JP2009156282A - Vehicular controller - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To perform suitable transmission control depending on a temperature of an electromagnetic clutch while preventing an operation failure of the electromagnetic clutch caused by heat generation in a vehicular controller. <P>SOLUTION: The vehicular controller which performs a change between a continuous variable transmission mode and a fixed stage transmission mode by engaging and releasing the electromagnetic clutch is characterized in that, when the temperature of the electromagnetic clutch detected by a temperature detecting means is higher than a first temperature, the electromagnetic clutch is prohibited in a change of the transmission mode from release to engagement, when the temperature ranges between a second temperature and a third temperature, the electromagnetic clutch is permitted in a change of the transmission mode from engagement to release, until a regular time passes, the electromagnetic clutch is prohibited in the change of the transmission mode from release to engagement, and when the temperature is than a third temperature, the electromagnetic clutch is permitted in the change of the transmission mode from engagement to release. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a control device for a vehicle including a speed change mechanism capable of switching between a continuously variable speed mode and a fixed speed mode.

  Hybrid vehicles that include a power source such as an electric motor or a motor generator in addition to an internal combustion engine are known. In a hybrid vehicle, an internal combustion engine is operated in a highly efficient state as much as possible, while an excess or deficiency of driving force or engine braking force is compensated by an electric motor or a motor generator.

  In the hybrid vehicle as described above, Patent Document 1 describes an example of a speed change mechanism configured to be able to operate by switching between a continuously variable transmission mode and a fixed speed transmission mode. Specifically, a power distribution mechanism having four rotating elements is configured by combining two planetary gear mechanisms, and the four rotating elements are connected to the engine, the first motor generator, the output shaft, and the brake, respectively. In a state where the brake is released, the engine speed is continuously changed by continuously changing the rotation speed of the first motor generator, and the operation in the continuously variable transmission mode is executed. On the other hand, in a state where the brake is fixed, the gear ratio is fixed by preventing the rotation of one of the rotating elements, and the operation in the fixed speed mode is executed. Thus, in Patent Document 1, the power transmission efficiency is improved by properly using the continuously variable transmission mode and the fixed speed transmission mode.

  Patent Document 2 describes a vehicle control device that can prevent the burn of the clutch by suppressing the output of the motor generator when the temperature of the clutch is within a predetermined temperature range.

JP 2004-345527 A Japanese Patent Laid-Open No. 9-74609

  In the hybrid vehicle described in Patent Document 1 described above, when one of the above rotating elements is fixed with a brake in order to shift from the continuously variable transmission mode to the fixed gear transmission mode, the brake generates heat and shifts accordingly. There is a risk of adversely affecting the operation of the mechanism. In order to prevent this, it is necessary to take measures against heat generation for the brake. However, in the above-mentioned Patent Document 1, no examination has been made on heat generation countermeasures for brakes, and a problem remains in this respect.

  Further, in the vehicle control device described in Patent Document 2 described above, the countermeasure for heat generation of the clutch has been studied, but no study on appropriate shift control according to the temperature of the clutch has been made.

  The present invention has been made in view of the above points, and in a vehicle control device including a speed change mechanism that can be operated by switching between a continuously variable speed change mode and a fixed speed change mode, an electromagnetic wave caused by heat generation is provided. An object of the present invention is to perform appropriate shift control in accordance with the temperature of the electromagnetic clutch while preventing malfunction of the clutch.

  In one aspect of the present invention, there is provided a vehicle control device including an engagement mechanism that is engaged by an electromagnetic actuator, and a drive mechanism that changes a transmission mode depending on whether or not the engagement mechanism is engaged. Temperature detecting means for detecting the temperature of the engagement mechanism, and control means for controlling the shift mode in accordance with the detected temperature, wherein the control means is configured when the engagement mechanism is in a released state. When the detected temperature is higher than the first temperature, the change of the shift mode is prohibited, and when the engagement mechanism is in the engaged state, the detected temperature is in the range from the second temperature to the third temperature. In this case, the change of the shift mode for changing the engagement mechanism from the engagement state to the release state is permitted, and the engagement mechanism is moved from the release state to the engagement state until a specified time after the change of the shift mode has elapsed. Combined state The change of the shift mode to be changed is prohibited, and when the detected temperature is higher than the third temperature when the engagement mechanism is in the engagement state, the engagement mechanism is changed from the engagement state to the release state. Permits changing the shifting mode to be changed.

  The vehicle control apparatus has an engagement mechanism (corresponding to the electromagnetic clutch in the present embodiment) that is engaged by an electromagnetic actuator, and the presence or absence (engagement / release) of the engagement mechanism. A drive mechanism for changing the transmission mode is provided. The vehicle control device includes temperature detection means for detecting the temperature of the engagement mechanism, and control means (corresponding to the third MGECU and the like in the present embodiment) for controlling engagement and release of the engagement mechanism. Examples of the temperature detecting means include various known means such as a temperature sensor and a means for calculating the resistance value based on the electric power supplied to the electromagnetic actuator and estimating the temperature of the engagement mechanism based on the resistance value. Can be mentioned.

  In particular, in this vehicle control device, when the engagement mechanism is in the disengaged state, when the detected temperature of the engagement mechanism detected by the temperature detection means is higher than the first temperature, the control means Prohibit mode change. In a preferred example, when the detected temperature is higher than the first temperature, the control means changes the speed change mode for changing the engagement mechanism from the released state to the engaged state, that is, continuously variable speed change. Transition from mode to fixed speed mode is prohibited.

  Here, the first temperature corresponds to the first threshold in the present embodiment, and the first threshold is a temperature at which the engagement mechanism cannot function (operate) normally, for example. This prevents the engagement mechanism from functioning normally due to the high temperature of the engagement mechanism.

  Further, when the engagement mechanism is in the engaged state and the detected temperature is in the range from the second temperature to the third temperature, the control means releases the engagement mechanism from the engaged state. The change of the shift mode to be changed to (that is, the transition from the fixed speed change mode to the continuously variable speed change mode) is permitted, but the specified time after the change (at the first standby time or the first specified time in the present embodiment) Change of the speed change mode in which the engagement mechanism is changed from the disengaged state to the engaged state (that is, transition from the continuously variable speed change mode to the fixed speed change mode) is prohibited.

  Here, the third temperature is, for example, a temperature at which the engagement mechanism cannot function (operate) normally. On the other hand, the second temperature is lower than the third temperature, but is a temperature at which the engagement mechanism has heat than usual. Further, the waiting time is a period for prohibiting the engagement mechanism from being turned off (released state) to being turned on (engaged state) and cooling the engagement mechanism.

  Therefore, after releasing the engagement of the engagement mechanism once, the engagement mechanism temperature is high in a state where the specified time has not elapsed, so the transition from the continuously variable transmission mode to the fixed speed transmission mode is not performed. Wait for the specified time. Thereby, the temperature of the engagement mechanism can be lowered, and the engagement mechanism can be prevented from malfunctioning due to the heat generation.

  Further, when the engagement mechanism is in the engagement state, if the detected temperature is higher than the third temperature, the control unit changes the shift mode for changing the engagement mechanism from the engagement state to the release state. (That is, transition from the fixed speed mode to the continuously variable speed mode) is permitted. In a preferred example, when the detected temperature is higher than the third temperature, the control means permits the change of the shift mode for changing the engagement mechanism from the engaged state to the released state. The shift mode in which the engagement mechanism is changed from the released state to the engaged state until another specified time (corresponding to the second standby time or the second specified time in the present embodiment) elapses after the change. Changes are prohibited.

  Therefore, in this case, since the temperature of the engagement mechanism is high in a state where the other specified time has not elapsed, the transition from the continuously variable transmission mode to the fixed speed transmission mode is not performed for a while for the other specified time. stand by. Here, when the temperature of the engagement mechanism exceeds the third temperature, the heat dissipation is required more than when the temperature is between the second temperature and the third temperature. It is preferable to set the time longer than the specified time. This prevents the engagement mechanism from functioning normally due to the high temperature of the engagement mechanism.

  According to the vehicle control apparatus having the above-described configuration, it is possible to prevent malfunction of the engagement mechanism caused by the high temperature of the engagement mechanism, and to perform appropriate shift control according to the detected temperature of the engagement mechanism. It can be performed.

  Preferred embodiments of the present invention will be described below with reference to the drawings.

[Configuration of hybrid vehicle drive mechanism]
FIG. 1 shows a schematic configuration of a drive mechanism of a hybrid vehicle to which the present invention is applied. The example of FIG. 1 is a hybrid vehicle called a mechanical distribution type two-motor type, and includes an engine 1, a first motor generator MG 1, a second motor generator MG 2, and a power distribution mechanism 20. An engine 1 corresponding to a power source and a first motor generator MG1 corresponding to a rotation speed control mechanism are connected to a power distribution mechanism 20. The output shaft 3 of the power distribution mechanism 20 is connected to a second motor generator MG2 that is a sub power source for assisting drive torque or braking force. Second motor generator MG2 and output shaft 3 are connected via MG2 transmission 6. Further, the output shaft 3 is connected to the left and right drive wheels 9 via a final reduction gear 8. The first motor generator MG1 and the second motor generator MG2 are electrically connected via a battery, an inverter, or an appropriate controller (not shown) or directly, and the first motor generator MG1 The second motor generator MG2 is driven by the generated electric power.

  The engine 1 is a heat engine that generates power by burning fuel, and examples thereof include a gasoline engine and a diesel engine. The first motor generator MG1 generates power mainly by receiving torque from the engine 1 and rotating, and reaction force torque accompanying power generation acts. By controlling the rotational speed of first motor generator MG1, the rotational speed of engine 1 changes continuously. Such a speed change mode is called a continuously variable speed change mode. The continuously variable transmission mode is realized by a differential action of a power distribution mechanism 20 described later.

  The second motor generator MG2 is a device that assists the driving torque or the braking force. When assisting the drive torque, the second motor generator MG2 receives power supply and functions as an electric motor. On the other hand, when assisting the braking force, the second motor generator MG2 functions as a generator that is rotated by the torque transmitted from the drive wheels 9 to generate electric power.

  FIG. 2 shows a configuration of first and second motor generators MG1 and MG2 and power distribution mechanism 20 shown in FIG.

  The power distribution mechanism 20 is a mechanism that distributes the output torque of the engine 1 to the first motor generator MG1 and the output shaft 3, and is configured to generate a differential action. Specifically, the engine 1 is connected to the first rotating element among the four rotating elements that are provided with a plurality of sets of differential mechanisms and have a differential action, and the first motor generator MG1 is connected to the second rotating element. Are connected, the output shaft 3 is connected to the third rotating element, and the electromagnetic clutch 80 is connected to the fourth rotating element. In a state where the electromagnetic clutch 80 is released, the rotation speed of the engine 1 is continuously changed by continuously changing the rotation speed of the first motor generator MG1, and the continuously variable transmission mode is realized. On the other hand, when the electromagnetic clutch 80 is engaged and the fourth rotation element is fixed, the gear ratio determined by the power distribution mechanism 20 is fixed to the overdrive state (that is, the engine speed is smaller than the output speed). Thus, the fixed speed mode is realized.

  In the present embodiment, as shown in FIG. 2, the power distribution mechanism 20 is configured by combining two planetary gear mechanisms. The first planetary gear mechanism includes a ring gear 21, a carrier 22, and a sun gear 23, and the second planetary gear mechanism includes a ring gear 25, a carrier 26, and a sun gear 27.

  The output shaft 2 of the engine 1 is connected to the carrier 22 of the first planetary gear mechanism, and the carrier 22 is connected to the ring gear 25 of the second planetary gear mechanism. These constitute the first rotating element. The rotor 11 of the first motor generator MG1 is connected to the sun gear 23 of the first planetary gear mechanism, and these constitute a second rotating element.

  The ring gear 21 of the first planetary gear mechanism and the carrier 26 of the second planetary gear mechanism are connected to each other and to the output shaft 3. These constitute the third rotating element. The sun gear 27 of the second planetary gear mechanism corresponds to the fourth rotating element and is connected to the electromagnetic clutch 80.

  FIG. 3A shows a configuration example of the electromagnetic clutch 80. FIG. 3A shows a cross-sectional view of the main part of the electromagnetic clutch 80. In this example, the electromagnetic clutch 80 corresponds to the engagement mechanism of the present invention, and includes an electromagnetic actuator 60, a clutch 70 including a pair of dog teeth 71 and 72, a temperature sensor (temperature detecting means shown in FIG. 4) 90, and , And is configured.

  The electromagnetic actuator 60 is driven and controlled based on a signal output from an electromagnetic clutch drive circuit 51 described later, and moves one dog tooth 71 to engage or release one dog tooth 71 with the other dog tooth 72. Play a role. The electromagnetic actuator 60 includes a shaft 61, a sliding bearing 62, a pair of plungers 63 and 64 made of a metal material, a yoke 65, a coil 66, a return spring 67, and a case 68.

  At least a part of the outer peripheral surface of the shaft 61 is provided with a sliding bearing 62 for moving one plunger 63 in a direction in which the other plunger 64 is engaged with the other plunger 64 and in the opposite direction (arrow Y1 direction). One plunger 63 is attached to the sliding bearing 62. The other plunger 64 has a shape that engages with one plunger 63, and is attached to the inside of the case 68 so as to face the one plunger 63. The yoke 65 is a magnetic body, for example, and is disposed outside the pair of plungers 63 and 64. A part of the yoke 65 is in contact with a part of the pair of plungers 63. The coil 66 is disposed between the yoke 65 and the pair of plungers 63 and 64, and electric power is supplied to the coil 66 through the electromagnetic clutch drive circuit 51. The return spring 67 is a push spring that is attached to a shaft 61 positioned between a part of one plunger 63 and the inside of the case 68 and acts in a direction in which one plunger 63 is pulled away from the other plunger 64. The case 68 is fixed to a vehicle body or the like, and houses a shaft 61, a sliding bearing 62, a pair of plungers 63 and 64, a yoke 65, a coil 66, and a return spring 67, respectively.

  One dog tooth 71 is a fixed member configured to be non-rotatable, and can move in the same direction as the one plunger 63 (in the direction of arrow Y2) and by the same distance as the plunger 63 moves. It is supported on the wall surface of the electromagnetic actuator 60 in a state. A plurality of internal teeth 71 a are provided on the inner peripheral surface on one end side of one dog tooth 71.

  The other dog tooth 72 is a rotating member configured to be rotatable, and is connected to the sun gear 27 of the second planetary gear mechanism. For this reason, the other dog tooth 72 rotates in accordance with the rotation of the sun gear 27 that is the fourth rotating element. A plurality of external teeth for engaging with the plurality of internal teeth 71 a of one dog tooth 71 are provided on the outer peripheral portion of the other dog tooth 72.

  Although not shown in FIG. 3A, the temperature sensor (temperature detection means) 90 is provided, for example, at a position in contact with the coil 66, and the coil 66 that generates heat due to the supply of electric power based on a command signal from the third MGECU 34. Detect temperature. The temperature data of the coil 66 detected by the temperature detection means 90 is output to the third MGECU 34. As a result, the third MGECU 34 detects the temperature of the coil 66 and further the temperature of the electromagnetic clutch 80. In the present invention, it is not essential to provide the temperature detecting means 90 at a position in contact with the coil 66. If the temperature of the electromagnetic clutch 80 can be detected, the temperature detecting means 90 is provided at any position of the electromagnetic clutch 80. May be. In the present invention, the temperature detecting means 90 is not particularly required to be a temperature sensor. For example, the resistance value is calculated from the power supplied to the coil 66 of the electromagnetic actuator 60, and the temperature is estimated based on the resistance value. It may be a means capable of.

  In the electromagnetic clutch 80 having the above-described configuration, a magnetic field is formed around the coil 66 by supplying predetermined power to the coil 66 through the electromagnetic clutch drive circuit 51 under a command signal from a third MGECU 34 to be described later. Magnetic flux is generated in 65. As a result, one plunger 63 in contact with a part of the yoke 65 is magnetized. For this reason, one plunger 63 is attracted by the other plunger 64 that is disposed to face the other at a predetermined interval, and resists against the elastic force of the return spring 67 toward the other plunger 64 on the slide bearing 62. Move and engage the other plunger 64. Along with this, one dog tooth 71 is engaged with the other dog tooth 72, and the electromagnetic clutch 80 is turned on (engaged state). In this case, since the shaft on the one dog tooth 71 side is fixed, the sun gear 27 as the fourth rotating element is fixed, that is, the rotation of the sun gear 27 is prevented.

  On the other hand, when the supply of electric power to the coil 66 is stopped through the electromagnetic clutch drive circuit 51 under the command signal from the third MGECU 34, the one plunger 63 is not magnetized, so that the one plunger 63 is moved by the elastic force of the return spring 67. It moves on the sliding bearing 62 in the direction away from the other plunger 64, and the engagement between one plunger 63 and the other plunger 64 is released. Accordingly, the engagement between one dog tooth 71 and the other dog tooth 72 is released, and the electromagnetic clutch 80 is turned off (released state).

  Returning to FIG. 2, the first motor generator MG <b> 1 is provided with a resolver 12 that detects the rotation of the rotor 11. The rotor 41 of the second motor generator MG2 is connected to the output shaft via the MG2 transmission 6 and a resolver 42 that detects the rotation of the rotor 41 is provided. As shown in FIG. 2, the electromagnetic clutch 80 is provided with a resolver 32 that detects rotation on the other dog tooth 72 side.

  As described above, when the electromagnetic clutch 80 is released (off), the continuously variable transmission mode is set. Specifically, the output torque of the engine 1 acts on the carrier 22 that is the first rotating element, and the reaction force torque by the first motor generator 23 acts on the sun gear 23 that is the second rotating element. A torque that rotates in the same direction as the engine 1 acts on the output shaft 3 that is the third rotation element and the sun gear 27 that is the fourth rotation element. In this case, the rotational speed of engine 1 changes according to the rotational speed change of first motor generator MG1, and the operation in the continuously variable transmission mode is performed.

  On the other hand, when the electromagnetic clutch 80 is in the engaged (on) state, the fixed speed mode is set. Specifically, when the rotation of the sun gear 27, which is the fourth rotation element, is stopped, a reaction force torque is applied to the rotation of the engine 1 by the electromagnetic clutch 80. Therefore, the first motor generator MG1 is a so-called idle rotation. It becomes a state. As a result, the speed ratio determined by the configuration of the power distribution mechanism 20 is fixed, and the operation in the fixed speed mode is performed.

[Configuration of control system for hybrid vehicle]
FIG. 3B shows the configuration of a control system that controls the motor generator and the electromagnetic clutch 80. In the control system of the present embodiment, as shown in the figure, a first MGECU 14 and a second MGECU 44 are provided so as to drive and control the first motor generator MG1 and the second motor generator MG2 independently.

  The first MGECU 14 supplies driving power to the first motor generator through the inverter 13 to the MG1. The rotation of first motor generator MG1 is detected by resolver 12 and sent to first MGECU 14. First MGECU 14 controls the rotation of first motor generator MG1 based on the rotation detection signal from resolver 12.

  Similarly, the second MGECU 44 supplies drive power to the second motor generator through the inverter 43 to the MG2. The rotation of the second motor generator MG2 is detected by the resolver 42 and sent to the second MGECU 44. Second MGECU 44 controls the rotation of second motor generator MG2 based on the rotation detection signal from resolver 42.

  As described with reference to FIG. 2, the resolver 32 provided in the electromagnetic clutch 80 detects the rotation of the shaft on the dog tooth 72 side and supplies a clutch rotation detection signal to the third MGECU 34. The third MGECU 34 supplies the clutch rotation detection signal from the resolver 32 to the second MGECU 44. Further, the third MGECU 34 controls the electromagnetic clutch drive circuit 51 based on the control signal given from the second MGECU 44 to control on / off of the electromagnetic clutch 80.

  Further, in the present embodiment, an HVECU 9 that controls the first MGECU 14 and the second MGECU 44 provided for each motor generator is provided. The HVECU 9 is connected to the second MGECU 44 and supplies control instructions and control command values to the first MGECU 14 and the third MGECU 34 through the second MGECU 44.

[Shift control according to electromagnetic clutch temperature]
Next, the shift control according to the temperature of the electromagnetic clutch 80 according to the present embodiment will be described.

  In the hybrid vehicle as in the present embodiment, the operation is performed by switching between the continuously variable transmission mode and the fixed gear transmission mode. However, if the operation in the fixed gear transmission mode is frequently performed, the electromagnetic clutch 80 may be seized. There is a risk of adversely affecting the change of the transmission mode.

  Specifically, in such a hybrid vehicle, the electromagnetic clutch 80 is turned on by supplying electric power to the coil 66 of the electromagnetic actuator 60, and the driving is performed in the fixed speed mode. In this case, since the coil 66 generates heat when the coil 66 is energized, the heat is transmitted to the entire electromagnetic actuator 60 and the clutch 70. Therefore, if the operation in the fixed speed mode is frequently performed, the temperature of the electromagnetic clutch 80 becomes high, and depending on the temperature, the coil 66 may be seized and the change of the speed mode may be hindered. .

  Therefore, in the present embodiment, the temperature of the electromagnetic clutch 80 (for example, the electromagnetic actuator 60) is detected (or estimated) by the temperature detecting means 90, and an appropriate shift mode is changed according to the detected (or estimated) temperature. Thus, the above-described problems are solved.

  Specifically, in the present embodiment, first, the temperature of the electromagnetic clutch 80 is detected (or estimated) by the temperature detection means 90 in a state where the electromagnetic clutch 80 is released (operation state in the continuously variable transmission mode), When the detected temperature exceeds the first threshold value (first temperature comparison value), it is prohibited to change the electromagnetic clutch 80 from the off state (released state) to the on state (engaged state). . Here, the first threshold value is a value at which the electromagnetic clutch 80 cannot function (operate) normally, for example. This can prevent the electromagnetic clutch 80 from functioning normally due to the high temperature of the electromagnetic clutch 80.

  Further, in a state where the electromagnetic clutch 80 is engaged (an operation state in the fixed speed mode), the detected temperature of the electromagnetic clutch 80 is set to the second threshold value (second temperature comparison value) and the third threshold value (first value). 3), the operation in the fixed speed mode is continued for the time being. However, after the change from the fixed speed mode to the continuously variable speed mode is performed in consideration of the fuel efficiency and the like, the electromagnetic clutch 80 is kept until the first specified time (first waiting time) elapses. Changing from the released state to the engaged state is prohibited. Here, the third threshold value is set to a value at which the electromagnetic clutch 80 cannot function normally, for example. Further, the third threshold value is larger than the second threshold value. Furthermore, the standby time is a period for prohibiting the electromagnetic clutch 80 from being released to being engaged and cooling the electromagnetic clutch 80.

  Therefore, in this case, in a state where the first standby time has not elapsed, the temperature of the electromagnetic clutch 80 is high, so that the transition from the continuously variable transmission mode to the fixed gear transmission mode is not performed for a first standby time. stand by. Thereby, the temperature of the electromagnetic clutch 80 can be lowered, and the electromagnetic clutch 80 can be prevented from functioning normally due to the heat generation.

  On the other hand, when the detected temperature of the electromagnetic clutch 80 exceeds the third threshold value with the electromagnetic clutch 80 engaged, the electromagnetic clutch 80 is immediately changed from the engaged state to the released state, and thereafter It is prohibited to change the electromagnetic clutch 80 from the disengaged state to the engaged state until the second specified time (second waiting time) has elapsed. Therefore, in this case, when the second standby time has not elapsed, the temperature of the electromagnetic clutch 80 is still high, so that the transition from the continuously variable transmission mode to the fixed gear transmission mode is not performed, and only the second standby time is performed. Wait for a while. Here, when the temperature of the electromagnetic clutch 80 exceeds the third threshold value, the heat release is required more than when the temperature is between the second threshold value and the third threshold value. It is preferable to make the time larger than the first waiting time. This can prevent the electromagnetic clutch from functioning normally due to the high temperature of the electromagnetic clutch 80.

  As described above, according to the present embodiment, it is possible to prevent malfunction of the electromagnetic clutch caused by the high temperature of the electromagnetic clutch, and to perform appropriate shift control according to the detected temperature of the electromagnetic clutch 80. Can do.

[Shift control processing according to the temperature of the electromagnetic clutch]
Next, with reference to FIG. 4, the shift control process according to the temperature of the electromagnetic clutch 80 according to the present embodiment will be described. FIG. 4 shows a flowchart according to an example of a shift control process according to the temperature of the electromagnetic clutch 80. This process is mainly repeatedly executed by the third MGECU 34 (or HVECU 9) shown in FIG.

  In this example of the shift control process, first, the third MGECU 34 controls the driving of the electromagnetic clutch 80 through the electromagnetic clutch drive circuit 51 and performs the driving (running) in the continuously variable transmission mode in which the electromagnetic clutch 80 is turned off. (Step S1). Next, the third MGECU 34 determines whether or not the shift waiting time flag N (N: natural number) is in an OFF state (step S2).

  Here, the shift waiting time flag N is set to one of two states, ON (on) and OFF (off). The first shift waiting time flag N in this process is in an OFF state, and the shift waiting time flag N is turned ON by executing step S9 or step S13 described later, and each step after step S9 or step S13 is executed. After stepping, the process returns to step S3, and when the determination in step S3 is YES, the shift waiting time flag N is turned off. The meaning of the standby time in the shift standby time flag N will be described later.

  If the shift waiting time flag is not OFF (step S2; NO), the process proceeds to step S3. Here, since the first shift waiting time flag N in this process is in the OFF state, the description of step S3 will be described later.

  On the other hand, when the shift waiting time is OFF (step S2; YES), the third MGECU 34 can operate the electromagnetic clutch 80 normally without causing a short circuit or disconnection in the coil 66 of the electromagnetic actuator 60. It is determined whether or not it is in a state, and whether or not the detected temperature (or estimated temperature) of the electromagnetic clutch 80 detected (or estimated) by the temperature detecting means 90 is smaller than a first threshold ( Step S4). When the electromagnetic clutch 80 is in a state in which it cannot be normally operated, and when the detected temperature of the electromagnetic clutch 80 is not lower than the first threshold (step S4; NO), the third MGECU 34 is continuously variable. The determination to shift from the shift mode to the fixed speed mode is not performed. In this case, the process returns to step S1, and the third MGECU 34 continues to operate in the continuously variable transmission mode.

  On the other hand, when the electromagnetic clutch 80 can be normally operated and the detected temperature of the electromagnetic clutch 80 is lower than the first threshold (step S4; YES), the electromagnetic clutch 80 is engaged. There is no problem even when shifting from the continuously variable transmission mode to the fixed transmission mode. Therefore, in this case, the third MGECU 34 determines whether or not the transition from the continuously variable transmission mode to the fixed gear transmission mode may be made in consideration of other conditions (step S5). When the transition to the fixed speed mode is not permitted (or prohibited) (step S5; NO), the process returns to step S1, and the third MGECU 34 continues the operation in the continuously variable speed mode. On the other hand, when the transition to the fixed speed mode is permitted (step S5; YES), the third MGECU 34 controls the driving of the electromagnetic clutch 80 through the electromagnetic clutch drive circuit 51 to turn on the electromagnetic clutch 80 (engagement). Transition to the fixed speed mode (step S6). Since the temperature of the electromagnetic clutch 80 rises due to the shift to the fixed speed mode, the third MGECU 34 detects (or estimates) the temperature of the electromagnetic clutch 80 again through the temperature detection means 90 (step S7).

  That is, when driving in the fixed speed mode, the electromagnetic clutch 80 is in the on state (engaged state). In this case, the coil 66 of the electromagnetic actuator 60 maintains the engagement between the one dog tooth 71 and the other dog tooth 72 (in other words, the one plunger 63 in the engaged state with the other plunger 64 is restored. In order not to be released from the other plunger 64 by the elastic force of the spring 67), a predetermined amount of electric power is supplied. Therefore, in this state, the temperature of the electromagnetic clutch 80 rises due to heat generated from the coil 66. For this reason, the third MGECU 34 detects (or estimates) the temperature of the electromagnetic clutch 80 again.

  Next, the third MGECU 34 determines whether or not the detected temperature of the electromagnetic clutch 80 is greater than or equal to a third threshold value (step S8).

  If the detected temperature of the electromagnetic clutch 80 is greater than or equal to the third threshold (step S8; YES), the third MGECU 34 turns on the shift waiting time flag 2 (step S9). Subsequently, the third MGECU 34 immediately releases the engagement of the electromagnetic clutch 80 through the electromagnetic clutch drive circuit 51 (step S10), and shifts from the fixed speed mode to the continuously variable speed mode (step S11).

  Now, returning to step S8, when the detected temperature of the electromagnetic clutch 80 is lower than the third threshold value (step S8; NO), the third MGECU 34 determines whether the detected temperature of the electromagnetic clutch 80 is higher than the second threshold value. Is determined (step S12).

  When the detected temperature of the electromagnetic clutch 80 is not higher than the second threshold (step S12; NO), the process proceeds to step S14, and the third MGECU 34 continues the operation in the fixed speed mode. On the other hand, when the detected temperature of the electromagnetic clutch 80 is higher than the second threshold, that is, when the second threshold <the detected temperature of the electromagnetic clutch 80 <the third threshold is satisfied (step S12; YES), the third MGECU 34 Then, the shift standby time flag 1 is set to the ON state (step S13), and the operation in the fixed speed mode is continued (step S14). Thereafter, the third MGECU 34 performs a determination for shifting from the fixed-stage transmission mode to the continuously-variable transmission mode in consideration of the necessity of shifting from the fixed-stage transmission mode to the continuously-variable transmission mode in view of fuel efficiency and the like. (Step S15).

  When the transition to the continuously variable transmission mode is not permitted (or prohibited) (step S15; NO), the process returns to step S14, and the third MGECU 34 continues the operation in the fixed speed transmission mode. On the other hand, when the transition to the continuously variable transmission mode is permitted (step S15; YES), the third MGECU 34 releases the engagement of the electromagnetic clutch 80 through the electromagnetic clutch drive circuit 51 (step S10), and further, the fixed-stage transmission. The mode is shifted to the continuously variable transmission mode (step S11).

  In the next shift control process, the third MGECU 34 continues the operation in the continuously variable transmission mode (step S1) and further determines whether or not the shift standby time flag 2 is in the OFF state (step S2). If the shift waiting time flag 2 is in the ON state by the execution of step S9 (step S2; NO), the third MGECU 34 has elapsed time from the previous shift mode (that is, the fixed gear shift mode in step S6). Is greater than the waiting time (here, equivalent to the second waiting time or the second specified time) (step S3).

  Here, the standby time is a period for prohibiting the electromagnetic clutch 80 from being turned off (released state) to being turned on (engaged state) and cooling the electromagnetic clutch 80. Therefore, when the elapsed time from the previous shift mode is not longer than the second standby time (step S3; NO), the temperature of the electromagnetic clutch 80 is high, and the process returns to step S1. In other words, after the determination in step S4, the determination (step S5) for shifting from the continuously variable transmission mode to the fixed speed transmission mode is not performed for the second standby time, and the process waits for a while. Thereby, the temperature of the electromagnetic clutch 80 can be reduced, and it can prevent that the electromagnetic clutch 80 resulting from the heat_generation | fever functions normally.

On the other hand, when the elapsed time from the previous shift mode is longer than the second standby time (step S3; YES), the temperature of the electromagnetic clutch 80 is sufficiently lowered, and the electromagnetic clutch 80 is caused by the generated heat. Since there is no possibility that will not function normally, the process proceeds to step S4.

  In the next shift control process, when the shift waiting time flag 1 is in the ON state by executing step S13 (step S2; NO), the third MGECU 34 determines that the previous shift mode (that is, the fixed stage in step S6). It is determined whether or not the elapsed time from the shift mode is longer than the standby time (corresponding to the first standby time or the first specified time here) (step S3).

  Here, when the temperature of the electromagnetic clutch 80 exceeds the third threshold value, the heat release is required more than when the temperature is between the second threshold value and the third threshold value. It is preferable to make the time larger than the first waiting time.

  If the elapsed time from the previous shift mode is not greater than the first standby time (step S3; NO), the heat release of the electromagnetic clutch 80 is not yet sufficient, so the process returns to step S1 and the determination of step S4 is performed. Waiting for a while without performing the determination (step S5) for shifting from the continuously variable transmission mode to the fixed gear transmission mode for the first standby time. Thereby, the temperature of the electromagnetic clutch 80 can be lowered, and the electromagnetic clutch 80 can be prevented from functioning normally due to the heat generation.

  On the other hand, when the elapsed time from the previous shift mode is longer than the first standby time (step S3; YES), the temperature of the electromagnetic clutch 80 is sufficiently lowered, and the electromagnetic clutch 80 is caused by the generated heat. Does not stop functioning normally, so the process proceeds to step S4.

The schematic structure of the drive mechanism of the hybrid vehicle which concerns on this embodiment is shown. The structure of a motor generator and a power distribution mechanism is shown. The structure of an electromagnetic clutch and the structure of the control system of a hybrid vehicle are shown. The flowchart which concerns on the speed-change control process according to the temperature of the electromagnetic clutch which concerns on this embodiment is shown.

Explanation of symbols

1 Engine 9 HVECU
14 1st MGECU
12, 32, 42 Resolver 20 Power distribution mechanism 34 3rd MGECU
44 2nd MGECU
51 Electromagnetic clutch drive circuit 60 Electromagnetic actuator 63, 64 Plunger 66 Coil 67 Return spring 70 Clutch 71, 72 Dog teeth 80 Electromagnetic clutch 90 Temperature detection means

Claims (3)

A vehicle control device including an engagement mechanism that is engaged by an electromagnetic actuator, and a drive mechanism that changes a speed change mode depending on whether or not the engagement mechanism is engaged.
Temperature detecting means for detecting the temperature of the engagement mechanism;
Control means for controlling the speed change mode according to the detected temperature,
The control means prohibits the change of the shift mode when the detected temperature is higher than the first temperature when the engagement mechanism is in the released state, and when the engagement mechanism is in the engaged state. When the detected temperature is in the range from the second temperature to the third temperature, the change of the shift mode for changing the engagement mechanism from the engaged state to the released state is permitted and the post-change regulation of the shift mode is permitted. Until the time elapses, the change of the shift mode for changing the engagement mechanism from the released state to the engaged state is prohibited, and the detected temperature is the third temperature when the engagement mechanism is in the engaged state. If higher, the vehicle control device permits the change of the shift mode for changing the engagement mechanism from the engaged state to the released state.   2. The vehicle according to claim 1, wherein when the detected temperature is higher than the first temperature, the control unit prohibits a change in a shift mode for changing the engagement mechanism from the released state to the engaged state. Control device.   The control means is a shift mode for changing the engagement mechanism from the engagement state to the release state when the engagement mechanism is in the engagement state and the detected temperature is higher than the third temperature. The change in the shift mode for changing the engagement mechanism from the disengaged state to the engaged state is prohibited until another specified time elapses after the change of the shift mode. The vehicle control device described in 1.

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