Vehicle control system

Abstract

The present invention provides a vehicle control device that can reduce the shock associated with switching to a non-parking position, even when the torque output response of the power source is slow. [Solution] Based on one of the predetermined operations performed when requesting a switch from the parking position to the non-parking position, the power source is output with torque in such a way that the load on the parking lock mechanism is reduced. As a result, the power source is output with torque even before the operation of the parking lock mechanism to switch to the non-parking position begins. Therefore, sufficient torque from the power source can be output to reduce the shock before the shock associated with switching to the non-parking position by the parking lock mechanism occurs. Thus, even when the torque output response of the power source is slow, the shock associated with switching to the non-parking position can be reduced.

Description

Technical Field

[0001] The present invention relates to a control device for a vehicle having a parking lock mechanism that is operated to switch a shift position based on an operation by a driver.

Background Art

[0002] A vehicle including a power source, a power transmission device that transmits the power of the power source to drive wheels, a shift operation device that is operated by a driver to an operation position corresponding to a shift position of the power transmission device, and a parking lock mechanism that is operated to switch the shift position to either a parking position in which rotation of a rotating member that rotates together with the drive wheels is mechanically blocked or a non-parking position in which rotation of the rotating member is permitted based on an operation of the shift operation device by the driver, and a control device thereof are well known. For example, a control device for a vehicle described in Patent Document 1 is such a device. Patent Document 1 discloses that when a target shift position is switched to a non-parking position, the parking lock mechanism is operated to switch to the non-parking position, and the torque of the power source is output so that the load applied to the parking lock mechanism is reduced.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] By the way, in the technology described in Patent Document 1, when the operation of the parking lock mechanism that switches to the non-parking position is started, the power source starts outputting torque in such a way that the load on the parking lock mechanism is reduced. Therefore, if the torque output response of the power source is slow, there is a possibility that the vehicle will switch to the non-parking position before sufficient torque from the power source is output to reduce the shock associated with the switching to the non-parking position by the parking lock mechanism. In that case, the desired shock reduction effect may not be obtained when the vehicle switches to the non-parking position.

[0005] The present invention was made against the above circumstances, and its objective is to provide a vehicle control device that can reduce the shock associated with switching to a non-parking position, even when the torque output response of the power source is slow. [Means for solving the problem]

[0006] The gist of the first invention is a control device for a vehicle comprising: (a) a power source; a power transmission device for transmitting power from the power source to the drive wheels; a shift operating device operated by a driver to an operating position corresponding to the shift position of the power transmission device; and a parking lock mechanism which is operated to switch the shift position to either a parking position in which the rotation of a rotating member that rotates with the drive wheels is mechanically prevented, or a non-parking position in which the rotation of the rotating member is permitted, based on the driver's operation of the shift operating device, wherein (b) the power source outputs torque such that the load on the parking lock mechanism is reduced based on one of a plurality of predetermined operations performed by the driver when requesting a switch of the shift position from the parking position to the non-parking position. [Effects of the Invention]

[0007] According to the first invention, based on one of the predetermined operations performed when requesting a switch from the parking position to the non-parking position, the torque of the power source is output in such a way that the load on the parking lock mechanism is reduced. As a result, the torque of the power source is output before the operation of the parking lock mechanism to switch to the non-parking position begins. Therefore, sufficient torque from the power source to reduce the shock can be output before the shock associated with switching to the non-parking position by the parking lock mechanism occurs. Thus, even when the torque output response of the power source is slow, the shock associated with switching to the non-parking position can be reduced. [Brief explanation of the drawing]

[0008] [Figure 1] This diagram illustrates the schematic configuration of a vehicle to which the present invention is applied, as well as the main components of the control functions for various types of control in the vehicle. [Figure 2] This flowchart explains the key aspects of the control operation of an electronic control unit, specifically the control operation to reduce the shock associated with switching to a non-P range, even when the output response of the motor torque is slow. [Figure 3] This figure shows an example of a time chart when the control operation shown in the flowchart in Figure 2 is performed. [Figure 4] This figure illustrates the schematic configuration of a vehicle other than the one shown in Figure 1 to which the present invention is applied, and also illustrates the main parts of the control functions for various control functions in the vehicle. [Figure 5] This figure shows an example of a time chart when the control operation shown in the flowchart of Figure 2 is performed in Example 2. [Modes for carrying out the invention]

[0009] Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. [Examples]

[0010] Figure 1 is a diagram illustrating the schematic configuration of a vehicle 10 to which the present invention is applied, and also illustrates the main parts of the control functions for various controls in the vehicle 10. In Figure 1, the vehicle 10 includes an electric motor 12 that functions as a power source, left and right drive wheels 14, and a power transmission device 16 that transmits power from the electric motor 12 to the drive wheels 14. The above "left and right" refers to left and right with respect to the forward direction of the vehicle 10.

[0011] The electric motor 12 is a known rotating electric machine, a so-called motor generator. The electric motor 12 is connected to a battery 62 provided in the vehicle 10 via an inverter 60 provided in the vehicle 10. The motor torque Tm, which is the torque of the electric motor 12 as a power source torque, is controlled by the inverter 60 controlled by an electronic control device 80, which will be described later.

[0012] The power transmission device 16 includes a reduction gear mechanism 18, an output gear 20, a differential gear 22, left and right drive shafts 24, etc. The reduction gear mechanism 18 is a gear pair having an input gear 18i and an output gear 18o that meshes with the input gear 18i. The input gear 18i is connected to the electric motor 12, and the output gear 18o is connected to the output gear 20. The output gear 20 meshes with the ring gear 22r of the differential gear 22. The drive shafts 24 connect the differential gear 22 to the drive wheels 14.

[0013] Vehicle 10 is further equipped with a shift operating device 30, a switching device 40, and the like. In vehicle 10, the shift range RNGsh of the power transmission device 16 is switched using a shift-by-wire (SBW) system. The shift range RNGsh is synonymous with the shift position. In other words, the range in the shift range is synonymous with the position.

[0014] The shift operation device 30 is an operating device for manually selecting from multiple types of shift ranges RNGsh in the power transmission device 16. In other words, the shift operation device 30 is an operating device that receives a request to switch the shift range RNGsh of the power transmission device 16 when manually operated. The shift operation device 30 is operated by the driver to the operating position POSop corresponding to the shift range RNGsh of the power transmission device 16. The operating position POSop includes, for example, P (parking), R (reverse), N (neutral), and D (forward) operating positions. The shift range RNGsh includes, for example, the P, R, N, and D ranges. The power transmission device 16 switches the shift range RNGsh by electrical control based on the operating position POSop.

[0015] The P operating position is the POSop operating position for selecting the P range of the power transmission device 16. The P range of the power transmission device 16 is the RNGsh shift range in which the power transmission device 16 is in a neutral state and the rotation of the output gear 20, which is a rotating member that rotates together with the drive wheels 14, is mechanically prevented. The neutral state of the power transmission device 16 is a state in which power transmission in the power transmission device 16 is cut off, that is, a state in which the power transmission device 16 is unable to transmit power. The state in which the rotation of the output gear 20 is mechanically prevented is a state in which the output gear 20 is mechanically fixed so that it cannot rotate, and is the P lock state of the power transmission device 16. The output gear 20 is mechanically fixed so that it cannot rotate by the switching device 40. The state in which the rotation of the output gear 20 is mechanically prevented is synonymous with the state in which the rotation of the parking lock gear 52, which will be described later, is mechanically prevented.

[0016] The R operation position is the operation position POSop for selecting the R range of the power transmission device 16. The R range of the power transmission device 16 is the shift range RNGsh that enables the vehicle 10 to reverse. The N operation position is the operation position POSop for selecting the N range of the power transmission device 16. The N range of the power transmission device 16 is the shift range RNGsh in which the power transmission device 16 is in a neutral state. The D operation position is the operation position POSop for selecting the D range of the power transmission device 16. The D range of the power transmission device 16 is the shift range RNGsh that enables the vehicle 10 to move forward.

[0017] The R, N, and D ranges of the power transmission device 16 are all shift ranges RNGsh in which the rotation of the output gear 20 is permitted, and are non-P ranges of the power transmission device 16. The R, N, and D operation positions are all non-P operation positions for selecting the non-P ranges of the power transmission device 16. The state in which the rotation of the output gear 20 is permitted is a state in which the mechanical fixation of the output gear 20 is released, that is, a state in which the P-lock state of the power transmission device 16 is released, and is a non-P-lock state of the power transmission device 16.

[0018] The shift operation device 30 has a shift lever 32 and a P switch 34 that are selectively operated by the driver to a plurality of operation positions POSop respectively corresponding to a plurality of shift ranges RNGsh of the power transmission device 16. Both the shift lever 32 and the P switch 34 are self-returning or 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. The shift operation device 30 includes the home position that is returned when not being operated by the driver as an operation position POSop. The shift operation device 30 has a plurality of positions where the operator is operated with respect to the home position as the operation position POSop. The operation position POSop of the shift lever 32 is the lever position Plev, and the operation position POSop of the P switch 34 is the P switch on position Ppon.

[0019] The shift lever 32 is selectively operated by the driver to the corresponding lever position Plev in order to set the shift range RNGsh to the desired shift range RNGsh among the non-P ranges. The P switch 34 is operated by the driver to set the shift range RNGsh to the P range. The lever position Plev includes, for example, the R, N, D, and H operating positions. The H operating position is the home position of the shift lever 32.

[0020] The shift operation device 30 is equipped with a lever position sensor 36 that outputs a lever position signal Splev corresponding to the lever position Plev to an electronic control device 80, which will be described later. The P switch 34 is, for example, a push-button switch, and each time it is pressed by the driver to the P switch ON position Ppon, which is the P operation position, it outputs a P switch signal Sppon to the electronic control device 80, which will be described later. The position when the P switch 34 is not pressed is the home position of the P switch 34. The lever position signal Splev and the P switch signal Sppon are operation position signals Sposop corresponding to the operation position POSop.

[0021] The switching device 40 includes an electric actuator 42, an encoder 44, a parking lock mechanism 50, etc. The electric actuator 42 is an actuator that operates the parking lock mechanism 50. The encoder 44 is a sensor that counts the operating amount of the electric actuator 42. The parking lock mechanism 50 includes a parking lock gear 52, a parking lock pole 54, a cam 56, a parking rod 58, etc. The parking lock gear 52 is a member provided on the power transmission device 16 so as to rotate integrally with the output gear 20, and is a rotating member that rotates together with the drive wheel 14. The parking lock pole 54 has a claw portion that meshes with the gear teeth of the parking lock gear 52, and is a member that can mesh with the parking lock gear 52. The cam 56 is provided at the tip of the parking rod 58 on the side of the parking lock pole 54. The cam 56 is a tapered member that meshes the parking lock pole 54 with the parking lock gear 52. The parking rod 58 is a member that supports the cam 56 at one end, and is mechanically connected to the electric actuator 42 via a member not shown on the other end side.

[0022] The electric actuator 42 is driven based on a P-switching control command signal Splock from an electronic control device 80 described later. The switching device 40 operates the parking lock mechanism 50 by driving the electric actuator 42, and switches the shift range RNGsh of the power transmission device 16 between the P range and the non-P range. The parking lock mechanism 50 is operated to switch the shift range RNGsh to either the P range or the non-P range based on the operation of the shift operation device 30 by the driver. In the vehicle 10, the SBW system is adopted, and the parking lock mechanism 50 is operated to switch the shift range RNGsh based on the P-switching control command signal Splock, which is a control command signal corresponding to the operation of the shift operation device 30 by the driver.

[0023] Vehicle 10 is further equipped with an electronic control unit 80, which acts as a controller for vehicle 10, including control devices related to the control of the electric motor 12. The electronic control unit 80 is composed of a so-called microcomputer, for example, which includes a CPU, RAM, ROM, input / output interface, etc. The CPU performs various controls on vehicle 10 by performing signal processing according to a program pre-stored in ROM while utilizing the temporary storage function of RAM.

[0024] The electronic control unit 80 is supplied with various signals based on detection values ​​from various sensors installed in the vehicle 10. Examples of these sensors include the P switch 34, lever position sensor 36, encoder 44, vehicle speed sensor 70, accelerator opening sensor 72, brake sensor 74, and acceleration sensor 76. Examples of these signals include the P switch signal Spon, lever position signal Splev, pulse signal Senc, vehicle speed V, accelerator opening θacc, brake operation amount Bra, and longitudinal acceleration G.

[0025] The electronic control unit 80 outputs various command signals to each device installed in the vehicle 10. These devices include, for example, the electric actuator 42 and the inverter 60. The various control command signals include, for example, the P switching control command signal Splock for controlling the switching of the shift range RNGsh (P range, non-P range), and the motor control command signal Sm for controlling the electric motor 12.

[0026] The electronic control unit 80 includes an electric motor control unit 82 and a shift control unit 84 in order to implement various controls in the vehicle 10.

[0027] The motor control unit 82 calculates the amount of drive requested by the driver to the vehicle 10 by applying the accelerator opening θacc and vehicle speed V to a predetermined drive request map, for example. This drive request is, for example, the requested drive torque at the drive wheels 14. The motor control unit 82 outputs a motor control command signal Sm to the inverter 60 to control the motor 12 so that a motor torque Tm that realizes the drive request is obtained, taking into account transmission losses, auxiliary loads, etc.

[0028] The shift control unit 84 switches the shift range RNGsh of the power transmission unit 16 based on the operating position POSop in the shift operating device 30. For example, the shift control unit 84 sets a requested range, which is the shift range RNGsh desired by the driver, based on the lever position signal Splev or the P switch signal Spon. The shift control unit 84 then switches to the shift range RNGsh corresponding to the requested range.

[0029] When the shift control unit 84 sets a requested range corresponding to the operating position POSop, it determines whether the same operating position signal Sposop has been output continuously for a shift operation determination time TMshf or longer. If the shift control unit 84 determines that the same operating position signal Sposop has been output continuously for a shift operation determination time TMshf or longer, it determines that the operating position POSop is the operating position POSop corresponding to that operating position signal Sposop. The shift control unit 84 sets a requested range corresponding to the operating position POSop, and sets the shift range RNGsh of the power transmission device 16 to the shift range RNGsh corresponding to the requested range. The shift operation determination time TMshf is a threshold for determining, for example, that a shift operation has been performed by the driver, and is a predetermined threshold for determining that the same operating position POSop has been reliably operated by the driver's intention. The shift operation determination time TMshf is a predetermined holding time for which it can be determined that the operation was intended by the driver. For example, different values ​​are set for each operating position POSop according to the vehicle state.

[0030] When the shift control unit 84 detects the input of the P switch signal Spon while the shift range RNGsh is in a non-P range, it sets the P range as the requested range. The shift control unit 84 outputs a P switching control command signal Splock to the electric actuator 42 to engage the parking lock pawl 54 with the parking lock gear 52 in order to switch the shift range RNGsh to the P range.

[0031] When the shift control unit 84 detects the input of the lever position signal Splev while the shift range RNGsh is in the P range, it sets the non-P range corresponding to the lever position signal Splev as the requested range. The shift control unit 84 outputs a P switching control command signal Splock to the electric actuator 42 to release the engagement of the parking lock pawl 54 with the parking lock gear 52 so as to switch the shift range RNGsh to the non-P range. In addition, the shift control unit 84 switches to the shift range RNGsh, which corresponds to the requested range, among the non-P ranges. In other words, the shift control unit 84 starts switching to the non-P range in the parking lock mechanism 50 after the shift operation determination time TMshf has elapsed since the shift control unit 84 was operated to the non-P position and the non-P position has been continuously held. The state in which the engagement between the parking lock pawl 54 and the parking lock gear 52 has been released is called the P unlock state.

[0032] Here, when the shift range RNGsh is in the P range and the vehicle is parked on an incline, a load is applied to the engagement points of the parking lock pole 54 and the parking lock gear 52. Torsional torque is accumulated in the components (such as the drive shaft 24) in the power transmission path between the drive wheels 14 and their engagement points. When switching from the P range to a non-P range, this torsional torque is released, which may cause a shock.

[0033] When the shift range RNGsh is switched from the P range to the non-P range, the motor control unit 82 outputs a motor torque Tm in a direction that reduces the load on the parking lock mechanism 50, that is, in a direction that counteracts the torsional torque. On uphill roads, the motor control unit 82 outputs a motor torque Tm that is a forward torque, i.e., a positive torque, while on downhill roads, it outputs a motor torque Tm that is a reverse torque, i.e., a negative torque. For example, the greater the gradient of the uphill or downhill road, the greater the absolute value of the motor torque Tm, i.e., the shock reduction torque. On flat roads, for example, the shock reduction torque is set to zero. The gradient of the uphill or downhill road is calculated based on, for example, the longitudinal acceleration G.

[0034] Incidentally, if the output response of the motor torque Tm is slow, even if the output of the motor torque Tm is started at the time of switching the parking lock mechanism 50 to a non-P range, for example, there is a risk that it will not be possible to output enough motor torque Tm to reduce the shock before the shock occurs. Therefore, if the output response of the motor torque Tm is slow, when the parking lock gear 52 is set to the P unlock state, there is a risk that sufficient motor torque Tm cannot be applied to counteract the torsional torque, and a sufficient shock reduction effect cannot be obtained.

[0035] Therefore, the motor control unit 82 outputs a motor torque Tm based on one of the non-P switching request operations OPnp so as to reduce the load on the parking lock mechanism 50. The non-P switching request operations OPnp are a set of predetermined operations performed by the driver when requesting a switch of the shift range RNGsh from the P range to the non-P range.

[0036] The non-P switching request operation OPnp includes, for example, an operation to select a non-P operating position corresponding to the non-P range in the shift operating device 30, and a brake operation to activate the wheel brake. The operation in which the driver selects a non-P operating position is an operation in which the driver moves the shift lever 32 to a lever position Plev other than the H operating position, and is detected by the lever position sensor 36. The brake operation in which the driver activates the wheel brake is an operation performed by the driver prior to operating the shift operating device 30 to enable switching to the non-P range, and is detected by the brake sensor 74.

[0037] If the motor control unit 82 determines that there is a non-P switching request operation OPnp, it outputs a motor torque Tm to reduce the load on the parking lock mechanism 50.

[0038] If the operation to select a non-P operating position is not continued for a shift operation judgment time TMshf or longer, the switching to a non-P range in the parking lock mechanism 50 will not begin. If the output of the motor torque Tm is started at the time the operation to select a non-P operating position is performed, it is possible to output a sufficient motor torque Tm to reduce shock. For this reason, any one of the non-P switching request operations OPnp only needs to be an operation to select a non-P operating position.

[0039] Figure 2 is a flowchart illustrating the main part of the control operation of the electronic control device 80. It is a flowchart illustrating the control operation to reduce the shock associated with switching to a non-P range, even when the output response of the motor torque Tm is slow, and is, for example, executed repeatedly.

[0040] In Figure 2, each step in the flowchart corresponds to a function of the motor control unit 82. In step S10 (the steps will be omitted hereafter), it is determined whether or not there was a driver request operation OPnp to switch to a non-P position. If the determination in S10 is negative, this routine is terminated. If the determination in S10 is positive, in S20, the motor torque Tm is output to reduce the load on the parking lock mechanism 50. Next, in S30, it is determined whether or not the switching device 40 has been switched to the non-P range position in which the shift range RNGsh is held in the non-P range. If the determination in S30 is negative, the process returns to S20. If the determination in S30 is positive, in S40, the output of the motor torque Tm is stopped.

[0041] Figure 3 shows an example of a time chart when the control operation shown in the flowchart of Figure 2 is performed. In Figure 3, time t1a indicates the moment when the driver applies the brakes. Time t2a indicates the moment when the driver moves the shift lever 32 to the D position. This operation of the shift lever 32 starts the output of an electric motor torque Tm to reduce the load on the parking lock mechanism 50. When the operation of the shift lever 32 to the D position is held continuously for the shift operation judgment time TMshf, the operation of the electric actuator 42 to switch the shift range RNGsh from the P range to the non-P range is started (see time t3a). During the switching from the P range to the non-P range by the operation of the electric actuator 42, the parking lock gear 52 is set to the P unlock state (see time t4a). At the time the P unlock state is set, sufficient electric motor torque Tm is output to counteract the torsional torque, so shock reduction is possible. After the switching device 40 is switched to the non-P range position, the output of the motor torque Tm is stopped. At the time t1a when the driver applies the brakes, the output of the motor torque Tm may be started to reduce the load on the parking lock mechanism 50.

[0042] As described above, according to this embodiment, based on any one of the non-P switching request operations OPnp, the motor torque Tm is output in such a way that the load on the parking lock mechanism 50 is reduced. As a result, the motor torque Tm is output before the operation of the parking lock mechanism 50 to switch to the non-P range begins. Therefore, sufficient motor torque Tm can be output to reduce the shock before the shock associated with switching to the non-P range by the parking lock mechanism 50 occurs. Thus, even when the output response of the motor torque Tm is slow, the shock associated with switching to the non-P range can be reduced.

[0043] Furthermore, according to this embodiment, the non-P switching request operation OPnp includes an operation to select a non-P operating position in the shift operation device 30, and a brake operation to activate the wheel brake. As a result, the motor torque Tm is output appropriately even before the operation of the parking lock mechanism 50 that switches to the non-P range is initiated.

[0044] Furthermore, according to this embodiment, one of the non-P switching request operations OPnp is an operation to select a non-P operating position. This ensures that when there is a high probability of switching to the non-P range, the motor torque Tm is output appropriately even before the operation of the parking lock mechanism 50 that switches to the non-P range begins.

[0045] Next, other embodiments of the present invention will be described. In the following description, parts common to multiple embodiments will be denoted by the same reference numerals and their descriptions will be omitted. [Examples]

[0046] Figure 4 is a diagram illustrating the schematic configuration of a vehicle 100 to which the present invention is applied, as well as a diagram illustrating the main parts of the control functions for various controls in the vehicle 100. Vehicle 100 is a different vehicle from vehicle 10 in the aforementioned Embodiment 1. Vehicle 100 differs from vehicle 10 mainly in that the shift operating device 30 and switching device 40 used in the SBW system are replaced with a shift operating device 110 and switching device 120 used in the Mechalink system. The differences from vehicle 10 will be explained in detail below.

[0047] The shift operation device 110 is an operating device for manually selecting from multiple types of shift ranges RNGsh in the power transmission device 16. The shift operation device 110 has a shift lever 112 that can be selectively operated by the driver to multiple operating positions POSop, each corresponding to one of the multiple shift ranges RNGsh of the power transmission device 16. The operating positions POSop of the shift lever 112 include, for example, P, R, N, and D operating positions. The operating positions POSop of the shift lever 112 are arranged in the order of P, R, N, and D operating positions, each held with a certain degree of control, and operable to adjacent operating positions POSop.

[0048] The shift operation device 110 further includes a shift preparation switch 114, an operation sensor 116, and an operation position sensor 118. The shift preparation switch 114 is a push-button switch that allows operation from the P operation position to the R operation position. In the shift operation device 110, operation from the P operation position to the R operation position is restricted, and this restriction is released by pushing the shift preparation switch 114. In other words, operation from the P operation position to the R operation position is possible when the shift preparation switch 114 is pushed. The operation sensor 116 is a sensor that detects when the shift preparation switch 114 is pushed and outputs a push operation signal Snpon to the electronic control unit 130, which will be described later. The operation position sensor 118 is a sensor that outputs an operation position signal Sposop corresponding to the operation position POSop to the electronic control unit 130, which will be described later.

[0049] The switching device 120 includes a connecting member 122, a parking lock mechanism 50, and the like. The parking lock mechanism 50 is mechanically connected to the shift operating device 110 (particularly the shift lever 112) via the connecting member 122, which includes links and cables. The parking lock mechanism 50 is mechanically connected to the shift operating device 110 and is operated in conjunction with the driver's operation of the shift operating device 110 to switch the shift range RNGsh between the P range and the non-P range.

[0050] The vehicle 100 is further equipped with an electronic control unit 130, which serves as a controller for the vehicle 100, including control devices related to the control of the electric motor 12. The electronic control unit 130 has the same configuration as the electronic control unit 80 in the above-described embodiment 1.

[0051] The electronic control unit 130 is supplied with various signals based on detection values ​​from various sensors installed in the vehicle 100. Examples of these sensors include a vehicle speed sensor 70, an accelerator pedal position sensor 72, a brake sensor 74, an acceleration sensor 76, an operation sensor 116, and an operation position sensor 118. Examples of these signals include vehicle speed V, accelerator pedal position θacc, brake operation amount Bra, longitudinal acceleration G, push operation signal Snpon, and operation position signal Sposop.

[0052] The electronic control device 130 outputs various command signals (for example, motor control command signal Sm) to each device (for example, inverter 60) installed in the vehicle 100.

[0053] The non-P switching request operation OPnp includes, for example, an operation to select a non-P operating position corresponding to the non-P range in the shift operating device 110, and a brake operation to activate the wheel brake. The operation in which the driver selects a non-P operating position is, for example, an operation in which the driver moves the shift lever 112 from the P operating position to the R operating position, and is detected by the operating position sensor 118. The brake operation in which the driver activates the wheel brake is an operation performed prior to the driver pressing the shift preparation switch 114 to enable operation from the P operating position to the R operating position, and is detected by the brake sensor 74.

[0054] The non-P switching request operation OPnp further includes the driver pressing the shift preparation switch 114. The driver pressing the shift preparation switch 114 is a preparatory operation that enables the shift operating device 110 to operate to a non-P operating position when the shift range RNGsh is in the P range, and is detected by the operating sensor 116.

[0055] If the brakes are not applied, the shift preparation switch 114 cannot be pressed. If the output of the motor torque Tm starts when the brakes are applied, it is possible to output a sufficient motor torque Tm to reduce the shock. Therefore, any one of the non-P switching request operations OPnp only needs to be a brake operation.

[0056] In this embodiment, which employs a mechanical linkage system, the control operations shown in the flowchart of Figure 2 in the aforementioned Embodiment 1 can be performed.

[0057] Figure 5 shows an example of a time chart when the control operation shown in the flowchart of Figure 2 is performed in this embodiment. In Figure 5, time t1b indicates the time when the driver applies the brakes. Along with this brake operation, the output of the motor torque Tm is started to reduce the load on the parking lock mechanism 50. With the brakes applied, the shift preparation switch 114 is pressed, and the shift lever 112 is operated from the P position to the R position. During the operation from the P position to the R position, the parking lock gear 52 is set to the P unlock state (see time t2b). At the time the P unlock state is set, sufficient motor torque Tm is output to counteract the torsional torque, so shock reduction is possible. After the shift lever 112 is operated to the R position, the output of the motor torque Tm is stopped.

[0058] As described above, according to this embodiment, similar to Embodiment 1 described above, the shock associated with switching to a non-P range can be reduced even when the output response of the motor torque Tm is slow.

[0059] Furthermore, according to this embodiment, the non-P switching request operation OPnp includes an operation to select a non-P operating position in the shift operating device 110, a brake operation to activate the wheel brake, and a preparatory operation to enable operation to the non-P operating position. As a result, the motor torque Tm is output appropriately even before the operation of the parking lock mechanism 50 that switches to the non-P range is initiated.

[0060] Furthermore, according to this embodiment, one of the non-P switching request operations OPnp is a brake operation. This ensures that the motor torque Tm is output appropriately before the operation of the parking lock mechanism 50, which switches to the non-P range, begins when there is a high probability of switching to the non-P range.

[0061] Although embodiments of the present invention have been described in detail above with reference to the drawings, the present invention is also applicable to other embodiments.

[0062] For example, in the embodiment described above, the power source may be an engine in addition to, or instead of, the electric motor 12. In this case, the torque of the power source used to reduce the load on the parking lock mechanism 50 is the torque of the engine in addition to, or instead of the torque Tm of the electric motor.

[0063] Furthermore, in the aforementioned embodiment 2, the shift operation device 110 may be a so-called gate-type operation device in which the restriction on operation from the P operation position to the R operation position is released by brake operation.

[0064] Furthermore, in the above-described embodiment 1, the non-P switching request operation OPnp may further include preparatory operations that enable the shift operating device 30 to operate to a non-P operating position when the shift range RNGsh is in the P range.

[0065] It should be noted that the above-described embodiment is merely one possible design, and the present invention can be implemented in various modified and improved forms based on the knowledge of those skilled in the art. [Explanation of symbols]

[0066] 10: Vehicle 12: Electric motor (power source) 14: Drive wheels 16: Power transmission device 20: Output gear (rotating component that rotates with the drive wheels) 30: Shift operation device 32: Shift lever (operator) 34: P switch (operator) 50: Parking lock mechanism 52: Parking lock gear (rotating component that rotates with the drive wheels) 80: Electronic control unit (control unit) 100: Vehicle 110: Shift operation device 130: Electronic control unit (control unit)

Claims

1. A control device for a vehicle comprising: a power source; a power transmission device for transmitting power from the power source to the drive wheels; a shift operating device operated by the driver to an operating position corresponding to the shift position of the power transmission device; and a parking lock mechanism which, based on the driver's operation of the shift operating device, is operated to switch the shift position to either a parking position in which the rotation of a rotating member that rotates with the drive wheels is mechanically prevented, or a non-parking position in which the rotation of the rotating member is permitted. A vehicle control device characterized by outputting torque from the power source in such a way that the load on the parking lock mechanism is reduced, based on one of a plurality of predetermined operations performed by the driver when requesting a switch of the shift position from the parking position to the non-parking position.

2. The vehicle control device according to claim 1, characterized in that the predetermined operation includes an operation to select a non-parking operation position corresponding to the non-parking position in the shift operation device, and a brake operation to activate the wheel brake.

3. The vehicle control device according to claim 2, characterized in that the predetermined operation further includes a preparatory operation that enables the shift operating device to operate to the non-parking operating position when the shift position is in the parking position.

4. The parking lock mechanism is operated to switch the shift position based on a control command signal corresponding to the driver's operation of the shift operating device. The shift operation device has an automatic return type operator that returns to its original position when no external force is applied, and has a plurality of positions in which the operator is operated relative to the original position, which are referred to as the operation positions. After the vehicle is operated to the non-parking position, a predetermined holding time has elapsed during which it can be determined that the time the vehicle remains continuously in the non-parking position is the operation intended by the driver. After this time, the parking lock mechanism begins to switch back to the non-parking position. The vehicle control device according to claim 2 or 3, characterized in that any one of the operations is an operation to select the non-parking operation position.

5. The parking lock mechanism is mechanically connected to the shift operating device and is operated in conjunction with the driver's operation of the shift operating device to switch the shift position. The vehicle control device according to claim 2 or 3, characterized in that any one of the operations is the brake operation.

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