JP4356227B2 - Engine starter and engine system having the function - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
  The present invention relates to an engine starter that starts an engine by driving the engine through an endless member by a motor, and particularly relates to detection of an abnormality of the endless member. The endless member is, for example, a belt or a chain, and is a long and flexible ring-shaped power transmission member. Here, the present invention will be described mainly by taking up a belt (belt-driven starter) as one form of an endless member.
[0002]
[Prior art]
  In an engine starter driven by a belt (endless member), a starter motor is connected to the engine via a belt as disclosed in, for example, Japanese Patent Application Laid-Open No. 11-147424. Then, the rotational force of the starting motor is transmitted to the engine via this belt, and the engine is cranked and started.
[0003]
  The belt-driven starter has no gear noise and can start the engine smoothly as compared with a conventional gear mesh starter motor. This advantage has attracted attention and is being developed in hybrid vehicles and eco-run (idling stop) vehicles that repeatedly start and stop the engine.
[0004]
  In this type of starting device, a V-ribbed belt similar to that used in conventional driving of accessories can be used as the power transmission belt. Further, it is also preferable to wind a single belt around the engine, the starting motor and the auxiliary machine. This is a so-called serpentine layout. This configuration is also disclosed in Japanese Patent Application Laid-Open No. 11-147424, and the auxiliary machine is driven by the output of the engine or motor. Typical auxiliary machines are a water pump, an air conditioner, and a power steering pump.
[0005]
[Problems to be solved by the invention]
  However, the load applied to the belt when starting the engine is as large as several times to several tens of times the load when the auxiliary machine is driven. If the belt is abnormal due to this high load, such as cutting or significant wear, power transmission for starting the engine may be disabled. Nevertheless, until now, it has been common to use a conventional belt system for driving auxiliary equipment as it is. For this reason, it has not been particularly considered to detect the occurrence of a belt abnormality due to a high load or to ensure a fail-safe function for the belt abnormality.
[0006]
  A similar problem may occur when an endless member other than a belt, such as a chain, is used. The belt abnormality is slipping and disconnection (cutting), while the chain abnormality is mainly disconnection.
[0007]
  The present invention has been made in view of the above problems, and an object of the present invention is to provide an engine starter that can appropriately detect an endless member abnormality (belt abnormality). Another object of the present invention is to provide an engine starter having an appropriate fail-safe function when an abnormality occurs.
[0008]
[Means for Solving the Problems]
[0009]
[0010]
[0011]
[0012]
[0013]
[0014]
[0015]
[0016]
[0017]
[0018]
[0019]
[0020]
[0021]
[0022]
[0023]
  An engine starter according to the present invention is an engine starter that starts by driving an engine through an endless member such as a belt or a chain by a motor. When an abnormality of the endless member is detected, the engine starter An engine starter characterized in that the engine is started using another motor that has been used as a failsafe starter motor.Thereby, even when the abnormality of the endless member occurs, the engine starting ability can be ensured.
[0024]
  An engine system according to the present invention is wound around an engine, a motor for driving and starting the engine, a mechanical water pump for cooling the engine, the engine, the motor, and the mechanical water pump. In an engine system including an endless member such as a power transmission belt or chain, an abnormality detecting means for detecting that an abnormality has occurred in the endless member, and when an abnormality has occurred in the endless member, An engine system comprising: an abnormality handling processing means for operating an electric water pump provided separately from a mechanical water pump as a failsail pump.
[0025]
  This configurationIn this system, when an endless member is abnormal, the mechanical water pump does not operate normally. According to the present invention, by operating the electric water pump as a fail-sale pump, at least a part of the cooling capacity that has been lowered due to an abnormal operation of the mechanical water pump can be compensated.
[0026]
  The present inventionAccording to another aspect of the present invention, there is provided an engine starter for starting an engine by driving the engine through an endless member such as a belt or a chain by a motor, and an inertia estimation means for estimating the inertia from the rotational speed of the motor and the motor acceleration, And an abnormality determining means for determining that an abnormality has occurred in the endless member when the value is equal to or less than a predetermined value.
[0027]
  Further, in an engine starter that starts an engine by driving the engine through an endless member such as a belt or a chain by a motor, inertia estimation means for estimating the inertia from the rotational speed of the motor and the motor acceleration, and the inertia is a predetermined reference Torque command value control means for appropriately controlling the torque command value to the motor so as to be larger than the value, and determining that an abnormality has occurred in the endless member when the torque command value falls below a predetermined threshold torque command value And an abnormality determining means.
[0028]
  According to this aspect, the inertia of the motor is examined, and thereby the abnormality of the endless member can be detected. Further, the torque command value for the motor controlled so that the inertia of the motor becomes larger than a predetermined reference value is checked, and the abnormality of the endless member can be detected by this. And it can aim at fail safe using this abnormal appearance result.
[0029]
  As described above, according to the present invention, an abnormality of an endless member can be detected, and a fail-safe function can be added by taking measures against the abnormality of the endless member based on the detection result. The reliability of the system can be improved.
[0030]
[0031]
DETAILED DESCRIPTION OF THE INVENTION
  DESCRIPTION OF EXEMPLARY EMBODIMENTS Hereinafter, preferred embodiments (hereinafter referred to as embodiments) of the invention will be described with reference to the drawings.
[0032]
  Embodiment 1. FIG.
  In the present embodiment, as an example, the engine starter of the present invention is applied to a hybrid vehicle. However, the application target of the present invention is not limited to a hybrid vehicle. For example, the present invention can be suitably applied to an eco-run vehicle.
[0033]
  In the present embodiment, the endless member is a belt, but the present invention is not limited to this. The endless member may be a chain, for example. The endless member is a power transmission member that transmits power for starting the engine from the motor to the engine, and is a flexible ring-shaped member.
[0034]
  FIG. 1 shows an example of a hybrid system. As is well known, a hybrid system is a system that drives a vehicle using both an engine and a motor generator (electric motor). In the system of FIG. 1, an engine 1, a main motor generator 3, a planetary gear unit 5, and a continuously variable transmission (CVT) 7 are sequentially arranged, and an output shaft of the continuously variable transmission 7 is connected to drive wheels. . The engine 1, the main motor generator 3, and the continuously variable transmission 7 are connected to the sun gear, the planetary gear, and the ring gear of the planetary gear unit 5, respectively. By adjusting the rotation speed and output of the engine 1 and the main motor generator 3, a desired rotation speed and output are given to the input shaft of the continuously variable transmission 7.
[0035]
  A starter motor 9 and an auxiliary machine 11 are attached to the engine 1. Although only one auxiliary machine is visible in FIG. 1, two auxiliary machines, a water pump and an air conditioner, are actually installed. However, the present invention is not limited to the type and number of auxiliary machines.
[0036]
  The engine 1, the starter motor 9, and the auxiliary machine 11 are connected via a power transmission belt 13 (an endless member). Specifically, a crank pulley 15 is attached to the crankshaft of the engine 1 on the side opposite to the output side. Pulleys 17 and 19 are also attached to the starter motor 9 and the auxiliary machine 11, respectively. Belts 13 are wound around these pulleys. As the belt 13, a conventional V-ribbed belt for driving auxiliary equipment can be used. Other,Continuously variable transmission 7Is attached with an oil pump 7a, which is driven by an oil pump A / C motor 7b.
[0037]
  FIG. 2 is a view of the engine 1 as viewed from the crank pulley side, and shows a belt layout. A belt 13 is wound around a crank pulley 15, a starter motor pulley 17, and a water pump pulley 19a and an air conditioner pulley 19b as auxiliary pulleys. An idler 21 is provided between the crank pulley 15 and the starter motor pulley 17 in order to increase the belt winding angle and transmit a large driving force. An auto tensioner 23 is provided between the starter motor pulley 17 and the water pump pulley 19 to give a constant tension to the belt 13.
[0038]
  In the above system, at the start of operation, when the driver turns the ignition key, the motor generator 3 rotates, the rotational force is transmitted to the engine 1, and the engine 1 is cranked and started.
[0039]
  After the operation is started, the operation state of the engine 1 and the motor generator 3 is controlled so that high fuel efficiency is obtained, and the energy efficient operation is performed. For example, when the amount of power stored in the in-vehicle battery is sufficiently large, the engine 1 is stopped. Then, the vehicle is driven using only the output of motor generator 3, and therefore the vehicle travels as a pure electric vehicle.
[0040]
  While the engine 1 is stopped, the auxiliary machines (water pump and air conditioner) can be driven by the starter motor 9. In this mode, it is preferable to disconnect the crank pulley of the engine 1 from the crankshaft, thereby reducing energy loss. In the above-mentioned Japanese Patent Application Laid-Open No. 11-147424, the crank pulley is separated using a clutch.
[0041]
  Thereafter, when the storage amount of the battery decreases, the engine 1 is restarted. Also at this time, the engine 1 is cranked by the output of the starter motor 9. Then, the motor generator 3 generates electric power using the engine output, and the battery is charged using this generated electric power.
[0042]
  Thus, in the hybrid vehicle, the engine 1 is repeatedly stopped and started during operation, and therefore, a belt-driven starter (endless member-driven starter) is suitable. This is because, compared with a conventional gear meshing starter motor, there is no gear noise and the engine can be started smoothly.
[0043]
  However, the load applied to the belt when starting the engine is as large as several times to several tens of times the load when the auxiliary machine is driven. If a belt abnormality such as cutting or significant wear occurs due to a high load, power transmission for starting the engine may be disabled. Therefore, the present invention detects a belt abnormality as follows.
[0044]
  FIG. 3 shows a functional block diagram corresponding to the system of FIG. The engine 1, the main motor generator 3, and the starter motor 9 are controlled by the ECU 30. The engine speed sensor 32 detects a signal indicating the engine speed Ne and outputs it to the ECU 30. The starter motor rotation sensor 34 detects a signal indicating the rotation speed Nm of the starter motor and outputs it to the engine ECU 30.
[0045]
  The ECU 30 is provided with a belt abnormality detection unit 36 and an abnormality response processing unit 38. That is, in this embodiment, the belt abnormality detection device is provided as a partial function of the ECU 30.
[0046]
  From the viewpoint of hardware, the ECU 30 may be composed of a plurality of individual ECUs. For example, a configuration is known in which an engine ECU, a motor ECU, and a hybrid ECU that controls them from above are provided. The belt abnormality detection function may be provided in any ECU, and a plurality of ECUs may jointly perform the belt abnormality detection function of the present invention. Furthermore, the belt abnormality detection device may be provided independently of these ECUs.
[0047]
  FIG. 4 shows a control process at the time of starting the engine by the ECU 30 including the belt abnormality detecting unit 36 and the abnormality handling processing unit 38 of FIG. After stopping the engine, wait for the start request to turn on. When the start request is turned on, the starter motor is turned on, the engine is cranked by the starter motor (S10), and the rotation speed Nm and the engine rotation speed Ne of the starter motor are detected (S12).
[0048]
  And the motor rotation speed Nm andMultiplied by pulley ratioEngine speed NeTogaIt is compared, and it is determined whether or not the rotational speed difference between them is larger than a predetermined threshold rotational speed difference N (S14). Here, as shown in FIG. 4, it is determined whether or not Nm−αNe> N (α is a pulley ratio or the like). The threshold speed difference N is, for example, 100 rpm. The determination timing is set after a predetermined time (for example, about 0.6 seconds) has elapsed since the starter motor was turned on. The determination timing and the threshold rotational speed difference are set in advance and stored in the ECU. These appropriate settings will be described in more detail later.
[0049]
  If S14 is NO, it is determined in S16 that there is no belt abnormality. The engine start is continued as it is, and the engine start is successful. On the other hand, when S14 is YES, it is considered that a belt abnormality has occurred. This is because the rotation of the motor is not properly transmitted to the engine. Therefore, the process proceeds to S18, where it is determined that there is an abnormality, and the process immediately proceeds to the abnormality handling process of S20 and S22.
[0050]
  As an abnormality handling process, the starter motor is turned off (S20), and the engine is started using the main motor generator (S22). Here, the motor generator is used as a fail-safe motor, thereby ensuring the startability of the engine.
[0051]
  Furthermore, it is preferable to notify the driver of the belt abnormality as the abnormality handling process. Abnormality notification can be made with a warning sound or synthesized voice using a speaker. The abnormality report can also be made visually using a display lamp, a display, or the like. At this time, it is also preferable to instruct the driver to move to a safe place or stop.
[0052]
  Furthermore, it is also preferable to communicate the occurrence of an abnormality to the outside using in-vehicle communication means. As the communication device, for example, an ITS (Intelligent Transport Systems) related communication device or a Mayday notification device can be used.
[0053]
  As described above, according to the present embodiment, belt abnormality can be detected, and fail-safe treatment based on the abnormality detection result can be performed. Even if a belt abnormality occurs, engine startability can be ensured, and road faults, that is, the vehicle can be prevented from getting stuck on the road. Further, by detecting the abnormal slip of the belt, it is possible to reduce the belt damage and extend the life.
[0054]
  Further, according to the present embodiment, the belt abnormality can be detected by using existing sensors such as an engine rotation sensor and a motor rotation sensor. Therefore, it is not necessary to attach a new sensor, and it is possible to detect an abnormality in the belt at a low cost without causing a complicated configuration.
[0055]
  In the present embodiment, the present invention is applied to a hybrid vehicle. However, as described above, the application target of the present invention is not limited to a hybrid vehicle, and the present invention can be suitably applied to, for example, an eco-run vehicle.
[0056]
  One form of the eco-run vehicle is called MG eco-run, and a motor generator for eco-run is connected to the engine via a belt. When the engine is started, the motor generator for eco-run functions as a motor and cranks the engine. After the engine is started (during rotation), the eco-run motor generator functions as an alternator, rotates at the output of the engine to generate electric power, and charges the auxiliary battery. Even in such a system, the belt abnormality detection of the present invention is similarly applied.
[0057]
  In the above MG eco-run system, it is preferable to provide an auxiliary starter motor separately from the starter motor connected by a belt for the purpose of ensuring low temperature startability. As this auxiliary starter motor, a conventional gear meshing starter motor can be used. When an abnormality in the belt is detected, it is preferable to start the engine using the auxiliary starter motor for fail safe.
[0058]
  Next, with reference to FIG. 5, the setting of “threshold speed difference for determination” and “determination timing” in the above-described abnormality detection will be described. FIG. 5 shows how the motor rotation speed Nm and the engine rotation speed Ne increase after the starter motor is turned on when there is an abnormality in the belt.
[0059]
  When a belt is used for the engine starting device, a severe belt abnormality that deteriorates the engine starting performance such as belt breakage or significant wear becomes a particular problem. When such a belt abnormality occurs, as shown in FIG. 5, a large rotational speed difference appears considerably early after the starter motor is turned on. As a reference, in contrast to this, if there is no slip or abnormality in the belt, the rotational speed difference is almost zero. In addition, even when a slight abnormality such as a slight slip of the belt occurs, the rotational speed difference is small, and a significant rotational speed difference appears after a certain amount of time has passed since the starter was turned on.
[0060]
[0061]
  For judgment in abnormality detectionThe “threshold rotational speed difference” is an appropriate value between the rotational speed difference in the abnormal state and the rotational speed difference in the normal state (generally almost 0), and is based on the rotational speed difference in the abnormal state. Set to a value somewhat smaller than that.
[0062]
  Furthermore, in this embodiment, as shown in FIG. 5, it is considered that there is an unstable transition period in which the rotational speed difference is unstable immediately after the starter is turned on. In this transition period, the difference between the rotation speeds of the motor and the engine does not appear as theoretically, and even if the belt is normal, a difference in the rotation speeds may occur. Therefore, the “determination timing” is set at the time when the transition period has passed, so that the belt abnormality can be reliably detected.
[0063]
  As a result of the above setting, in the example of FIG. 5, the determination timing t0 is set when about 0.6 seconds have elapsed from the starter on, and the threshold rotation speed difference is set to about 100 rpm.
[0064]
  As described above, according to this embodiment, the belt abnormality that causes a problem in starting the engine can be reliably detected at an early stage by appropriately setting the determination timing and the reference value for determination. This type of abnormality detection has not been required when a V-ribbed belt is used for conventional accessory driving, and thus has not been found in a starting system that simply uses the accessory driving belt specification. And this embodiment can also implement a fail safe countermeasure and abnormality response processing at an early stage by early abnormality detection after a starter is turned on, and can immediately eliminate the state where the engine cannot be stopped.
[0065]
  Reference example.
  Next, referring to FIG. 6 and FIG.Reference exampleThe belt-driven starter will be described. BookReference exampleBut the hybrid system in Figure 1Apply to. But bookReference exampleThen, the belt abnormality is detected based on a phenomenon different from the above-described embodiment.
[0066]
  BookReference exampleThen, as shown in the belt layout of FIG. 2, one belt is wound around an auxiliary machine as a vehicle device in addition to the engine and the starter motor. Utilizing this fact, an operational abnormality of the vehicle device around which the belt is wound is detected, and when this operational abnormality is detected, it is determined that the belt abnormality has occurred. This is because it can be estimated that the cause of the abnormal operation is that the power transmission of the belt is not normal. Specifically, bookReference exampleThen, as described below, the belt abnormality is detected based on the operating state of the water pump.
[0067]
  FIG. 6 is a diagram corresponding to FIG. 3 of the first embodiment, and FIG.Reference exampleA hybrid system is shown focusing on the configuration related to belt abnormality detection. The engine 1, the main motor generator 3, and the starter motor 9 are controlled by the ECU 40. The engine water temperature sensor 42 detects a signal indicating the temperature THW of the engine cooling water and outputs it to the ECU 40. The throttle sensor 44 detects a signal indicating the opening degree TA of the throttle provided in the intake passage and outputs it to the ECU 40. An accelerator operation amount may be used as the throttle opening. The ECU 40 further controls the electric fan 46 of the radiator, and can know whether the electric fan 46 is operating or stopped.
[0068]
  The ECU 40 is provided with a belt abnormality detection unit 48 and an abnormality response processing unit 50. Book like thisReference exampleHowever, as in the first embodiment, the belt abnormality detection device is provided in the form of a partial function of the ECU 40. As in the first embodiment, the ECU 40 may be composed of a plurality of individual ECUs, and any ECU may be provided with a belt abnormality detection function.
[0069]
  FIG. 7 shows belt abnormality detection processing by the belt abnormality detection unit 48 of FIG. After the engine is started, the abnormality detection unit 48 monitors the engine water temperature THW and determines whether or not the threshold water temperature T0 for determination has been exceeded (S30).
[0070]
  When S30 becomes YES, the engine cooling water pump may not be operating. The reason why the water pump has stopped is considered to be a belt abnormality. This is because if an abnormality such as belt breakage or wear occurs, the rotational force is not transmitted to the water pump.
[0071]
  However, even if the water pump is normal, the engine water temperature may rise due to another cause. Therefore, in S32 to S36, it is confirmed whether or not the engine water temperature is rising due to a cause other than the water pump.
[0072]
  If S30 is YES, it is determined in S32 whether or not the throttle opening TA has exceeded a threshold opening TA0 for determination. When S32 is YES, it progresses to S34 and it determines with the cause of a water temperature rise being overload driving | running | working.
[0073]
  When S32 is NO, it progresses to S36 and it is determined whether the electric fan of a radiator is operating. If the electric fan has stopped, it will progress to S38 and will determine that the cause of the water temperature rise is an abnormality of the electric fan.
[0074]
  If the electric fan is in operation in S36, the process proceeds to S40 and it is determined that a belt abnormality has occurred. Since the cause of the water temperature increase is not overload running and the electric fan is not abnormal, it can be estimated that the water temperature has increased because the water pump has stopped due to the belt abnormality.
[0075]
  When a belt abnormality is detected, the abnormality response processing unit 50 of the ECU 40 prohibits the use of the starter motor for the next engine start. Then, in the next engine start, the main motor generator is used to instruct the engine to start. As a result, the motor generator is used as a fail-safe motor, and engine startability can be ensured.
[0076]
  Further, as described in the first embodiment, as the abnormality handling process, it is preferable to notify the driver of the occurrence of abnormality or notify the occurrence of abnormality to an information center outside the vehicle using communication means.
[0077]
  As explained above, the bookReference exampleAccording to the invention, it is possible to detect the belt abnormality by detecting the operation abnormality of the vehicle device around which the belt is wound while the engine is operating. Specifically, by monitoring the engine water temperature, it is possible to detect an abnormal operation of the water pump and detect a belt abnormality. Even if a belt abnormality occurs, engine startability can be ensured.
[0078]
  Also bookReference exampleIn the abnormality detection process, it is confirmed whether or not the engine is operating at a high load. Then, it is determined that a belt abnormality has occurred when the engine water temperature has risen to a predetermined value or higher, even though the engine is not operating at a high load. Specifically, it is confirmed that the throttle opening is not more than a predetermined threshold opening. Therefore, it is possible to prevent erroneous determination that a belt abnormality has occurred when the engine water temperature rises due to high load operation on an uphill road.
[0079]
  More booksReference exampleThen, in the abnormality detection process, it is confirmed whether or not the radiator system is operating normally. Then, it is determined that a belt abnormality has occurred when the engine water temperature rises to a predetermined value or higher despite the radiator system operating normally. Specifically, it is confirmed that the electric fan of the radiator is operating. Accordingly, it is possible to prevent erroneous determination that a belt abnormality has occurred when the engine water temperature rises due to a radiator abnormality.
[0080]
  Like thisReference exampleThen, it is confirmed whether or not the engine water temperature has increased due to a cause other than the belt abnormality, and therefore it is possible to more reliably detect the belt abnormality.
[0081]
  Also bookReference exampleThen, the belt abnormality can be detected using an existing sensor such as an engine water temperature sensor. Therefore, it is not necessary to attach a new sensor, and it is possible to detect an abnormality in the belt at a low cost without causing a complicated configuration.
[0082]
  BookReference exampleThen, the engine water temperature itself is directly detected using the engine water temperature sensor. However, another temperature indicating the level of the engine water temperature may be used as the engine water temperature. For example, the ambient temperature in the engine room may be used. like thisAnotherWhen the temperature (indirectly indicating the engine water temperature) is high, it is determined that the belt abnormality has occurred, assuming that the engine water temperature has exceeded the specified value.To do.
[0083]
  Also bookReference exampleThenhybridApplied to the vehicle. However, as described in the first embodiment,Reference exampleIs not limited to hybrid vehicles, for example, eco-run vehicles (including the above-mentioned MG eco-run vehicles)SuitablyApplicable.
[0084]
  Embodiment 2. FIG.
  Next, the present inventionSecond embodimentWill be described. This embodimentIn 2The engine system is provided with a further fail-safe function against belt abnormality.
[0085]
  In the belt layout shown in FIG. 2, the belt is wound around the engine, the starter motor, and the water pump. A water pump is a mechanical water pump driven by the rotational force of an engine or a motor.
[0086]
  Therefore, when a belt abnormality such as a belt cut occurs, cooling by the water pump becomes impossible, or the cooling capacity is greatly reduced, and overheating is caused when the engine operation is continued. In this case, it is conceivable that the vehicle travels as a pure electric vehicle using only the motor generator. Or it is possible to drive | work using an engine until it overheats. However, these evacuation runs can only be continued for a relatively short time and distance, and the evacuation travel distance cannot be extended.
[0087]
  In view of the above-described circumstances, the present embodiment provides a system that can perform a more favorable evacuation traveling when the belt is abnormal from a fail-safe viewpoint. In order to achieve this object, in this embodiment, when a belt abnormality occurs, an electric water pump provided separately from the mechanical water pump is used without depending on the mechanical water pump around which the belt is wound. Operates as a failsail pump. As a specific example, an electric pump provided to ensure heater performance when idling is stopped is used. As a result, the cooling capacity can be supplemented, and the reach of the evacuation travel can be increased. Hereinafter, a specific example of this embodiment will be described with reference to FIGS.
[0088]
  FIG. 8 shows the engine constituting the hybrid system of FIG. 1 with its cooling system as the center. The mechanical water pump 11 a is attached to the cylinder block end face of the engine 1. As described with reference to FIGS. 1 and 2, the rotational force of the engine 1 or the starter motor (not shown) is transmitted to the mechanical water pump 11a via the belt 13, and the pump 11a operates.
[0089]
  The mechanical water pump 11a operates to push cooling water from the engine inlet 60 into the engine. The cooling water exits from the engine outlet 62 through the engine and flows into the cooling water passage 64. The cooling water passage 64 is divided into a radiator passage 66 and a heater passage 68.
[0090]
  The radiator passage 66 returns to the engine inlet 60 through the radiator 70. When passing through the radiator 70, the cooling water is cooled. The heater passage 68 returns to the engine inlet 60 through the heater core 72. In the heater core 72, the air blown into the vehicle interior is warmed by the heat of the cooling water.
[0091]
  The radiator passage 66 and the heater passage 68 merge before the engine inlet 60. A bypass passage 73 is also provided from the vicinity of the engine outlet 62, and merges with the radiator passage 66 before the engine inlet 60. A thermostat 74 is provided in this portion, and the distribution of the coolant flow rate in the radiator passage 66 and the bypass passage 73 is adjusted.
[0092]
  An electric water pump 76 is installed in the heater passage 68 on the upstream side of the heater core 72. Originally, the electric water pump 76 is provided in order to ensure the heater performance when idling is stopped, as will be described below.
[0093]
  In the hybrid vehicle, the engine 1 is repeatedly stopped and started. When the engine 1 is stopped, the mechanical water pump 11a is stopped and the circulation of the cooling water is also stopped. Therefore, the supply of cooling water to the heater core 72 is stopped, and the air passing through the heater core 72 cannot be warmed, resulting in a deterioration of the heater function. Therefore, an electric water pump 76 is provided to ensure the heater function. While the engine is stopped, the electric water pump 76 is used to circulate cooling water.
[0094]
  The operation of the electric water pump 76 is also controlled by the ECU (FIGS. 3 and 6). In the present embodiment, as will be described below, the heater electric water pump 76 is utilized for a retreat travel when the belt is abnormal. That is, when an abnormality such as cutting occurs in the belt 13, the mechanical water pump 11a does not operate normally. Therefore, the electric water pump 76 is operated to supplement the cooling performance.
[0095]
  FIG. 9 is a flowchart showing the saving traveling process of the present embodiment, and this process is preferably executed by an ECU as shown in FIGS. 3 and 6.
[0096]
  In FIG. 9, a belt abnormality is detected in S50. The detection of the belt abnormality is the above-described first embodiment (using the difference between the motor and engine speed)According toIt is preferred to do so. However, the belt abnormality may be detected by other methods, and this case is also included in the scope of the present embodiment.
[0097]
  When the belt abnormality is detected, the engine is stopped (S52) and the electric vehicle is run (S54). Here, the vehicle travels as a pure electric vehicle using only the motor generator.
[0098]
  In S56, the battery SOC is checked. If the SOC is OK, the electric vehicle travels. The SOC (State Of Charge) is a parameter indicating the storage state of the battery, and is represented by, for example, a ratio of the current storage amount to the full storage amount.
[0099]
  The SOC becomes NG in S56 when the storage amount of the battery is reduced to some extent. In this case, the engine is started in S58. Here, cranking is performed using the main motor generator instead of the starter motor in accordance with the fail-safe function described above.
[0100]
  As described above, the engine can be started even if a belt abnormality occurs using the main motor generator. However, the mechanical water pump cannot be operated normally after the engine is started. This reduces the cooling capacity and immediately overheats.
[0101]
  In order to avoid overheating, the electric water pump for heaters is operated in S60 as a feature of this embodiment. The flow rate of the electric water pump is controlled so that the cooling capacity becomes appropriate while checking the engine water temperature, the battery SOC, and the engine speed. Then, the electric vehicle travel is stopped and the vehicle travels using the engine output (S62).
[0102]
  When engine running is started, the engine water temperature obtained from the engine water temperature sensor is monitored (S64). If the engine water temperature has not reached a predetermined value (a preset overheat determination threshold), the determination in S64 is OK, and the battery SOC is checked in S68. While the engine is running, the motor generator generates power using the engine output, and the battery is charged. When the battery is sufficiently charged, the determination in S68 is OK. In this case, it returns to S52, stops an engine, and returns to electric vehicle driving | running | working.
[0103]
  If the SOC is NG in S68, the battery is not sufficiently charged, so the process returns to S62 and the engine running and the battery charging are continued. In S64, when the engine water temperature is equal to or higher than a predetermined value, the determination result is NG. In this case, it is determined as overheating, the engine is stopped, and the vehicle is stopped (S66). Preferably, the driver is notified that the vehicle will stop, and the driver stops the vehicle at an appropriate location.
[0104]
  As described above, in this embodiment, the heater water heater is operated to compensate for the cooling performance lost due to the belt abnormality, so that the engine water temperature rise can be slowed down. Accordingly, overheating can be prevented, or the traveling time and traveling distance of the evacuation traveling until overheating can be achieved.
[0105]
  Similarly to the other embodiments described above, this embodiment can also be applied to vehicles other than hybrid vehicles. For example, the present invention can also be suitably applied to eco-run vehicles (including the above-described MG eco-run vehicles).
[0106]
  Embodiment 3. FIG.
  FIG. 10 shows a functional block diagram of an engine starter corresponding to the hybrid system according to the present invention shown in FIG. 10, the same components as those in the functional block diagram shown in FIG. 3 are denoted by the same reference numerals, and the description thereof is omitted.
[0107]
  10, in addition to the belt abnormality detection unit 36 and the abnormality handling processing unit 38 shown in FIG. 3, the ECU 30 includes an inertia estimation unit 80 for estimating the inertia of the starter motor 9 and a starter corresponding to the estimated value of this inertia. A torque command value control unit 82 that controls a torque command value applied to the motor 9 is provided.
[0108]
  As described with reference to FIG. 3, the ECU 30 may be composed of a plurality of individual ECUs from the viewpoint of hardware.
[0109]
  The inertia estimation unit 80 converts the rotation speed Nm after conversion of the pulley ratio of the starter motor 9 detected by the motor rotation sensor 34 into acceleration of the starter motor 9, and calculates the inertia of the starter motor 9 therefrom. The inertia can be estimated by a method such as using an observer.
[0110]
  In general, if a slip occurs between the belt 13 and the starter motor 9 and the pulley of the engine 1, the inertia of the starter motor 9 is reduced. Therefore, when the inertia estimated by the inertia estimation unit 80 is equal to or less than a predetermined reference value, the belt abnormality detection unit 36 determines that the belt 13 has slipped and the belt 13 is abnormal. When it is determined that the belt is abnormal, the abnormality handling processing unit 38 performs the abnormality handling processing as described in the first embodiment.
[0111]
  In this case, the torque command value control unit 82 performs a process of reducing the torque command value applied to the starter motor 9. This is because the slip of the belt 13 can be suppressed if the torque of the starter motor 9 is reduced.
[0112]
  Further, as described above, the torque command value to the starter motor 9 determined by the torque command value control unit 82 is monitored, and a belt abnormality occurs when this value falls below a predetermined threshold torque command value. It is also possible to employ a configuration in which the effect belt abnormality detection unit 36 detects the effect. As described above, when slip occurs in the belt 13, the torque command value is reduced by the torque command value reduction process.
[0113]
  FIG. 11 shows a process when the torque command value reduction process is performed when the inertia of the starter motor 9 is smaller than a predetermined reference value in the engine starter according to the present embodiment shown in FIG. In FIG. 11, the rotation speed of the starter motor 9 is calculated by the motor rotation sensor 34 (S1), and the rotation speed Nm of the starter motor 9 converted to the pulley ratio is calculated from this value (S2). The inertia estimation unit 80 calculates the acceleration of the starter motor 9 from the rotation speed Nm after the pulley conversion of the starter motor 9 (S3), and estimates the inertia of the starter motor 9 using the observer as described above (S4). ).
[0114]
  Next, it is determined whether or not the estimated inertia is larger than a predetermined reference value (S5). If the inertia is smaller than the reference value, the belt abnormality detection unit 36 determines that the belt is abnormal, and the torque command value. The controller 82 performs a process of reducing the torque command value given to the starter motor 9 (S6).
[0115]
  As described above, when slip occurs between the belt 13 and the pulley and the inertia of the starter motor 9 becomes smaller than a predetermined reference value, the torque command value applied to the starter motor 9 is decreased, and the slip Is controlled so that the starter motor 9 is operated in a slip-free state, that is, in a state where the inertia is larger than a predetermined reference value.
[0116]
  12A, 12B, and 12C show how the estimated inertia value of the starter motor 9 changes over time. FIG. 12A shows the state of the estimated inertia value of the starter motor 9 when the starter motor 9 and the pulley of the engine 1 and the belt 13 are not slipping. In this case, the engine crankshaft and the starter motor 9 are coupled via a belt or an electromagnetic clutch, and the inertia of the starter motor 9 is larger than a predetermined reference value.
[0117]
  On the other hand, FIG. 12B shows an example in which the belt 13 slips and the inertia of the engine 1 is not added. In this case, the estimated inertia value of the starter motor 9 is lower than the reference value.
[0118]
  As described above, when slip occurs in the belt 13, the torque command value control unit 82 reduces the torque command value applied to the starter motor 9 and suppresses the slip, as shown in FIG. In addition, the estimated inertia value of the starter motor 9 becomes larger than a predetermined reference value. As a result, the operation of the starter motor 9 becomes normal.
[0119]
  Further, as described at the beginning, in each of the embodiments described so far, an endless member other than the belt may be provided. For example, a chain may be provided instead of the belt. In this case, it is preferable that the sprocket is attached to the crankshaft instead of the pulley, and the chain is wound around the sprocket. The belt abnormality is slip and disconnection (cutting), while the chain abnormality is mainly disconnection, and this disconnection abnormality is detected according to the above-described embodiment.
[0120]
【The invention's effect】
  As described above, according to the present invention, the abnormality of the endless member of the engine starter can be detected, and a fail-safe function can be added by taking measures against the abnormality of the endless member based on the detection result. Thus, the reliability of the vehicle system can be improved.
[Brief description of the drawings]
FIG. 1 is a diagram showing a hybrid system provided with an engine starter according to an embodiment of the present invention.
FIG. 2 is a diagram showing the belt layout of FIG. 1;
FIG. 3 is a block diagram showing the hybrid system of FIG. 1 centering on a configuration relating to belt abnormality detection.
4 is a flowchart showing belt abnormality detection processing of the system of FIG. 3;
FIG. 5 is a diagram illustrating setting of a threshold rotation speed difference and determination timing for belt abnormality determination used in the system of FIG. 3;
[Fig. 6]Reference exampleThis is a block showing the system.
7 is a flowchart showing belt abnormality detection processing of the system of FIG.
[Fig. 8]Embodiment 2FIG. 2 is a diagram showing a configuration of a cooling system of the hybrid system of FIG. 1.
FIG. 9Embodiment 2It is a flowchart which shows the save travel process at the time of belt abnormality by the system of.
FIG. 10Embodiment 3It is a functional block diagram of the engine starting device concerning.
11 is a flowchart of a process of controlling the torque command value of the starter motor 9 in accordance with the inertia of the starter motor 9 in the engine starting device shown in FIG.
FIG. 12 is a diagram showing a time change of the estimated inertia value of the starter motor 9;
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 Engine, 3 Main motor generator, 9 Starter motor, 11 Auxiliary machine, 11a Water pump, 13 Belt, 15 Crank pulley, 19, 19a, 19b Pulley, 30, 40 ECU, 32 Engine rotation sensor, 34 Motor rotation sensor, 36 , 48 Belt abnormality detection unit, 38, 50 abnormality processing unit, 42 water temperature sensor, 44 throttle sensor, 46 radiator electric fan, 72 heater core, 76 electric water pump, 80 inertia estimation unit, 82 torque command value control unit.

Claims (5)

In an engine starter that starts and drives an engine via an endless member such as a belt or a chain by a motor, when an abnormality of the endless member is detected, another motor connected to the engine is failed-safe. An engine starter for starting the engine using a starter motor for the engine. An engine, a motor for driving and starting the engine, a mechanical water pump for cooling the engine, a power transmission belt or chain wound around the engine, the motor and the mechanical water pump, and the like In the engine system including the endless member, an abnormality detecting means for detecting that an abnormality has occurred in the endless member, and when the abnormality has occurred in the endless member, provided separately from the mechanical water pump. And an abnormality handling means for operating the electric water pump as a fail-sale pump. 3. The engine system according to claim 2, wherein when the abnormality handling processing unit detects an abnormality of the endless member, the other motor connected to the engine is used as a fail-safe starting motor. An engine system characterized by starting an engine. In an engine starter for starting an engine by driving the engine through an endless member such as a belt or a chain by a motor, inertia estimating means for estimating inertia from the rotation speed of the motor and the motor acceleration, and the inertia is a predetermined value An engine starter comprising: an abnormality determination unit that determines that an abnormality has occurred in the endless member when: In an engine starter that starts an engine by driving the engine through an endless member such as a belt or a chain by a motor, inertia estimation means for estimating an inertia from the rotational speed of the motor and the motor acceleration, and the inertia is a predetermined Torque command value control means for appropriately controlling a torque command value to the motor so as to be larger than a reference value, and an abnormality occurs in the endless member when the torque command value falls below a predetermined threshold torque command value And an abnormality determination means for determining that the engine has started.

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