JP5467035B2 - Vehicle control device - Google Patents

Description

  The present invention relates to a vehicle control device, and more particularly to a vehicle control device that rusts a friction surface of a friction braking rotary member when the vehicle starts.

  A vehicle such as an automobile is provided with a friction braking device (hydraulic brake) that generates a friction braking force on a friction surface of a braking rotating member such as a disk rotor that rotates in accordance with the rotation of a wheel.

  Since the brake rotating member is made of metal, if friction braking is not performed for a long period of time, rust is generated on the friction surface of the brake rotating member. The rusting on the friction surface causes the braking performance to fluctuate and the appearance merchantability to deteriorate.

  In contrast, when the vehicle starts, the friction braking means is controlled so as to generate a friction braking force regardless of the operation of the brake pedal, and the rust generated on the friction surface of the braking rotating member is removed when the vehicle starts. It has been proposed to perform braking (for example, Patent Document 1).

JP 2008-132906 A

  However, in the conventional rust removal braking at the start of the vehicle, since the rusting of the friction surface is detected after the vehicle starts, the rust removal braking cannot be performed at the same time as the vehicle starts. It may be in a state where it is not done. Also, in the conventional rust removal braking at the start of the vehicle, the execution time of the rust removal braking is set according to the rust generation amount of the friction surface, but it is uniquely determined without considering the rust generation amount of the friction surface. Since it takes a long time to remove rust and the amount of rusting is large, sufficient rust removal is not performed during the first braking operation after starting the vehicle. It becomes a state.

  On the other hand, if the friction braking force of rust removal braking when starting the vehicle is increased, the rust removal time will be shortened, and even when the amount of rust generation is large, sufficient rust removal will be performed during the first brake operation after the ignition switch is turned on. Can be guaranteed. However, if the friction braking force for rust removal braking at the start of the vehicle is increased, dragging due to braking, that is, vehicle drive resistance increases, and energy economy (fuel economy) deteriorates.

  The problem to be solved by the present invention is to ensure that rust removal has already been performed at the time of brake operation immediately after starting the vehicle, and further, the rust removal of the friction surface is early according to the degree of rust formation on the friction surface when the vehicle starts. In addition, it is ensured that the process is performed in a short time, and at the same time, the deterioration of energy economy (fuel economy) is reduced.

The vehicle control apparatus according to the present invention controls a vehicle having friction braking means (19) for generating a friction braking force on a friction surface (15A) of a braking rotating member (15) that rotates in accordance with rotation of a vehicle wheel. In the apparatus, friction surface rust detection means (49) for quantitatively detecting the amount of rust generated on the friction surface (15A) of the braking rotating member (15) when the vehicle main power is turned on, and after the vehicle main power is turned on The friction braking means (19) is frictionally controlled by an amount quantitatively determined according to the amount of rusting of the friction surface (15A) detected by the friction surface rust detection means (49) at the first start of the vehicle. Braking control means (47) for performing control to generate power.

  According to this configuration, the friction surface rust detection means (49) detects rust on the friction surface (15A) of the brake rotating member (15) when the vehicle is powered on prior to vehicle start. If the friction surface (15A) of the rotating member (15) is rusted, braking for rust removal starts at the same time as the first start after turning on the main power of the vehicle, and rust removal has already been performed at the time of braking operation immediately after the vehicle starts. Can be guaranteed.

Furthermore, rust-up of the friction surface in response to the rusting degree of friction surface when the vehicle is started (15A) (15A) is guaranteed to be performed in a short time earlier, together worsening of the energy economy and is reduced.

The vehicle control apparatus according to the present invention controls a vehicle having friction braking means (19) for generating a friction braking force on a friction surface (15A) of a braking rotating member (15) that rotates in accordance with rotation of a vehicle wheel. In the apparatus, friction surface rust detection means (49) for detecting rusting of the friction surface (15A) of the braking rotating member (15) when the vehicle main power is turned on, and vehicle speed detection means for detecting the vehicle speed of the vehicle. (41), and when the rusting of the friction surface (15A) is detected by the friction surface rust detection means (49) at the first start after turning on the main power of the vehicle, the friction braking is performed. The means (19) performs control to generate a friction braking force, and when the vehicle speed detected by the vehicle speed detection means (41) exceeds a predetermined value, the generation amount of the friction braking force at the start is made zero, and the friction Vehicle speed at which the amount of braking force generated is zero The set enough lower speed is less rusting of the friction surfaces is sensed by the friction surface rusting detecting means (49) (15A).

  According to this configuration, it is ensured that rust removal of the friction surface (15A) is performed in a short time according to the degree of rusting of the friction surface (15A) when the vehicle starts, and further the deterioration of energy economy is further reduced. be able to.

  According to the vehicle control device of the present invention, it is ensured that rust removal of the friction surface is performed in a short time in accordance with the degree of rusting of the friction surface at the start of the vehicle, and the deterioration of energy economy is also reduced. .

1 is an overall configuration diagram showing an embodiment of an automobile to which a vehicle control device according to the present invention is applied. 1 is a block diagram showing an embodiment of a driving / braking system for an electric vehicle including a vehicle control device according to the present invention. The flowchart which shows the control routine at the time of start in the vehicle control apparatus by this embodiment. The flowchart which shows the rust generation amount estimation routine in the vehicle control apparatus by this embodiment. The flowchart which shows the rust removal start control routine in the vehicle control apparatus by this embodiment. The graph which shows the relationship between the vehicle leaving time and rust removal execution amount in the vehicle control apparatus by this embodiment. The graph which shows the relationship between the vehicle leaving time in the vehicle control apparatus by this embodiment, and the friction braking force at the time of start. The graph which shows the relationship between the vehicle leaving time in the vehicle control apparatus by this embodiment, and the braking end vehicle speed at the time of start. The flowchart which shows other embodiment of the rust generation amount estimation routine in the control apparatus for vehicles by this invention.

  Hereinafter, an embodiment in which a vehicle control device according to the present invention is applied to an electric vehicle will be described with reference to FIGS.

  As shown in FIG. 1, the electric vehicle 1 has a pair of left and right front wheels 3 and a rear wheel 5. A motor / generator 9 is connected to the front wheel axle 7 connected to the left and right front wheels 3 in a torque transmission relationship. The illustration of the differential mechanism provided on the front wheel axle 7 is omitted.

  The motor / generator 9 serves as both a vehicle-driving motor and a regenerative generator. The battery 11 serving as a secondary battery serves as a power source, and the power supply from the battery 11 and the power supply to the battery 11 are performed by the inverter 13. (Recharging) is controlled, and at the time of deceleration, regenerative braking means for converting regenerative energy into electric power and generating regenerative braking force is achieved.

  The front wheel 3 and the rear wheel 5 are pressed against the friction surface 15A of the disk rotor 15 and the disk rotor 15 which is a braking rotating member that rotates in accordance with the rotation of each wheel as friction braking means for performing friction braking. A known disc brake 19 including a caliper 17 having a brake pad for generating a braking force is provided for each wheel.

  A common brake fluid pressure generator 23 is connected to the caliper 17 of each wheel by a hydraulic pipe 21. The brake fluid pressure generating device 23 is a known electro-hydraulic device including a brake hydraulic cylinder that is driven by an electric motor to quantitatively generate brake fluid pressure, and is an electronic control unit (hereinafter referred to as an ECU). A brake-by-wire type hydraulic brake is configured under the regenerative cooperative braking control by 31.

  The ECU 31 is based on a microcomputer, and a signal indicating an accelerator pedal operation amount (accelerator pedal depression amount) from an accelerator pedal operation amount sensor 35 provided on the accelerator pedal 33 is sent to a brake pedal operation provided on the brake pedal 37. A sensor signal indicating the brake pedal operation amount (brake pedal depression amount) from the amount sensor 39, and a sensor signal indicating the wheel speed from the wheel speed sensors (vehicle speed detection means) 41 provided on the respective wheels of the front wheel 3 and the rear wheel 5. Then, a sensor signal relating to ignition switch ON / OFF is input from an ignition switch 43 which is a main power switch of the vehicle. The ECU 31 calculates an average value of wheel speeds detected by the wheel speed sensor 41 of each wheel, and calculates a vehicle speed.

  As shown in FIG. 2, the ECU 31 embodies a motor / generator control unit 45, a braking control unit 47, and a rust generation amount estimation unit 49 by executing a computer program.

  The motor / generator control unit 45 includes the above-described sensor signal, an accelerator pedal operation amount detected exclusively by the accelerator pedal operation amount sensor 35, and a motor / generator control unit based on a predetermined driving / regeneration control law. In response to the command signal from 45, the driving drive / regenerative control is calculated and a command signal based on the calculation result is output to the inverter 13. The inverter 13 is configured to supply power to the motor / generator 9 from the battery 11, that is, travel drive, and supply power (charge) to the battery 11 from the motor / generator 9, that is, regeneration, in response to a command signal from the motor / generator control unit 45. To control.

The brake control unit 47 is activated when the brake pedal 37 is depressed based on a sensor signal from the brake pedal operation amount sensor 39, that is, activated when the brake is operated, and a predetermined regenerative cooperative braking control law is established. Based on the aforementioned sensor signal and the brake pedal operation amount detected exclusively by the brake pedal operation amount sensor 39, the brake control operation processing is performed, and the regenerative braking command signal based on the operation result is controlled by the motor / generator control. A friction brake command signal is output to the brake fluid pressure generator 23 to the unit 45.

  The rust generation amount estimation unit 49 is a friction surface rust detection means, and when the ignition switch 43 is turned on for rust removal start control, which will be described later, prior to vehicle start, the disc rotor 15 which is a braking rotary member. The amount of rusting on the friction surface 15A is quantitatively estimated from the time the vehicle is left. The vehicle leaving time is the time from when the ignition switch 43 changes from on to off until the next time that the ignition switch 43 changes from off to on. This time can be measured by the built-in timer of the ECU 31. it can. As one embodiment, the rust generation amount estimation unit 49 estimates that the rust generation amount of the friction surface 15A increases in proportion to the length of the vehicle leaving time.

  The above-described braking control unit 47 further includes the friction surface of the disc rotor 15 estimated by the rusting amount estimation unit 49 when the vehicle starts for the first time after the ignition switch 43 changes from OFF to ON (at the first start). The disc brake 19 performs braking control for rust removal in which the disc brake 19 generates friction braking force with an amount quantitatively determined according to the rusting amount of 15A.

  The rust generation amount estimation unit 49 detects the rust generation amount of the friction surface 15A of the disk rotor 15 when the ignition switch 43 is turned on, that is, when the main power supply of the vehicle is turned on, before starting the vehicle. If the 15 friction surfaces 15A are rusted, braking for removing rust is started simultaneously with the first start after the main power of the vehicle is turned on. This ensures that rust removal has already been performed at the time of brake operation immediately after starting the vehicle.

  The start-up braking for rust removal may be controlled to increase the execution time as the rust generation amount of the friction surface 15A estimated by the rust generation amount estimation unit 49 increases.

  In addition, when starting the vehicle for rust removal, speed limit control may be added to make the amount of friction braking force generated zero when the vehicle speed calculated by the ECU 31 reaches a predetermined value (the vehicle speed at the time of starting braking ends). . In this case, as the rusting amount of the friction surface 15A of the disk rotor 15 estimated by the rusting amount estimation unit 49 is smaller, the braking end vehicle speed at start can be set to the lower speed side.

  Further, when braking control for rust removal is performed at the time of starting the vehicle, the motor / generator control unit 45 performs control for compensating for the traveling drive resistance generated by the friction braking force of the rust removal braking by the motor output of the motor / generator 9, that is, Then, control is performed to increase the motor output by the reduction of the running force generated by the friction braking force.

  The start of the vehicle means that the accelerator pedal 33 is depressed, and the start of the vehicle can be detected by the sensor output of the accelerator pedal operation amount sensor 35.

  Next, the procedure of the starting control executed by the ECU 31 will be described with reference to the flowcharts shown in FIGS.

FIG. 3 shows a general routine for starting control. This routine is executed when the depression of the accelerator pedal 33 is detected by the accelerator pedal operation amount sensor 35. First, it is determined whether or not this is the first start after the ignition switch 43 is changed from OFF to ON. Is determined (step S10).

  If it is the first start after the ignition switch is turned on (Yes at Step S10), the rust removal start control routine is called and the routine is executed (Step S11).

  On the other hand, if it is not the first start after the ignition switch is turned on (Yes at step S10), a normal start control routine is called and the routine is executed (step S12). In normal start control, friction braking is not performed, and the motor output of the motor / generator 9 is controlled only for running.

  Next, prior to the description of the rust removal braking control routine, the rust generation amount estimation routine by the rust generation amount estimation unit 49 will be described with reference to the flowchart shown in FIG. The rusting amount estimation routine is repeatedly executed every predetermined time including when the ignition switch is turned off.

  In this routine, first, it is determined whether or not the ignition switch 43 is off (step S20). If the ignition switch 43 is off (Yes at Step S20), that is, if the vehicle is left unattended, the timer value T of the ECU 31 is incremented (Step S21).

  Next, it is determined whether or not the timer value T is equal to or greater than the first predetermined value A1, the second predetermined value A2, or the third predetermined value A3 (steps S22 to S24). ). These predetermined values have a relationship of A1> A2> A3, and are used to estimate the rusting amount of the friction surface 15A step by step according to the standing time. In addition, estimating the amount of rusting step by step is to estimate the amount of rusting quantitatively, and as the number of steps increases, it approaches to estimating the amount of rusting continuously. It will be.

  When A2> T ≧ A3 (Yes in step S24), it is highly possible that the friction surface 15A is rusting that requires rust removal, but the determination that the rusting amount of the friction surface 15A is still small. Is performed (step S25). If A1> T ≧ A2 (Yes at Step S23), it is determined that the amount of rust on the friction surface 15A is medium (Step S26). If T ≧ A1 (Yes at Step S22), it is determined that the amount of rusting on the friction surface 15A is large (Step S26). If T <A3 (No in step S24), that is, if left for a short period of time, the current timer is determined without performing the rusting amount determination, assuming that the friction surface 15A does not rust enough to require rust removal. The routine is terminated while the value T is held.

  When the ignition switch 43 is on (No at Step S20), it is determined whether or not the rust removal start control has been executed since the ignition switch 43 is changed from off to on this time, that is, from the time of the current vehicle restart. Is performed (step S28). If the rust removal start control is being executed (Yes at Step S28), the timer value T is reset to zero (Step S29). On the other hand, if the rust removal start control is not executed (No at Step S28), the routine is terminated while the current timer value T is maintained.

  By this rust generation amount estimation routine, when the ignition switch 43 is turned on, the rust generation amount of the friction surface 15A is quantitatively detected. In this embodiment, the amount of rusting on the friction surface 15A is determined in three stages of large, medium, and small.

  Next, the rust removal start control routine called in step S11 of the general flow will be described with reference to the flowchart shown in FIG.

  In this routine, first, it is determined whether or not the rust removal execution amount N has been determined (step S30). If the rust removal execution amount N has not been determined (No at Step S30), the rust removal execution amount N is determined, and the counter value C of the ECU 31 is set to the rust removal execution amount N. The rust removal execution amount N is a time during which rust removal braking is performed, and is set to a larger value as the vehicle leaving time that is known from the timer value T is longer as shown in FIG.

  Although the setting of the rust removal execution time is not essential, the rust removal of the friction surface 15A can be more reliably performed without excess or deficiency by setting the time.

  If the rust removal execution amount N has been determined, it is determined whether or not the current counter value C is equal to or greater than “1” (step S32). When C ≧ 1 (Yes at step S32), it is determined whether the determination of the rust amount performed in the estimation of the rust amount is large, medium, small, or no determination (steps S33 to S35). ).

  If the determination of the amount of rusting is large (Yes at step S33), the disc brake 19 performs a process of generating a friction braking force that is 100% of a predetermined starting braking force (step S36). Thereby, when the rusting amount of the friction surface 15A is large, the rusting of the friction surface 15A by friction by the maximum braking at the start is efficiently and effectively performed, and the rusting amount of the friction surface 15A is large. Even if it exists, rust removal of 15 A of friction surfaces is completed in a short time. This maximum braking at the start ensures that even when the rusting amount of the friction surface 15A is large, sufficient rust removal is performed in a short time during the first brake operation after the vehicle starts.

  The starting braking force is a friction braking force corresponding to several to several tens of percent of the friction braking force of the disc brake 19 when the brake pedal operation amount is maximum.

  If the determination of the amount of rusting is in progress (Yes at step S34), the disc brake 19 performs a process of generating a friction braking force that is n% of the braking force at the start (step S36). n% is other than 0% and 100%, and preferably an appropriate value is selected from 75% to 25%. Further, n% of the starting braking force may be variably set in a stepwise manner according to the vehicle leaving time that is known from the timer value T.

  When the rusting amount of the friction surface 15A is medium, rust removal of the friction surface 15A due to friction by the braking force at the time of starting is smaller than in the case of being large, and in this case also after the vehicle starts When the brakes are operated for the first time, sufficient rust removal is ensured in a short time. By limiting the starting braking force to a value lower than the maximum value in this way, drag resistance due to braking is reduced as compared with the case where starting braking is performed at the maximum value, and deterioration of energy economy is reduced.

  If the determination of the amount of rusting is small (Yes at step S35), the vehicle speed at which the disc brake 19 generates a friction braking force of n% of the braking force at the start and ends the braking at the start is determined as the rusting amount. A process of changing from the end vehicle speed to the low speed side when the determination is large or medium is performed (step S38).

  As described above, when the amount of rusting is small, the braking force at the time of starting is lower than the maximum value (n%), and the braking at the time of starting is completed at a low vehicle speed. Deterioration of energy economy is further reduced while ensuring that the process is performed in a short time.

  As shown in FIG. 8, the control may be performed to quantitatively change the starting braking end vehicle speed to a higher vehicle speed as the vehicle leaving time is longer.

  During the period in which the start-time braking is being executed, control is performed to compensate the travel drive resistance generated by the friction braking force of start-time braking (rust removal braking) by the motor output of the motor / generator 9 (step S39). By this compensation control, it is avoided that the accelerator feeling fluctuates during braking at the time of start.

And if the start time of braking is performed, and decrements the counter value C (step S40), and terminates the routine.

  If C ≧ 1 is not satisfied (No in step S32), that is, if C = 0, or if there is no determination in rusting amount estimation (No in step S35), the current rusting amount determination is reset (step S41). Then, a rust removal start control completion process is performed (step S42), and then the routine ends. Thereby, the braking at the start is limited to a time determined by the rust removal execution amount N.

  If the ECU 31 is in an environment where the current time can be acquired from the outside by wireless communication, such as time information output from a GPS satellite, regardless of the timer of the ECU 31, the vehicle leaving time can be measured without using the timer of the ECU 31. You can do it. In this case, the ECU 31 can be cut off when the ignition switch is turned off, thereby saving power.

  A rusting amount estimation routine in the case of obtaining the current time from the outside and calculating the vehicle leaving time will be described with reference to the flowchart shown in FIG. This rusting amount estimation routine is executed when the on / off state of the ignition switch 43 changes.

  First, it is determined whether or not the changed ignition switch 43 is off (step S50). If the ignition switch 43 is off (Yes at step S50), a process of writing the time acquired when the ignition switch 43 is turned off to the memory of the ECU 31 is performed (step S51). When the writing is completed, the ECU 31 is turned off immediately after that (step S52). The memory for storing the time is a self-holding type memory that holds the stored contents even when the ECU 31 is powered off.

  If the ignition switch 43 is on (No at step S50), the ECU 31 is turned on (step S53), and the time acquired when the ignition switch 43 is turned on is written into the memory of the ECU 31 (step S54).

  Next, the leaving time L is calculated from the time difference between the time stored value at the time of ignition switch off and the time stored value at the time of ignition switch on (step S55).

  Next, it is determined whether or not the calculated standing time L is greater than or equal to the first predetermined value B1, greater than or equal to the second predetermined value B2, or greater than or equal to the third predetermined value B3 (step S56). To S58). These predetermined values have a relationship of B1> B2> B3, and are used to estimate the rusting amount of the friction surface 15A stepwise according to the standing time L.

  If B2> L ≧ B3 (Yes at step S58), it is highly possible that the friction surface 15A is rusting that requires rust removal, but it is determined that the amount of rusting on the friction surface 15A is still small. Is performed (step S61). If B1> L ≧ B2 (Yes at Step S57), it is determined that the amount of rusting on the friction surface 15A is medium (Step S60). When L ≧ B1 (Yes at Step S56), it is determined that the amount of rusting on the friction surface 15A is large (Step S59). When L <B3 (No at Step S58), that is, when left for a short time, the friction surface 15A is not rusted to the extent that rust removal is required, and the rusting amount determination is not performed. Finally, the time storage value is cleared (step S62), and the routine ends.

  Note that the amount of rusting on the friction surface 15A can be directly detected by image processing of the captured image of the friction surface 15A, reflected light observation, or the like, in addition to the estimation based on the vehicle leaving time. Further, if the torque fluctuation (current value fluctuation) of the electric servo motor at the time of the previous vehicle start is greater than or equal to a predetermined value, the friction surface 15A may be rusted and rust removal braking may be performed from the start of the vehicle.

  In addition, torque compensation during braking for start-up for rust removal is performed by the motor output in the case of an electric vehicle, but in the case of a hybrid vehicle, at least one of the motor output and the internal combustion engine output, the internal combustion engine In the case of an automobile using only a prime mover, it can be performed by the output of the internal combustion engine.

  In the case of an electric vehicle, the main power on of the vehicle means that the power circuit of the motor is turned on. In the case of a hybrid vehicle, the power circuit of the motor and the ignition circuit of the internal combustion engine are turned on. In other words, in the case of an automobile using only the internal combustion engine as a prime mover, it means that the ignition circuit of the internal combustion engine is turned on.

DESCRIPTION OF SYMBOLS 1 Electric vehicle 3 Front wheel 5 Rear wheel 9 Motor generator 15 Disc rotor 17 Caliper 19 Disc brake 23 Brake fluid pressure generator 31 Electronic control unit (ECU)
35 accelerator pedal operation amount sensor 39 brake pedal operation amount sensor 41 wheel speed sensor (vehicle speed detection means)
43 Ignition switch 45 Motor / generator controller 47 Braking controller 49 Rust estimation unit

Claims (2)

In a vehicle control device having friction braking means for generating a friction braking force on a friction surface of a braking rotating member that rotates in accordance with rotation of a vehicle wheel,
Friction surface rust detection means for quantitatively detecting the amount of rust generated on the friction surface of the braking rotating member when the vehicle main power is turned on;
The friction braking means generates a friction braking force with an amount quantitatively determined according to the amount of rusting of the friction surface detected by the friction surface rust detection means at the first start after turning on the main power of the vehicle. Braking control means for performing control,
Brake device for vehicles. In a vehicle control device having friction braking means for generating a friction braking force on a friction surface of a braking rotating member that rotates in accordance with rotation of a vehicle wheel,
Friction surface rust detection means for detecting rust on the friction surface of the braking rotating member when the vehicle main power is turned on;
Vehicle speed detecting means for detecting the vehicle speed of the vehicle,
When the friction surface rust detection means detects the rust of the friction surface at the first start after turning on the main power of the vehicle, the friction braking means performs control to generate a friction braking force, and the vehicle speed When the vehicle speed detected by the detecting means exceeds a predetermined value, the friction braking force generation amount at the time of start is zeroed, and the vehicle speed at which the friction braking force generation amount is zero is detected by the friction surface rust detection means. The braking device for vehicles which sets to the low speed side, so that there is little rusting of the said friction surface .

Images