Control device of vehicle

Abstract

To provide a control device of a vehicle for alleviating a burden of a driver's shift switching operation at evacuation from a rough road, in the control device of the vehicle having shift inhibit control.SOLUTION: When evacuation traveling from a rough road 40 is detected, a control device 90 of a vehicle 10 performs control for stopping an operation of shift inhibit control, or increasing prescribed values (VR at front traveling, VD at rear traveling) which are set in advance for starting the shift inhibit control. By this constitution, even if a shift operation is performed from a slip state of a drive wheel 14 at evacuation from a rough road, the shift inhibit control is not performed, the re-execution of a shift operation after the lowering of a vehicle speed V becomes unnecessary, and a handle operation even by both hands becomes easy. Therefore, a burden of a driver's operation at the evacuation from the rough road can be alleviated.SELECTED DRAWING: Figure 3

Description

[Technical field]

[0001] The present invention relates to a vehicle control device. [Background technology]

[0002] In controlling an automatic transmission mounted on a vehicle, there is a well-known vehicle control device that has a shift inhibit control that prohibits switching to the operated shift range when the shift lever is operated in the opposite driving direction while the vehicle is moving and the vehicle speed is higher than a predetermined value. For example, there is a vehicle control device described in Patent Document 1. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP 2014-19313 A

[0004] In a vehicle equipped with the shift inhibit control, when the shift lever is operated to move backward while traveling forward, if the vehicle speed is greater than the predetermined value, the shift inhibit control is implemented to set the shift range to the neutral range. When the vehicle speed drops below the predetermined value, the shift inhibit control is stopped. The same control is also implemented when the shift lever is operated to move forward while traveling backward. Summary of the Invention [Problem to be solved by the invention]

[0005] Incidentally, when the vehicle is to escape from a bad road such as a muddy road, the driving wheels are slipped to scrape off the mud on the road surface, and the road surface μ (friction coefficient) is increased, and then the rotation direction of the driving wheels is reversed, that is, the running direction of the vehicle is changed, thereby enabling the vehicle to escape. In addition, when the steering wheel is turned left and right to search for a place with high road surface μ, it is desirable to operate the steering wheel with both hands. However, when the vehicle speed is in a slip state greater than a predetermined value and the running direction of the vehicle is changed, the shift range is switched to the neutral range by the shift inhibit control, and the vehicle speed is reduced and a shift change operation is required again. As a result, the burden of the shift change operation increases, and it becomes difficult to operate the steering wheel with both hands.

[0006] The present invention has been made against the background of the above circumstances, and an object of the present invention is to provide a vehicle control device equipped with the shift inhibit control, which reduces the burden of driving operations when escaping from a rough road. [Means for solving the problem]

[0007] The gist of the present invention is that a control device for a vehicle includes (a) a power source, a power transmission device that transmits power from the power source to drive wheels, and a momentary shift operation device that is operated by a driver to switch the shift range of the power transmission device, and whose operator returns to a predetermined home position after operation, (b) performs shift inhibit control to switch the shift range to a neutral range when the shift operation device is operated in a driving direction opposite to the driving direction while driving, if the absolute value of the vehicle speed corresponding to the rotational speed of the drive wheels is greater than a predetermined value, and (c) detects escape from a rough road, and (d) when escape from the rough road is detected, performs control to stop operation of the shift inhibit control or increase the predetermined value. Effect of the Invention

[0008] According to the present invention, when the escape from the bad road is detected, the operation of the shift inhibit control is stopped or the predetermined value is increased. As a result, even if a shift switching operation is performed in a slipping state of the drive wheels when escaping the bad road, the shift inhibit control is unlikely to be activated, and it is not necessary to perform the shift switching operation again after the vehicle speed decreases, and it is easy to operate the steering wheel with both hands. Therefore, it is possible to provide a vehicle control device that reduces the burden of driving operations when escaping the bad road.

[0009] Preferably, the same effect can be obtained by using the actual vehicle speed, which is the moving speed of the vehicle itself, instead of the vehicle speed according to the rotation speed of the drive wheels. That is, it is possible to provide a vehicle control device that reduces the burden of driving operations when escaping from a rough road. [Brief description of the drawings]

[0010] [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 a control system for various controls in the vehicle. [Diagram 2] 2 is a diagram illustrating an example of the behavior of the vehicle in FIG. 1 when escaping from a rough road. FIG. [Diagram 3] 2 is a diagram for explaining the operation of shift inhibit control during driving in the shift control of the electronic control device of FIG. 1. FIG. [Figure 4] 4 is a time chart illustrating an example of an operation when escaping from a rough road in the shift control of the electronic control device of FIG. 1. [Diagram 5] FIG. 5 is a diagram for explaining another embodiment of the present invention, and is a time chart for explaining an example of operation when escaping from a rough road corresponding to FIG. 4. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0011] Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. EXAMPLES

[0012] 1 is a diagram illustrating a schematic configuration of a vehicle 10 to which the present invention is applied, and also illustrates main parts of control functions and a control system for various controls in the vehicle 10. 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.

[0013] The engine 12 is controlled by an engine control device 30 provided in the vehicle 10, and the torque of the engine 12, that is, the engine torque Te, is controlled.

[0014] The power transmission device 16 includes an automatic transmission 18 and a transmission shaft 20 (output shaft, propeller shaft, differential, left and right drive shafts, etc.). In the power transmission device 16, the power output from the engine 12 is transmitted to the drive wheels 14 via the transmission shaft 20 connected to the automatic transmission 18 connected to the engine 12.

[0015] The automatic transmission 18 is controlled by a hydraulic control circuit 32 provided in the vehicle 10, and shifting is performed in accordance with the accelerator opening θacc, the vehicle speed V, and the like.

[0016] In the vehicle 10, the shift range POSsh of the automatic transmission 18 is changed over using a shift-by-wire system. The shift range POSsh is, for example, P, R, N, D, and M ranges. The P range indicates the parking range of the vehicle 10, the R range indicates the reverse driving range of the vehicle 10, the N range indicates the neutral range of the vehicle 10, the D range indicates the forward driving range of the vehicle 10, and the M range indicates the manual shift range when the vehicle 10 is driving forward. The shift range POSsh of the automatic transmission 18 is synonymous with the shift range of the power transmission device 16.

[0017] The vehicle 10 further includes a shift operation device 50, a switching device 60, a shift range display meter 82 that notifies the driver of the shift range POSsh, and the like.

[0018] The shift operation device 50 is an operating device for selecting a shift range POSsh of the automatic transmission 18, and outputs an operating position signal POSop indicating the operating position at which the shift range POSsh is selected to the electronic control device 90. The operating position signal POSop indicates the operating position selected by operation of the shift lever 52 and P switch 54, which are operators of the shift operation device 50. Both the shift lever 52 and the P switch 54 are momentary type operators in which the operators return to a predetermined home position after operation. The shift operation includes P, R, N, D, M operations which correspond one-to-one to the P, R, N, D, M ranges of the shift range POSsh, and a return operation to the home position (referred to as an H operation).

[0019] The switching device 60 is a device that switches the shift range POSsh to the P range. In the P range, the power transmission of the automatic transmission 18 is interrupted, and the parking lock mechanism 64 fixes the transmission shaft 20 and the drive wheels 14 that rotate in conjunction with the transmission shaft 20 so that they cannot rotate.

[0020] The vehicle 10 includes an electronic control device 90 as a controller including a control device for the vehicle 10. The electronic control device 90 includes a so-called microcomputer.

[0021] The electronic control device 90 is supplied with various signals (e.g., operation position signal POSop, wheel speed No which is the rotation speed of the drive wheels 14, wheel speed Nws which is the rotation speed of the driven wheels, accelerator opening θacc, vehicle position information Ivp, setting signal Sset which is a signal indicating the driver's setting of rough road driving mode, differential lock, etc., vehicle-mounted camera image information Iard, etc.) based on detection values ​​by various sensors (e.g., shift operation device 50, rotation speed sensor 72 of the drive wheels 14, rotation speed sensor 74 of the driven wheels, wheel accelerator opening sensor 76, GPS position sensor 78, driving setting switch group 80, vehicle-mounted camera 84, etc.) provided in the vehicle 10. In addition, the vehicle speed V (Km / h) is obtained from the wheel speed No (rpm) of the drive wheels 14.

[0022] The electronic control unit 90 outputs various command signals (e.g., engine control command signal Se, transmission control command signal Sat, P range switching control command signal Splock, shift range display command signal POSdp, etc.) to each device (e.g., engine control unit 30, hydraulic control circuit 32, switching device 60, shift range display meter 82, etc.) provided in the vehicle 10.

[0023] The electronic control unit 90 functionally comprises a transmission control unit 94, a shift control unit 96, and a rough road exit detection unit 98.

[0024] The transmission control unit 94 determines the gear shift of the automatic transmission 18 using a gear shift map, which is a predetermined relationship, and outputs a transmission control command signal Sat to the hydraulic control circuit 32 as necessary.

[0025] The shift control unit 96 outputs a shift range command signal Spossh to the transmission control unit 94 so as to switch the shift range POSsh based on a shift operation, and also outputs a P range switching control command signal Splock to the switching device 60 when switching to the P range.

[0026] In addition, the shift control unit 96 detects whether the absolute value of the vehicle speed V is a predetermined value (V R or V D ), shift inhibit control is performed to switch the shift range POSsh to the N range.

[0027] FIG. 3(a) is a diagram for explaining the operation of the shift inhibit control during driving. The bold framed portion of FIG. 3(a) is the region in which the shift inhibit control operates. For example, when the R operation is performed during forward driving, the absolute value of the vehicle speed V reaches a predetermined value V R If the absolute value of the vehicle speed V is greater than the predetermined value V, the shift inhibit control is activated to switch the shift range POSsh to the N range. DIf it is greater than , the shift range POSsh is switched to the N range.

[0028] However, the conventional shift inhibit control has a problem in driving operation when the vehicle 10 is caused to escape from a bad road 40 such as a muddy road. FIG. 2 is a diagram for explaining an example of the behavior of the vehicle 10 when the vehicle is caused to escape from the bad road 40. In FIG. 2, when the vehicle 10 is caused to escape from the bad road 40, for example, forward driving is performed (see arrow A), the driving wheels 14 are slipped to scoop out mud on the road surface, and the road surface μ (friction coefficient) is increased, and then the rotation direction of the driving wheels 14 is reversed, that is, the vehicle is switched to reverse driving (D → R) (see arrow B), and the vehicle is attempted to escape to the left side of the paper. If escape is not possible, the rotation direction of the driving wheels 14 is reversed again, that is, the vehicle is switched to forward driving (R → D) (see arrow C), and the vehicle is attempted to escape to the right side of the paper. Such escape driving is repeated. In addition, during escape driving, it is desirable to operate the steering wheel with both hands in order to search for a place with high road surface μ while turning it left and right. However, when the absolute value of the vehicle speed V is a predetermined value (forward travel V R , V when driving in reverse D ), if a shift operation is performed in the opposite direction to the direction of travel, the shift inhibit control is activated, the shift range POSsh is switched to N range, and the absolute value of the vehicle speed V reaches a predetermined value (V R , V when driving in reverse D ) or lower, shifting is required again. This results in increased strain on the driver when shifting gears, and also makes it difficult to operate the steering wheel with both hands.

[0029] Therefore, in the present embodiment, when a bad road escape detection unit 98 described later detects that the vehicle has escaped from the bad road, the shift control unit 96 changes the operation to that shown in FIG. 3B (see the bold frame). In FIG. 3B, when the R operation is performed during forward travel, the absolute value of the vehicle speed V reaches a predetermined value V R If the absolute value of the vehicle speed V is greater than the predetermined value V, the power transmission of the automatic transmission 18 is interrupted. R After the absolute value of the vehicle speed V falls below a predetermined value V, the shift range POSsh is switched to the R range. Similarly, when the D operation is performed while driving in reverse, DIf the absolute value of the vehicle speed V is greater than the predetermined value V, the power transmission of the automatic transmission 18 is interrupted. D When the vehicle speed V drops below this value, the shift range POSsh is switched to D range. This eliminates the need to shift gears again after the vehicle speed V drops, making it easier to operate the steering wheel with both hands. This reduces the burden of driving when escaping rough roads.

[0030] The bad road escape detection unit 98 detects the vehicle 10 escaping from the bad road. The detection of the bad road escape is preferably performed based on whether any one or more of the following six judgments are satisfied. The first is a slip judgment, which is determined based on whether or not the difference between the wheel speed No of the driving wheels 14 and the wheel speed Nws of the driven wheels exceeds a predetermined judgment threshold for judging tire slip. The second is a selection of a bad road traveling mode by the driver, which is determined based on whether or not the bad road traveling mode is set in the traveling setting switch group 80 when traveling on a muddy road with a low road surface μ (friction coefficient). The third is a differential lock, which is determined based on whether or not the differential lock is set in the traveling setting switch group 80. The fourth is a comparison between the displacement of the vehicle position obtained from the GPS information and the vehicle speed V, which is determined based on whether or not there is a displacement of the vehicle position of the vehicle position information Ivp from the GPS position sensor 78 with respect to the vehicle speed V, for example. The fifth is a comparison of the vehicle speed obtained from the GPS information with the vehicle speed V, for example, whether or not the difference between the rate of change of the vehicle position information Ivp from the GPS position sensor 78 and the vehicle speed V exceeds a predetermined judgment threshold. The sixth is a road surface image judgment, and whether or not the road surface condition is bad is judged from the on-board camera image information Iard of the on-board camera 84.

[0031] Fig. 4 is a time chart for explaining an example of control operation (corresponding to the driving state from arrow A to arrow B in Fig. 2) when escaping from a bad road in the shift control of the electronic control device 90 of this embodiment. Fig. 4(a) shows a case where the present invention is not applied, and Fig. 4(b) shows a case where the present invention is applied.

[0032] In FIG. 4A, first, at time t1, forward driving is started, and the driving torque Tr and the vehicle speed V increase. Next, at time t2, the shift lever 52 is operated in the R direction, but the absolute value of the vehicle speed V reaches a predetermined value V R Since the shift inhibit control is activated, the shift range POSsh is switched to the N range, and the N range is displayed on the shift range display meter 82. To switch to reverse driving from this state, the absolute value of the vehicle speed V must be greater than or equal to a predetermined value V R At time t3, when the vehicle speed V becomes lower than the time t1, the shift lever 52 must be operated in R again, or the shift lever 52 must be kept in R until the time t3. Then, at time t3, the shift range POSsh is switched to the R range and reverse driving is started, and at time t4 when reverse driving (driving torque Tr and vehicle speed V) becomes stable, the vehicle can escape from the rough road 40.

[0033] In FIG. 4B, first, at time t0, the bad road exit detection unit 98 detects that the vehicle has exited the bad road, and the bad road exit detection flag is turned ON. Next, at time t1, forward travel is started, and the drive torque Tr and vehicle speed V increase. Next, at time t2, when the shift lever 52 is operated in the R direction, the absolute value of the vehicle speed V reaches a predetermined value V. R However, because the bad road exit detection flag is ON, the switch to the R range is accepted and the R range is displayed on the shift range display meter 82. Then, the power transmission of the automatic transmission 18 is interrupted, and when the absolute value of the vehicle speed V reaches the predetermined value V R At time t31, when the vehicle speed V is below the threshold, the shift range POSsh is switched to the R range and reverse driving begins. Then, at time t4, when reverse driving (driving torque Tr and vehicle speed V) is stabilized, the vehicle attempts to escape from the rough road 40. This eliminates the need to perform a second shift operation after the vehicle speed V has decreased, and makes it easier to operate the steering wheel with both hands. This reduces the operational burden on the driver when escaping from the rough road.

[0034] In addition, in the case where the rough road escape detection unit 98 detects the escape of the rough road by the driver's differential lock setting, even if the driver forgets to release the differential lock after escaping the rough road, the driver will feel an uncomfortable sensation when turning after escaping the rough road and will realize that he or she has forgotten to release the differential lock, so the inhibition control will not be stopped for longer than necessary.

[0035] In this embodiment, the threshold value for determining whether or not to activate the shift inhibit control at time t2 is set to a predetermined value V R However, when the bad road exit detection flag is ON, the predetermined value V R The increased value of V R 1, the same operation and effect as the example of FIG. 4(b) can be obtained by disabling the shift inhibit control. D A given value V increased from D will be changed to 1.

[0036] As described above, according to this embodiment, when it is detected that the vehicle is escaping from the bad road 40, the operation of the shift inhibit control is stopped or the shift inhibit control is increased to a predetermined value (V R , V when driving in reverse D ) is increased. As a result, even if a shift operation is performed when the drive wheels 14 are in a slipping state when escaping a rough road, the shift inhibit control does not operate, and there is no need to perform a shift operation again after the vehicle speed V has decreased, making it easier to operate the steering wheel with both hands. Therefore, it is possible to provide a control device 90 for the vehicle 10 that reduces the operational burden on the driver when escaping a rough road.

[0037] Next, another embodiment of the present invention will be described. In the following description, parts common to the embodiments are given the same reference numerals and the description thereof will be omitted. EXAMPLES

[0038] FIG. 5 shows an embodiment in which the actual vehicle speed Va, which is the moving speed of the vehicle itself, is used instead of the vehicle speed V in the shift inhibit control. The actual vehicle speed Va is obtained, for example, from the rate of change of the vehicle position information Ivp from the GPS position sensor 78, the wheel speed Nws of the driven wheels, etc. First, at time t1, forward driving is started, and the drive torque Tr and vehicle speed V increase. Next, at time t2, when the shift lever 52 is operated in the R direction, the absolute value of the actual vehicle speed Va becomes equal to or exceeds the predetermined value V on the muddy road. R Since the vehicle speed V is equal to or less than the predetermined value V, the shift to the R range is accepted and the R range is displayed on the shift range display meter 82. Then, the power transmission of the automatic transmission 18 is interrupted and the absolute value of the vehicle speed V reaches the predetermined value V R At time t31, the shift range POSsh is switched to the R range and reverse driving is started. Then, at time t4, when reverse driving (driving torque Tr and vehicle speed V) becomes stable, the vehicle attempts to escape from the rough road 40.

[0039] As described above, according to this embodiment, the same effects as those of the above-mentioned first embodiment can be obtained.

[0040] Although the embodiment of the present invention has been described in detail above with reference to the drawings, the present invention can be applied to other embodiments.

[0041] It should be noted that the above is merely one embodiment, and the present invention can be embodied in various modified and improved forms based on the knowledge of those skilled in the art. [Explanation of symbols]

[0042] 10: vehicle 12: engine (power source) 14: drive wheels 16: power transmission device 40: rough road 50: shift operation device 90: electronic control device (control device) V: vehicle speed V R :Predetermined value V D :Predetermined value

Claims

[Claim 1] A control device for a vehicle including a power source, a power transmission device that transmits power from the power source to drive wheels, and a momentary shift operation device that is operated by a driver to switch a shift range of the power transmission device, and whose operator returns to a predetermined home position after the operation, a shift inhibit control for switching the shift range to a neutral range when an absolute value of a vehicle speed corresponding to a rotation speed of the drive wheels is greater than a predetermined value when the shift operation device is operated in a driving direction opposite to a driving direction while the vehicle is traveling; and detecting escape travel from a rough road. A vehicle control device comprising: a control unit that, when it is detected that the vehicle is escaping from a bad road, stops the operation of the shift inhibit control, or executes control to increase the predetermined value.

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