JP2019138357A - Controller of transmission and method for controlling transmission - Google Patents

Abstract

To reduce regulation of driving force to prevent drivability from being impaired over as long a period as possible until bringing a car to a dealer in a case where abnormality occurs in an oil temperature sensor.SOLUTION: A controller 10 is configured to, after it is determined that abnormality occurs in an oil temperature sensor 58, when based on a heat radiation amount Tr of an automatic transmission 3 after the determination of the abnormality, a heat generation amount Tg of the automatic transmission 3 after the determination of the abnormality, and the latest actual oil temperature Tn among actual oil temperatures determined to be normal, a calculated oil temperature Tc of the calculated automatic transmission 3 exceeds a predetermined value, execute high oil temperature control of protecting the automatic transmission 3.SELECTED DRAWING: Figure 2

Description

  The present invention relates to a transmission control device and a transmission control method.

  Patent Document 1 discloses a method for determining an abnormality of an oil temperature sensor in a transmission.

JP-A-7-301315

  As a countermeasure when the oil temperature sensor is determined to be abnormal, for example, when the oil temperature sensor abnormality occurs, the controller (ATCU) determines that the oil temperature has reached the calculated oil temperature equal to or higher than a predetermined oil temperature, and the high oil temperature control ( It is conceivable to execute (protection control). As the high oil temperature control, for example, it is conceivable to perform driving force regulation such as lowering the rotational speed of the driving source.

  On the other hand, when an abnormality occurs in the oil temperature sensor, a warning is issued in the vehicle to urge the driver to bring the vehicle to the dealer.

  However, as described above, if the driving force is restricted when an abnormality occurs in the oil temperature sensor, the drivability deteriorates immediately when the abnormality occurs in the oil temperature sensor. For this reason, drivability until the vehicle is brought to the dealer is impaired.

  The present invention has been made in view of such a technical problem, and relaxes the driving force regulation until the vehicle is brought to the dealer when an abnormality occurs in the oil temperature sensor, and the drivability is as long as possible. The purpose is not to damage.

  According to an aspect of the present invention, a transmission control device that controls a transmission having an oil temperature sensor that detects an actual oil temperature is a transmission that has been determined to be abnormal after the oil temperature sensor has been determined to be abnormal. If the calculated oil temperature of the transmission, which is calculated based on the amount of heat released, the amount of heat generated by the transmission after the abnormality is determined, and the latest actual oil temperature among the actual oil temperatures determined to be normal, exceeds a predetermined value, the gear shifts. It has a control part which performs high oil temperature control which protects a machine.

  According to another aspect of the present invention, there is provided a transmission control method for controlling a transmission having an oil temperature sensor that detects an actual oil temperature, after the abnormality determination of the oil temperature sensor has been made. When the calculated oil temperature of the transmission, which is calculated based on the heat radiation amount of the machine, the heat generation amount of the transmission after the abnormality determination, and the latest actual oil temperature among the actual oil temperatures determined to be normal is equal to or higher than a predetermined value High oil temperature control for protecting the transmission is performed.

  According to these aspects, the driving force regulation can be relaxed until the vehicle is brought to the dealer when an abnormality occurs in the oil temperature sensor. Therefore, the drivability can be kept as long as possible.

1 is a schematic configuration diagram of a vehicle according to an embodiment of the present invention. It is a flowchart of the high oil temperature control which concerns on embodiment of this invention. It is a flowchart which shows the procedure which calculates the calculation oil temperature Tca. It is a flowchart which shows the procedure which calculates the correction value C. It is the figure which showed the relationship between the actual oil temperature Tn, the calculation oil temperature Tca, and the calculation oil temperature Tcb. It is the figure which showed the correction value Cn.

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

  FIG. 1 is a schematic configuration diagram of a vehicle 100. The vehicle 100 includes an engine 1, an automatic transmission 3, an oil pump 5, drive wheels 6, and a controller 10 as a control device.

  The engine 1 is an internal combustion engine that uses gasoline, light oil, or the like as fuel, and functions as a driving source for traveling. The engine 1 is controlled in rotational speed, torque, and the like based on a command from the controller 10.

The automatic transmission 3 includes a torque converter 2, a fastening element 31, a belt-type continuously variable transmission mechanism (hereinafter also referred to as “CVT”) 30, and a hydraulic control valve unit 40 (hereinafter simply “valve unit 40”). And an oil pan 32 for storing oil (hydraulic oil).

  The torque converter 2 is provided on a power transmission path between the engine 1 and the drive wheels 6. The torque converter 2 transmits power through the fluid. Further, the torque converter 2 can increase the power transmission efficiency of the driving force from the engine 1 by fastening the lock-up clutch 2a.

  Fastening element 31 is arranged on a power transmission path between torque converter 2 and CVT 30. The fastening element 31 is controlled by oil regulated by the valve unit 40 using the discharge pressure of the oil pump 5 as a base pressure based on a command from the controller 10. As the fastening element 31, for example, a normally open wet multi-plate clutch is used. The fastening element 31 may be configured by a forward clutch and a reverse brake (not shown).

  The CVT 30 is disposed on the power transmission path between the fastening element 31 and the drive wheel 6 and changes the speed ratio steplessly according to the vehicle speed, the accelerator opening, and the like. The CVT 30 includes a primary pulley 30a, a secondary pulley 30b, and a belt 30c wound around the pulleys 30a and 30b. The gear ratio is changed steplessly by moving the movable pulley of the primary pulley 30a and the movable pulley of the secondary pulley 30b in the axial direction by the pulley pressure and changing the pulley contact radius of the belt 30c. Note that the pulley pressure acting on the primary pulley 30a and the pulley pressure acting on the secondary pulley 30b are regulated by the valve unit 40 using the discharge pressure from the oil pump 5 as a source pressure.

  The differential 12 is connected to the output shaft of the secondary pulley 30b of the CVT 30 via a final reduction gear mechanism (not shown). The drive wheel 6 is connected to the differential 12 via a drive shaft 13.

  The oil pump 5 is driven by transmitting the rotation of the engine 1 through a belt. The oil pump 5 is constituted by a vane pump, for example. The oil pump 5 sucks up the oil stored in the oil pan 32 and supplies the oil to the valve unit 40. The oil supplied to the valve unit 40 is used for driving the pulleys 30a and 30b, driving the fastening element 31, and lubricating each element of the automatic transmission 3.

  The controller 10 includes a microcomputer having a central processing unit (CPU), a read only memory (ROM), a random access memory (RAM), and an input / output interface (I / O interface). The controller 10 can be composed of a plurality of microcomputers. Specifically, the controller 10 can be configured by an ATCU that controls the automatic transmission 3, an SCU that controls the shift range, an ECU that controls the engine 1, and the like. In addition, the control part in this embodiment makes the function which performs the high oil temperature control mentioned later of the controller 10 into a virtual unit, and does not mean a physical presence.

  The controller 10 includes a first rotation speed sensor 51 that detects the rotation speed Ne of the engine 1, a second rotation speed sensor 52 that detects the output rotation speed Nout of the fastening element 31 (= the rotation speed of the primary pulley 30a), and the accelerator opening. An accelerator opening sensor 53 for detecting the degree, an inhibitor switch 54 for detecting a select range of the CVT 30 (a state of a select lever or a select switch for switching forward, reverse, neutral and parking), and a third speed for detecting the rotational speed of the secondary pulley 30b. Signals from a rotational speed sensor 55, a pedaling force sensor 56 that detects the pedaling force of the brake, a vehicle speed sensor 57 that detects the vehicle speed V, and an oil temperature sensor 58 that detects the oil temperature are input. The controller 10 controls various operations of the engine 1, the lockup clutch 2 a of the torque converter 2, and the automatic transmission 3 based on these input signals.

  The oil temperature sensor 58 detects the oil temperature in the torque converter 2. The oil temperature detected by the oil temperature sensor 58 (hereinafter, the actual oil temperature detected by the oil temperature sensor 58 is referred to as “actual oil temperature”) is transmitted to the controller 10 and stored in the controller 10. . When the detected actual oil temperature Tn becomes equal to or higher than the predetermined value T1, the controller 10 executes high oil temperature control that decreases the engine rotation speed and decreases the driving force. By restricting the driving force in this way, further increase in the oil temperature is suppressed and the automatic transmission 3 is protected.

  Next, a case where an abnormality has occurred in the oil temperature sensor 58 will be described.

  When the controller 10 detects that an abnormality has occurred in the oil temperature sensor 58, the controller 10 issues a warning in the passenger compartment. As a result, the driver recognizes that an abnormality has occurred in the oil temperature sensor 58, and prompts the driver to bring the car to the dealer.

  Further, when the controller 10 detects that an abnormality has occurred in the oil temperature sensor 58, the controller 10 estimates and controls the oil temperature by calculation (hereinafter, the oil temperature estimated by the controller 10 is referred to as "calculated oil temperature"). ). Then, when an abnormality occurs in the oil temperature sensor 58, the controller 10 uses the calculated oil temperature and executes high oil temperature control that restricts the driving force as necessary.

  Hereinafter, the high oil temperature control in the present embodiment will be specifically described with reference to FIG.

  FIG. 2 is a flowchart showing a flow of high oil temperature control according to the present embodiment. First, in step S <b> 1, the controller 10 determines whether an abnormality has occurred in the oil temperature sensor 58. As the abnormality of the oil temperature sensor 58, disconnection (when the output from the oil temperature sensor 58 becomes 0) or output abnormality (when an abnormally low temperature or high temperature is output) can be considered. If the controller 10 determines that an abnormality has occurred in the oil temperature sensor 58, the process proceeds to step S2, and if the controller 10 determines that the oil temperature sensor 58 is normal, the process proceeds to step S6.

  In step S2, an abnormality warning is generated. Specifically, when the controller 10 determines that an abnormality has occurred in the oil temperature sensor 58, the controller 10 turns on a warning lamp on the display unit in the vehicle interior. The warning may be a warning sound or a message.

  In step S3, the controller 10 calculates the calculated oil temperature Tca. If an abnormality occurs in the oil temperature sensor 58 as described above, the oil temperature cannot be detected by the oil temperature sensor 58. Therefore, the controller 10 calculates the calculated oil temperature Tca by calculation.

  Here, a specific method of calculating the calculated oil temperature Tca will be described with reference to FIG. FIG. 3 is a flowchart showing a method for calculating the calculated oil temperature Tca.

  In step S31, the actual oil temperature Tn is acquired. Specifically, the controller 10 acquires the actual oil temperature Tn immediately before the abnormality determination, in other words, the latest actual oil temperature Tn among the actual oil temperatures Tn detected when the normal determination is made.

  Next, in step S32, the heat generation amount Tg in the automatic transmission 3 is calculated. Specifically, the controller 10 controls the automatic transmission 3 based on a value related to the rotational speed of the automatic transmission 3 (for example, the input rotational speed, the output rotational speed, or the engine rotational speed of the automatic transmission). A calorific value Tg is calculated.

  In step S33, the heat dissipation amount Tr in the automatic transmission 3 is calculated. Specifically, the controller 10 calculates a heat dissipation amount Tr from the automatic transmission 3 based on a flow rate passing through an oil cooler (not shown), vehicle speed, hydraulic pressure, and the like.

  In step S34, the calculated oil temperature Tca is calculated. Specifically, the controller 10 calculates the calculated oil temperature Tca based on the latest actual oil temperature Tn acquired in step S31 and the temperature change based on the difference between the heat generation amount Tg and the heat release amount Tr.

  Returning to FIG. 2, in step S4, it is determined whether or not the calculated oil temperature Tca is equal to or higher than a predetermined value T1. Specifically, the controller 10 determines whether or not the calculated oil temperature Tca obtained in step S3 is equal to or greater than a predetermined value T1. If the calculated oil temperature Tca is equal to or higher than the predetermined value T1, the process proceeds to step S5. If the calculated oil temperature Tca is lower than the predetermined value T1, the process proceeds to END.

  In step S5, high oil temperature control is executed. Specifically, the driving force is regulated by reducing the engine speed. By restricting the driving force in this way (executing high oil temperature control), further increase in the oil temperature is suppressed. Therefore, the automatic transmission 3 can be protected.

  As a method for regulating the driving force, the vehicle speed and the engine torque may be reduced. Further, the degree of decrease in driving force may be changed according to the calculated oil temperature Tca.

  As described above, when the controller 10 determines in step S1 that the oil temperature sensor 58 is normal, the process proceeds to step S6. In step S6, it is determined whether the actual oil temperature Tn is equal to or higher than a predetermined value T2. Specifically, the controller 10 determines whether or not the actual oil temperature Tn detected by the oil temperature sensor 58 is equal to or higher than a predetermined value T2. If the actual oil temperature Tn is equal to or higher than the predetermined value T2, the process proceeds to step S5. If the actual oil temperature Tn is lower than the predetermined value T2, the process proceeds to END. Since the high oil temperature control in step S5 has been described above, the description thereof is omitted.

  The predetermined values T1 and T2 in the above embodiment may be different values or the same value.

  For example, when the controller 10 performs high oil temperature control so that the oil temperature is determined to be equal to or higher than T2 when an abnormality occurs in the oil temperature sensor 58, the actual oil temperature is not equal to or higher than T2. Nevertheless, high oil temperature control is executed. On the other hand, in the present embodiment, when the oil temperature sensor 58 is abnormal, it is possible to determine whether or not the high oil temperature control is necessary based on the calculated oil temperature Tca, and therefore it is not necessary to execute the high oil temperature control. It is possible to prevent the driving force from being restricted. In other words, since necessity of high oil temperature control is determined based on the calculated oil temperature Tca, excessive driving force regulation can be relaxed. Therefore, drivability can be prevented from being impaired for as long a time as possible when an abnormality occurs in the oil temperature sensor 58.

  By the way, the calculated oil temperature Tca calculated based on the heat generation amount Tg and the heat release amount Tr as described above may cause a deviation in the actual oil temperature Tn due to product variations and the like. Accordingly, it is conceivable to correct the calculated oil temperature Tca in order to improve the estimation accuracy of the calculated oil temperature Tca. Hereinafter, the correction value C used for this correction will be described with reference to FIGS. In the following description, the calculated oil temperature when the oil temperature sensor 58 is normal is distinguished as the calculated oil temperature Tcb, and the calculated oil temperature after the abnormality of the oil temperature sensor 58 is distinguished as the calculated oil temperature Tca.

  FIG. 4 is a flowchart showing a procedure for calculating the correction value C. In step S71, the actual oil temperature Tn is acquired. Specifically, the controller 10 acquires the actual oil temperature Tn detected by the oil temperature sensor 58 in a state where the oil temperature sensor 58 is operating normally.

  In step S72, the calculated oil temperature Tcb is calculated. The calculated oil temperature Tcb is an estimated value of the oil temperature when the oil temperature sensor 58 is operating normally. Specifically, the controller 10 is based on the actual oil temperature Tn when a predetermined time has elapsed after the ignition is turned on (for example, time t1 in FIG. 5) and the difference between the heat generation amount Tg and the heat release amount Tr. Calculated oil temperature Tcb. In addition, the calculation method of the emitted-heat amount Tg and the thermal radiation amount Tr is the same as that of step S31 and S32.

  In step S73, a difference ΔT is calculated. Specifically, the difference between the actual oil temperature Tn acquired in step S71 and the calculated oil temperature Tcb calculated in step S72 is calculated. The calculated ΔT is stored in the controller 10 as needed.

  In step S74, the correction value C is calculated and stored. Specifically, the controller 10 obtains the average value ΔTa of ΔT stored in step S73 and stores this average value ΔTa as the correction value C.

  ΔT corresponds to an error (deviation) between the actual oil temperature Tn and the calculated oil temperature Tcb. For this reason, when the abnormality of the oil temperature sensor 58 occurs, the estimation accuracy of the calculated oil temperature Tca can be improved by correcting the calculated oil temperature Tca using the previously calculated average value ΔTa of ΔT as the correction value C.

In the present embodiment, the controller 10 calculates and stores a correction value Cn (n = 1, 2, 3,...) For each predetermined range of engine speed. Specifically, for example, as shown in FIG. 5, when the engine speed is 0 to 1000 rpm, the actual oil temperature Tn is acquired at any time or at a predetermined interval, and the calculated oil temperature Tcb is calculated to calculate ΔT. And remember. Then, an average value ΔTa of the stored [Delta] T, the ΔTa engine rotational speed is stored as a correction value _{C 1} in the range of 0～1000Rpm (see FIG. 6). Further, the controller 10 calculates an average value ΔTa of ΔT even when the engine speed is in the range of 1001 to 2000 rpm, 2001 to 3000 rpm, and stores them as correction values C ₂ , correction values C ₃ , and so on ( (See FIG. 6).

  The magnitude of the error (ΔT) between the actual oil temperature Tn and the calculated oil temperature Tcb varies depending on the engine speed. Therefore, in this embodiment, the engine rotation speed is divided into predetermined ranges, and correction values Cn (n = 1, 2, 3,...) Are obtained for each predetermined range. The ranges shown in FIG. 5 and FIG. 6 show an example and can be set as appropriate.

  When an abnormality occurs in the oil temperature sensor 58, the engine speed Ne is detected by the first rotation speed sensor 51, and the calculated oil temperature Tca is corrected by the correction value Cn corresponding to the detected engine speed Ne. Thereby, the estimation accuracy of the calculated oil temperature Tca can be further improved.

  In the above embodiment, the correction value Cn is calculated for each predetermined range of the engine rotation speed. However, values related to the rotation speed of the automatic transmission 3 (for example, the input rotation speed, the output rotation speed of the automatic transmission 3, Alternatively, the vehicle speed or the like may be divided into predetermined ranges, and the correction value Cn may be calculated for each of these ranges. The engine rotation speed can also be converted into the rotation speed of the automatic transmission 3 from the gear ratio and the like, and thus is included in the value related to the rotation speed of the automatic transmission 3.

  The configuration, operation, and effect of the embodiment of the present invention configured as described above will be described together.

  The controller 10 controls the automatic transmission 3 having an oil temperature sensor 58 that detects the actual oil temperature Tn. Further, after the abnormality determination of the oil temperature sensor 58 is made, the controller 10 determines that the heat dissipation amount Tr of the automatic transmission 3 after the abnormality determination and the heat generation amount Tg of the automatic transmission 3 after the abnormality determination are normal. When the calculated oil temperature Tca of the automatic transmission 3 calculated based on the latest actual oil temperature Tn among the actual oil temperatures Tn becomes equal to or higher than a predetermined value T1, high oil temperature control for protecting the automatic transmission 3 is performed. It has a control part to execute.

  In this configuration, the oil temperature sensor 58 is determined based on the latest actual oil temperature Tn determined to be normal (actual oil temperature Tn immediately before occurrence of an abnormality in the oil temperature sensor 58), the heat release amount Tr, and the heat generation amount Tg. Estimate the oil temperature at the time of abnormality. In this configuration, when an abnormality occurs in the oil temperature sensor 58, the execution of the high oil temperature control is prohibited until the calculated oil temperature Tca exceeds the predetermined value T1, and therefore, until the vehicle is brought to the dealer. Driving force regulation is relaxed. Therefore, drivability can be prevented from being impaired as long as possible. When the calculated oil temperature Tca becomes equal to or higher than the predetermined value T1, the controller 10 (control unit) executes high oil temperature control. Thereby, the automatic transmission 3 can be sufficiently protected against the oil temperature rise. Furthermore, since the calculated oil temperature Tca is calculated using the latest actual oil temperature Tn (actual oil temperature Tn immediately before the abnormality of the oil temperature sensor 58), it is possible to keep the estimated accuracy of the calculated oil temperature Tca high. (Effects corresponding to claims 1 and 5).

  The controller 10 (control unit) executes high oil temperature control when the actual oil temperature Tn becomes equal to or higher than a predetermined value T2 when the oil temperature sensor 58 is determined to be normal.

  When the oil temperature sensor 58 is normal, highly accurate control is possible by using the oil temperature detected by the oil temperature sensor 58 (effect corresponding to claim 2).

  The controller 10 (control unit) uses the actual oil temperature Tn, the heat generation amount Tg of the automatic transmission 3 and the heat release amount Tr of the automatic transmission 3 to determine the correction value Cn of the calculated oil temperature Tca at the time of normality determination. In addition, after the abnormality determination, the correction oil temperature Tca is corrected using the correction value Cn.

  In the calculated oil temperature Tca using the heat generation amount Tg and the heat dissipation amount Tr, a deviation (error) may occur between the actual oil temperature Tn and the calculated oil temperature Tca due to problems such as product variations. Therefore, by learning the correction value Cn at the time of normality determination and using the correction value Cn learned at the time of abnormality determination, the influence of the deviation can be reduced after the abnormality determination of the oil temperature sensor 58 (claim). Effect corresponding to item 3).

  The controller 10 (control unit) sets different correction values Cn according to values related to the rotational speed of the automatic transmission 3 (engine rotational speed Ne, input rotational speed of the automatic transmission 3, output rotational speed, etc.).

  When the rotational speed changes, the magnitude of the deviation between the calculated oil temperature Tcb and the actual oil temperature Tn changes. For this reason, calculation is performed by setting a correction value Cn for each rotation speed (acquisition of a different correction value Cn according to the rotation speed when normal and correction with a different correction value Cn according to the rotation speed when abnormal). The accuracy of the oil temperature Tca can be improved (effect corresponding to claim 4).

  The embodiment of the present invention has been described above, but the above embodiment is merely a part of an application example of the present invention, and the technical scope of the present invention is limited to the specific configuration of the above embodiment. is not.

  The oil temperature sensor 58 detects the oil temperature in the torque converter 2, but any oil temperature may be used as long as the oil temperature is in the automatic transmission 3. Further, the oil temperature sensor 58 may be provided at a plurality of locations, and the high oil temperature control may be executed based on the oil temperature detected by each.

1 Engine (drive source)
3 Automatic transmission 5 Oil pump 10 Controller (control device, control unit)
30 CVT (continuously variable transmission mechanism)
51 First rotational speed sensor 58 Oil temperature sensor 100 Vehicle

Claims (5)

A transmission control device for controlling a transmission having an oil temperature sensor for detecting an actual oil temperature,
After the abnormality determination of the oil temperature sensor is made, the heat release amount of the transmission after the abnormality determination, the heat generation amount of the transmission after the abnormality determination, and the latest actual oil temperature determined normally And a control unit that executes high oil temperature control that protects the transmission when the calculated oil temperature of the transmission calculated based on the actual oil temperature exceeds a predetermined value. Control device. In the transmission control apparatus according to claim 1,
The control unit according to claim 1, wherein the control unit executes the high oil temperature control when the actual oil temperature becomes equal to or higher than a predetermined value when the oil temperature sensor is normal. In the transmission control device according to claim 1 or 2,
The control unit calculates a correction value for the calculated oil temperature using the actual oil temperature, the heat generation amount of the transmission, and the heat dissipation amount of the transmission, and the abnormality After the determination, the transmission control apparatus corrects the calculated oil temperature using the correction value. In the transmission control device according to claim 3,
The control unit according to claim 1, wherein the control unit sets the different correction value according to a value related to a rotation speed of the transmission. A transmission control method for controlling a transmission having an oil temperature sensor for detecting an actual oil temperature,
After the abnormality determination of the oil temperature sensor is made, the heat release amount of the transmission after the abnormality determination, the heat generation amount of the transmission after the abnormality determination, and the latest actual oil temperature determined normally And a high oil temperature control that protects the transmission when the calculated oil temperature of the transmission calculated based on the actual oil temperature exceeds a predetermined value.

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