JP2024052279A - Vehicle control device - Google Patents

Abstract

[Problem] To provide a vehicle control device that can suppress rattle shock and suppress deterioration of response. [Solution] Rattle torque is calculated based on the current input torque of the power transmission device, the current detection value by a rotation sensor, and setting the output torque of the power transmission device at the time of rattle equal to the current output torque of the power transmission device. The rattle torque can be calculated with high accuracy taking into account the actual usage environment by the above calculation method that uses current values other than the output torque that reflect the usage environment such as running resistance and gradient, without using the output torque of the power transmission device that is determined by the running resistance and gradient. Therefore, rattle shock can be suppressed and deterioration of response can be suppressed. [Selected Figure] Figure 2

Description

The present invention relates to a control device for a vehicle equipped with a power transmission device that transmits power from a power source to drive wheels.

A vehicle control device including a power source, a power transmission device that transmits power from the power source to a driving wheel, and a rotation sensor that detects a value corresponding to the rotation speed of a rotating member that constitutes the power transmission device is well known. For example, a control device for an internal combustion engine described in Patent Document 1 is one such device. Patent Document 1 discloses that in the engine torque damping process accompanying accelerator release, a first damping period, a second damping period, and a third damping period are set, and the damping rate of the second damping period is made smaller than those of the first damping period and the third damping period. The second damping period corresponds to a drive/driven switching region including a rattle time point at which the power transmission state of the power transmission device is switched from a drive state to a driven state. Since the direction of rattle reduction in the power transmission device is reversed with the so-called tip-out at which the power transmission state of the power transmission device is switched from a drive state to a driven state, there is a risk of rattle shock occurring, which is a shock caused by tooth strike. In the technology of Patent Document 1, the rattle shock is suppressed by making the damping rate of the second damping period relatively small.

JP 2014-47667 A

The driving/driven switching region is determined in advance based on the rattle torque, which is the torque at the time of rattle calculated from standard conditions such as flat roads and vehicle specifications. However, the actual use environment of the vehicle may differ from the standard conditions due to uphill roads or packed snow roads, or the vehicle specifications may change due to tire changes, etc., and the actual rattle time may not fall within the predetermined driving/driven switching region. In that case, the rattle shock may not be appropriately suppressed. In response to this, for example, as described in Patent Document 1, it is possible to reduce the damping rate in the regions before and after the driving/driven switching region depending on the operating state of the air conditioner driven by the engine output and the warm-up state of the engine. Alternatively, it is possible to increase the torque width of the driving/driven switching region. However, the above-mentioned measures may lengthen the overall period for changing the torque, which may lead to a response delay, i.e., a deterioration in response. There is room for improvement in improving the drivability of the vehicle in various environments. Furthermore, a similar problem may occur when the power transmission state of the power transmission device is switched from a driven state to a driving state (so-called tip-in) when the accelerator is turned on.

The present invention was made against the background of the above circumstances, and its purpose is to provide a vehicle control device that can suppress rattle shock and reduce deterioration of response.

The gist of the first invention is that (a) a control device for a vehicle equipped with a power source, a power transmission device that transmits power from the power source to drive wheels, and a rotation sensor that detects a value corresponding to the rotation speed of a rotating member that constitutes the power transmission device, (b) includes a torque calculation unit that calculates a rattle torque, which is the input side torque of the power transmission device at the time of rattle, based on the current input side torque of the power transmission device, the current detection value by the rotation sensor, and setting the output side torque of the power transmission device at the time of rattle when the power transmission state of the power transmission device is switched between a driving state and a driven state to the same value as the current output side torque of the power transmission device.

According to the first invention, the rattle torque is calculated based on the current input torque of the power transmission device, the current detection value by the rotation sensor, and setting the output torque of the power transmission device at the time of rattle to the same value as the current output torque of the power transmission device. In other words, by taking advantage of the fact that the current value of the output torque of the power transmission device and the value at the time of rattle are treated as the same value, the rattle torque is calculated using the current values of the input torque of the power transmission device and the detection value by the rotation sensor. The rattle torque can be calculated accurately by taking into account the actual usage environment by the above calculation method using the current value other than the output torque that reflects the usage environment such as the running resistance and the gradient, without using the output torque of the power transmission device determined by the running resistance and the gradient. This makes it possible to accurately predict the area where rattle occurs, and even if the torque area where rattle occurs is made small, the rattle shock can be appropriately suppressed. Also, in the torque area where rattle does not occur, the input torque of the power transmission device can be changed quickly. Therefore, the rattle shock can be suppressed and the deterioration of the response can be suppressed.

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. 4 is a flowchart illustrating a main part of the control operation of the electronic control device, and is a flowchart illustrating the control operation for suppressing rattle shock and suppressing deterioration of response. 3 is a diagram showing an example of a time chart when the control operation shown in the flowchart of FIG. 2 is executed. FIG. FIG. 2 is a diagram for explaining a schematic configuration of a vehicle to which the present invention is applied, which is an embodiment different from the vehicle shown in FIG. 1 . 3 is a flowchart illustrating the main control operations of the electronic control device, and is a flowchart illustrating the control operations for suppressing rattle shocks and suppressing deterioration of response, which is an embodiment different from the flowchart of FIG. 2. FIG. 5 is a diagram for explaining the schematic configuration of a vehicle to which the present invention is applied, which is an embodiment different from the vehicles in FIG. 1 and FIG.

In an embodiment of the present invention, the rotational speed of a rotating member constituting the power transmission device corresponds to the angular speed of the rotating member. The amount of change in the rotational speed of the rotating member is the amount of change in a control cycle that is repeatedly executed, for example, the rate of change in the rotational speed of the rotating member. The rate of change in the rotational speed of the rotating member is the time rate of change of the rotational speed of the rotating member, i.e., the time derivative, and corresponds to the angular acceleration of the rotating member. The rotational speed is represented as rotational speed ω, and the rate of change in the rotational speed is represented as rotational change amount dω/dt. In formulas, the rotational change amount dω/dt may be represented by a dot at ω.

The gear ratio (also called the gear ratio) of the devices that make up the power transmission device, such as the differential device and the transmission, is "input rotation speed/output rotation speed."

The following describes in detail an embodiment of the present invention with reference to the drawings.

Figure 1 is a diagram illustrating the general configuration of a vehicle 10 to which the present invention is applied, as well as a diagram illustrating the main parts of the control functions and control system for various controls in the vehicle 10. In Figure 1, the vehicle 10 is equipped with an engine 12 as a power source, drive wheels 14, and a power transmission device 16 provided in the power transmission path between the engine 12 and the drive wheels 14.

The engine 12 is a known internal combustion engine. The engine torque Te of the engine 12 is controlled by an engine control device 50 provided in the vehicle 10, which is controlled by an electronic control device 80 described below.

The power transmission device 16 includes a torque converter 20, an automatic transmission 22, and the like, in a case 18 that is a non-rotating member. The torque converter 20 is connected to the engine 12. The automatic transmission 22 is connected to the torque converter 20 and is interposed in the power transmission path between the torque converter 20 and the drive wheels 14. The power transmission device 16 also includes a propeller shaft 26 connected to a transmission output shaft 24 that is an output rotating member of the automatic transmission 22, a differential gear 28 connected to the propeller shaft 26, and a pair of drive shafts 30 connected to the differential gear 28. The differential gear 28 is a differential device that distributes power from the engine 12 to the left and right wheels of the drive wheels 14. The automatic transmission 22 is a transmission provided in the power transmission path between the engine 12 and the differential gear 28. The power transmission device 16 also includes an engine connecting shaft 32 that connects the engine 12 and the torque converter 20.

The torque converter 20 includes a pump impeller 20a connected to an engine connecting shaft 32, and a turbine impeller 20b connected to a transmission input shaft 34, which is an input rotating member of the automatic transmission 22. The torque converter 20 includes a known lock-up clutch 36.

The automatic transmission 22 is, for example, a known planetary gear type automatic transmission. The automatic transmission 22 is switched between a plurality of gear stages (also called gear stages) with different gear ratios γat (=AT input rotation speed ωati/AT output rotation speed ωato) that are formed according to the driver's accelerator operation, the vehicle speed V, etc. by an electronic control device 80 described later. The AT input rotation speed ωati is the rotation speed of the transmission input shaft 34, and is the input rotation speed of the automatic transmission 22. The AT output rotation speed ωato is the rotation speed of the transmission output shaft 24, and is the output rotation speed of the automatic transmission 22.

The vehicle 10 is equipped with a mechanical oil pump 38 connected to a pump impeller 20a that supplies hydraulic oil OIL to a hydraulic control circuit 52 provided in the vehicle 10. The vehicle 10 is also equipped with an alternator 54 (see "ALT" in the figure) and an air conditioner compressor 56 (see "A/C" in the figure) that are connected to the engine 12 via a belt 40 or the like.

The vehicle 10 is equipped with an electronic control device 80 that includes a control device for the vehicle 10. The electronic control device 80 includes, for example, a CPU, RAM, ROM, an input/output interface, etc.

The electronic control device 80 is supplied with various signals (e.g., engine speed ωe, which is the rotational speed of the engine 12; AT input rotational speed ωati; AT output rotational speed ωato, which corresponds to the vehicle speed V; driving wheel speeds ωrl, ωrr, which are the rotational speeds of the left and right driving wheels 14; driven wheel speeds ωsl, ωsr, which are the rotational speeds of the left and right driven wheels (not shown); accelerator opening θacc; throttle valve opening θth, etc.) based on detection values from various sensors (e.g., engine speed sensor 60, AT input rotational speed sensor 62, AT output rotational speed sensor 64, wheel speed sensor 66, accelerator opening sensor 68, throttle valve opening sensor 70, etc.) provided in the vehicle 10.

The electronic control device 80 outputs various command signals (e.g., engine control command signal Se, hydraulic control command signal Sat, etc.) to each device (e.g., engine control device 50, hydraulic control circuit 52, etc.) provided in the vehicle 10.

However, when passing through the driving/driven switching region due to tip-in or tip-out, rattle shock may occur. The driving/driven switching region is a torque region where rattle occurs, i.e., a rattle region. For this reason, when passing through the rattle region, the electronic control device 80, for example, makes the change in engine torque Te gentle to suppress the rattle shock. If the change in engine torque Te is made gentle, the response may deteriorate, leading to deterioration in drivability and fuel economy. It is desirable to make the rattle region as small as possible to shorten the period during which the change in engine torque Te is gentle, and to change the engine torque Te quickly before and after the rattle region. On the other hand, the rattle region may change depending on the actual usage environment of the vehicle 10. It is desirable to accurately predict the rattle region according to the actual usage environment of the vehicle 10.

The electronic control device 80 is equipped with a torque calculation means, i.e., a torque calculation unit 82, in order to accurately predict the rattle region. The torque calculation unit 82 calculates the rattle torque Tgt using the input side torque of the power transmission device 16, which is the generated torque input to the power transmission device 16, and a rotation sensor that detects a value corresponding to the rotation speed of the rotating members that make up the power transmission device 16. The rattle torque Tgt is the input side torque of the power transmission device 16 at the rattle point when the power transmission state of the power transmission device 16 is switched between a driving state and a driven state.

The input torque of the power transmission device 16 is the engine torque Te, the input torque of the differential gear 28 based on the engine torque Te, i.e., the differential input torque Tin, etc.

The rotating members constituting the power transmission device 16 are the engine connecting shaft 32, the transmission input shaft 34, the transmission output shaft 24, the drive shaft 30, etc. The engine rotation speed sensor 60 is a rotation sensor that detects a value corresponding to the rotation speed of the engine connecting shaft 32. The AT input rotation speed sensor 62 is a rotation sensor that detects a value corresponding to the rotation speed of the transmission input shaft 34. The AT output rotation speed sensor 64 is a rotation sensor that detects a value corresponding to the rotation speed of the transmission output shaft 24. The wheel speed sensor 66 is a rotation sensor that detects a value corresponding to the rotation speed of the drive shaft 30. The AT output rotation speed ωato, which is the detection value of the AT output rotation speed sensor 64, corresponds to the input side rotation speed of the differential gear 28, i.e., the differential input side rotation speed ωin. The driving wheel speeds ωrl, ωrr, which are detection values of the wheel speed sensor 66, correspond to the output side rotation speed of the differential gear 28, i.e., the differential output side rotation speed ωout. The differential output rotation speed ωout is, for example, the average value of the drive wheel speeds ωrl and ωrr.

As shown in FIG. 1, the entire drive system from the engine 12 to the drive wheels 14 is expressed in equivalent form before and after the differential gear 28. In FIG. 1, "Tin" is the differential input torque, and "Tout" is the output torque of the differential gear 28, i.e., the differential output torque. The "ωin dot" is the amount of change in the differential input rotation speed ωin, i.e., the differential input rotation change amount dωin/dt, and the "ωout dot" is the amount of change in the differential output rotation speed ωout, i.e., the differential output rotation change amount dωout/dt. "Iin" is the predetermined total equivalent inertial weight from the engine 12 to the input side of the differential gear 28, i.e., the input side total equivalent inertial weight, and "Iout" is the predetermined total equivalent inertial weight from the output side of the differential gear 28 to the drive wheels 14, i.e., the output side total equivalent inertial weight.

The equation of motion of the entire drive system, assuming that the present is when there is torque transmission across the differential gear 28, that is, when there is a positive or negative drive torque Tr and no rattle, can be expressed by the following equation (1). In the following equation (1), "Tinnow" is the current differential input torque Tin, i.e., the current differential input torque, and "Toutnow" is the current differential output torque Tout, i.e., the current differential output torque. The differential output torque Tout corresponds to the output torque of the power transmission device 16. "dωinnow/dt" is the current differential input rotation change dωin/dt, i.e., the current differential input rotation change. "ρ" is the predetermined gear ratio of the differential gear 28, i.e., the differential gear ratio. The current differential output rotation change dωout/dt, i.e., the current differential output rotation change dωoutnow/dt, is expressed using the differential gear ratio ρ and the current differential input rotation change dωinnow/dt.

T innow + (1/ρ) × T outnow
= (Iin + (1/ ^ρ2 ) × Iout) × dωinnow/dt ... (1)

The equation of motion when there is no torque transmission between the front and rear of the differential gear 28, i.e., at the time of rattle, can be expressed by the following equations (2) and (3). In the following equations (2) and (3), "Ting" is the differential input torque Tin at the time of rattle, i.e., the differential rattle torque, and "Toutg" is the differential output torque Tout at the time of rattle, i.e., the rattle differential output torque. The differential rattle torque Ting corresponds to the rattle torque Tgt that is to be determined. "dωing/dt" is the differential input rotation change dωin/dt at the time of rattle, i.e., the rattle differential input rotation change.

Ting = Iin × dωing/dt (2)
Toutg=Iout×dωing/dt×(1/ρ) (3)

By taking advantage of the fact that the time between when tip-in or tip-out is determined and when rattle actually occurs is sufficiently short, it is possible to approximate Toutnow = Toutg. As a result, rearranging the above equations (1), (2), and (3) for the differential rattle torque Ting gives the following equation (4).

Ting = Iin × ρ ² / Iout
× ((Iin + (1/ρ ² ) × Iout) × dωinnow/dt - Tinnow) ... (4)

The current differential output torque Toutnow and the rattle differential output torque Toutg are each values that are determined by the usage environment of the vehicle 10 at that time, such as the running resistance and gradient. However, when the current differential output torque Toutnow is calculated using fixed values for the running resistance and gradient, the actual usage environment of the vehicle 10 cannot be reflected. In contrast, by approximating Toutnow = Toutg, it is possible to replace the current differential output torque Toutnow with a calculation method that uses the current differential input torque Tinnow, the current differential input rotation change amount dωinnow/dt, the input side total equivalent inertia weight Iin, and the output side total equivalent inertia weight Iout, which reflect the actual usage environment of the vehicle 10.

The torque calculation unit 82 calculates the differential rattle torque Ting based on the current differential input torque Tinnow, the current differential input rotation change amount dωinnow/dt, the input side total equivalent inertia weight Iin, the output side total equivalent inertia weight Iout, the differential gear ratio ρ, and setting the rattle differential output torque Toutg to the same value as the current differential output torque Toutnow.

The torque calculation unit 82 calculates the current differential input torque Tinnow using the engine torque Te, the gear ratio γat of the automatic transmission 22, and the like, for example, as shown in the following equation (5). The torque calculation unit 82 calculates an estimate of the engine torque Te at the throttle valve opening θth and the engine rotation speed ωe, for example, using a predetermined engine torque map. In the following equation (5), "t" is the torque ratio of the torque converter 20. The torque ratio t is a function of the speed ratio e (= turbine rotation speed / pump rotation speed) of the torque converter 20. The torque calculation unit 82 calculates the torque ratio t by applying the actual speed ratio e to, for example, a predetermined relationship between the speed ratio e and the torque ratio t. The torque calculation unit 82 calculates the actual speed ratio e (= ωati / ωe) based on the AT input rotation speed ωati, which is the same as the turbine rotation speed, which is the rotation speed of the turbine impeller 20b, and the engine rotation speed ωe, which is the same as the pump rotation speed, which is the rotation speed of the pump impeller 20a. The torque calculation unit 82 calculates the current differential input torque Tinnow by substituting the estimated value of the engine torque Te, the torque ratio t, and the gear ratio γat for "Te" in the following equation (5). Note that the torque transmission efficiency in the power transmission path from the engine 12 to the differential gear 28 may also be taken into account in the following equation (5).

Tinnow = Te x t x γat ... (5)

The torque calculation unit 82 calculates the current differential input side rotation change amount dωinnow/dt, for example, using the AT output rotation speed ωato corresponding to the differential input side rotation speed ωin. Alternatively, the torque calculation unit 82 may calculate the current differential input side rotation change amount dωinnow/dt, for example, using the drive wheel speeds ωrl and ωrr corresponding to the differential output side rotation speed ωout converted to the input side of the differential gear 28 by the differential gear ratio ρ. Therefore, the above formula (4) may be an equation in which the current differential input side rotation change amount dωinnow/dt is replaced by the current differential output side rotation change amount dωoutnow/dt. Alternatively, the torque calculation unit 82 may calculate the current differential input side rotation change amount dωinnow/dt, for example, using the value converted to the input side of the differential gear 28 by the gear ratio γat, etc. Alternatively, the torque calculation unit 82 may calculate the current differential input rotation change amount dωinnow/dt using the detection value of the rotation sensor with the highest detection accuracy. Alternatively, the detection value of the rotation sensor may be smoothed by a low-pass filter.

The speed ratio between the engine rotation speed ωe and the differential input side rotation speed ωin differs depending on the gear ratio γat of the automatic transmission 22. Therefore, the input side total equivalent inertia weight Iin differs depending on the gear ratio γat. The torque calculation unit 82 calculates the input side total equivalent inertia weight Iin based on the actual gear ratio γat, for example, using the input side total equivalent inertia weight Iin predetermined for each gear ratio γat of the automatic transmission 22. In other words, the torque calculation unit 82 sets the input side total equivalent inertia weight Iin corresponding to the gear ratio γat, which is predetermined, as the input side total equivalent inertia weight Iin used to calculate the rattle torque Tgt.

The torque calculation unit 82 calculates the output side total equivalent inertia weight Iout (=vehicle weight x tire dynamic load radius ² ) using, for example, the vehicle weight and the tire dynamic load radius of the drive wheels 14. For example, since the vehicle weight and the tire dynamic load radius of the drive wheels 14 are each set to a predetermined value, the torque calculation unit 82 sets the output side total equivalent inertia weight Iout set to a predetermined value as the output side total equivalent inertia weight Iout used to calculate the rattle torque Tgt. Strictly speaking, the output side total equivalent inertia weight Iout includes the inertia of 30 minutes of the drive shaft, etc., but since the 30 minutes of the drive shaft, etc. is sufficiently small compared to the vehicle weight, it is excluded when calculating the output side total equivalent inertia weight Iout.

The torque calculation unit 82 calculates the differential rattle torque Ting using the above formula (4), and then calculates the engine rattle torque Teg, which is the engine torque Te during rattle, using the following formula (6). The engine rattle torque Teg also corresponds to the rattle torque Tgt to be determined. Note that in the following formula (6), the torque transmission efficiency in the power transmission path from the engine 12 to the differential gear 28 may be taken into account.

Teg = Ting / (t x γat) ... (6)

As described above, the torque calculation unit 82 calculates the rattle torque Tgt based on the current input torque of the power transmission device 16 (engine torque Te, differential input torque Tin, etc.), the current detection value by the rotation sensor (AT output rotation speed ωato, drive wheel speeds ωrl, ωrr, etc.), and setting the output torque of the power transmission device 16 at the time of rattle (rattle differential output torque Toutg) to the same value as the current output torque of the power transmission device 16 (current differential output torque Toutnow).

The torque calculation unit 82 may constantly calculate the rattle torque Tgt. When the electronic control unit 80 determines that a tip-in or tip-out has occurred, the torque calculation unit 82 sets the rattle region to a torque range that includes the rattle torque Tgt calculated by the torque calculation unit 82, for example, the engine rattle torque Teg, at approximately the center. The electronic control unit 80 changes the engine torque Te more gradually in the rattle region than in the regions before and after the rattle region. Alternatively, the torque calculation unit 82 may not constantly calculate the rattle torque Tgt, but may calculate the rattle torque Tgt when the electronic control unit 80 determines that a tip-in or tip-out has occurred. For example, the torque calculation unit 82 calculates the rattle torque Tgt at a predetermined time from the start of a transition period in which the power transmission state of the power transmission device 16 is switched from one of the driving state and the driven state to the other, until before the rattle time.

Figure 2 is a flowchart that explains the main control operations of the electronic control device 80, and is a flowchart that explains the control operations for suppressing rattle shocks and suppressing deterioration of response, and is executed repeatedly, for example. Figure 3 is a diagram showing an example of a time chart when the control operations shown in the flowchart of Figure 2 are executed.

2, each step of the flowchart corresponds to the function of the torque calculation unit 82. In step (hereinafter, step is omitted) S10, the drive wheel speeds ωrl and ωrr are obtained. Also, an estimate of the current engine torque Te is obtained. Also, the current gear ratio γat of the automatic transmission 22 is obtained. Next, in S20, the input side total equivalent inertia weight Iin and the output side total equivalent inertia weight Iout are calculated. Also, the current differential input side torque Tinnow is calculated using the engine torque Te, the gear ratio γat of the automatic transmission 22, etc. (see the previous formula (5)). Next, in S30, the current differential input side rotation change amount dωinnow/dt is calculated using the value converted from the drive wheel speeds ωrl and ωrr to the input side of the differential gear 28 by the differential gear ratio ρ. Next, in S40, the differential rattle torque Ting is calculated using the input side total equivalent inertia weight Iin, the output side total equivalent inertia weight Iout, the current differential input side torque Tinnow, the current differential input side rotation change amount dωinnow/dt, and the differential gear ratio ρ (see formula (4) above).

Figure 3 shows an example of a case where a tip-out has occurred. In Figure 3, time t1 indicates the time when it is determined that a tip-out has occurred due to release of the accelerator. Time t2 indicates the time when the rattle region is determined based on the calculated rattle torque Tgt. In this rattle region, shock suppression control is implemented to suppress rattle shock (see time t3-t5). Time t4 indicates the time when rattle is predicted to occur. In this shock suppression control, the generated torque is changed more gradually than before and after the rattle region.

As described above, according to this embodiment, the rattle torque Tgt is calculated based on the current input torque of the power transmission device 16, the current detection value by the rotation sensor, and the output torque of the power transmission device 16 at the time of rattle being set to the same value as the current output torque of the power transmission device 16. In other words, by taking advantage of the fact that the current value of the output torque of the power transmission device 16 and the value at the time of rattle are treated as the same value, the rattle torque Tgt is calculated using the current values of the input torque of the power transmission device 16 and the detection value by the rotation sensor. The rattle torque Tgt can be calculated accurately by taking into account the actual usage environment using the above calculation method using the current values other than the output torque that reflect the usage environment such as the running resistance and the gradient, without using the output torque of the power transmission device 16 determined by the running resistance and the gradient. Therefore, it is possible to suppress the rattle shock and the deterioration of the response.

In addition, according to this embodiment, the rattle torque Tgt is calculated at a predetermined time from the start of a transition period in which the power transmission state of the power transmission device 16 is switched from one of the driving state and the driven state to the other, until the rattle point. This allows the rattle region to be determined with high accuracy.

In addition, according to this embodiment, the differential rattle torque Ting is calculated as the rattle torque Tgt based on the current differential input torque Tinnow, the current differential input rotation change amount dωinnow/dt or the current differential output rotation change amount dωoutnow/dt, the predetermined input total equivalent inertia weight Iin, the predetermined output total equivalent inertia weight Iout, the differential gear ratio ρ, and setting the rattle differential output torque Toutg to the same value as the current differential output torque Toutnow. This allows the rattle region to be determined with high accuracy.

In addition, according to this embodiment, the input side total equivalent inertia weight Iin used to calculate the rattle torque Tgt is set to a predetermined input side total equivalent inertia weight Iin corresponding to the gear ratio γat. This allows the rattle region to be determined with even greater accuracy.

Next, other embodiments of the present invention will be described. In the following description, parts common to the embodiments will be given the same reference numerals and will not be described.

Figure 4 is a diagram illustrating the general configuration of a vehicle 100 to which the present invention is applied. The vehicle 100 is a different embodiment from the vehicle 10 of the first embodiment described above.

In FIG. 4, the vehicle 100 is a hybrid vehicle equipped with an engine 102 and an electric motor 104 as a power source. The vehicle 100 also has driving wheels 106 and a power transmission device 108 provided in a power transmission path between the engine 102 and the driving wheels 106.

The power transmission device 108 includes a clutch 110, an automatic transmission 112 including a torque converter, and the like. The clutch 110 is an on-off clutch provided between the engine 102 and the electric motor 104 in the power transmission path between the engine 102 and the drive wheels 106. The automatic transmission 112 is connected to the engine 102 via the clutch 110, and is connected to the electric motor 104 without the clutch 110. The power transmission device 108 also includes a propeller shaft 114 connected to the output rotating member of the automatic transmission 112, a differential gear 116 connected to the propeller shaft 114, a pair of drive shafts 118 connected to the differential gear 116, and the like. The automatic transmission 112 is a transmission provided in the power transmission path between the engine 102 and the differential gear 116. The differential gear 116 is a differential device that distributes power from the engine 102 and the electric motor 104 to the left and right wheels of the drive wheels 106.

The engine torque Te of the engine 102 is controlled by an electronic control device 120 provided in the vehicle 100. The electric motor 104 is a rotating electric machine, and the motor torque Tm, which is the torque of the electric motor 104, is controlled by the electronic control device 120. The automatic transmission 112 is a known planetary gear type automatic transmission in which the gear stages formed by the electronic control device 120 are switched. The electronic control device 120 is a control device for the vehicle 100.

The clutch 110 is a hydraulic friction engagement device that is composed of, for example, a multi-plate or single-plate clutch. The clutch 110 is switched between operating states, i.e., control states, such as an engaged state, a slip state, and a released state, by the electronic control device 120. In the vehicle 100, as shown in FIG. 4(a), when the clutch 110 is in an engaged state, the engine 102 and the automatic transmission 112 are connected so as to be capable of transmitting power. On the other hand, as shown in FIG. 4(b), when the clutch 110 is in a released state, the power transmission between the engine 102 and the automatic transmission 112 is interrupted. Therefore, when the clutch 110 is in a released state, the power from the electric motor 104 can be transmitted to the drive wheels 106, but the power from the engine 102 is not transmitted to the drive wheels 106. The clutch 110 is a clutch that can interrupt the power transmission from the engine 102 to the differential gear 116.

The calculation formula for the differential rattle torque Ting shown in the above formula (4) can also be applied to the vehicle 100. However, since the engine 102 can be separated from the power transmission system by the clutch 110 in the vehicle 100, it is necessary to take into account the input side total equivalent inertia weight Iin and the current differential input side torque Tinnow according to the control state of the clutch 110.

The input side total equivalent inertia weight Iin excludes the inertia (= equivalent inertia weight) of the engine 102, which is cut off from the power transmission to the differential gear 116 when the clutch 110 is in the disengaged state. The following formula (7) is the input side total equivalent inertia weight Iin when the clutch 110 is in the engaged state, and the following formula (8) is the input side total equivalent inertia weight Iin when the clutch 110 is in the disengaged state. In the following formulas (7) and (8), "Ieng" is the equivalent inertia weight of the engine 102 including a damper (not shown). "Imotor" is the equivalent inertia weight of the electric motor 104. "Iat" is the equivalent inertia weight from the automatic transmission 112 to the input side of the differential gear 28.

(When the clutch is engaged) Iin=Ieng+Imotor+Iat (7)
(When the clutch is released) Iin = Imotor + Iat (8)

When the clutch 110 is engaged, the current differential input torque Tinnow is calculated using the combined torque of the engine torque Te and the motor torque Tm. On the other hand, when the clutch 110 is released, the current differential input torque Tinnow is calculated using only the motor torque Tm.

As described above, the torque calculation unit 82 sets the input side total equivalent inertia weight Iin, which is determined in advance and corresponds to the control state of the clutch 110, as the input side total equivalent inertia weight Iin used to calculate the rattle torque Tgt. The torque calculation unit 82 also calculates the current differential input side torque Tinnow, which corresponds to the control state of the clutch 110.

The torque calculation unit 82 calculates the differential rattle torque Ting using the above formula (4), and then calculates the torque of the power source during rattle according to the control state of the clutch 110. When the clutch 110 is in an engaged state, the torque of the power source during rattle is calculated using the engine torque Te and the motor torque Tm, and when the clutch 110 is in a released state, it is calculated using only the motor torque Tm.

Figure 5 is a flowchart that explains the main control operations of the electronic control unit 80, and is a flowchart that explains the control operations for suppressing rattle shocks and suppressing deterioration of response, and is executed, for example, repeatedly.

5, each step of the flowchart corresponds to a function of the torque calculation unit 82. In S10b, the drive wheel speeds ωrl and ωrr are acquired. In addition, an estimated value of the current engine torque Te and the current motor torque Tm are acquired. In addition, the current gear ratio γat of the automatic transmission 22 is acquired. In addition, the control state of the clutch 110 is acquired. Next, in S15b, it is determined whether the clutch 110 is engaged. If the determination in S15b is positive, in S20b, the input side total equivalent inertia weight Iin and the output side total equivalent inertia weight Iout when the clutch 110 is engaged are calculated. In addition, the current differential input side torque Tinnow is calculated using the combined torque of the engine torque Te and the motor torque Tm, the gear ratio γat of the automatic transmission 22, etc. If the determination in S15b is negative, in S25b, the input side total equivalent inertia weight Iin when the clutch 110 is in the released state, i.e., the input side total equivalent inertia weight Iin excluding the equivalent inertia weight Ieng of the engine 102, and the output side total equivalent inertia weight Iout are calculated. In addition, the current differential input side torque Tinnow is calculated using the motor torque Tm, the speed ratio γat of the automatic transmission 22, etc. Following S20b or S25b, in S30b, the current differential input side rotation change amount dωinnow/dt is calculated using the values obtained by converting the drive wheel speeds ωrl and ωrr to the input side of the differential gear 28 by the differential gear ratio ρ. Next, in S40b, the differential rattle torque Ting is calculated using the input side total equivalent inertia weight Iin, the output side total equivalent inertia weight Iout, the current differential input side torque Tinnow, the current differential input side rotation change amount dωinnow/dt, and the differential gear ratio ρ (see formula (4) above).

As described above, according to this embodiment, the input side total equivalent inertia weight Iin used to calculate the rattle torque Tgt is set to the input side total equivalent inertia weight Iin according to the control state of the clutch 110, and the current differential input side torque Tinnow is calculated according to the control state of the clutch 110. As a result, even in a vehicle 100 equipped with a clutch 110, rattle shocks can be suppressed and deterioration of response can be suppressed, as in the above-mentioned first embodiment.

The calculation formula for the differential rattle torque Ting shown in the above formula (4) can also be applied to the vehicle 200 shown in FIG. 6(a). The vehicle 200 differs from the vehicle 10 in the above-mentioned first embodiment in that the power source is replaced by an electric motor 202. In addition, the vehicle 200 differs from the vehicle 10 in the above-mentioned first embodiment in that the power transmission device 204 provided in the power transmission path between the electric motor 202 and the drive wheels 14 includes an automatic transmission 22 but does not include a torque converter 20.

The calculation formula for the differential rattle torque Ting shown in the above formula (4) can also be applied to the vehicle 300 shown in FIG. 6(b). The vehicle 300 differs from the vehicle 200 in that the power transmission device 302 provided in the power transmission path between the electric motor 202 and the drive wheels 14 is replaced with a transmission mechanism 304 that transmits power not by an automatic transmission 22 but by a simple mechanical mechanism.

The calculation formula for the differential rattle torque Ting shown in the above formula (4) can also be applied to the vehicle 400 shown in FIG. 6(c). The vehicle 400 differs from the vehicle 200 in the above-mentioned second embodiment in that the positional relationship between the engine 102 and the electric motor 104 is swapped. The vehicle 400 has a power transmission device 402 provided in the power transmission path between the electric motor 104 and the drive wheels 106. The power transmission device 402 has a clutch 404 that can cut off the power transmission from the electric motor 104 to the differential gear 116. In the vehicle 400, when the clutch 404 is in a released state, the inertia of the electric motor 104 is excluded from the input side total equivalent inertia weight Iin, and only the estimated value of the engine torque Te is used in the current differential input side torque Tinnow.

As described above, according to this embodiment, similar to the above-mentioned embodiment 1 or embodiment 2, it is possible to suppress rattle shock and suppress deterioration of response.

The above describes in detail an embodiment of the present invention based on the drawings, but the present invention can also be applied in other aspects.

For example, in the above-described embodiment, the automatic transmission 22 and the automatic transmission 112 are planetary gear type automatic transmissions, but are not limited to this. The automatic transmission 22 and the automatic transmission 112 may be a synchronous mesh type parallel two-shaft automatic transmission including a known DCT (Dual Clutch Transmission), a known belt type continuously variable transmission, etc.

Note that the above is merely one embodiment, and the present invention can be implemented in various forms with various modifications and improvements based on the knowledge of those skilled in the art.

10: Vehicle 12: Engine (power source) 14: Drive wheels 16: Power transmission device 22: Automatic transmission (transmission) 24: Transmission output shaft (rotating member) 28: Differential gear (differential device) 30: Drive shaft (rotating member) 32: Engine connecting shaft (rotating member) 34: Transmission input shaft (rotating member) 60: Engine rotation speed sensor (rotation sensor) 62: AT input rotation speed sensor (rotation sensor) 64: AT output rotation speed sensor (rotation sensor) 66: Wheel speed sensor (rotation sensor) 80: Electronic control device (control device) 82: Torque calculation section 100: Vehicle 102: Engine (power source) 104: Electric motor (power source) 106: Drive wheels 108: Power transmission device 110: Clutch 112: Automatic transmission (transmission) 116: Differential gear (differential device) 120: Electronic control device (control device) 200: Vehicle 202: Electric motor (power source) 204: Power transmission device 300: Vehicle 302: Power transmission device 400: Vehicle 402: Power transmission device 404: Clutch

Claims (5)

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 rotation sensor that detects a value corresponding to a rotation speed of a rotating member that constitutes the power transmission device,
A current input torque of the power transmission device;
A current detection value by the rotation sensor;
Setting an output torque of the power transmission device at a time when a rattle occurs, at which a power transmission state of the power transmission device is switched between a driving state and a driven state, to be equal to a current output torque of the power transmission device;
A vehicle control device comprising: a torque calculation unit that calculates a rattle torque, which is an input side torque of the power transmission device at the time of the rattle, based on the torque calculation unit. The vehicle control device according to claim 1, characterized in that the torque calculation unit calculates the rattle torque at a predetermined time point from the start of a transition period in which the power transmission state is switched from one of the driving state and the driven state to the other, until the rattle occurs. the power transmission device includes a differential device that distributes the power to left and right wheels among the drive wheels,
The torque calculation unit
A current input torque of the differential device as the current input torque of the power transmission device;
A change amount of a current input side rotation speed or an output side rotation speed of the differential device as a current detection value by the rotation sensor; and
a predetermined input side total equivalent inertia weight from the power source to the differential device;
a predetermined output-side total equivalent inertia weight from the differential device to the drive wheels;
A gear ratio of the differential device; and
Setting the output side torque of the differential device at the time of the rattle, which is the output side torque of the power transmission device at the time of the rattle, to a value equal to the current output side torque of the differential device, which is the current output side torque of the power transmission device;
3. The vehicle control device according to claim 1, wherein the input torque of the differential device at the time of the rattle is calculated as the rattle torque based on the above equation. the power transmission device includes a transmission in a power transmission path between the power source and the differential device,
4. The vehicle control device according to claim 3, wherein the torque calculation unit sets a predetermined input side total equivalent inertia weight according to a gear ratio of the transmission as the input side total equivalent inertia weight. the power transmission device includes an engine and an electric motor as the power source, and a clutch capable of interrupting power transmission from the engine or the electric motor to the differential device,
4. The vehicle control device according to claim 3, wherein the torque calculation unit sets a predetermined input side total equivalent inertia weight according to a control state of the clutch as the input side total equivalent inertia weight, and calculates the current input side torque of the differential device according to the control state of the clutch.

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