阅读说明：本技术 车辆控制装置 (Vehicle control device ) 是由 大岛达也 西村伸之 于 2018-05-10 设计创作，主要内容包括：车辆控制装置(10)包括：前方挡位选择部(16),根据车辆(V)的多个挡位每个的驱动力特性以及与前方行驶区间对应的行驶阻力特性,选择前方行驶区间中的车辆(V)的挡位即前方挡位；以及换挡控制部(17),根据前方挡位,控制前方行驶区间的车辆(V)的挡位的换挡。在车辆(V)的行驶模式为优先抑制燃料消耗量而行驶的第一模式的情况下,前方挡位选择部(16)选择驱动力特性所示的驱动力为行驶阻力特性的行驶阻力以上的车辆的速度中的最低速度即可行驶最低车速为最高的挡位作为前方挡位,在车辆(V)的行驶模式为优先提高行驶性能而行驶的第二模式的情况下,前方挡位选择部(16)选择该驱动力为该行驶阻力以上的车辆(V)的速度中的最高速度即可行驶最高车速为最高的挡位作为前方挡位。(A vehicle control device (10) is provided with: a forward range selection unit (16) that selects a forward range, which is a range of the vehicle (V) in a forward travel range, on the basis of a driving force characteristic of each of a plurality of ranges of the vehicle (V) and a travel resistance characteristic corresponding to the forward travel range; and a shift control unit (17) that controls shifting of the shift position of the vehicle (V) in the forward travel section according to the forward shift position. When the running mode of the vehicle (V) is a first mode for running with priority given to fuel consumption suppression, the front range selection unit (16) selects, as a front range, a range in which the lowest speed, i.e., the lowest vehicle speed, that is the lowest speed among the speeds of the vehicle at or above the running resistance for which the driving force indicated by the driving force characteristic is a running resistance characteristic, i.e., the lowest vehicle speed, is the highest, and when the running mode of the vehicle (V) is a second mode for running with priority given to improvement of the running performance, the front range selection unit (16) selects, as a front range, a range in which the highest speed, i.e., the highest vehicle speed, that is the highest, among the speeds of the vehicle (V) for.)

1. A vehicle control apparatus comprising:

a travel section determination unit configured to determine a forward travel section that is ahead in a forward direction of the vehicle and has a road gradient different from a current travel section in which the vehicle is traveling;

a forward range selection unit that selects a forward range, which is a range of the vehicle in the forward travel range, based on a driving force characteristic indicating a relationship between a speed of the vehicle and a driving force of the vehicle for each of a plurality of ranges of the vehicle and a travel resistance characteristic indicating a relationship between the speed of the vehicle and a travel resistance of the vehicle corresponding to the forward travel range; and

a shift control unit that controls shifting of the shift range of the vehicle in the forward travel section in accordance with the forward shift range selected by the forward shift range selection unit,

the forward range selection unit selects, as the forward range, a range in which a lowest vehicle speed is highest, which is a range in which a driving force indicated by the driving force characteristic becomes a lowest speed among speeds of the vehicle equal to or higher than a running resistance indicated by the running resistance characteristic, i.e., a lowest vehicle speed, when the running mode of the vehicle is a first mode in which the vehicle runs with priority being given to suppression of a fuel consumption amount, and selects, as the forward range, a range in which a highest vehicle speed is highest, which is a highest speed among speeds of the vehicle equal to or higher than the running resistance indicated by the running resistance characteristic, i.e., a driving force indicated by the driving force characteristic becomes a highest speed, which is a highest among speeds of.

2. The vehicle control apparatus according to claim 1,

when the forward range selected by the forward range selection unit is lower than a current range that is a range of a vehicle in a current running state of the vehicle, the shift control unit controls shifting of the range such that a downshift is performed from the current range to the forward range if the vehicle is within a predetermined range with reference to a start position of the forward running section.

3. The vehicle control apparatus according to claim 1 or 2,

further comprising a current shift selection section that selects a current shift that is a shift of the vehicle in a current running state of the vehicle according to a running resistance of the vehicle,

in a case where the current gear selection portion newly selects a target gear that is lower than the current gear while the vehicle is traveling in the current travel section in the current gear,

the shift control unit controls shifting of the gear so that the current gear is maintained while suppressing a downshift from the current gear to the target gear when a stall amount of the vehicle when the vehicle is traveling in the current travel section is equal to or less than a predetermined threshold value while the vehicle is able to travel in the forward travel section in the current gear due to a driving force of the vehicle corresponding to the current gear exceeding a travel resistance of the vehicle in the forward travel section,

the shift control portion controls shifting of the gear so that the downshift is not inhibited but the downshift from the current gear to the target gear in a case where the forward gear selected by the forward gear selection portion is lower than the current gear.

Technical Field

The present disclosure relates to a vehicle control device.

Background

The following technical scheme is proposed: a shift schedule table (change speed ス ケ ジ ュ ー ル) that minimizes the amount of fuel consumption in a travel route is set based on road information on the travel route from the current position of the vehicle to the target position and the driving force of the vehicle on the travel route (see, for example, patent document 1).

[ Prior art documents ]

[ patent document ]

Patent document 1: japanese patent application laid-open No. Hei 9-21457

Disclosure of Invention

[ problem to be solved by the invention ]

However, there are cases where there are a first mode that prioritizes fuel consumption and a second mode that prioritizes traveling performance in the vehicle. If the vehicle selects the shift position in the same manner in each mode, there is a problem that running suitable for each mode cannot be performed.

In particular, if the vehicle selects a shift position in the forward travel range ahead in the forward direction in each mode in the same manner, and shifts to the shift position selected when entering the forward travel range, such a problem arises: the speed is less than the state assumed in the priority traveling performance mode, or the fuel consumption amount is more than the state assumed in the priority fuel consumption mode.

Therefore, the present disclosure has been made in view of these problems, and an object thereof is to provide a vehicle control device capable of selecting a shift position adapted to a running mode of a vehicle.

[ means for solving the problems ]

One aspect of the present disclosure is a vehicle control device. The device includes: a travel section determination unit configured to determine a forward travel section that is ahead in a forward direction of the vehicle and has a road gradient different from a current travel section in which the vehicle is traveling; a forward range selection unit that selects a forward range, which is a range of the vehicle in the forward travel range, based on a driving force characteristic indicating a relationship between a speed of the vehicle and a driving force of the vehicle for each of a plurality of ranges of the vehicle and a travel resistance characteristic indicating a relationship between the speed of the vehicle and a travel resistance of the vehicle corresponding to the forward travel range; and a shift control unit that controls shifting of the shift range of the vehicle in the forward travel section in accordance with the forward shift range selected by the forward shift range selection unit, in the case where the running mode of the vehicle is the first mode in which the vehicle runs with priority given to suppression of the fuel consumption amount, the forward range selection unit selects, as the forward range, a range in which a lowest vehicle speed that is the lowest vehicle speed that can be traveled, among the speeds of the vehicle in which the driving force indicated by the driving force characteristic is equal to or higher than the travel resistance indicated by the travel resistance characteristic, is the highest, in the case where the running mode of the vehicle is the second mode in which running is performed with priority given to improvement of running performance, the forward range selection unit selects, as the forward range, a range in which a maximum vehicle speed can be highest, which is a highest speed among speeds of the vehicle in which the driving force indicated by the driving force characteristic is equal to or higher than the running resistance indicated by the running resistance characteristic.

When the forward range selected by the forward range selection unit is lower than a current range that is a range of the vehicle in the current running state of the vehicle, and the vehicle is located within a predetermined range with reference to a start position of the forward running section, the shift control unit may control shifting of the range such that a downshift is performed from the current range to the forward range.

The vehicle control device may further include a current shift range selection unit that selects a current shift range, which is a shift range of the vehicle in a current running state of the vehicle, based on a running resistance of the vehicle, and the shift control unit may control the shift range so that a downshift from the current shift range to the target shift range is suppressed, when the driving force of the vehicle corresponding to the current shift range exceeds the running resistance of the vehicle in the preceding running range, so that the vehicle can run in the current shift range, and when a stall amount of the vehicle when the vehicle runs in the current running range in the current shift range is equal to or less than a predetermined threshold value, the current shift range selection unit selects a current shift range, which is a shift range of the vehicle in the current running state, based on the running resistance of the vehicle, and when the current shift range selection unit newly selects the target shift range that is lower than the current shift range, While maintaining the current gear.

[ Effect of the invention ]

According to the present disclosure, an effect is achieved that a shift position suitable for a running mode of a vehicle can be selected.

Drawings

Fig. 1 is a diagram showing an outline of a vehicle according to an embodiment.

Fig. 2 is a diagram schematically showing an internal structure of the vehicle of the embodiment.

Fig. 3 is a diagram showing the configuration of a vehicle control device of the embodiment.

Fig. 4 is a running performance diagram of the vehicle according to the embodiment.

Fig. 5 is a diagram showing a part of the running performance diagram shown in fig. 4.

Fig. 6 is a flowchart for explaining the flow of processing relating to the early downshift control executed by the vehicle control device according to the embodiment.

Fig. 7 is a flowchart for explaining the flow of processing relating to the downshift control executed by the vehicle control device according to the embodiment.

Detailed Description

[ overview of vehicle of embodiment ]

Referring to fig. 1, an outline of a vehicle V according to the embodiment is described.

Fig. 1 is a diagram showing an outline of a vehicle V according to the embodiment.

The vehicle V travels in any one of the economy mode as the first mode and the power mode as the second mode. The economy mode is a mode in which the vehicle V travels while suppressing the fuel consumption amount of the vehicle V with priority. The power mode is a mode in which the vehicle V travels with priority given to improvement of the traveling performance of the vehicle V.

The vehicle V selects a current shift position, which is a shift position of the vehicle V in its current running state (hereinafter, referred to as a current running state), and selects a forward shift position, which is a shift position of the vehicle V in a forward running section ahead in the forward direction. When the vehicle V selects the current gear and the forward gear, the gear is selected in different manners in each of the economy mode and the power mode. In this way, the vehicle V can select a shift position that is appropriate for the running mode of the vehicle. Next, the vehicle V will be described in detail.

[ Structure of vehicle of embodiment ]

Referring to fig. 2, a structure of a vehicle V according to the embodiment will be described.

Fig. 2 is a diagram schematically showing an internal structure of the vehicle V of the embodiment. The vehicle V of the embodiment includes an engine 1, a transmission 2, a GPS (Global Positioning System) sensor 3, a weight sensor 4, a speed sensor 5, an accelerator opening sensor 6, and a vehicle control device 10.

The vehicle V is a large vehicle using an engine 1 such as a diesel engine as a driving force, and particularly a vehicle equipped with an auto cruise mode. The transmission 2 transmits the rotational driving force of the engine 1 to a driving wheel (not shown) of the vehicle V. The transmission 2 includes gears of multiple stages for converting the rotational driving force of the engine 1.

Here, the "automatic cruise mode" of the vehicle V is a mode in which the engine 1, the transmission 2, and the like are automatically controlled by the vehicle control device 10, and the driver maintains a preset speed of the vehicle V without operating the accelerator or the shift lever. The auto cruise mode is mainly assumed to be used when the vehicle V is running on a high road.

The GPS sensor 3 receives and analyzes radio waves transmitted from a plurality of navigation satellites, and thereby obtains the position of the GPS sensor 3, that is, the position of the vehicle V on which the GPS sensor 3 is mounted. The GPS sensor 3 outputs information indicating the position of the vehicle V to the vehicle control device 10.

The weight sensor 4 acquires the total weight of the vehicle V. Specifically, the weight sensor 4 measures the weight of the load of the vehicle V, and adds the weight to the weight of the vehicle V alone excluding the load to obtain the total weight of the vehicle V. The weight sensor 4 outputs information indicating the total weight of the vehicle V to the vehicle control device 10.

The speed sensor 5 measures the speed of the vehicle V. The speed sensor 5 outputs information indicating the measured speed to the vehicle control device 10. The accelerator opening sensor 6 measures an accelerator opening, which is an amount by which a driver of the vehicle V steps on an accelerator pedal. The accelerator opening sensor 6 outputs information indicating the accelerator opening to the vehicle control device 10.

The vehicle control device 10 acquires information from the above-described sensors, and controls the amount of fuel supplied to the cylinder in the engine 1 and the shift position of the transmission 2 based on the acquired information. The vehicle control device 10 controls the engine 1 and the transmission 2 so that the vehicle V travels maintaining the set speed in the case where the vehicle V is in the auto cruise mode. In addition, the vehicle control Device 10 controls the engine 1 and the transmission 2 so that the Speed of the vehicle V does not exceed the set upper Limit Speed when a Speed Limit Device (SLD) of the vehicle V is operated.

In addition, when the vehicle V is in the economy mode, the vehicle control device 10 controls the engine 1 and the transmission 2 by giving priority to reduction in the fuel consumption amount. When the vehicle V is in the power mode, the vehicle control device 10 controls the engine 1 and the transmission 2 by giving priority to improvement of the running performance of the vehicle V.

[ Structure of vehicle control device 10 of the embodiment ]

Next, the configuration of the vehicle control device 10 according to the embodiment will be described with reference to fig. 3.

Fig. 3 is a diagram showing the configuration of the vehicle control device 10 of the embodiment. The vehicle control device 10 of the embodiment includes a storage unit 11 and a control unit 12.

The storage unit 11 is, for example, a ROM (Read Only Memory) or a RAM (Random Access Memory). The storage unit 11 stores various programs for causing the control unit 12 to function.

The control Unit 12 is a computing resource including a processor such as a CPU (Central Processing Unit) not shown. The control unit 12 implements the functions of the current gear selection unit 13, the road gradient acquisition unit 14, the travel section determination unit 15, the forward gear selection unit 16, and the shift control unit 17 by executing the program stored in the storage unit 11.

The current gear selection unit 13 calculates a net average effective pressure PmeR of the engine 1 corresponding to a running resistance of the current running state of the vehicle V at predetermined time intervals, and calculates a net average effective pressure Pme of each gear based on the calculated net average effective pressure PmeR. The net mean effective pressure Pme for each gear is the minimum torque required to maintain the current driving state. The current gear selection unit 13 selects a current gear, which is a gear of the transmission 2 in the current running state of the vehicle V, by referring to the iso-fuel consumption map and the maximum torque map PmeMAX, using the calculated net average effective pressure Pme of each gear and the engine speed when shifting to each gear.

Specifically, first, the current gear selection unit 13 calculates the net average effective pressure PmeR of the engine 1 corresponding to the running resistance in the current running state. The current gear selection section 13 calculates a net mean effective pressure Pme of the engine 1 based on the torque generated by the engine 1. The current gear selection unit 13 calculates a net average effective pressure PmeR corresponding to the running resistance of the engine 1 from the calculated net average effective pressure Pme, the vehicle weight, the gear ratio of the gear selected by the transmission 2, the final reduction ratio, the transmission efficiency, the engine exhaust gas amount, the drive wheel radius, and the acceleration of the vehicle V. The current gear selection unit 13 calculates a net average effective pressure Pme, which is the lowest torque required to maintain the current running state in each gear, and the engine speed based on the calculated net average effective pressure PmeR, and creates an iso-horsepower map. The current gear selection unit 13 selects a gear with the best fuel efficiency by referring to the iso-horsepower map, the maximum torque map PmeMAX, and the iso-fuel consumption map. The current gear selection unit 13 may calculate the net average effective pressure PmeR corresponding to the running resistance from the road gradient of the road on which the vehicle V is running, which is obtained by the road gradient acquisition unit 14.

The road gradient acquisition unit 14 acquires the road gradient of the road on which the vehicle V is traveling, based on the information indicating the position of the vehicle V obtained from the GPS sensor 3 and the map information stored in the storage unit 11. For example, the road gradient acquisition unit 14 acquires the road gradient from the position of the vehicle V to a predetermined distance (e.g., 500m) ahead.

The travel section determination unit 15 determines a forward travel section that is ahead of the vehicle V in the traveling direction and has a road gradient different from the current travel section in which the vehicle V is currently traveling, based on the road gradient obtained by the road gradient acquisition unit 14.

The forward range selection unit 16 selects a forward range, which is a gear position of the transmission 2 in the forward travel section, according to a road gradient in the forward travel section. Specifically, first, the forward range selection unit 16 calculates the travel resistance in the forward travel section from the rolling resistance of the drive wheels of the vehicle V, the air resistance of the vehicle V, and the gradient resistance in the forward travel section.

Next, the front range selection unit 16 determines the front range based on the driving force characteristic information indicating the relationship between the speed of each of the plurality of ranges of the vehicle V and the driving force of the vehicle V stored in the storage unit 11 and the calculated running resistance in the front running section.

Fig. 4 is a running performance diagram of the vehicle V corresponding to the driving force characteristic information of the embodiment. Fig. 4 shows driving force characteristics G2 to G12 indicating the relationship between the driving force and the speed of the vehicle V in each of the plurality of shift stages 2 nd to 12 th. Fig. 4 shows a running resistance characteristic R indicating a relationship between the speed and the running resistance of the vehicle V corresponding to the forward running section. Fig. 5 is a diagram showing a part of the running performance diagram shown in fig. 4. In fig. 5, driving force characteristics G9 and G10 of the 9 th and 10 th gears, and a running resistance characteristic R corresponding to a forward running section are shown.

The forward range selection unit 16 selects, as the forward range, a range in which the driving force of the vehicle V is larger than the running resistance of the vehicle V in the forward running section, based on the driving force characteristics corresponding to each of the plurality of ranges.

Here, the forward range selection unit 16 selects the shift range based on different modes when the running mode of the vehicle V is the economy mode and when the running mode is the power mode. First, an example of selecting a shift range in the economy mode will be described.

When the running mode of the vehicle V is the economy mode, the front range selection unit 16 determines the lowest speed, i.e., the lowest vehicle speed, among the speeds at which the vehicle V can run, for each of the plurality of ranges in which the vehicle V can run in the front running section.

Specifically, the front range selection unit 16 determines, as the lowest travelable vehicle speed, the lowest speed among the speeds of the vehicle V at which the driving force indicated by the driving force characteristic becomes equal to or greater than the travel resistance indicated by the travel resistance characteristic corresponding to the front travel section, for the driving force characteristic of each of the plurality of ranges. The front range selection unit 16 determines the lowest travelable vehicle speed as the lower speed of the speeds at which the driving force indicated by the driving force characteristic and the travel resistance indicated by the travel resistance characteristic match. The front range selection unit 16 determines the lowest speed of the vehicle V indicated by the driving force characteristic as the lowest vehicle speed that can be traveled when the driving force and the running resistance do not match each other because the driving force exceeds the running resistance in each speed. In the example shown in fig. 5, the forward range selection unit 16 determines the lowest vehicle speed capable of traveling as 18km/h with respect to the 8 th range.

The forward range selection unit 16 selects, as a forward range, a range (highest possible-to-travel range) having the highest lowest possible vehicle speed and low driving force characteristics from among a plurality of ranges. Thus, the front range selection unit 16 can select the highest drivable range in the eco mode.

For example, the forward range selection unit 16 selects a range equal to or lower than the 10 th range as a range in which the vehicle can travel in the forward travel section. Regarding the 9 th gear, the front range selection portion 16 determines, as the travelable minimum vehicle speed, the lower speed of the speeds of the vehicle V when the driving force indicated by the driving force characteristic and the travel characteristic indicated by the travel resistance characteristic R corresponding to the front travel section coincide. In the example shown in fig. 5, the front range selection unit 16 determines the lowest vehicle speed that can be driven to be 28 km/h. Similarly, regarding the 10 th gear, the front gear selection portion 16 determines the lowest vehicle speed that can be driven to be 40 km/h. Of the lowest vehicle speeds that can be driven and are determined for the respective gears equal to or lower than the 10 th gear, the front gear selection unit 16 selects the 10 th gear, which is the gear having the highest speed and low driving force characteristics, as the front gear.

Further, when the traveling mode of the vehicle V is the power mode, the front range selection unit 16 specifies the highest speed, that is, the highest traveling vehicle speed, among the speeds at which the vehicle V can travel, for each of the plurality of ranges in which the vehicle V can travel in the front traveling zone.

Specifically, in the case of the power mode, the forward range selection unit 16 determines, as the highest travelable vehicle speed, the highest speed among the speeds of the vehicle V at which the driving force indicated by the driving force characteristic becomes equal to or greater than the traveling characteristic indicated by the traveling resistance characteristic corresponding to the forward traveling zone, with respect to the driving force characteristic of each of the plurality of ranges. The forward range selection unit 16 determines the highest travelable vehicle speed as the higher speed of the speeds at which the driving force indicated by the driving force characteristic and the travel resistance indicated by the travel resistance characteristic match. When the driving force and the running resistance do not match each other because the driving force exceeds the running resistance in each speed, the front range selection unit 16 determines the highest speed of the vehicle V indicated by the driving force characteristic as the maximum travelable vehicle speed. For example, for the 8 th gear, the front shift selection unit 16 determines the highest vehicle speed that can be driven to 59 km/h.

Among the plurality of shift stages, the front shift stage selecting section 16 selects, as the front shift stage, a shift stage having the highest possible vehicle speed and high driving force characteristics (the highest possible travel shift stage). Thus, the front range selection unit 16 can select the highest-speed travelable range in the power mode.

For example, the forward range selection unit 16 selects the 10 th or lower range as the drivable range. Regarding the 9 th gear, the front range selection portion 16 determines, as the travelable maximum vehicle speed, the higher speed of the speeds of the vehicle V when the driving force indicated by the driving force characteristic and the travel characteristic indicated by the travel resistance characteristic R corresponding to the front travel section coincide. In the example shown in fig. 5, the front range selection unit 16 determines the highest possible vehicle speed to be 87 km/h. Similarly, regarding the 10 th gear, the front gear selection unit 16 determines the highest vehicle speed that can be driven to 82 km/h. The forward range selection unit 16 selects, as the forward range, the 9 th range, which is a range having high driving force characteristics and the highest speed among the highest possible-to-travel vehicle speeds determined for the ranges equal to or lower than the 10 th range.

The shift control unit 17 calculates the speed when entering the forward travel section and the travel resistance of the vehicle V in the forward travel section. In order to calculate the speed when entering the forward travel section, the shift control unit 17 refers to the driving force characteristic information of the vehicle V stored in the storage unit 11, and thereby determines the driving force of the vehicle V at the current speed. Further, the shift control portion 17 calculates the running resistance at the current speed of the current running section. The shift control portion 17 calculates the acceleration of the vehicle V based on the difference between the determined driving force and the running resistance, and the total weight of the vehicle V obtained by the weight sensor 4. Here, when the running resistance exceeds the driving force of the vehicle V, the acceleration of the vehicle V becomes a negative value. The shift control unit 17 calculates the amount of change in the speed of the vehicle V from the current position of the vehicle V to the start position of the preceding travel section, based on the calculated acceleration of the vehicle V and the remaining distance of the current travel section. In the embodiment, the current travel section is assumed to be an uphill section, and therefore the stall amount of the vehicle V is calculated. The shift control unit 17 calculates the speed of the vehicle V when entering the forward travel section by subtracting the shift loss amount from the current speed of the vehicle V.

The shift control unit 17 estimates the running resistance of the vehicle V in the forward running section from the road gradient in the forward running section. The shift control unit 17 calculates a running resistance characteristic of the forward running section from rolling resistance of the driving wheels of the vehicle V, air resistance of the vehicle V, and gradient resistance of the forward running section.

[ Shift control based on the front range selected by the front range selection unit 16 ]

When the vehicle V is located within a predetermined range from the boundary between the current travel range and the preceding travel range, the shift control unit 17 controls shifting of the shift range of the vehicle V in the preceding travel range according to the preceding shift range selected by the preceding shift range selection unit 16.

Specifically, when the front gear selected by the front gear selection unit 16 is lower than the current gear that is the current gear of the vehicle V, the shift control unit 17 controls shifting of the gears so as to downshift from the current gear to the front gear. More specifically, when the selected forward range is 2 or more lower than the current range, the shift control unit 17 downshifts from the current range to the forward range if the vehicle V is located within a predetermined range with reference to the start position of the forward travel range.

In the case where the running mode of the vehicle V is the power mode, the front range selection portion 16 tends to select a range lower than that in the economy mode. Therefore, when the running mode of the vehicle V is the power mode, the frequency with which the forward range selected by the forward range selecting unit 16 is lower than the current range by 2 or more increases, and the number of times of downshift control by the shift control unit 17 increases, as compared with the economy mode. In this way, when the running mode of the vehicle V is the power mode, the vehicle control device 10 can improve the running performance as compared to the economy mode.

[ Shift control based on the current gear selected by the current gear selection section 13 ]

The shift control unit 17 controls shifting of the shift position of the vehicle V in the current travel section according to the current shift position selected by the current shift position selection unit 13. For example, when the current gear selection unit 13 newly selects the target gear that is lower than the current gear while the vehicle V is traveling in the current travel section in the current gear, the shift control unit 17 determines whether or not the vehicle V can travel in the travel section ahead in the current gear. Specifically, the shift control unit 17 determines whether or not the vehicle can travel in the forward travel range by the current shift position, based on whether or not the maximum value of the driving force corresponding to the current shift position exceeds the travel resistance in the forward travel range.

Further, the shift control portion 17 calculates the stall amount of the vehicle V when running in the current running section in the current gear. Then, the shift control unit 17 determines whether or not the calculated stall amount is equal to or less than a predetermined threshold value. Here, the predetermined threshold value is a value set according to the speed of the current vehicle V. When the vehicle can travel in the forward travel range with the current gear and the calculated shift loss amount is equal to or less than the predetermined threshold value, the shift control unit 17 controls shifting of the gear of the transmission 2 so that the current gear is maintained while suppressing a downshift from the current gear to the target gear. When the vehicle cannot travel in the forward travel range with the current gear or when the calculated stall amount is larger than a predetermined threshold value, the shift control unit 17 controls shifting of the gear of the transmission 2 so as to downshift from the current gear to the target gear.

[ Exception of inhibiting downshift ]

The shift control unit 17 performs control relating to the downshift suppression control exception. Even when the state of the vehicle V satisfies a predetermined condition while the downshift is being suppressed, the shift control unit 17 controls the shift of the shift stage of the transmission 2 so as to downshift to the target shift stage without suppressing the downshift. Next, details of an exception to the downshift suppression will be described.

[ Exception 1 for suppressing downshift ]

The shift control unit 17 calculates the lowest rotation speed of the engine 1 when the vehicle travels in the current travel section in the current gear. Here, the speed at which the vehicle V enters the preceding travel section becomes the lowest speed of the vehicle V in the current travel section. The shift control unit 17 calculates the lowest rotation speed of the engine 1 when the vehicle V travels in the current running section in the current gear, based on the lowest speed of the vehicle V in the current running section. The shift control unit 17 controls shifting of the gear of the transmission 2 so as to downshift to the target gear without inhibiting downshift when the calculated rotation speed is lower than a predetermined value. In this way, although the rotation speed of the engine 1 is too low in the current travel interval, the vehicle control device 10 can suppress the feeling of discomfort given to the driver by not changing the shift position.

[ Exception 2 for suppressing downshift ]

The shift control portion 17 calculates the lowest speed of the vehicle V in the current travel section from the speed of the vehicle V and the stall amount of the vehicle V in the current travel section. Then, when the minimum speed is lower than a slower speed, which is higher than the minimum speed at which the vehicle V can travel in the forward travel section, among the speeds of the vehicle V corresponding to the current gear, the shift control unit 17 controls shifting of the gear so as to downshift to the target gear without inhibiting the downshift.

Next, an example will be described in which the shift control unit 17 controls not to suppress a downshift based on the minimum speed and the retard speed of the vehicle V in the current travel section. First, the shift control portion 17 calculates the lowest speed of the vehicle V in the current running section. Here, the lowest speed of the vehicle V is a speed when entering the forward travel section. Therefore, the shift control unit 17 sets the calculated speed of the vehicle V when entering the preceding travel section as the lowest speed of the vehicle V in the current travel section.

Further, among the speeds of the vehicle V corresponding to the current gear, the shift control portion 17 determines the lowest speed at which the vehicle V can travel in the forward travel section. Specifically, the shift control unit 17 determines the lowest speed of the vehicle V that can travel in the current shift position, based on the running performance characteristic indicating the relationship between the speed and the driving force of the vehicle V corresponding to the current shift position, which is indicated by the driving force characteristic information of the vehicle V, and the calculated running resistance in the forward running section. Here, the lowest speed is a lower speed among the speeds at which the driving force of the current gear and the running resistance of the preceding running section are equal.

The shift control unit 17 calculates a delay speed that is higher than the minimum speed of the vehicle V that can travel in the current gear by a predetermined speed. Here, the predetermined speed is, for example, a speed 5% higher than the minimum speed. When the minimum speed of the vehicle V in the current travel section is lower than the retard speed, the shift control unit 17 controls shifting of the shift range so as to downshift to the target shift range without inhibiting the downshift. In this way, the vehicle control device 10 can prevent the vehicle from traveling in the current gear position because the speed is lower than expected in the forward traveling zone.

[ Exception 3 to inhibit downshifting ]

In the case of running in a state where a deep step switch allowing deep stepping is on, the shift control portion 17 controls shifting of the shift range of the transmission 2 so as to downshift from the current shift range to the target shift range without inhibiting the downshift. Further, when the vehicle V is running in the auto cruise mode, the shift control unit 17 controls the shift of the shift range of the transmission 2 so as to downshift from the current shift range to the target shift range without inhibiting the downshift when the accelerator opening degree detected by the accelerator opening degree sensor 6 is equal to or greater than a predetermined opening degree. Here, the predetermined opening degree is, for example, an opening degree of 80% of the maximum opening degree. In this way, the vehicle control device 10 can perform the downshift with priority given to the intention of the driver of the vehicle V depressing the accelerator and accelerating the vehicle V.

Further, the shift control unit 17 may control the shift of the shift range of the transmission 2 so as to downshift from the current shift range to the target shift range when it is detected that the accelerator opening degree detected by the accelerator opening degree sensor 6 changes from an opening degree smaller than the first opening degree to an opening degree larger than the second opening degree within a predetermined time (for example, 3 seconds). Here, the first opening degree is, for example, an opening degree of 10% of the maximum opening degree, and the second opening degree is, for example, an opening degree of 80% of the maximum opening degree.

[ Exception to inhibit downshift 4]

Further, when the front gear selected by the front gear selection unit 16 is smaller than the current gear, the shift control unit 17 controls shifting of the gear of the transmission 2 so as to downshift from the current gear to the target gear without inhibiting the downshift. Here, in the case where the running mode of the vehicle V is the power mode, the front range selection portion 16 tends to select a range lower than that in the eco mode. Therefore, when the running mode of the vehicle V is the power mode, the frequency of the forward range selected by the forward range selecting unit 16 being lower than the current range by 1 st or more increases, and the number of times of not performing downshift suppression by the shift control unit 17 increases, as compared with the economy mode. In this way, when the running mode of the vehicle V is the power mode, the vehicle control device 10 can improve the running performance as compared with the economy mode.

[ Process flow for early downshift control ]

Next, a flow of the shift control process according to the embodiment will be described. First, a flow of a process of shift control based on the forward range will be described. Fig. 6 is a flowchart for explaining the flow of processing relating to early downshift control executed by the vehicle control device 10 according to the embodiment. Note that the processing of the present flowchart is started in correspondence with the start of the travel of the vehicle V. The process of the flowchart is continued while the vehicle V is traveling.

The front shift position selection unit 16 selects a front shift position (S2). The shift control unit 17 calculates the stall amount of the vehicle V in the forward travel section (S4).

The shift control unit 17 determines whether or not the forward shift position selected by the forward shift position selection unit 16 is lower than the current shift position by 2 or more (S6). If the speed is not higher than 1 st (no in S6), the shift control unit 17 proceeds to S2.

When the low gear is not less than 2 (yes at S6), the shift control unit 17 determines whether or not the stall amount of the vehicle V in the forward traveling zone is less than a predetermined amount (S8). If the amount is less than the predetermined amount (yes at S8), shift control unit 17 shifts the process to S2.

If the vehicle speed is equal to or higher than the predetermined amount (no in S8), shift control unit 17 determines whether or not vehicle V is located at the start position of the forward travel section (S10). If the vehicle V is not located at the start position of the forward travel section (no at S10), the shift control unit 17 proceeds to S2.

When the vehicle V is located at the start position of the forward running section (yes at S10), the shift control unit 17 shifts down from the current shift position to the forward shift position (S12).

[ Process flow for suppressing downshift control ]

Next, a flow of processing of the downshift control according to the embodiment will be described. Fig. 7 is a flowchart for explaining the flow of processing relating to the downshift control executed by the vehicle control device 10 according to the embodiment. The processing in this flowchart starts when the current gear selection section 13 newly selects a target gear that is a lower gear than the current gear.

The shift control unit 17 determines whether or not the forward shift position selected by the forward shift position selecting unit 16 is equal to or greater than the current shift position (S22). If the forward shift position is equal to or higher than the current shift position (yes at S22), shift control unit 17 shifts the process to S26. If the forward gear is smaller than the current gear (no at S22), the shift control unit 17 shifts the process to S24 to control shifting of the gear of the transmission 2 so as to downshift from the current gear to the target gear.

The shift control portion 17 calculates the stall amount of the vehicle V in the current running section (S26). The shift control unit 17 determines whether or not the calculated stall amount is equal to or less than a predetermined threshold value (S28). If the current gear is higher than the predetermined threshold value (no in S28), the shift control unit 17 controls the shift of the shift position of the transmission 2 so as to downshift from the current shift position to the target shift position (S24). If the value is equal to or less than the predetermined threshold value (yes at S28), the shift control unit 17 proceeds to S30.

The shift control portion 17 calculates the lowest rotation speed of the engine 1 of the vehicle V in the current running section (S30). The shift control unit 17 determines whether or not the calculated minimum rotation speed of the engine 1 is less than a predetermined value (S32). If the current gear is smaller than the predetermined value (yes at S32), the shift control unit 17 shifts the process to S24 to control the shift of the gear of the transmission 2 so as to downshift from the current gear to the target gear. If the value is equal to or greater than the predetermined value (no in S32), the shift control unit 17 proceeds to S34.

The shift control unit 17 calculates the lowest speed of the vehicle V in the current running section (S34). The shift control unit 17 determines whether or not the minimum speed of the vehicle V in the current running section is equal to or less than the retard vehicle speed (S36). When the minimum speed of the vehicle V in the current running section is equal to or lower than the suspended vehicle speed (yes at S36), the shift control unit 17 shifts the process to S24. That is, the shift control unit 17 controls the shift of the shift range of the transmission 2 so as to downshift from the current shift range to the target shift range without performing downshift suppression.

When the minimum speed of the vehicle V in the current running section is greater than the retard vehicle speed (no at S36), the shift control unit 17 determines whether or not the deep step switch is on (S38). When the deep step switch is on (yes at S38), the shift control unit 17 shifts the process to S24. That is, the shift control unit 17 controls shifting of the shift position of the transmission 2 so as to perform downshift. When the deep step switch is off (no in S38), the shift control unit 17 shifts the process to S40.

The shift control unit 17 determines whether the vehicle V is in the auto cruise mode and the accelerator opening degree detected by the accelerator opening degree sensor 6 is larger than a predetermined opening degree (S40). When the vehicle is in the auto cruise mode and the accelerator opening is larger than the predetermined opening (yes at S40), the shift control unit 17 shifts the process to S24. That is, the shift control unit 17 controls shifting of the shift range of the transmission 2 so as to downshift from the current shift range to the target shift range without performing downshift suppression.

When the vehicle V is not in the auto cruise mode, or when the accelerator opening is equal to or smaller than the predetermined opening (no at S40), the shift control unit 17 ends the process of this flow. That is, the shift control unit 17 controls shifting of the shift range of the transmission 2 so as to suppress downshift.

[ Effect of the present embodiment ]

As described above, the vehicle control device 10 according to the present embodiment controls the shift of the shift range so as to downshift from the current shift range to the target shift range without inhibiting the downshift even when the state of the vehicle V satisfies the predetermined condition while the downshift is inhibited. In this way, the vehicle control device 10 can cause the vehicle V to travel in a state where the speed of the vehicle V can be quickly recovered. Further, since the vehicle control device 10 suppresses the downshift when the predetermined condition is not satisfied, the number of shifts can be reduced, and fuel efficiency can be improved.

In addition, the front range selection unit 16 of the vehicle control device 10 selects the range in different manners in the economy mode and the power mode, and therefore can select the range corresponding to the economy mode and the power mode. Thus, in the power mode, the vehicle V has a front gear relatively in the economy mode, and the situation where the low gear is selected is increased compared to the case where the vehicle V travels in the economy mode, and therefore, the frequency of execution of the downshift is suppressed from decreasing. As a result, in the vehicle V, the number of times the condition for suppressing the downshift is satisfied is reduced, and the downshift is performed. This enables the vehicle V to travel with importance placed on the traveling performance. In addition, since the vehicle V has an increased situation in which a high gear is selected in the economy mode, the frequency of performing downshift suppression increases, and fuel efficiency can be emphasized during running.

The present disclosure has been described above with reference to the embodiments, but the technical scope of the present disclosure is not limited to the scope described in the above embodiments, and various modifications and changes can be made within the scope of the present disclosure. For example, the specific embodiments of the separation and integration device are not limited to the above-described embodiments, and all or a part of the devices may be configured by functionally or physically separating and integrating the devices in arbitrary units. In addition, a new embodiment which is created by arbitrary combination of the plurality of embodiments is also included in the embodiments of the present disclosure. The effects of the new embodiment produced by the combination have the effects of the original embodiment at the same time.

The present application is based on the japanese patent application filed on 12/5/2017 (japanese application 2017-095970), the content of which is hereby incorporated by reference.

[ Industrial Applicability ]

The vehicle control device of the present disclosure is useful in that a shift position suitable for a running mode of a vehicle can be selected.

[ description of reference numerals ]

1 Engine

2 speed variator

3 GPS sensor

4 weight sensor

5 speed sensor

6 accelerator opening sensor

10 vehicle control device

11 storage section

12 control part

13 current gear selection part

14 road gradient acquisition unit

15 travel section determining unit

16 forward gear selecting part

17 Shift control section

V vehicle