JP4622729B2 - Body speed calculation device - Google Patents

Description

  The present invention obtains wheel speeds of front and rear wheels from detection signals from wheel speed sensors provided for front and rear wheels in a motorcycle, and determines vehicle body speed (estimated vehicle body) based on the obtained wheel speeds of front and rear wheels. The present invention relates to a vehicle body speed calculation device that calculates (speed).

  Conventionally, for example, in a four-wheel vehicle driven by a rear wheel, it is not reliable due to the influence of acceleration slip or the like, so the wheel of the front wheel that is the driven wheel, not the wheel speed of the rear wheel that is the driving wheel. Speed is used for vehicle speed calculation. When the wheel speed sensor provided for the front wheels breaks down on both the left and right front wheels, the wheel speed of the rear wheel that will eventually become the driving wheel is used for the vehicle speed calculation.

At this time, since the situation is different from the case where the vehicle speed calculation is performed using the wheel speed of the front wheel, correction may be performed when the vehicle speed calculation is performed using the wheel speed of the rear wheel (Patent Document 1). reference). For example, considering that the wheel diameter is different between the front wheel and the rear wheel, the vehicle speed is obtained by multiplying the difference in the wheel diameter by the wheel speed of the rear wheel as a correction constant.
JP-A-8-268252

  In a motorcycle, basically, the vehicle speed can be calculated using the wheel speed of the front wheel that is the driven wheel, and the vehicle speed can be calculated supplementarily using the wheel speed of the rear wheel. In this case, since the situation for a motorcycle is different from the case where the vehicle speed calculation is performed using the wheel speed of the front wheel, it is necessary to perform correction when the vehicle speed calculation is performed using the wheel speed of the rear wheel. There is.

  However, in the case of a motorcycle, it is preferable to perform correction in consideration of the influence of acceleration slip of the rear wheel rather than the difference in wheel diameter between the front wheel and the rear wheel. The effect of this acceleration slip is different from the above-mentioned correction considering the difference between the wheel diameters of the front wheels and the rear wheels, and cannot be dealt with with a fixed correction constant, but simply multiplying the wheel speed of the rear wheel by a fixed correction constant. The exact vehicle speed cannot be determined just by combining them. As a result, for example, there is a problem that accurate vehicle speed display cannot be performed or appropriate ABS control cannot be performed.

  The present invention has been made in view of the above points, and it is an object of the present invention to provide a vehicle body speed calculation device that can accurately determine a vehicle body speed even when performing vehicle body speed calculation using the wheel speed of a rear wheel in a motorcycle. And

  In order to achieve the above object, according to the first aspect of the present invention, when both the front wheel speed sensor (23) and the rear wheel speed sensor (24) are normal, the wheel speed ratio storage means (110, 120), an estimated vehicle speed (VS0) is obtained based on at least one of the front wheel (FW) wheel speed and the rear wheel (RW) wheel speed, and the front wheel (FW) wheel speed and rear wheel (RW) A wheel speed ratio, which is a ratio of wheel speeds, is obtained, and the wheel speed ratio is stored in association with the estimated vehicle speed (VS0), and the vehicle body speed calculation means (140, 160, 200, 210) Based on the wheel speed, the estimated vehicle speed (VS0) is obtained, and the wheel speed ratio stored in the wheel speed ratio storage means (110, 120) corresponding to the obtained estimated vehicle speed (VS0) is used. Wheel (RW) car It is characterized by calculating a vehicle speed (SP1) by correcting the speed.

  As described above, when the wheel speed ratio is stored in association with the estimated vehicle speed (VS0), even if the acceleration slip of the rear wheel (RW) fluctuates according to the vehicle speed, the wheel speed taking into account it. The ratio can be stored. Accordingly, when the vehicle body speed (SP1) is obtained using the wheel speed of the rear wheel (RW) serving as the driving wheel, it is possible to obtain the accurate vehicle body speed (SP1). Thus, for example, as shown in claim 10, by outputting the vehicle speed (SP1) obtained by the vehicle speed calculation device to the vehicle speed meter (30), the vehicle speed meter (30) can accurately display the vehicle speed. It becomes possible to do. In addition, when the vehicle body speed calculation device is applied to the brake fluid pressure control device, it is possible to accurately execute brake fluid pressure control such as ABS control based on the accurate vehicle body speed (SP1).

  In the invention according to claim 2, the wheel speed ratio storage means (110, 120) is used to store the obtained wheel speed ratio based on the vehicle body deceleration obtained from the estimated vehicle speed (VS0). It is characterized by determining.

  In this way, it is possible to determine whether or not to use the obtained wheel speed ratio as a memory based on the vehicle body deceleration. For example, if the vehicle deceleration exceeds a predetermined threshold, it can be excluded as a wheel speed ratio based on a wheel speed with poor reliability while driving on a gravel road etc. It becomes.

  Further, as described in claim 3, the wheel speed ratio storage means (110, 120) sets a range assumed as a wheel speed ratio corresponding to the estimated vehicle speed (VS0) as a specified range, and is thus obtained. Whether or not the obtained wheel speed ratio is used for storing the wheel speed ratio can also be determined based on whether the wheel speed ratio is within the specified range or outside the specified range.

  In the invention according to claim 4, the wheel speed ratio storage means (110, 120) is configured to store the wheel speed ratio in a plurality of speed regions, and the estimated vehicle speed (VS0) is a plurality of speeds. It is characterized by determining which of the regions corresponds to the wheel and storing the wheel speed ratio in association with the determined region. Thus, it is possible to store the wheel speed ratio by dividing into a plurality of speed regions.

  Further, the invention according to claim 5 is characterized in that the wheel speed ratio storage means (110, 120) stores a value such that the wheel speed ratio increases linearly as the estimated vehicle speed (VS0) increases. . In this way, the wheel speed ratio can be stored as a value that changes linearly in accordance with the estimated vehicle speed (VS0). In this way, it is possible to prevent the vehicle body speed from changing stepwise at the speed at which the speed area is switched as in the case where the wheel speed ratio is stored in a plurality of speed areas. .

  According to the sixth aspect of the present invention, when both the front wheel speed sensor (23) and the rear wheel speed sensor (24) are normal, the front wheel brake determining member (130) uses the front wheel brake operating member ( When it is determined that 11) is operated, the vehicle body speed calculation means (140, 160, 200, 210) uses the wheel speed ratio stored in the wheel speed ratio storage means (110, 120) to The vehicle speed (SP1) is calculated by correcting the wheel speed of the wheel (RW).

  As described above, when the front wheel (FW) is being braked, it is not preferable to calculate the vehicle body speed using the wheel speed of the front wheel (FW) even if the front wheel (FW) is a driven wheel. . Therefore, by obtaining the vehicle body speed (SP1) using the wheel speed of the rear wheel (RW), it is possible to obtain a relatively accurate vehicle body speed (SP1).

  In the seventh aspect of the present invention, when both the front wheel speed sensor (23) and the rear wheel speed sensor (24) are normal, the front wheel brake determining means (130) uses the front wheel brake operating member ( 11) If it is determined that the rear-wheel braking determination means (150) determines that the rear-wheel brake operation member (12) is operated, the vehicle body speed calculation means ( 140, 160, 200, 210) calculates the vehicle body speed (SP1) using the wheel speed of the front wheel (FW) without using the wheel speed ratio stored in the wheel speed ratio storage means (110, 120). It is characterized by that.

  Thus, when the rear wheel (RW) is also being braked, both the wheel speed of the front wheel (FW) and the wheel speed of the rear wheel (RW) are unreliable, but the front wheel (FW) It is considered preferable to perform wheel speed calculation using the wheel speed. For this reason, in such a case, by obtaining the vehicle body speed (SP1) using the wheel speed of the front wheel (FW), it is possible to obtain a relatively accurate vehicle body speed (SP1).

  In the invention described in claim 8, when the front wheel speed sensor (23) is normal and the rear wheel speed sensor (24) is abnormal, the vehicle body speed calculation means (140, 160, 200). 210) is characterized in that the vehicle body speed (SP1) is calculated using the wheel speed of the front wheel (FW) without using the wheel speed ratio stored in the wheel speed ratio storage means (110, 120). .

  Thus, when the front wheel speed sensor (23) is normal and the rear wheel speed sensor (24) is abnormal, the vehicle speed ( By obtaining SP1), it is possible to obtain an accurate vehicle speed (SP1).

  According to the ninth aspect of the present invention, when the front wheel speed sensor (23) is abnormal and the rear wheel speed sensor (24) is normal, the vehicle body speed calculating means (140, 160, 200). 210) determines whether or not the wheel speed ratio is already stored in the wheel speed ratio storage means (110, 120), and if it is stored, stores it in the wheel speed ratio storage means (110, 120). The vehicle speed (SP1) is calculated by correcting the wheel speed of the rear wheel (RW) using the wheel speed ratio thus determined. If not yet stored, the wheel speed ratio storage means (110, 120) The vehicle speed (SP1) is calculated by correcting the wheel speed of the rear wheel (RW) using the default value of the wheel speed ratio stored in advance.

  Thus, when the front wheel speed sensor (23) is abnormal and the rear wheel speed sensor (24) is normal, the vehicle speed is determined using the wheel speed of the rear wheel (RW). By obtaining (SP1), it is possible to obtain an accurate vehicle speed (SP1). In this case, when the wheel speed ratio is not yet stored in the wheel speed ratio storage means (110, 120), the vehicle body speed (SP1) can be obtained using the default value.

  In addition, the code | symbol in the bracket | parenthesis of each said means shows the correspondence with the specific means as described in embodiment mentioned later.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings.

(First embodiment)
FIG. 1 shows an overall configuration of a brake fluid pressure control device 1 for a motorcycle equipped with a vehicle body speed calculation device to which an embodiment of the present invention is applied. This brake fluid pressure control device 1 has a first piping system that generates a braking force for the front wheels FW and a second piping system that generates a braking force for the rear wheels RW.

  As shown in FIG. 1, the brake hydraulic pressure control device 1 is provided with a brake lever 11 positioned on the right handle and a brake pedal 12 positioned in front of the right footrest. The brake lever 11 and the brake pedal 12 correspond to brake operation members for generating a braking force for the front wheel FW and the rear wheel RW, respectively, and are operated independently by the driver. The brake lever 11 and the brake pedal 12 are connected to a brake circuit having first and second piping systems via a master cylinder (hereinafter referred to as M / C) not shown.

  The brake lever 11 is connected to a first piping system that generates a braking force for the front wheels FW via an M / C or the like. The first piping system has a pipeline A as a main pipeline connected to the M / C that generates brake fluid pressure according to the operation of the brake lever 11, and is provided to the front wheel FW through this pipeline A. It is connected to a wheel cylinder (hereinafter referred to as W / C) 13. For this reason, the M / C pressure generated in the M / C in accordance with the operation of the brake lever 11 is transmitted to the W / C 13 through the pipe line A.

  Further, a pipeline B as a pressure reducing pipeline is connected to the pipeline A. A reservoir 14 is connected to the pipeline B, and a pressure reduction control valve 15 is disposed on the upstream side of the reservoir 14 in the pipeline B, that is, on the pipeline A side. Further, a conduit C serving as a reflux conduit is disposed so as to connect the reservoir 14 and the conduit A. The pipe C is provided with a pump 17 driven by a motor 16 so as to suck and discharge brake fluid from the reservoir 14 toward the pipe A.

  The reservoir 14 is configured to allow the brake fluid to flow up to a predetermined capacity. In the reservoir chamber 14a of the reservoir 14, there are provided a piston 14b having a predetermined stroke and a spring 14c for biasing the piston 14b in a direction for discharging the brake fluid in the reservoir chamber 14a.

  The reservoir 14 configured in this manner releases the brake fluid that generates the W / C pressure with respect to the W / C 13, and when the suction is performed by the pump 17, the stored brake fluid is discharged toward the pump 17. It is supposed to be.

  The pressure reduction control valve 15 is constituted by a normally closed two-position electromagnetic valve capable of controlling the communication / blocking state between the W / C 13 and the reservoir 14, for example. Since the pressure reducing control valve 15 is in a non-excited state during normal braking, it is always cut off.

  On the other hand, the brake pedal 12 is connected to a second piping system that generates a braking force for the rear wheel RW via an M / C or the like. The second piping system has a pipeline D as a main pipeline connected to the M / C that generates brake fluid pressure according to the operation of the brake pedal 12, and is provided to the rear wheel RW through this pipeline D. It is connected to W / C18. Since the second piping system has the same configuration as the first piping system, detailed description of individual components will not be made, but the pipeline D is the pipeline A and the pipeline E is the pipeline. B, a pipe F is provided as a pipe C, a pressure reduction control valve 19 is provided as a pressure reduction control valve 15, a reservoir 20 is provided as a reservoir 14, and a pump 21 is provided as a pump 17.

  The brake hydraulic pressure control device 1 is provided with a brake ECU 22. The brake ECU 22 functions as a wheel speed calculation device, and is constituted by a known microcomputer having a CPU, ROM, RAM, I / O, and the like. Various processes such as a control process are executed.

  Based on the electric signal from the brake ECU 22, voltage application control to the motor 16 for driving the pressure-reducing control valves 15 and 19 and the pumps 17 and 21 in the brake hydraulic pressure control device 1 configured as described above is performed. It is supposed to be executed. Thereby, the W / C pressure generated in each of the W / Cs 13 and 18 is controlled.

  The brake fluid pressure control device 1 is also provided with wheel speed sensors 23 and 24. The wheel speed sensors 23 and 24 are arranged corresponding to the front wheel FW and the rear wheel RW, respectively, and send the rotation speed of the front wheel FW and the rear wheel RW, that is, a pulse signal having a pulse number proportional to the wheel speed to the brake ECU 22. Output. Therefore, the brake ECU 22 obtains the wheel speeds of the front wheel FW and the rear wheel RW based on the detection signals from the wheel speed sensors 23 and 24, and obtains the vehicle body speed using the wheel speeds. Brake fluid pressure control such as ABS control is executed.

  Furthermore, the brake fluid pressure control device 1 is also provided with stop switches 25 and 26. The stop switches 25 and 26 are arranged corresponding to the brake lever 11 and the brake pedal 12, respectively, and whether or not these are operated by the driver, that is, whether or not the front wheel FW or the rear wheel RW is being braked. The detection signal shown is output to the brake ECU 22.

  In the brake hydraulic pressure control device 1 configured as described above, for example, during normal braking in which ABS control or the like is not executed, a control voltage for driving the pressure reducing control valves 15 and 19 and the motor 16 is not applied from the brake ECU 22. Thus, the W / C pressure corresponding to the operation amount of the brake lever 11 and the brake pedal 12 is generated in each of the W / Cs 13 and 18. As a result, a braking force corresponding to the brake lever 11 and the brake pedal 12 is generated on the front wheel FW and the rear wheel RW.

  Further, during ABS control, a control voltage for driving the decompression control valves 15 and 19 and the motor 16 is applied from the brake ECU 22 as necessary, and the decompression control valves 15 and 19 are driven according to the applied voltage. At the same time, the motor 16 is driven. As a result, the pipelines A and D and the reservoirs 14 and 18 are brought into communication with each other through the pipelines B and E, the W / C pressure generated in each of the W / Cs 13 and 18 is reduced, and wheel slip is suppressed. This makes it possible to avoid wheel lock.

  As described above, the brake fluid pressure control device 1 for a motorcycle shown in the present embodiment is configured. Next, the vehicle speed calculation process executed by the brake fluid pressure control device 1 will be described.

  FIG. 2 is a flowchart of a vehicle body speed calculation process executed by the brake ECU 22 in the brake fluid pressure control device 1 of the present embodiment. This process is executed every predetermined calculation cycle (for example, 60 ms or 80 ms) after the ignition switch is switched from the OFF state to the ON state, for example.

  First, in step 100, it is determined whether or not the wheel speed sensors 23 and 24 of the front and rear wheels FW and RW are normal. For example, when a detection signal from the wheel speed sensors 23, 24 is not input to the brake ECU 22 due to a hardware disconnection or the like, or when a diagnosis signal indicating sensor abnormality is output from the wheel speed sensors 23, 24, etc. It is determined that the wheel speed sensors 23 and 24 are abnormal.

  If an affirmative determination is made in this step, the process proceeds to step 110, where the wheel speed of the front wheel FW and the wheel speed of the rear wheel RW are obtained, and then the wheel speed ratio (A%) is calculated. Further, at this time, the estimated vehicle speed VS0 is obtained on the assumption that the detection signals input from the wheel speed sensors 23 and 24 represent an accurate wheel speed. The estimated vehicle speed VS0 here is basically obtained by the same method as the vehicle body speed SP1 and is a well-known one. For example, the wheel speed of the front wheel FW serving as a driven wheel is assumed to be the estimated vehicle speed VS0. Alternatively, the estimated vehicle speed VS0 may be assumed as the wheel speed of the rear wheel RW serving as the driving wheel or a corrected value thereof, or the estimated vehicle speed may be determined by comparing both wheel speeds of the front wheel FW and the rear wheel RW. VS0 may be obtained.

  Then, it is recognized which area the estimated vehicle speed VS0 corresponds to in advance is divided into a plurality of speed areas, and is identified as a wheel speed ratio corresponding to the recognized area. For example, as shown in the figure, if the estimated vehicle speed VS0 <50 km / h, the wheel speed ratio at that time is identified as corresponding to A1%, and 50 km / h ≦ estimated vehicle speed VS0 <100 km / h. If so, the wheel speed ratio at that time is identified as corresponding to A2%, and if 100 km / h ≦ estimated vehicle speed VS0, the wheel speed ratio at that time is identified as corresponding to A3%. The In this way, the wheel speed ratio (A%) corresponding to each speed region is identified.

  Thereafter, the process proceeds to step 120, and the wheel speed ratio (A%) obtained in step 110 is stored in a RAM or the like provided in the brake ECU 22. The wheel speed ratio (A%) stored in this way is a value that takes into account not only the wheel diameter of the front wheel FW and the rear wheel RW but also the acceleration slip of the rear wheel RW that varies according to the vehicle speed.

  In step 110 and step 120, the wheel speed ratio (A%) is repeatedly obtained every calculation cycle and stored. At this time, the wheel speed ratio (A%) may be stored every time it is obtained, but in reality, the obtained wheel speed ratio (A%) may not be accurate. For example, such a situation may occur when an accurate wheel speed cannot be obtained due to noise in the detection signals from the wheel speed sensors 23 and 24. For this reason, the wheel speed ratio (A%) assumed in a plurality of speed regions is stored in advance as a specified range, and the calculated wheel speed ratio (A%) is not stored in the case outside the specified range. It can also be.

  When the wheel speed ratio (A%) obtained only once is not reliable, the average of the wheel speed ratio (A%) for multiple times (for example, equivalent to 1 second), the mean square, etc. are obtained, You can also remember it. In this case, a method is used in which wheel speed ratios (A%) used for averaging are excluded from those outside the specified range as described above or those that are far from other wheel speed ratios (A%). You can also

  Moreover, when using the average of the wheel speed ratio (A%) for several times, etc., it is set as the form which calculates | requires and updates the average value of wheel speed ratio (A%) for every cycle by making several times into 1 cycle. If a new wheel speed ratio (A%) is obtained, the average value is calculated instead of the oldest wheel speed ratio (A%), that is, updated by a moving average. You can also

  Furthermore, when there is a large variation in the wheel speed obtained for each calculation cycle, it is possible to store a gravel road or the like as a wheel speed with poor reliability during traveling. Such a gravel road or the like can be determined by, for example, the difference between the estimated vehicle speed VS0 obtained last time and this time, that is, whether or not the vehicle body deceleration exceeds a predetermined threshold.

  Subsequently, the routine proceeds to step 130, where it is determined whether or not the stop switch 25 of the front wheel FW is ON. When the stop switch 25 of the front wheel FW is ON, it is considered that the front wheel FW is being braked. Therefore, in such a case, even if the front wheel FW is a driven wheel, it is not preferable to calculate the vehicle body speed using the wheel speed of the front wheel FW. For this reason, when a negative determination is made in this step, it is assumed that the reliability of the wheel speed of the front wheel FW is high for the first time, the process proceeds to step 140, and the vehicle body speed SP1 is determined based on the wheel speed of the front wheel FW that becomes the driven wheel Calculated. As a result, the wheel speed of the front wheel FW is used as it is as the vehicle body speed SP1.

  If an affirmative determination is made in step 130, the process proceeds to step 150, where it is determined whether or not the stop switch 26 of the rear wheel RW is ON. When the stop switch 26 of the rear wheel RW is also ON, both the wheel speed of the front wheel FW and the wheel speed of the rear wheel RW are unreliable, but the wheel speed calculation is performed using the wheel speed of the front wheel FW relatively. It is considered preferable to do so. Therefore, if an affirmative determination is made in step 150, the process proceeds to step 140, and the vehicle body speed SP1 is obtained by the same method as described above.

  Conversely, if a negative determination is made in step 150, it is determined that the wheel speed of the rear wheel RW serving as the driving wheel is more reliable than the wheel speed of the front wheel FW being braked, and the process proceeds to step 160. The vehicle body speed SP1 is calculated based on the wheel speed of the rear wheel RW serving as the drive wheel. As a result, the vehicle speed SP1 is obtained by adding the correction constant to the wheel speed of the rear wheel RW using the reciprocal of the wheel speed ratio (A%) stored in step 120 described above as a correction constant.

  On the other hand, if a negative determination is made in step 100, the process proceeds to step 170, and it is determined whether or not the wheel speed sensor 23 of the front wheel FW that is the driven wheel is normal. The determination method here is the same as in step 100. If an affirmative determination is made in this step, it means that the wheel speed sensor 23 of the front wheel FW is normal and the wheel speed sensor 24 of the rear wheel RW is abnormal. The vehicle body speed SP1 is calculated based on the wheel speed of the front wheel FW. As a result, the wheel speed of the front wheel FW is used as it is as the vehicle body speed SP1.

  Further, when a negative determination is made at step 170, the routine proceeds to step 180, where it is determined whether or not the wheel speed sensor 24 of the rear wheel RW serving as the drive wheel is normal. The determination method here is also the same as in step 100. If an affirmative determination is made in this step, it means that the wheel speed sensor 23 of the front wheel FW is abnormal and the wheel speed sensor 24 of the rear wheel RW is normal.

  In the next step 190, it is determined whether or not the learned wheel speed ratio is stored in the RAM of the brake ECU 22. At this time, if the wheel speed ratio in the corresponding speed region has already been obtained in step 110 and stored in step 120, an affirmative determination is made in this step. If not yet stored, a negative determination is made. Will be.

  If the determination in step 190 is affirmative, the process proceeds to step 200, and even if the front wheel FW is a driven wheel, it is not preferable to perform the vehicle speed calculation using the wheel speed of the front wheel FW. The vehicle body speed calculation is performed using the wheel speed of the rear wheel RW serving as the drive wheel. As a result, the vehicle speed SP1 is obtained by adding the correction constant to the wheel speed of the rear wheel RW using the reciprocal of the wheel speed ratio (A%) stored in step 120 described above as a correction constant.

  On the other hand, if a negative determination is made in step 190, the process proceeds to step 210. In this case, since the wheel speed ratio in the corresponding speed region is not yet stored, the default value (A0%) stored in the ROM of the brake ECU 22 in advance is used, and this is used as the driving wheel. The vehicle body speed SP1 is calculated by integrating the wheel speed of the wheel RW.

  Note that the default value (A0%) here is stored in advance in the ROM for each of a plurality of speed regions.

  On the other hand, if a negative determination is made in step 180, the process proceeds to step 220. In this case, since the wheel speed sensors 23 and 24 of both the front wheel FW and the rear wheel RW are both abnormal, it is possible to obtain the accurate vehicle speed SP1 using the wheel speed obtained from these detection signals. Can not. For this reason, in this case, the calculation of the vehicle body speed SP1 is impossible (double failure).

  As described above, the vehicle body speed calculation process by the brake fluid pressure control device 1 of the present embodiment is completed. Note that the steps shown in FIG. 2 correspond to means for executing various processes in the brake ECU 22. Specifically, the portion that executes the processing of steps 110 and 120 is the wheel speed ratio storage means, the portion that executes the processing of step 130 is the front wheel braking determination means, and the portion that executes the processing of steps 140, 160, 200, and 210. Corresponds to the vehicle body speed calculation means, and the portion executing the processing of step 150 corresponds to the rear wheel braking determination means.

  Thus, according to the brake fluid pressure control apparatus 1 of the present embodiment, the wheel speed ratio (A%) when the wheel speeds of the front wheel FW and the rear wheel RW are normally obtained for each of a plurality of speed regions is stored. In addition, when the vehicle body speed SP1 is obtained using the wheel speed of the rear wheel RW serving as the drive wheel, the vehicle body speed calculation is performed based on the wheel speed ratio (A%).

  That is, the acceleration slip of the rear wheel RW varies according to the vehicle speed. For example, the acceleration slip of the rear wheel RW increases as the vehicle speed increases. Therefore, the wheel speed ratio represented simply by the wheel diameters of the front wheel FW and the rear wheel RW is The acceleration slip which fluctuates according to the speed is not taken into consideration at all. However, when the wheel speed ratio (A%) is stored for each of a plurality of speed regions as in the present embodiment, even if the acceleration slip of the rear wheel RW varies according to the vehicle speed, it is taken into consideration. The entered wheel speed ratio (A%) can be stored.

  Therefore, when determining the vehicle body speed SP1 using the wheel speed of the rear wheel RW serving as the driving wheel, if the wheel speed ratio (A%) stored for each of the plurality of speed regions as described above is used, an accurate vehicle body is obtained. The speed SP1 can be obtained. As a result, it is possible to accurately execute the brake fluid pressure control such as the ABS control based on the accurate vehicle speed SP1.

(Other embodiments)
Although the case where the vehicle body speed calculation device is provided in the brake ECU 22 has been described in the above embodiment, the present invention can be similarly applied to the case where the vehicle body speed calculation device is provided in another ECU. For example, the present invention can be applied to a case where the vehicle body speed SP1 obtained by the vehicle body speed calculation device is used as it is for the display of the speed meter as in a meter ECU. In this case, detection signals of the wheel speed sensors 23 and 24 and the stop switches 25 and 26 are input to the meter ECU, and the vehicle body speed calculation is performed by the meter ECU by the same method as in the above embodiment. In this way, it is possible to obtain an accurate vehicle speed SP1 by the vehicle speed calculation device, and therefore it is possible to display an accurate speed with a speed meter.

  In the above embodiment, as shown in FIG. 1, it is also possible to transmit data on the vehicle speed obtained by the brake ECU 22 to other ECUs through the in-vehicle LAN or the like, and display the vehicle speed on the speed meter 30.

  Furthermore, in the above embodiment, as an example of a method for storing the wheel speed ratio in association with each estimated vehicle speed, an example is given in which the wheel speed ratio is stored so as to be one fixed value in each of a plurality of speed regions. It is also possible to store the obtained estimated vehicle speed and wheel speed ratio in a one-to-one relationship without partitioning into a plurality of speed regions.

  Further, the wheel speed ratio associated with each estimated vehicle speed can be changed linearly with respect to the estimated vehicle speed, and stored as a value that increases as the estimated vehicle speed increases. Thus, if the wheel speed ratio is linearly changed according to the estimated vehicle speed, it is possible to prevent the vehicle body speed from changing stepwise at the speed at which the plurality of speed regions are switched.

1 is a diagram showing an overall configuration of a brake fluid pressure control device 1 for a motorcycle equipped with a vehicle body speed calculation device according to a first embodiment of the present invention. 2 is a flowchart of a vehicle body speed calculation process executed by a brake ECU 22 of the brake fluid pressure control device 1 shown in FIG.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 1 ... Brake fluid pressure control apparatus, 11 ... Brake lever, 12 ... Brake pedal, 13, 18 ... W / C, 14, 20 ... Reservoir, 15, 19 ... Depressurization control valve, 16 ... Motor, 17, 21 ... Pump, DESCRIPTION OF SYMBOLS 23 ... Wheel speed sensor (wheel speed sensor for front wheels) 24 ... Wheel speed sensor (wheel speed sensor for rear wheels), 25 ... Stop switch, 26 ... Stop switch, A to F ... Pipe line, FW ... Front wheel, RW ... Rear wheel.

Claims (10)

Receiving detection signals from the front wheel speed sensor (23) and the rear wheel speed sensor (24) provided for the front wheel (FW) as a driven wheel and the rear wheel (RW) as a driving wheel, The wheel speed of the front wheel (FW) and the wheel speed of the rear wheel (RW) are obtained, and the vehicle body speed (SP1) is determined based on the wheel speed of the front wheel (FW) and the wheel speed of the rear wheel (RW). A vehicle body speed calculation device for a motorcycle for performing a calculation,
When both the front wheel speed sensor (23) and the rear wheel speed sensor (24) are normal, at least one of the wheel speed of the front wheel (FW) and the wheel speed of the rear wheel (RW) Based on this, an estimated vehicle speed (VS0) is obtained, and a wheel speed ratio that is a ratio of a wheel speed of the front wheel (FW) to a wheel speed of the rear wheel (RW) is obtained, and is associated with the estimated vehicle speed (VS0). Wheel speed ratio storage means (110, 120) for storing the wheel speed ratio;
The estimated vehicle speed (VS0) is obtained based on the wheel speed of the rear wheel (RW), and stored in the wheel speed ratio storage means (110, 120) as corresponding to the obtained estimated vehicle speed (VS0). Vehicle speed calculating means (140, 160, 200, 210) for calculating the vehicle speed (SP1) by correcting the wheel speed of the rear wheel (RW) using the wheel speed ratio. A vehicle body speed calculation device characterized by that. The wheel speed ratio storage means (110, 120) determines whether or not to use the calculated wheel speed ratio based on the vehicle body deceleration determined from the estimated vehicle speed (VS0). The vehicle body speed calculation device according to claim 1. The wheel speed ratio storage means (110, 120) sets a range assumed as the wheel speed ratio corresponding to the estimated vehicle speed (VS0) as a specified range, and the obtained wheel speed ratio is the specified range. 3. The vehicle body speed calculation according to claim 1, wherein it is determined whether to use the obtained wheel speed ratio as a memory based on whether the wheel speed ratio is within a range or outside the specified range. apparatus. The wheel speed ratio storage means (110, 120) is configured to store the wheel speed ratio by dividing it into a plurality of speed regions, and the estimated vehicle speed (VS0) is stored in any of the plurality of speed regions. 4. The vehicle body speed calculation device according to claim 1, wherein it is determined whether the vehicle falls within a region, and the wheel speed ratio is stored in association with the determined region. Based on a detection signal from a front wheel stop switch (25) for detecting that a front wheel brake operating member (11) for generating a braking force for the front wheel (FW) is operated, the front wheel brake Front wheel braking determination means (130) for determining whether or not the operating member (11) is operated;
Based on a detection signal from a rear wheel stop switch (26) for detecting that a rear wheel brake operation member (12) for generating a braking force for the rear wheel (RW) is operated, Rear wheel braking determination means (150) for determining whether or not the rear wheel brake operation member (12) is operated,
When both the front wheel speed sensor (23) and the rear wheel speed sensor (24) are normal, the front wheel brake operating member (11) is operated by the front wheel braking determination means (130). When it is determined that the vehicle body speed is calculated, the vehicle body speed calculation means (140, 160, 200, 210) uses the wheel speed ratio stored in the wheel speed ratio storage means (110, 120) to The vehicle body speed calculation device according to any one of claims 1 to 4, wherein the vehicle body speed (SP1) is calculated by correcting a wheel speed of (RW). When both the front wheel speed sensor (23) and the rear wheel speed sensor (24) are normal, the front wheel brake operating member (11) is operated by the front wheel braking determination means (130). If it is determined by the rear wheel braking determination means (150) that the rear wheel brake operation member (12) is being operated, the vehicle body speed calculation means (140, 160, 200, 210) does not use the wheel speed ratio stored in the wheel speed ratio storage means (110, 120), but uses the wheel speed of the front wheel (FW) to determine the vehicle body speed (SP1). 6. The vehicle body speed calculation device according to claim 5, wherein the calculation is performed. When the front wheel speed sensor (23) is normal and the rear wheel speed sensor (24) is abnormal, the vehicle body speed calculation means (140, 160, 200, 210) The vehicle body speed (SP1) is calculated using a wheel speed of the front wheel (FW) without using the wheel speed ratio stored in the wheel speed ratio storage means (110, 120). The vehicle body speed calculation device according to any one of 1 to 6. When the front wheel speed sensor (23) is abnormal and the rear wheel speed sensor (24) is normal, the vehicle body speed calculation means (140, 160, 200, 210) It is determined whether or not the wheel speed ratio is already stored in the wheel speed ratio storage means (110, 120), and if it is stored, the wheel speed ratio storage means (110, 120) stored in the wheel speed ratio storage means (110, 120). The vehicle body speed (SP1) is calculated by correcting the wheel speed of the rear wheel (RW) using the wheel speed ratio, and if not yet stored, the wheel speed ratio storage means (110, 120). The vehicle body speed (SP1) is calculated by correcting the wheel speed of the rear wheel (RW) using the default value of the wheel speed ratio stored in advance in the vehicle. 7 Izu Vehicle speed calculation apparatus according to one or. The wheel speed ratio storage means (110, 120) stores a value such that the wheel speed ratio increases linearly as the estimated vehicle speed (VS0) increases. The vehicle body speed calculation device according to one. 10. The vehicle body speed (SP1) calculated by the vehicle body speed calculation means (140, 160, 200, 210) is output to a vehicle speed meter (30) to display a vehicle speed. The vehicle body speed calculation device according to any one of the above.

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