for combustion in the stop-time compression stroke cylinder 12C and the stop-time expansion stroke cylinder 12A. Therefore, with reference to the expansion stroke cylinder 12A at the time of stop, a predetermined range slightly beyond the center of the stroke, that is, the position at which the crank angle after compression top dead center is 90 ° CA slightly toward the bottom dead center, for example, after compression top dead center. If the piston 13 can be stopped within a range where the crank angle is 100 ° to 120 ° CA, a predetermined amount of air is secured in the compression stroke cylinder 12C at the time of stop, and the engine is slightly reversed by the initial combustion. In addition, sufficient energy can be ensured by combustion in the stop-stroke expansion stroke cylinder 12A.

  There are various specific methods for controlling the stop position of the piston 13 during the automatic stop of the engine. Here, the compression of the expansion stroke cylinder 12A and the compression stroke cylinder 12C by air is controlled by controlling the opening degree of the throttle valve 23. While adjusting the force, the engine speed is finely adjusted through the resistance of the crankshaft 3 by controlling the power generation amount of the alternator 28 in the process of automatically stopping the engine, whereby the engine speed Ne is reduced after the fuel injection is stopped. The stop position of the piston 13 is controlled by being lowered along a reference line determined in advance by experiments or the like.

  Specifically, as shown in FIG. 10, the ECU 2 releases the friction elements 67 to 71 at a time T0 when the automatic engine stop condition is satisfied, thereby bringing the automatic transmission mechanism 50 into a drive state (here, D Switch from the range to the neutral state (N range here). Then, after the opening degree K of the throttle valve 23 is stabilized at 15%, at a time T1 when a predetermined time has elapsed, control is performed so that the engine speed Ne and the boost pressure Bt stop the piston 13 within a predetermined appropriate range. The fuel injection to each cylinder 12 is stopped when it is within a predetermined appropriate control range that can be properly executed. When the fuel injection is stopped at this time T1, the kinetic energy of the crankshaft 3 or the like is consumed due to mechanical loss due to frictional resistance or pumping work of each cylinder 12A to 12D, thereby causing the crankshaft 3 of the engine. The inertia is several revolutions, and in a 4-cylinder 4-cycle engine, it stops after reaching the compression top dead center of about 10 times.

  As described above, the stop position of the piston 13 is substantially determined by the balance of the compression reaction force in the stop-time compression stroke cylinder 12C and the stop-time expansion stroke cylinder 12A, and is influenced by the frictional resistance of the engine. It also changes depending on the rotational inertia of the engine at the time T4 when the compression top dead center is exceeded, that is, the level of the engine rotational speed Ne.

  Therefore, in order to stop the piston 13 of the expansion stroke cylinder 12A within the appropriate range suitable for restarting, first, the compression reaction forces of the expansion stroke cylinder 12A and the compression stroke cylinder 12C become sufficiently large, and the expansion stroke. It is necessary to adjust the intake air flow rates for the cylinders 12A and 12C so that the compression reaction force of the cylinder 12A is larger than the compression reaction force of the compression stroke cylinder 12C by a predetermined value or more.

  For this reason, in this embodiment, the expansion stroke cylinder 12A and the compression are set by setting the opening K of the throttle valve 23 to a large value (for example, about 30% of the opening when fully opened) at the fuel injection stop time T1. After a predetermined amount of air has been sucked into both the stroke cylinders 12C, at the time T2 when it has been confirmed that the engine rotational speed Ne has dropped below a preset reference speed N1 (for example, about 790 rpm), the throttle valve The intake air amount is adjusted by closing 23 and reducing the opening K.

  By the way, the fuel injection is stopped at the time T1 when the rotational speed Ne of the engine reaches a predetermined speed, and the cylinders of the engine that rotate due to inertia are maintained so as to keep the throttle valve 23 open for a predetermined period thereafter. When the top dead center rotational speed ne when the piston 13 provided in 12A to 12D passes through the compression top dead center is measured and the piston position of the expansion stroke cylinder 12A at the time of engine stop is examined, the engine is stopped. If the top dead center rotational speed ne at the sixth to second before is within a predetermined range as shown by hatching in FIG. 11, the stop position of the piston 13 is in a range suitable for engine restart ( It has been experimentally confirmed that it enters 100 ° to 120 ° CA after compression top dead center.

  Therefore, the ECU 2 sets the target generated current Ge of the alternator 28 at the fuel injection stop time T1, for example, to maintain the engine speed Ne at a speed at which the piston 13 can be controlled to stop within an appropriate range. The engine is set to 0, and at the time T2 when the engine speed Ne drops below the reference speed N1, the control is performed to increase the target generated current Ge of the alternator 28 to a preset initial value, and then the engine is rotated at the top dead center. At the time T3 when the speed ne falls within the predetermined range, the target power generation current Ge of the alternator 28 is decreased to a value corresponding to the decreased state of the engine rotational speed Ne to adjust the rotational resistance of the crankshaft 3, and the outside of the engine By changing the load according to the degree of decrease in the engine speed Ne, the load is changed to the reference line set based on experiments conducted in advance. And it is configured to reduce the engine rotational speed Ne me.

  Summarizing the control of the ECU 2 at the time of the automatic engine stop, the ECU 2 controls the opening of the throttle valve 23 when the engine is automatically stopped, and the air in the expansion stroke cylinder 12A and the compression stroke cylinder 12C when the engine is stopped. While adjusting the compression reaction force and controlling the amount of power generated by the alternator 28 during the automatic engine stop process, the engine rotation speed is finely adjusted through the resistance of the crankshaft 3. Ne is decreased along a reference line determined in advance by experiments or the like, and control is performed to stop the piston 13 within a predetermined appropriate range.

  Note that the piston 13 can be easily stopped in a predetermined range by switching the automatic transmission mechanism 50 to the N range at the time T0 when the automatic engine stop condition is satisfied. This is because the influence of vibration, reverse driving force and the like from the wheel side to the crankshaft 3 is suppressed. In particular, it is effective when performing control in which an automatic engine stop condition may be satisfied even when the vehicle is traveling (for example, during deceleration).

  As shown in FIG. 10, after the piston 13 is completely stopped at the time point T5, when the road surface inclination detected by the inclination sensor 40 is an uphill road having a predetermined value or more, the ECU 2 detects the automatic transmission mechanism 50. Is switched from the normal N range to the reverse prohibition N ′ range. By doing so, it is possible to prevent the vehicle from retreating at the time of the subsequent start while effectively suppressing the influence of the wheel 13 from affecting the stopped piston 13.

  Next, control during engine restart will be described. The ECU 2 is in the case where a predetermined restart condition (for example, brake OFF or the like) is satisfied for the engine that is in the automatic stop state as described above, and the piston 13 of the stop-time expansion stroke cylinder 12A is within a predetermined appropriate range. In this case, the in-cylinder pressure in the stop-time expansion stroke cylinder 12A is increased by executing the initial combustion in the stop-time compression stroke cylinder 12C to reversely operate the engine, and thus the in-cylinder pressure is increased. Then, control is performed so that the engine is automatically restarted by injecting fuel into the stop-time expansion stroke cylinder 12A to cause ignition and combustion.

  This engine restart control will be described with reference to the time charts of FIGS. The engine restart control is not limited to this, and may be other known restart control.

  As shown in FIGS. 12 and 13, first, the first fuel injection J2 is performed in the compression stroke cylinder 12C (third cylinder), and combustion ((1) in FIG. 12) is performed by the ignition. With the combustion pressure (part a in FIG. 13) due to this combustion (1), the piston 13 of the compression stroke cylinder 12C is pushed down to the bottom dead center side, and the engine is driven in the reverse direction.

  With the reverse rotation of the engine, the piston 13 of the stop expansion stroke cylinder 12A (first cylinder) starts to move in the direction of top dead center. The fuel injection J1 is performed when the piston 13 of the expansion stroke cylinder 12A moves to the top dead center side (preferably closer to the top dead center from the stroke center) and the air in the expansion stroke cylinder 12A is compressed. The compression pressure is reduced by the latent heat of vaporization of the injected fuel, and the piston 13 comes closer to the top dead center, so that the density of the compressed air (air mixture) increases (part b in FIG. 13).

  When the piston 13 of the expansion stroke cylinder 12A is sufficiently close to top dead center, the expansion stroke cylinder 12A is ignited, and the injected fuel (J1) is combusted ((2) in FIG. 12). The engine is driven in the forward direction by the combustion pressure (c portion in FIG. 13).

  In addition, fuel richer than the combustible air-fuel ratio is injected into the compression stroke cylinder 12C at an appropriate timing (J3) ((3) in FIG. 12), but the compression stroke cylinder 12C is not combusted, The compression pressure of the compression stroke cylinder 12C is reduced by the latent heat of vaporization caused by the fuel injection (part d in FIG. 12), and accordingly, the compression top dead center (the first compression top dead center from the start of starting) is exceeded. The initial combustion energy of the consumed expansion stroke cylinder 12A is reduced.

  Furthermore, the timing of fuel injection (J4) in the intake stroke cylinder 12D, which is the next combustion cylinder, is set to an appropriate timing ((4) in FIG. 12) for reducing the temperature in the cylinder and the compression pressure by the vaporization latent heat of the fuel. As shown, for example, since the middle of the compression stroke is set, self-ignition before the compression top dead center (T8) is prevented in the compression stroke of the intake stroke cylinder 12D. Further, in combination with the ignition timing of the intake stroke cylinder 12D being set after the compression top dead center, combustion before the compression top dead center is prevented (part e in FIG. 13). That is, by reducing the compression pressure by the fuel injection (J4) and not performing the combustion before the compression top dead center, the energy of the first combustion in the expansion stroke cylinder 12A becomes the compression top dead center (the second compression from the start of the engine start). It is possible to suppress consumption to exceed the top dead center.

  The compression top dead center (T8) in the compression stroke of the intake stroke cylinder 12D is the compression top dead center that reaches the second time after the engine restarts (the first top dead center is the compression stroke cylinder 12C). Hereinafter, the top dead center is also referred to as a second TDC.

  Thus, the first compression top dead center ((3) in FIG. 12) after the start of restart and the second compression by the energy of the first combustion ((2) in FIG. 12) in the expansion stroke cylinder 12A. It is possible to exceed the top dead center ((4) in FIG. 12), and a smooth and reliable startability can be ensured.

  Next, the operation of the automatic transmission mechanism 50 accompanying the engine restart will be described. When the engine is restarted on a normal flat road, the automatic transmission mechanism 50 is switched from the N range to the D range accordingly. For example, the forward clutch 67 is engaged and the D range first speed is set. As a result, the vehicle can re-start with the driver's accelerator operation. At that time, since it is desirable to quickly switch to the D range, for example, control for preliminarily supplying a hydraulic pressure to a state immediately before engagement to the friction elements 67 to 71 such as the forward clutch 67 (precharge control). Alternatively, rapid pressure increase control as disclosed in Patent Document 2 may be performed.

  On the other hand, if the above control is performed on the uphill road, the vehicle may move backward for a moment when the engine restart condition is satisfied by the driver releasing the brake. This is because the wheels can rotate in the reverse direction until the driving force of the engine increases to such an extent that it can resist gravity or until the transmission driving force of the automatic transmission mechanism 50 sufficiently increases. .

  Therefore, in this embodiment, the automatic transmission mechanism 50 is set to the reverse prohibition N ′ range on the uphill road. At least while the vehicle is in the reverse prohibition N ′ range, the rotation of the wheel in the reverse direction is restricted, so that the reverse of the vehicle is restricted even if the brake is released.

  FIG. 14 is a time chart showing the state of each part when the engine is restarted on an uphill road. Ne is the engine speed (reproduced simply from the engine speed shown in FIG. 13), TQ is the vehicle transmission torque, Ac is the accelerator opening, and K is the throttle opening.

  When the brake is released (ON → OFF) at time T6, the engine restart condition is satisfied. Thus, the engine restart control described with reference to FIGS. 12 to 13 is executed. At this time, the throttle opening K102 is corrected so as to be larger than the throttle opening K101 when the road surface is not inclined or the inclination St is less than the predetermined threshold value St1, that is, in the direction in which the intake flow rate increases. . Accordingly, the engine speed N102 and the vehicle transmission torque Q102 also increase from the engine speed N101 and the vehicle transmission torque Q101, respectively, when this correction is not performed. That is, a sufficient driving force for climbing up against gravity can be obtained.

  On the other hand, in the automatic transmission mechanism 50, the fastening operation of the forward clutch 67 is started from time T6. As described above, when the forward clutch 67 is engaged from the state of the reverse prohibition N ′ range, the automatic transmission mechanism 50 enters the second speed state (time T7). As described above, since the second speed is the reverse prohibition speed, the backward movement of the vehicle is restricted after time T7.

  After time T7, the driving force is transmitted in the second speed state, and the vehicle transmission torque increases as the generated torque of the engine increases (Q102). Here, in the present embodiment, the automatic transmission mechanism 50 is switched from the second speed to the first speed after the compression top dead center T8 (see FIG. 13) of the intake stroke cylinder 12D (time T9). Since the engine is surely restarted after time T8 and a high driving force is generated, it is no longer necessary to worry about reversing. Therefore, by switching to the first speed at which a larger driving force for climbing can be obtained, it is possible to start more smoothly.

  In addition, the above description respond | corresponds to the case of Ac102 whose accelerator opening Ac is comparatively small. In the present embodiment, when the accelerator opening degree Ac is relatively large (Ac103), the throttle opening degree is corrected until the time T10 at which the 2 → 1 shift is completed. That is, the throttle opening degree Ac103 is suppressed to about the throttle opening degree K102 corresponding to the accelerator opening degree Ac102. As a result, a 2 → 1 shift shock accompanied by a large change in driving force is alleviated, and passenger discomfort can be suppressed. After time T10, the throttle opening decrease correction is canceled, and the throttle opening K103 corresponding to the accelerator opening Ac103 is set. Accordingly, a high engine speed N103 and a large vehicle transmission torque Q103 can be obtained.

  FIG. 15 shows a schematic flowchart of automatic engine stop and restart control when the engine is automatically stopped on the road surface determined by the inclination sensor 40 to be an uphill road having a predetermined inclination or higher. When this control operation starts, it is first determined whether or not a fuel injection stop condition (hereinafter referred to as FC condition) is satisfied (step S1). This FC condition is a condition included in the automatic engine stop condition. For example, the FC condition is satisfied when the brake operation is ON and the vehicle speed is 10 km / h or less.

  If NO in step S1, the system waits until YES. If YES is determined, the engine automatic stop operation as described above is started and the automatic transmission mechanism 50 is switched to the N range (step S2). ). Then, after the engine is completely stopped (YES in step S3), the 2-4 brake 70 is engaged. In other words, the reverse prohibition N 'range is set (step S4).

  Then, when the brake operation is turned off (YES in step S5), the engine restart condition is satisfied, the restart operation is started, and the forward clutch 67 is started to be engaged (step S6). When the road surface slope St detected by the inclination sensor 40 is equal to or greater than the predetermined threshold value St1 (NO in step S7), correction for increasing the throttle opening K is performed (step S11). This makes it possible to obtain a large driving force that can start smoothly even on an uphill road with a high degree of inclination.

  Further, in step S12, it is determined whether or not the accelerator opening K is smaller than a predetermined threshold value K5. If NO in step S12, that is, if the accelerator opening is large, correction is made to decrease the throttle opening (step S15). As a result, it is possible to alleviate a shock at the time of the 2 → 1 shift performed later.

  Even if the determination is YES in step S7, the same determination and correction as in steps S12 and S15 are performed (steps S8 and S9).

  Furthermore, the engine waits for the engine to pass the compression top dead center (second TDC) of the intake stroke cylinder 12D at the time of stop (YES in step S20), and the 2-4 brake 70 is released (step S21). That is, a 2 → 1 shift with reduced shock is performed. Here, when the shift speed is set to the first speed, a larger starting driving force can be obtained. After the 2 → 1 shift, the correction made in step S9 or step S15 for reducing the throttle opening is canceled (step S22). As a result, a large driving force according to the accelerator opening can be obtained. Thereafter, the control shifts to the normal control of the engine and the automatic transmission mechanism 50 including the cancellation of the correction for increasing the throttle opening K made in step S11 (RETURN).

  As described above, the ECU 2 sets the automatic transmission mechanism 50 to the reverse prohibition N ′ range when the engine is automatically stopped on the road surface determined by the inclination sensor 40 to be an uphill road having a predetermined inclination or higher. Since control is performed to switch to the drive state at the time of restart, the automatic transmission mechanism 50 is set to the neutral state and the influence from the wheel side is effectively suppressed while the engine is automatically stopped under a predetermined condition so as to improve fuel efficiency. In addition, even if the automatic engine stop is executed on an uphill road, the backward movement of the vehicle can be regulated at the time of starting with engine restart without using a special slope starting assistance device.

  The engine starting device described above is an embodiment of the device to which the starting device according to the present invention is applied, and the specific configuration of the device is appropriately changed without departing from the gist of the present invention. This is possible, and modifications will be described below.

  (1) In the above embodiment, when the engine is restarted, the engine is once reversely rotated and then rotated forward, but may be restarted only by the forward rotation. However, once the engine is reversely operated, the combustion energy of the stop-stroke expansion stroke cylinder 12A increases, so that the engine can be restarted more reliably.

  (2) Although omitted in the above embodiment, when the engine is restarted and a predetermined condition is satisfied, for example, when the piston stop position is not within the predetermined proper range or within the proper range, the stop is performed. When the position is close to the boundary of the appropriate range, or when the engine rotation speed does not reach the predetermined value by the predetermined time after the start, and when the initial combustion of the engine is performed in the stop expansion stroke without further reverse rotation of the engine In addition, control with assist by a starter motor or the like (including a motor (ISG: Integrated Starter Generator) integrated with a starter and an alternator) may be performed. Even in this case, the burden on the starter motor can be reduced by the energy generated by the combustion of the engine. However, in this case, the fuel injection valve 16 may inject the fuel in the intake stroke so that vaporization and atomization of the injected fuel and mixing with the air proceed sufficiently directly into each cylinder. preferable.

  (3) In the above embodiment, the in-cylinder injection type is used as the fuel injection valve 16, but the present invention can also be applied to the case where a port injection type fuel injection valve is used.

  (4) In the above-described embodiment, the case where the automatic transmission mechanism 50 in which the reverse prohibition N ′ range and the reverse prohibition shift speed are obtained by engaging the 2-4 brake 70 has been described. The structure is not limited to the automatic transmission mechanism 50, and the friction elements to be fastened, the internal operation of the automatic transmission mechanism, and the like may be appropriately changed according to the basic structure of the automatic transmission mechanism. Further, the reverse prohibition speed is not limited to the second speed, and may be a speed higher than the third speed.

1 is a schematic cross-sectional view of an engine provided with a starter according to the present invention. It is explanatory drawing which shows the structure of the intake system and exhaust system of an engine. It is the schematic which shows an example of the automatic transmission mechanism in the starter which concerns on this invention. It is a relationship figure which shows the example of a relationship between the operating state of the friction element in the automatic transmission mechanism, and a gear stage. It is a schematic diagram which shows the driving force transmission path | route in the D range 1st speed of the automatic transmission mechanism, and the rotation direction of each part. It is a schematic diagram which shows the driving force transmission path | route in the D range 2nd speed of the automatic transmission mechanism, and the rotation direction of each part. It is a schematic diagram showing an example of a hydraulic control circuit of the automatic transmission mechanism. It is a relationship figure which shows the example of a relationship between the operating state of the solenoid valve in the automatic transmission mechanism, and a gear stage. It is a block diagram in the starting device concerning the present invention. It is a time chart which shows the change state of the engine speed at the time of an engine stop, change states, such as a throttle opening and a target electric power generation current. It is a distribution map which shows the correlation with the engine speed at the time of an engine stop, and a piston stop position. It is a time chart which shows the combustion operation etc. at the time of engine restart. It is a time chart which shows the change state etc. of the engine speed at the time of engine restart. It is a time chart which shows the state of each part in the case of performing engine restart on an uphill road. It is a flowchart which shows the control operation of an engine and an automatic transmission mechanism.

Explanation of symbols

1 Engine body 2 ECU (stop / restart control means)
3 Crankshaft 34 Accelerator sensor 38 Vehicle speed sensor 40 Inclination sensor (Inclination state detection means)
50 Automatic transmission mechanism 63 Hydraulic control mechanism

Claims (3)

When the automatic engine stop condition is satisfied, the fuel supply is stopped to stop the engine, and when the restart condition of the engine that is in the automatic stop state is satisfied, combustion is performed at least in the cylinder in the expansion stroke when the engine is stopped. An engine starter for a vehicle provided with stop / restart control means for automatically restarting the engine.
It is configured to switch between a drive state in which the driving force can be transmitted from the engine side to the wheel side and a neutral state in which the transmission of the driving force is disconnected, and in the neutral state, the wheel is moved backwards. An automatic transmission mechanism that can be in a neutral state that prohibits reverse rotation that restricts rotation;
Inclination state detection means for detecting the inclination state of the road surface,
The automatic transmission mechanism is configured such that at least one of the speed stages in the drive state, which is higher than the lowest speed stage, can be a reverse prohibition speed stage that restricts rotation of the wheels in the reverse direction.
The stop / restart control means sets the automatic speed change mechanism to the reverse prohibition neutral state when automatically stopping the engine on a road surface determined to be an uphill road having a predetermined inclination or more by the inclination state detection means, When the engine is restarted on the uphill road, the reverse-shifting-neutral state is switched from the reverse-prohibited neutral state to the low-speed stage via the reverse-prohibited shift stage, and the automatic transmission mechanism is changed from the reverse-prohibited shift stage to the lower speed stage. An engine starter for a vehicle, characterized in that the timing of switching is after the point in time when the cylinder in the intake stroke during the automatic engine stop exceeds the compression top dead center for the first time after engine restart .   It has an accelerator sensor that detects the accelerator opening,
  The stop / restart control means corrects the intake flow rate in a direction to decrease until the shift speed change of the automatic transmission mechanism is completed when the accelerator opening at the time of engine restart is a predetermined value or more. The vehicle engine starting device according to claim 1.   The stop / restart control means corrects the intake air flow rate to increase in a predetermined period in the engine restart process when the slope of the road surface detected by the inclination state detection means is equal to or greater than a predetermined value. The engine starter for a vehicle according to claim 1 or 2, characterized in that

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