Vehicle control device

Abstract

To provide a control device for a vehicle capable of switching to a parking position when a power supply failure state occurs during a switching transition from a non-parking position to the parking position.SOLUTION: In the case where a power supply failure state occurs during a switching transition from a non-parking position to a parking position, an abnormal state of an electric actuator due to stagnation of the drive of the electric actuator for a predetermined time or longer is not detected until a time when a power supply to the electric actuator is switched to a second power supply. Thereby, since a fail-safe operation is not performed when a power supply failure of a first power supply is determined during the occurrence of the power supply failure state, and the power supply to the electric actuator is switched to the second power supply, re-driving of the electric actuator is supposed to be possible. Therefore, when the power supply failure state occurs during the switching transition from the non-parking position to the parking position, switching to the parking position becomes possible.SELECTED DRAWING: Figure 3

Description

[Technical Field]

[0001] The present invention relates to a control device for a vehicle equipped with a switching device that switches the shift position of a power transmission device by operating an electric actuator. [Background technology]

[0002] A well-known vehicle control device includes a switching device that switches the shift position of a power transmission device that transmits power from a power source to drive wheels by operating an electric actuator, a first power source that supplies power to drive the electric actuator, and a second power source that supplies power to drive the electric actuator during a power failure state in which power to drive the electric actuator is not supplied from the first power source. For example, a vehicle CPU is described in Patent Document 1. Patent Document 1 discloses that when a power failure of a battery corresponding to the first power source is detected and a driver issues a shift command to switch the shift range to parking range, the CPU starts supplying power to a shift control unit from a backup power source corresponding to the second power source and commands the shift control unit to transition to parking range. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Publication No. 2018-13136 Summary of the Invention [Problem to be solved by the invention]

[0004] Here, the vehicle control device controls the shift position between a parking position, in which a rotating member that rotates together with the drive wheels is mechanically fixed so as not to rotate, and a non-parking position other than the parking position. If an abnormal state of the electric actuator is detected because drive of the electric actuator has stagnated for a predetermined period of time or longer during a transition between the parking position and the non-parking position, a fail-safe operation may be performed to disable restarting of the electric actuator. Furthermore, if a power failure of the first power source is determined during a power failure state, the power supply to the electric actuator may be switched to the second power source. However, if a power failure state occurs during switching from the non-parking position to the parking position, the drive of the electric actuator is stopped. At this time, if an abnormal state of the electric actuator is detected before a power failure of the first power source is determined and the power supply to the electric actuator is switched to the second power source, the fail-safe operation disables restarting of the electric actuator. In this case, even if the power supply is switched to the second power source, restarting the electric actuator to switch to the parking position may be disabled.

[0005] The present invention has been made against the background of the above circumstances, and its purpose is to provide a vehicle control device that can switch to the parking position when a power failure occurs during the transition from a non-parking position to the parking position. [Means for solving the problem]

[0006] The gist of a first aspect of the present invention is a control device for a vehicle including: (a) a switching device that switches a shift position of a power transmission device that transmits power from a power source to drive wheels by operating an electric actuator; a first power source that supplies power to drive the electric actuator; and a second power source that supplies power to drive the electric actuator during a power failure state in which power to drive the electric actuator is not supplied from the first power source; (b) a shift control unit that controls switching of the shift position between a parking position in which a rotating member that rotates together with the drive wheels is mechanically fixed so as not to rotate, and a non-parking position other than the parking position; and (c) a shift control unit that controls switching of the shift position between the parking position and the non-parking position during a switching transition between the parking position and the non-parking position. (d) a power supply control unit that switches the power supply to the electric actuator to the second power supply when it determines that the first power supply has failed during the power supply failure state; and (e) an abnormality detection stopping unit that, when the power supply failure state occurs during the transition from the non-parking position to the parking position, does not allow the fail-safe unit to detect the abnormal state of the electric actuator until the power supply control unit switches the power supply to the electric actuator to the second power supply.

[0007] Further, a second invention is a vehicle control device according to the first invention, wherein the power supply control unit determines that the power supply failure state has occurred when the voltage of the first power supply becomes equal to or lower than a predetermined voltage, and determines that the power supply failure has occurred when the occurrence of the power supply failure state has continued for a predetermined power supply failure determination time or longer, which is a value longer than the predetermined time, and determines that the first power supply has experienced a temporary power supply failure when the occurrence of the power supply failure state has continued for a predetermined temporary power supply failure determination time or longer, which is a value shorter than the predetermined time, and the abnormality detection stop unit does not allow the fail-safe unit to detect an abnormal state of the electric actuator from the time the temporary power supply failure is determined by the power supply control unit until the power supply failure is determined and the power supply to the electric actuator is switched to the second power supply.

[0008] In addition, a third invention is that in the vehicle control device described in the second invention, the specified voltage is pre-determined to a higher value when determining the temporary power supply failure than when determining the power supply failure.

[0009] Further, a fourth invention is a vehicle control device according to the first invention, wherein the fail-safe unit performs the fail-safe operation if the power supply failure state occurs when the first power supply is being used by the power supply control unit to supply power to the electric actuator, and the abnormality detection stop unit causes the power supply control unit to stop using the first power supply until the power supply to the electric actuator is switched to the second power supply when the power supply failure state occurs during a transition from the non-parking position to the parking position.

[0010] A fifth invention is a vehicle control device according to any one of the first to fourth inventions, wherein when the power supply to the electric actuator is switched to the second power supply by the power supply control unit when the power supply failure state occurs during a transition from the non-parking position to the parking position, the shift control unit re-drives the electric actuator to switch to the parking position.

[0011] A sixth aspect of the present invention is the vehicle control device according to the fifth aspect of the present invention, wherein when the shift control unit restarts the electric actuator, it calculates the amount of drive to the parking position using drive information of the electric actuator at the time when drive of the electric actuator stagnated due to the occurrence of the power supply failure state and operation information of the electric actuator during the transient period when drive of the electric actuator stagnated. [Effects of the Invention]

[0012] According to the first aspect of the present invention, when a power failure occurs during a transition from a non-parking position to a parking position, an abnormal state of the electric actuator caused by the drive of the electric actuator halting for a predetermined time or longer is not detected until the power supply to the electric actuator is switched to the second power source. As a result, when a power failure of the first power source is determined during a power failure state and the power supply to the electric actuator is switched to the second power source, a fail-safe operation is not performed, and the electric actuator can be re-driven. Therefore, when a power failure occurs during a transition from a non-parking position to a parking position, it is possible to switch to the parking position.

[0013] According to the second aspect of the present invention, a temporary power failure of the first power source is determined when the occurrence of a power failure state continues for at least a predetermined temporary power source failure determination time, which is shorter than the predetermined time used to detect an abnormal state of the electric actuator. Furthermore, the abnormal state of the electric actuator is not detected from the time when the temporary power source failure is determined until the power supply to the electric actuator is switched to the second power source. As a result, the temporary power source failure of the first power source is determined earlier than the detection of the abnormal state of the electric actuator, and therefore the fail-safe operation is not reliably performed when the power supply to the electric actuator is switched to the second power source.

[0014] According to the third aspect of the present invention, the predetermined voltage for determining the occurrence of a power failure state of the first power source is set to a higher value when determining a temporary power failure than when determining a power failure, thereby determining a temporary power failure of the first power source at an earlier timing than when an abnormal state of the electric actuator is detected, thereby widening the range in which an abnormal state of the electric actuator cannot be detected.

[0015] According to the fourth aspect of the present invention, if a power failure occurs during a transition from a non-parking position to a parking position, the use of the first power source is stopped until the power supply to the electric actuator is switched to the second power source, thereby preventing a fail-safe operation caused by the power failure occurring when the first power source is being used to supply power to the electric actuator.

[0016] According to the fifth aspect of the present invention, if a power failure occurs during a transition from a non-parking position to a parking position and the power supply to the electric actuator is switched to the second power source, the electric actuator is re-driven to switch to the parking position. As a result, the electric actuator is switched to the parking position after the power supply to the electric actuator has been switched to the second power source.

[0017] According to the sixth aspect of the present invention, when the electric actuator is restarted, the drive amount to the parking position is calculated using the drive information of the electric actuator at the time when the drive of the electric actuator stagnated due to the occurrence of a power supply failure and the operation information of the electric actuator during the transient period when the drive of the electric actuator stagnated. This makes it possible to appropriately drive the electric actuator so as to switch to the parking position after the power supply to the electric actuator is switched to the second power source. [Brief explanation of the drawings]

[0018] [Figure 1] 1 is a diagram illustrating a schematic configuration of a vehicle to which the present invention is applied, and is also a diagram illustrating main parts of control functions and control systems for various controls in the vehicle. [Figure 2] FIG. 2 is a diagram illustrating the configuration of a control system related to an SBW ECU. [Figure 3] 1 is a flowchart illustrating the main control operations of an electronic control device, and is a flowchart illustrating the control operations for enabling switching to the P position when a power failure occurs during a transition from a non-P position to a P position. [Figure 4] 4 is a diagram showing an example of a time chart when the control operation shown in the flowchart of FIG. 3 is executed. FIG. DETAILED DESCRIPTION OF THE INVENTION

[0019] In an embodiment of the present invention, the power source is, for example, an engine that generates power by burning fuel. The vehicle may also be equipped with an electric motor or the like as the power source in addition to or instead of the engine.

[0020] The power transmission device includes, for example, an automatic transmission, such as a known planetary gear automatic transmission, a known belt-type continuously variable transmission, a known synchronous mesh parallel two-shaft automatic transmission, a known DCT (Dual Clutch Transmission), a known electric continuously variable transmission, or a known transmission in which an electric continuously variable transmission and a planetary gear automatic transmission are arranged in series.

[0021] Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. [Example]

[0022] Fig. 1 is a diagram illustrating the schematic configuration of a vehicle 10 to which the present invention is applied. Fig. 1 also illustrates the main parts of the control functions and control systems for various controls in the vehicle 10. In Fig. 1, the vehicle 10 is equipped with an engine 12 as a power source, drive wheels 14, and a power transmission device 16 that transmits power from the engine 12 to the drive wheels 14.

[0023] The engine torque Te of the engine 12 is controlled by an engine control device 30, which includes a throttle actuator, a fuel injection device, an ignition device, etc., provided on the vehicle 10, being controlled by an electronic control device 90, which will be described later.

[0024] The power transmission device 16 includes an automatic transmission 18, a propeller shaft 22 connected to an output shaft 20 of the automatic transmission 18, a differential 24 connected to the propeller shaft 22, left and right drive shafts 26 connected to the differential 24, etc. In the power transmission device 16, power output from the engine 12 is transmitted to the automatic transmission 18 connected to the engine 12, and then transmitted from the automatic transmission 18 to the drive wheels 14 via the propeller shaft 22, the differential 24, the drive shafts 26, etc.

[0025] The automatic transmission 18 performs gear shifting in accordance with the accelerator opening θacc, vehicle speed V, etc. by operating a hydraulic actuator in the automatic transmission 18 using hydraulic pressure output from a hydraulic control circuit 40 provided in the vehicle 10. The hydraulic control circuit 40 adjusts the hydraulic pressure output to the automatic transmission 18 by being controlled by an electronic control device 90, which will be described later.

[0026] The vehicle 10 further includes a shift operation device 50, a shift-by-wire device 60, a first power source 70, etc. In the vehicle 10, the shift position (=shift position) POSsh of the automatic transmission 18 is changed using a shift-by-wire system. In this embodiment, shift-by-wire is also referred to as SBW. The shift position POSsh of the automatic transmission 18 is the same as the shift range of the automatic transmission 18.

[0027] The shift operation device 50 is an operation device for manually selecting one of multiple shift positions POSsh in the automatic transmission 18. In other words, the shift operation device 50 is an operation device that is manually operated to accept a request to change the shift position POSsh of the automatic transmission 18. The shift operation device 50 is operated by the driver to an operation position (=operation position) POSop that corresponds to the shift position POSsh of the automatic transmission 18. The operation position POSop includes, for example, P, R, N, D, and M operation positions. The shift position POSsh of the automatic transmission 18 is the same as the shift position of the power transmission device 16.

[0028] The P operating position is a parking operating position for selecting a parking position of the automatic transmission 18. In this embodiment, the parking position is referred to as the P position (=P position). The P position of the automatic transmission 18 is a shift position POSsh in which the power transmission device 16, i.e., the automatic transmission 18, is in a neutral state and rotation of the output shaft 20, which is a rotating member that rotates together with the drive wheels 14, is mechanically prevented. The neutral state of the automatic transmission 18 is a state in which power transmission in the automatic transmission 18 is cut off, that is, a state in which the automatic transmission 18 is unable to transmit power. The state in which rotation of the output shaft 20 is mechanically prevented is a state in which the output shaft 20 is mechanically fixed so as not to rotate, and is a parking lock (=P lock) state of the automatic transmission 18. The output shaft 20 is mechanically fixed so as not to rotate by a shift-by-wire device (=SBW device) 60.

[0029] The R operating position is a reverse driving operating position that selects a reverse driving position (= reverse driving position) of the automatic transmission 18 that enables the vehicle 10 to drive in reverse. In this embodiment, the reverse driving position is referred to as the R position (= R position). The N operating position is a neutral operating position that selects a neutral position (= neutral position) of the automatic transmission 18 in which the automatic transmission 18 is in a neutral state. In this embodiment, the neutral position is referred to as the N position (= N position). The D operating position is a forward driving operating position that selects a forward driving position (= forward driving position) of the automatic transmission 18 that enables the vehicle 10 to drive in forward. In this embodiment, the forward driving position is referred to as the D position (= D position). The M operating position is a manual shift operating position that selects a manual shift position (= manual shift position) of the automatic transmission 18 that enables manual shifting in a state that enables the vehicle 10 to drive in forward. Manual shifting is a shifting method in which the driver operates a paddle switch or the like to change the speed of the automatic transmission 18. In this embodiment, the manual shift position is referred to as the M position.

[0030] The R, N, D, and M positions of the automatic transmission 18 are all shift positions POSsh in which rotation of the output shaft 20 is permitted, and are non-P positions (=non-parking positions) other than the P position of the automatic transmission 18. The R, N, D, and M operating positions are all non-P operating positions (=non-parking operating positions) that select the non-P position of the automatic transmission 18. The state in which rotation of the output shaft 20 is permitted is a state in which the mechanical fixation of the output shaft 20 is released, that is, a state in which the P lock state of the automatic transmission 18 is released, and a non-parking lock (=non-P lock) state of the automatic transmission 18.

[0031] The shift operation device 50 has an operator that is selectively operated by the driver to a plurality of operating positions POSop corresponding to the plurality of shift positions POSsh of the automatic transmission 18. These operators are, for example, a shift lever 52 and a P switch 54. The P switch 54 is an operator provided separately from the shift lever 52. The operating position POSop of the shift lever 52 is the lever position (= lever position) Plev, and the operating position POSop of the P switch 54 is the P switch-on position (= P switch-on position) Psw. Both the shift lever 52 and the P switch 54 are momentary-type operators that return to their original positions when no external force is applied. In this embodiment, this original position is referred to as the home position (= home position) POSopH. The shift operation device 50 includes, as its operating positions POSop, the home position POSopH to which it returns when not operated by the driver.

[0032] The shift lever 52 is selectively operated by the driver to a lever position Plev corresponding to the desired shift position POSsh in order to set the shift position POSsh of the automatic transmission 18 to a desired one of a plurality of non-P positions. The P switch 54 is operated by the driver to set the shift position POSsh of the automatic transmission 18 to the P position.

[0033] The lever position Plev of the shift lever 52 is, for example, the R operating position, the N operating position, the D operating position, the H operating position, and the M operating position (see R, N, D, H, and M in FIG. 1). The H operating position is the home position POSopH of the shift lever 52. Even if the shift lever 52 has been operated to a lever position Plev other than the H operating position, if the driver releases the shift lever 52, the shift lever 52 will be returned to the H operating position by a mechanical mechanism such as a spring.

[0034] The shift operation device 50 is equipped with a lever position sensor 56 that detects the lever position Plev. The lever position sensor 56 is a sensor that outputs a lever position signal Splev corresponding to the lever position Plev to an electronic control device 90 (described later). The electronic control device 90 determines the lever position Plev based on the lever position signal Splev. This detects operation to the R, N, D, or M operating position. An operation to the R, N, D, or M operating position is a shift operation for switching the shift position POSsh of the automatic transmission 18 to one of the R, N, D, or M positions, that is, a shift operation for switching to a non-P position, and is also referred to as a shift lever operation.

[0035] The P switch 54 is, for example, a momentary push button switch that is pressed by the driver to a P operating position, which is the P switch on position Psw. The position of the P switch 54 when not pressed is the home position POSopH of the P switch 54. Even if the P switch 54 is pressed to the P operating position, if the driver releases the P switch 54, the P switch 54 is returned to the home position POSopH by a mechanical mechanism such as a spring. The P switch 54 is a sensor that outputs a P switch signal Spsw corresponding to the P operating position to the electronic control unit 90 (described later) each time the P switch 54 is pressed to the P operating position. The electronic control unit 90 determines the P switch on position Psw based on the P switch signal Spsw. This detects operation to the P operating position. Operation to the P operating position is a shift operation to switch the shift position POSsh of the automatic transmission 18 to the P position, and is also referred to as a P switch operation.

[0036] The lever position signal Splev and the P switch signal Spsw are position signals Sposop corresponding to the operation position POSop. The P switch 54 and the lever position sensor 56 are operation position sensors 58 that output the position signal Sposop. The shift lever operation and the P switch operation by the driver are shift operations in the shift operation device 50 for switching the shift position of the automatic transmission 18.

[0037] The SBW device 60 includes an electric actuator 61, a rotation angle sensor 62, a parking lock mechanism 64, and the like. The electric actuator 61 is, for example, a motor. In this embodiment, the electric actuator is also referred to as an ACT. The rotation angle sensor 62 is two Hall ICs that detect the rotation angle of a rotor provided in the electric actuator 61. The rotation angle of the rotor corresponds to an ACT position POSact, which is the operating position of the electric actuator 61. The rotation angle sensor 62 is a sensor that detects the relative position of the ACT position POSact, and outputs an ACT position signal Sposact as a count value corresponding to the ACT position POSact to an electronic control device 90, which will be described later.

[0038] The parking lock mechanism 64 includes a parking lock gear 66, a parking lock pole 67, a cam 68, a parking rod 69, etc. The parking lock gear 66 is a member provided to rotate integrally with the output shaft 20. The parking lock pole 67 has claws that mesh with the gear teeth of the parking lock gear 66, and is a member that can mesh with the parking lock gear 66. The cam 68 is provided at the tip of the parking rod 69 on the parking lock pole 67 side. The cam 68 is a tapered member that is moved toward the parking lock pole 67 to cause the parking lock pole 67 to mesh with the parking lock gear 66. The parking rod 69 is a member that supports the cam 68 at one end, and is mechanically connected at the other end to the electric actuator 61 via a member (not shown).

[0039] The electric actuator 61 is operated based on a P-switching control command signal Splock from an electronic control device 90 (described later). The P-switching control command signal Splock is a control command signal for controlling switching between the P position and the non-P position, and is output from the electronic control device 90 based on a position signal Sposop corresponding to the operation position POSop. The SBW device 60 is a P-lock device that switches between a P-lock state and a non-P-lock state by the operation of the electric actuator 61, and switches the shift position POSsh of the automatic transmission 18 between the P position and the non-P position. For example, when a P switch operation of the P switch 54 is detected, the electric actuator 61 is controlled by the electronic control device 90 to operate the parking rod 69 and the cam 68 so that the cam 68 is biased toward the parking lock pole 67. As a result, the parking lock pole 67 is moved toward the parking lock gear 66. When the parking lock pole 67 is moved to a position where it meshes with the parking lock gear 66, the output shaft 20 is fixed so as to be unable to rotate together with the parking lock gear 66, and the drive wheels 14 which rotate in conjunction with the output shaft 20 are fixed so as to be unable to rotate.

[0040] In this way, the SBW device 60 is a switching device that performs shift switching by switching the shift position POSsh of the automatic transmission 18 based on the P switching control command signal Splock through the operation of the electric actuator 61. Therefore, the operation of the shift lever or P switch by the driver is also a shift switching operation that causes the SBW device 60 to perform shift switching.

[0041] The first power source 70 is, for example, a known auxiliary battery that applies a predetermined voltage to each of the shift operation device 50, the SBW device 60, the electronic control device 90 (described later), etc. For example, the first power source 70 supplies power to drive the electric actuator 61. The first power source 70 also supplies power to an SBW ECU 96 provided in the electronic control device 90 (see FIG. 2 (described later)). The first power source 70 also applies a voltage to the operation position sensor 58 for outputting a position signal Sposop corresponding to the operation position POSop.

[0042] The vehicle 10 is equipped with an electronic control unit 90 as a controller including a control device for the vehicle 10. The electronic control unit 90 is configured to include a so-called microcomputer equipped with, for example, a CPU, RAM, ROM, an input / output interface, etc. The CPU executes various controls of the vehicle 10 by utilizing the temporary storage function of the RAM and performing signal processing in accordance with programs previously stored in the ROM. For example, the electronic control unit 90 executes output control of the engine 12, shift control of the automatic transmission 18, and switching control of the shift position POSsh by the SBW device 60. For these purposes, the electronic control unit 90 includes an engine ECU 92 which is an electronic control unit for engine control, a transmission ECU 94 which is an electronic control unit for transmission control, an SBW ECU 96 which is an electronic control unit for SBW control, etc.

[0043] The electronic control device 90 is supplied with various signals (e.g., P switch signal Spsw, lever position signal Splev, ACT position signal Sposact, engine rotation speed Ne, output rotation speed No corresponding to vehicle speed V, accelerator opening θacc, brake-on signal Bon, first power supply voltage Vbat1 which is the voltage of the first power supply 70, etc.) based on detection values ​​from various sensors provided on the vehicle 10 (e.g., P switch 54, lever position sensor 56, rotation angle sensor 62, engine rotation speed sensor 80, output rotation speed sensor 82, accelerator opening sensor 84, brake switch 86, battery sensor 88, etc.).

[0044] The electronic control unit 90 outputs various command signals (e.g., engine control command signal Se, transmission control command signal Sat, P switching control command signal Splock, etc.) to each device (e.g., engine control unit 30, hydraulic control circuit 40, SBW device 60, etc.) provided in the vehicle 10.

[0045] The engine ECU 92 calculates the amount of driving demand made by the driver for the vehicle 10, for example, by applying the accelerator opening θacc and the vehicle speed V to a driving demand map. The driving demand map is a relationship that is experimentally or design-based and stored in advance, i.e., a predetermined relationship. The driving demand is, for example, a required driving torque Trdem at the drive wheels 14. The engine ECU 92 outputs an engine control command signal Se to the engine control device 30 to control the engine 12 so as to obtain an engine torque Te that realizes the required driving torque Trdem, taking into account the gear ratio of the automatic transmission 18, etc. The required driving torque Trdem [Nm] can be viewed from another perspective as a required driving power Prdem [W] at the vehicle speed V at that time. The required driving force Frdem [N] at the drive wheels 14, etc., can also be used as the driving demand.

[0046] The transmission ECU 94 determines whether to shift the automatic transmission 18 using, for example, a shift map, which is a predetermined relationship, and outputs a transmission control command signal Sat to the hydraulic control circuit 40 as needed to execute shift control of the automatic transmission 18. The shift map is a predetermined relationship having shift lines for determining whether to shift the automatic transmission 18 on a two-dimensional coordinate system using, for example, vehicle speed V and accelerator opening θacc as variables.

[0047] The SBW ECU 96 outputs a P switching control command signal Splock to the SBW device 60 and outputs a shift position command signal Spossh to the transmission ECU 94 so as to switch the shift position POSsh of the automatic transmission 18 based on the operating position POSop of the shift operating device 50.

[0048] FIG. 2 is a diagram illustrating an example of the configuration of a control system related to the SBW ECU 96. In FIG. 2, the vehicle 10 employs a sub-battery system so that the shift position POSsh of the automatic transmission 18 can be switched to the P position even when the voltage of the first power source 70 drops. For this reason, the vehicle 10 is equipped with a second power source 72 as a sub-battery connected in parallel with the first power source 70. The second power source 72 receives power from the first power source 70 via, for example, a relay (not shown). The second power source 72 is, for example, a nickel-metal hydride battery or a capacitor. Like the first power source 70, the second power source 72 supplies power to the SBW ECU 96.

[0049] The vehicle 10 is equipped with a first relay 74 and a second relay 76. The first relay 74 opens and closes a power supply circuit between the first power supply 70 and the electric actuator 61 in the SBW device 60. The first relay 74 is turned on by electrical connection with the SBW ECU 96, and supplies power from the first power supply 70 to the electric actuator 61. The second relay 76 opens and closes a power supply circuit between the second power supply 72 and the electric actuator 61. The second relay 76 is turned on by electrical connection with the SBW ECU 96, and supplies power from the second power supply 72 to the electric actuator 61. The second power supply 72 supplies power to drive the electric actuator 61 during a power failure state in which power to drive the electric actuator 61 is not supplied from the first power supply 70.

[0050] The SBW ECU 96 includes a shift control means, that is, a shift control section 96a, a fail-safe means, that is, a fail-safe section 96b, and a power supply control means, that is, a power supply control section 96c.

[0051] The shift control unit 96a determines a shift operation by the driver using the shift operation device 50 based on the position signal Sposop, and sets a target position corresponding to the operation position POSop. The shift control unit 96a outputs a switch request (P switch control command signal Splock, shift position command signal Spossh) to switch the automatic transmission 18 to the shift position POSsh corresponding to the target position. For example, the shift control unit 96a controls the switching of the shift position POSsh between the P position and a non-P position.

[0052] If the shift control unit 96a detects input of the P switch signal Spsw when the shift position POSsh is in a non-P position, it sets the P position as the target position. The shift control unit 96a outputs a P lock command to the SBW device 60 as a P switch control command signal Splock for switching the automatic transmission 18 to the P position. The SBW device 60 switches the automatic transmission 18 to the P lock state by operating the electric actuator 61. In addition, the shift control unit 96a outputs a shift position command signal Spossh to the transmission ECU 94 for placing the automatic transmission 18 in neutral. The transmission ECU 94 outputs a transmission control command signal Sat to the hydraulic control circuit 40 for placing the automatic transmission 18 in neutral.

[0053] On the other hand, if the shift control unit 96a detects input of the lever position signal Splev when the shift position POSsh is in the P position, it sets the non-P position as the target position. The shift control unit 96a outputs a P-switching control command signal Splock to the SBW device 60 to switch the automatic transmission 18 to the non-P position. The SBW device 60 operates the electric actuator 61 to switch the automatic transmission 18 to the non-P lock state. In addition, the shift control unit 96a sets the shift position POSsh to one of the R position, N position, or D position corresponding to the lever position signal Splev as the target position. The shift control unit 96a outputs a shift position command signal Spossh to the transmission ECU 94 to switch to the set shift position POSsh. The transmission ECU 94 outputs a transmission control command signal Sat to the hydraulic control circuit 40 to switch the automatic transmission 18 to the shift position POSsh corresponding to the shift position command signal Spossh.

[0054] The fail-safe unit 96b determines whether the drive of the electric actuator 61 has stagnated for a predetermined time TMf or more during a transition between the P position and the non-P position. For example, the fail-safe unit 96b determines whether the drive of the electric actuator 61 has stagnated for a predetermined time TMf or more based on whether a state in which the change in the ACT position signal Sposact from the rotation angle sensor 62 is smaller than a predetermined change continues for a predetermined time TMf or more. The predetermined change is, for example, a predetermined threshold value for determining that the drive of the electric actuator 61 has stagnated. If the fail-safe unit 96b determines that the drive of the electric actuator 61 has stagnated for a predetermined time TMf or more, it detects an abnormal state of the electric actuator 61. The predetermined time TMf is a predetermined threshold value for determining that the electric actuator 61 is in an abnormal state. If the fail-safe unit 96b detects an abnormal state of the electric actuator 61, it performs a fail-safe operation FS, which disables the electric actuator 61 from being driven again.

[0055] If the power supply control unit 96c determines that the first power supply 70 has failed during a power failure state, it switches the power supply to the electric actuator 61 to the second power supply 72. For example, the power supply control unit 96c determines whether a power failure state has occurred in the first power supply 70 based on whether the first power supply voltage Vbat1 is equal to or lower than a predetermined voltage Vbatf. The predetermined voltage Vbatf is, for example, a predetermined threshold value for determining whether the first power supply 70 has failed. The power supply control unit 96c determines whether the power failure state has continued for a power failure determination time Tmlps or more. If the power failure state has continued for the power failure determination time Tmlps or more, the power supply control unit 96c determines that the first power supply 70 has failed. The power failure determination time Tmlps is, for example, a predetermined threshold value for reliably determining that the first power supply 70 has failed. The power failure determination time Tmlps is, for example, a predetermined value longer than the predetermined time TMf. The power supply control unit 96c switches the power supply to the electric actuator 61 from the second power supply 72 by switching from energizing the first relay 74 to energizing the second relay 76.

[0056] If a power failure occurs in the first power source 70 during the transition of driving the electric actuator 61 to change the shift position POSsh from the non-P position to the P position, the driving of the electric actuator 61 will stagnate. In this case, because the power failure determination time TMlps is longer than the predetermined time TMf, an abnormal state of the electric actuator 61 will be detected before the power failure of the first power source 70 is determined. In this case, even if the power supply to the electric actuator 61 is switched to the second power source 72, the fail-safe operation FS will prevent the electric actuator 61 from being driven again. Therefore, the shift position POSsh cannot be switched to the P position.

[0057] Therefore, the SBW ECU 96 further includes an abnormality detection stopping means, that is, an abnormality detection stopping unit 96d.

[0058] When the power supply control unit 96c determines that a power failure state has occurred in the first power supply 70 during the transition from the non-P position to the P position, the abnormality detection stopping unit 96d prevents the fail-safe unit 96b from detecting an abnormal state of the electric actuator 61 until the power supply control unit 96c switches the power supply to the electric actuator 61 to the second power supply 72.

[0059] For example, the power supply control unit 96c determines whether the occurrence of a power supply failure state continues for a temporary power supply failure determination time TMlpsp or longer. If the occurrence of a power supply failure state continues for a temporary power supply failure determination time TMlpsp or longer, the power supply control unit 96c determines that the first power supply 70 has experienced a temporary power supply failure. The temporary power supply failure determination time TMlpsp is, for example, predetermined to a value shorter than the predetermined time TMf. This allows the temporary power supply failure to be determined earlier than the detection of the abnormal state if the abnormal state of the electric actuator 61 is caused by the occurrence of a power supply failure state in the first power supply 70. The abnormality detection stop unit 96d does not allow the fail-safe unit 96b to detect the abnormal state of the electric actuator 61 from the time the power supply control unit 96c determines a temporary power supply failure until the power supply failure is determined and the power supply to the electric actuator 61 is switched to the second power supply 72. Not detecting the abnormal state of the electric actuator 61 is equivalent to concealing, or masking, the abnormality of the electric actuator 61. As a result, when the power supply to the electric actuator 61 is switched to the second power source 72, the fail-safe operation FS is not performed, and the electric actuator 61 can be driven again.

[0060] When the power supply control unit 96c determines that a power failure state has occurred in the first power source 70 during the transition from the non-P position to the P position, and the power supply to the electric actuator 61 is switched to the second power source 72 by the power supply control unit 96c, the shift control unit 96a re-drives the electric actuator 61 to switch to the P position.

[0061] When restarting the electric actuator 61, the shift control unit 96a resets the target position for setting the shift position POSsh to the P position and drives the electric actuator 61 to a position where the automatic transmission 18 is reliably placed in the P-lock state. For example, the shift control unit 96a stores the position signal Sposop at the time when the drive of the electric actuator 61 is stalled due to the occurrence of a power failure as drive information of the electric actuator 61. Also, when the drive of the electric actuator 61 is stalled due to the occurrence of a power failure, the electric actuator 61 is in a free state. Therefore, the shift control unit 96a stores a change in the position signal Sposop during the free state as operation information of the electric actuator 61 during a transient period when the drive of the electric actuator 61 is stalled. When restarting the electric actuator 61, the shift control unit 96a resets the target position for setting the electric actuator 61 to the P position using the position signal Sposop at the time when the drive of the electric actuator 61 is stalled and the change in the position signal Sposop during the free state. Resetting the target position to set the P position also means calculating the amount of drive to the P position, that is, the amount of change in the position signal Sposop.

[0062] Here, the fail-safe unit 96b may perform fail-safe operation FS if a power failure state occurs when the first power source 70 is being used by the power source control unit 96c to supply power to the electric actuator 61. However, in this case, even if an abnormality in the electric actuator 61 is masked, the fail-safe operation FS caused by the power failure state prevents the electric actuator 61 from being re-driven. As a result, when the power supply to the electric actuator 61 is switched to the second power source 72, the electric actuator 61 is prevented from being re-driven. Therefore, when the power source control unit 96c determines that a power failure state has occurred in the first power source 70 during the transition from the non-P position to the P position, the abnormality detection stop unit 96d causes the power source control unit 96c to stop use of the first power source 70 until the power supply to the electric actuator 61 is switched to the second power source 72. The abnormality detection stop unit 96d causes the power source control unit 96c to stop power supply to the first relay 74, thereby stopping use of the first power source 70. As a result, the fail-safe operation FS caused by the occurrence of a power supply failure state is not performed. When the use of the first power source 70 is stopped until the power supply to the electric actuator 61 is switched to the second power source 72, the power supply to the second relay 76 is also stopped, and the use of the second power source 72 is also stopped. Therefore, the abnormality detection stopping unit 96d stops the switching control of the shift position POSsh by the electric actuator 61.

[0063] If a temporary power failure of the first power source 70 can be determined at an earlier timing, the ability to mask an abnormality in the electric actuator 61 can be improved. A power failure or temporary power failure of the first power source 70 is determined based on the length of time that the power failure state continues to occur. If the occurrence of a power failure state is determined at an earlier timing, a temporary power failure of the first power source 70 can be determined at an earlier timing. Therefore, the predetermined voltage Vbatf for determining the occurrence of a power failure state of the first power source 70 may be set in advance to a higher value when determining a temporary power failure than when determining a power failure.

[0064] FIG. 3 is a flowchart illustrating the main control operations of the electronic control device 90, which are for enabling switching to the P position when a power failure occurs during the transition from the non-P position to the P position, and is executed repeatedly when a P lock command is output, for example.

[0065] 3, first, in step S10 (hereinafter, the term "step" will be omitted) corresponding to the function of the shift control unit 96a, the electric actuator 61 is started to be driven to switch the shift position POSsh from the non-P position to the P position. Next, in step S20 corresponding to the function of the fail-safe unit 96b, it is determined whether the electric actuator 61 is operating as expected based on a change in the ACT position signal Sposact from the rotation angle sensor 62. If the determination in step S20 is negative, in step S30 corresponding to the function of the power supply control unit 96c, it is determined whether or not there is a temporary power failure of the first power supply 70. If the determination in step S30 is negative, in step S40 corresponding to the function of the fail-safe unit 96b, an abnormal state of the electric actuator 61 is detected, and the fail-safe operation FS disables the electric actuator 61 from being driven again. If the determination in step S30 is positive, in step S50 corresponding to the function of the abnormality detection stop unit 96d, the switching control of the shift position POSsh by the electric actuator 61 is stopped, and the abnormality of the electric actuator 61 is masked. Next, in S60, which corresponds to the function of the power supply control unit 96c, it is determined whether or not there is a power failure in the first power supply 70. If the determination in S60 is negative, the process returns to S20. If the determination in S60 is positive, the power supply to the electric actuator 61 is switched to the second power supply 72 in S70, which corresponds to the function of the power supply control unit 96c. Next, in S80, which corresponds to the function of the shift control unit 96a, a target position for setting the shift position POSsh to the P position is reset. Next, in S90, which corresponds to the function of the shift control unit 96a, the electric actuator 61 is re-driven to switch to the P position. If the determination in S20 is positive, or following S90, in S100, which corresponds to the function of the shift control unit 96a, when the position signal Sposop reaches the target position, the switching control by the electric actuator 61 is completed.

[0066] FIG. 4 is a diagram showing an example of a time chart when the control operation shown in the flowchart of FIG. 3 is executed. In FIG. 4, time t1 indicates the time when output of a P lock command is initiated. Time t2 indicates the time when drive of the electric actuator 61 is initiated to switch the shift position POSsh from the non-P position to the P position. Time t3 indicates the time when it is determined that a power failure state of the first power source 70 has occurred because the first power source voltage Vbat1 has dropped below a predetermined voltage Vbatf. If the power failure state continues for a power failure determination time TM1ps or longer, a power failure of the first power source 70 is determined (see time t5), and the power supply to the electric actuator 61 is switched to the second power source 72 (see time t6). In the comparative example shown by the dashed line, an abnormal state of the electric actuator 61 is detected and the fail-safe operation FS is performed before the power supply to the electric actuator 61 is switched to the second power source 72. Therefore, even after the power supply is switched to the second power supply 72, the fail-safe operation FS prevents the electric actuator 61 from being re-driven (see time t6 and onward). In contrast, in this embodiment shown by the solid line, a temporary power failure of the first power supply 70 is determined because the power supply failure state continues for more than the temporary power supply failure determination time TMlpsp before an abnormal state of the electric actuator 61 is detected (see time t4 to time t5). Then, from the time the temporary power supply failure is determined until the power supply is switched to the second power supply 72, the abnormality of the electric actuator 61 is masked (see the shaded portion from time t4 to time t6 in the ACT abnormal state). As a result, the fail-safe operation FS is not performed, and after the power supply is switched to the second power supply 72, the electric actuator 61 is re-driven and switched to the P position (see time t6 to time t7). Furthermore, if a fail-safe operation FS is performed due to a power failure occurring when the first power source 70 is being used to supply power, the use of the first power source 70 is stopped when a temporary power failure is determined (see times t4 to t6).

[0067] As described above, according to this embodiment, when a power failure occurs during a transition from the non-P position to the P position, the abnormal state of the electric actuator 61 is not detected until the power supply to the electric actuator 61 is switched to the second power supply 72. As a result, the fail-safe operation FS is not performed when the power supply to the electric actuator 61 is switched to the second power supply 72, and therefore, it is possible to restart the electric actuator 61. Therefore, when a power failure occurs during a transition from the non-P position to the P position, it is possible to switch to the P position.

[0068] Furthermore, according to this embodiment, a temporary power failure of the first power source 70 is determined when the occurrence of a power failure state continues for at least a temporary power source failure determination time TMlpsp, which is set in advance to a value shorter than the predetermined time TMf used to detect an abnormal state of the electric actuator 61. Furthermore, the abnormal state of the electric actuator 61 is not detected from the time when the temporary power source failure is determined until the power supply to the electric actuator 61 is switched to the second power source 72. As a result, the temporary power source failure of the first power source 70 is determined at a timing earlier than the detection of the abnormal state of the electric actuator 61, and therefore the fail-safe operation FS is not reliably performed when the power supply to the electric actuator 61 is switched to the second power source 72.

[0069] Furthermore, according to this embodiment, the predetermined voltage Vbatf for determining the occurrence of a power failure state of the first power source 70 is set in advance to a higher value when determining a temporary power failure than when determining a power failure. This allows a temporary power failure of the first power source 70 to be determined at an earlier timing than when an abnormal state of the electric actuator 61 is detected, thereby widening the range over which an abnormal state of the electric actuator 61 cannot be detected.

[0070] Furthermore, according to this embodiment, if a power failure occurs during a transition from the non-P position to the P position, use of the first power source 70 is stopped until the power supply to the electric actuator 61 is switched to the second power source 72. As a result, the fail-safe operation FS caused by the occurrence of a power failure when the first power source 70 is being used to supply power to the electric actuator 61 is not performed.

[0071] Furthermore, according to this embodiment, if a power failure occurs during a transition from the non-P position to the P position and the power supply to the electric actuator 61 is switched to the second power supply 72, the electric actuator 61 is driven again to switch to the P position. As a result, after the power supply to the electric actuator 61 is switched to the second power supply 72, the electric actuator 61 is switched to the P position.

[0072] Furthermore, according to this embodiment, when the electric actuator 61 is driven again, the drive amount to the P position is calculated using the position signal Sposop at the time of stagnation and the change in the position signal Sposop during the free state. As a result, after the power supply to the electric actuator 61 is switched to the second power source 72, the electric actuator 61 can be appropriately driven to switch to the P position.

[0073] Although the embodiments of the present invention have been described in detail above with reference to the drawings, the present invention can also be applied to other embodiments.

[0074] For example, in the above-described embodiment, if the vehicle 10 does not have the function of performing fail-safe operation FS due to a power failure occurring when the first power source 70 is used for power supply, it is not necessarily necessary to stop the switching control at S50 in the flowchart of FIG. 3.

[0075] Furthermore, in the above-described embodiment, the SBW device 60 switches the shift position POSsh of the automatic transmission 18 between the P position and a non-P position, but this is not limiting. For example, the SBW device 60 may be a switching device that switches the operating position of the electric actuator 61 to positions that respectively correspond to the P, R, N, D positions, etc. of the automatic transmission 18. In this case, the operating positions of the electric actuator 61 that respectively correspond to the R, N, D positions, etc. other than the P position of the automatic transmission 18 are set as the operating positions of the electric actuator 61 that correspond to the non-P position of the automatic transmission 18.

[0076] In the above-described embodiment, the power transmission device 16 includes the automatic transmission 18 and transmits the power of the engine 12 to the drive wheels 14. However, this is not a limitation. For example, the power transmission device may not include an automatic transmission. That is, the vehicle 10 may be a vehicle that does not include the automatic transmission 18, such as a series hybrid vehicle that does not include an automatic transmission. Alternatively, the vehicle 10 may be an electric vehicle that does not include the automatic transmission 18 and is capable of running on a motor by driving a drive motor with battery power. In a power transmission device that does not include an automatic transmission, the shift position is changed by a switching device, for example, similar to the automatic transmission 18. In a power transmission device that does not include an automatic transmission, power is transmitted through a power transmission path formed by a mechanical mechanism such as a gear mechanism, and the neutral state is changed by disengaging a clutch provided in the power transmission path. In short, the present invention can be applied to any vehicle that is equipped with a switching device that switches the shift position of a power transmission device that transmits power from a power source to the drive wheels by operating an electric actuator, a first power source that supplies power to drive the electric actuator, and a second power source that supplies power to drive the electric actuator when a power failure occurs in the first power source.

[0077] It should be noted that the above is merely one embodiment, and the present invention can be embodied in various forms with various modifications and improvements based on the knowledge of those skilled in the art. [Explanation of symbols]

[0078] 10: Vehicle 12: Engine (power source) 14: Drive wheels 16: Power transmission device 20: Output shaft (rotating member) 60: Shift-by-wire device (switching device) 61: Electric actuator 70: First power source 72: Second power source 90: Electronic control device (control device) 96a: Shift control unit 96b: Fail-safe unit 96c: Power supply control unit 96d: Abnormality detection and stopping unit

Claims

1. A control device for a vehicle including: a switching device that switches a shift position of a power transmission device that transmits power from a power source to drive wheels by operation of an electric actuator; a first power source that supplies power to drive the electric actuator; and a second power source that supplies power to drive the electric actuator during a power failure state in which power to drive the electric actuator is not supplied from the first power source, a shift control unit that controls switching of the shift position between a parking position in which a rotating member that rotates together with the drive wheels is mechanically fixed so as not to rotate, and a non-parking position other than the parking position; a fail-safe unit that performs a fail-safe operation to disable restarting of the electric actuator when an abnormal state of the electric actuator is detected because drive of the electric actuator has stagnated for a predetermined period of time or more during transition of switching between the parking position and the non-parking position; a power supply control unit that switches power supply to the electric actuator to the second power supply when a power failure of the first power supply is determined during the occurrence of the power failure state; an abnormality detection stopping unit that, when the power supply failure state occurs during a transition of switching from the non-parking position to the parking position, does not allow the fail-safe unit to detect an abnormal state of the electric actuator until the power supply control unit switches the power supply to the electric actuator to the second power supply; A vehicle control device comprising:

2. the power supply control unit determines the occurrence of the power supply failure state when the voltage of the first power supply becomes equal to or lower than a predetermined voltage, determines the power supply failure when the occurrence of the power supply failure state continues for a predetermined power supply failure determination time or more that is a value longer than the predetermined time, and determines a temporary power supply failure of the first power supply when the occurrence of the power supply failure state continues for a predetermined temporary power supply failure determination time or more that is a value shorter than the predetermined time, 2. The vehicle control device according to claim 1, wherein the abnormality detection stopping unit does not cause the fail-safe unit to detect an abnormal state of the electric actuator from the time the power supply control unit determines that the temporary power supply has failed until the power supply failure is determined and the power supply to the electric actuator is switched to the second power supply.

3. 3. The vehicle control device according to claim 2, wherein the predetermined voltage is set to a value higher when determining whether the temporary power supply has failed than when determining whether the power supply has failed.

4. the fail-safe unit performs the fail-safe operation when the power supply failure state occurs while the first power supply is being used by the power supply control unit to supply power to the electric actuator, 2. The vehicle control device according to claim 1, wherein, when the power supply failure state occurs during a transition from the non-parking position to the parking position, the abnormality detection stop unit causes the power supply control unit to stop using the first power supply until the power supply to the electric actuator is switched to the second power supply.

5. 5. The vehicle control device according to claim 1, wherein when the power supply control unit switches the power supply to the electric actuator to the second power supply while the power supply failure state occurs during a transition from the non-parking position to the parking position, the shift control unit re-drives the electric actuator to switch to the parking position.

6. 6. The vehicle control device according to claim 5, wherein, when restarting the electric actuator, the shift control unit calculates a driving amount to the parking position using driving information of the electric actuator at the time when driving of the electric actuator stagnated due to the occurrence of the power supply failure state and operation information of the electric actuator during a transient period when driving of the electric actuator stagnated.

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