JP2016097859A - Brake control device for bar handle vehicle - Google Patents

Abstract

PROBLEM TO BE SOLVED: To suppress cost increase by estimating a vehicle body speed for control based on a wheel speed from a wheel speed sensor provided in either one of a front wheel and a rear wheel.SOLUTION: A brake control device for a bar handle vehicle (a controller 100) is a brake control device for a bar handle vehicle capable of performing ABS control to either one of wheels of the front wheel and the rear wheel. The brake control device for a bar handle vehicle includes: vehicle body speed calculation means 110 for calculating a vehicle body speed based on a wheel speed of one wheel; a correction-use-vehicle-body-speed calculation means 120 for calculating a vehicle body speed for correction by limiting a change amount of a wheel speed of the one wheel to a first limit value; determination means 140 for determining whether correction of the vehicle body speed is needed or not; and correction means 130 for using the vehicle body speed and the correction-use vehicle body speed selectively according to a determination result of the determination means 140 as the vehicle body speed used for ABS control .SELECTED DRAWING: Figure 2

Description

  The present invention relates to a bar-handle vehicle brake control device capable of executing anti-lock brake control (hereinafter also referred to as “ABS control”).

  Conventionally, as a bar handle vehicle brake control device for controlling the brake force of a bar handle vehicle such as a motorcycle, ABS control is executed on the front wheels and the rear wheels based on the vehicle body speed and the wheel speed. The thing is known (refer patent document 1). Specifically, in this technique, a wheel speed sensor is provided for each of the front wheel and the rear wheel, and the brake control device for the bar handle vehicle uses the wheel speed obtained from each wheel speed sensor, and more specifically, the front wheel and the rear wheel. The vehicle body speed is calculated by correcting the vehicle body speed using the wheel speed ratio.

Japanese Patent No. 4622729

  Incidentally, a bar-handle vehicle brake control device that ABS-controls only one of the front wheels and the rear wheels is also conventionally known. In this case, in order to calculate the control vehicle speed used for the ABS control, When a method such as the above-described conventional technique is used, it is necessary to provide a wheel speed sensor even on a wheel that does not perform ABS control, and there is a problem that the cost increases.

  Therefore, an object of the present invention is to suppress an increase in cost by estimating a vehicle body speed for control based on a wheel speed from a wheel speed sensor provided on only one of the front wheel and the rear wheel.

  In order to solve the above-mentioned problems, a bar handle vehicle brake control device according to the present invention is a bar handle vehicle brake control device capable of executing anti-lock brake control on one of front wheels and rear wheels. The vehicle body speed calculating means for calculating the vehicle body speed based on the wheel speed of the one wheel, and the correction vehicle body speed is calculated by limiting the amount of change in the wheel speed of the one wheel by the first limit value. As a correction vehicle body speed calculation means, a determination means for determining whether or not the correction of the vehicle body speed is necessary, and a control vehicle body speed used for the antilock brake control according to the determination result of the determination means, And a correction unit that selectively uses the vehicle body speed and the correction vehicle body speed.

  According to this configuration, the vehicle body speed calculated based on the wheel speed of one of the wheels according to the determination result of the determination unit, and the correction vehicle body speed calculated separately from the vehicle body speed, Therefore, the vehicle body speed for control can be estimated well using only one wheel speed. Since the vehicle body speed for control can be estimated using only one wheel speed in this way, it is only necessary to provide the wheel speed sensor only on one wheel, and the cost increase can be suppressed.

  In the above configuration, the determination means needs to correct the vehicle body speed when the total pressure reduction amount from the pressure reduction control start to the pressure increase control start in the anti-lock brake control is equal to or greater than a predetermined threshold. Can be configured.

  For example, if the vehicle body speed is estimated to be higher than the actual vehicle body speed, the decompression may be excessively performed. If the decompression is excessively performed in this way, the control vehicle body speed is changed to the correction vehicle body. The speed can be converged by reducing the speed.

  Further, in the above-described configuration, when the road surface friction coefficient estimating means for estimating the road surface friction coefficient is provided, the vehicle body speed calculation means sets the change amount of the wheel speed to a second limit value corresponding to the road surface friction coefficient. It can be configured to calculate the vehicle body speed by limiting at.

  According to this, the vehicle body speed can be appropriately calculated according to the road surface condition where the bar handle vehicle is traveling.

  In the configuration described above, the magnitude of the first limit value can be greater than or equal to the maximum value of the magnitude of the second limit value.

  According to the present invention, since the control vehicle body speed can be estimated using only one wheel speed, it is only necessary to provide the wheel speed sensor only on one wheel, and the cost increase can be suppressed.

It is a figure showing composition of a bar handle vehicle provided with a brake control device for bar handle vehicles concerning an embodiment. It is a block diagram which shows the structure of a control part. It is a flowchart which shows operation | movement of a control part. It is a time chart which shows the change of each parameter after a road surface condition switches from a low μ road to a high μ road during ABS control.

Hereinafter, embodiments will be described in detail with reference to the drawings as appropriate.
As shown in FIG. 1, a motorcycle as an example of a bar handle vehicle according to the present embodiment includes a brake system BF for a front wheel WF, a brake system BR for a rear wheel WR, and an example of a brake control device for a bar handle vehicle. The control part 100 is provided. In the present embodiment, the front wheel WF corresponds to “one of the front wheels and the rear wheels”.

  The brake system BF includes a master cylinder MF, a hydraulic unit 10, a wheel brake 20, a pipe 30 connecting the master cylinder MF and the inlet port 10a of the hydraulic unit 10, an outlet port 10b of the hydraulic unit 10, and a wheel brake. 20 is mainly configured by a pipe 40 that connects 20 and a wheel speed sensor 51 that detects a wheel speed Vw of the front wheel WF. Further, the brake system BR mainly includes a master cylinder MR, a wheel brake 20, and a pipe 50 that connects the master cylinder MR and the wheel brake 20.

  The master cylinder MF is a device that outputs a hydraulic pressure corresponding to the amount of operation of the brake lever LF that the driver operates with the right hand, and the master cylinder MR corresponds to the amount of operation of the brake lever LR that the driver operates with the left hand. It is a device that outputs the hydraulic pressure.

  Each of the wheel brakes 20 is a wheel that generates a braking force (braking force) by pressing the brake pad against the brake rotor 21 by the brake rotor 21, a brake pad (not shown), and the hydraulic pressure output from the master cylinders MF and MR. A cylinder 23 is mainly provided.

  The hydraulic unit 10 mainly includes an inlet valve 1, a check valve 1a, an outlet valve 2, a reservoir 3, a pump 4, a suction valve 4a, a discharge valve 4b, an orifice 5a, a damper 5b, and a motor 6, and normally has an inlet port. Since the oil passage communicates from 10a to the outlet port 10b, the hydraulic pressure output from the master cylinder MF is transmitted to the wheel brake 20 of the front wheel WF.

  The inlet valve 1 is a normally-open electromagnetic valve provided between the master cylinder MF and the wheel brake 20. The inlet valve 1 is normally open, thereby allowing hydraulic pressure to be transmitted from the master cylinder MF to the wheel brake 20. Further, the inlet valve 1 is blocked by the control unit 100 when the front wheel WF is about to be locked, thereby blocking the transmission of hydraulic pressure from the master cylinder MF to the wheel brake 20.

  The outlet valve 2 is a normally closed electromagnetic valve provided between the wheel brake 20 and the reservoir 3. Although the outlet valve 2 is normally closed, the hydraulic pressure applied to the wheel brake 20 is released to the reservoir 3 by being opened by the control unit 100 when the front wheel WF is about to be locked.

  The check valve 1 a is a valve that allows only the brake fluid to flow from the wheel brake 20 side to the master cylinder MF side, and is connected in parallel to the inlet valve 1. When the hydraulic pressure input from the master cylinder MF is released, the check valve 1a allows the brake fluid to flow from the wheel brake 20 side to the master cylinder MF side even when the inlet valve 1 is closed.

  The reservoir 3 temporarily stores brake fluid that is released when the outlet valve 2 is opened. The pump 4 is provided between the reservoir 3 and the master cylinder MF, and is driven by the rotational drive of the motor 6 to suck the brake fluid stored in the reservoir 3 and return it to the master cylinder MF. The orifice 5a and the damper 5b absorb fluid pressure fluctuations.

  The hydraulic pressure unit 10 is controlled by the controller 100 so that the opening and closing states of the inlet valve 1 and the outlet valve 2 are controlled, so that the braking force, specifically, the hydraulic pressure of the wheel cylinder 23 of the front wheel WF (hereinafter referred to as “wheel cylinder” Pressure "). For example, in a normal state in which the inlet valve 1 is opened and the outlet valve 2 is closed, if the brake lever LF is operated, the hydraulic pressure of the master cylinder MF is transmitted to the wheel cylinder 23 as it is and the braking force increases. Pressure state. Further, when the inlet valve 1 is closed and the outlet valve 2 is opened, the brake fluid flows out from the wheel cylinder 23 to the reservoir 3 side, resulting in a reduced pressure state in which the braking force is reduced. Further, when both the inlet valve 1 and the outlet valve 2 are closed, the hydraulic pressure of the wheel cylinder 23 is maintained and the braking force is maintained.

  The control unit 100 is a device that executes ABS control that suppresses locking of the front wheel WF by mainly controlling the hydraulic unit 10 provided in the brake system BF of the front wheel WF. The control unit 100 includes, for example, a CPU (Central Processing Unit), a RAM (Random Access Memory), a ROM (Read Only Memory), an input / output circuit, and the like. Control is executed by performing various arithmetic processes based on programs, data, and the like stored in the program.

  As shown in FIG. 2, the control unit 100 includes a vehicle body speed calculation unit 110, a correction vehicle body speed calculation unit 120, a correction unit 130, a determination unit 140, an ABS control unit 150, and a storage unit 160. ing.

  The vehicle body speed calculation means 110 has a function of calculating the vehicle body speed Vc based on the wheel speed Vw of the front wheel WF acquired from the wheel speed sensor 51. Specifically, the vehicle body speed calculation means 110 calculates the amount of change in the wheel speed Vw by subtracting the previous value from the current value of the wheel speed Vw, and the calculated amount of change in the wheel speed Vw is a predetermined limit value G. By limiting, the vehicle body speed Vc is calculated. Specifically, the vehicle body speed calculation unit 110 determines whether or not the calculated change amount of the wheel speed Vw is smaller than the limit value G. If the change amount is smaller, the change amount of the wheel speed Vw is determined. The vehicle body speed Vc is calculated by adding the wheel speed Vw to the previous value of the wheel speed Vw and, if larger, adding the limit value G to the previous value of the wheel speed Vw.

  Here, the limit value G is a negative limit value for limiting the deceleration, and is also referred to as a road surface friction coefficient (hereinafter referred to as “road surface μ”) estimated by a road surface friction coefficient estimating unit 151 of the ABS control unit 150 described later. It is set based on. Specifically, the vehicle body speed calculation means 110 sets the limit value G to the initial value Gf when the road surface μ is not estimated, and sets the limit value G when the road surface μ is estimated. Is set to the second limit value Gμ corresponding to.

  Specifically, the second limit value Gμ is set such that the magnitude (absolute value) is larger as the road surface μ is higher and the magnitude is smaller as the road surface μ is lower. A map or calculation formula indicating the relationship between the road surface μ and the second limit value Gμ is stored in the storage means 160, and the vehicle body speed calculation means 110 uses the map or calculation formula and the road surface μ to 2 Calculate the limit value Gμ. The magnitude of the initial value Gf is set to, for example, the maximum value of the second limit value Gμ, that is, a value corresponding to the high μ road.

  When the vehicle body speed calculating unit 110 calculates the vehicle body speed Vc, the vehicle body speed calculating unit 110 outputs the calculated vehicle body speed Vc to the correcting unit 130.

  The correction body speed calculation means 120 limits the correction change amount calculated by subtracting the previous value of the correction body speed Va from the wheel speed Vw of the front wheel WF acquired from the wheel speed sensor 51 with the first limit value G1. Thus, the vehicle body speed Va for correction is calculated. Here, the first limit value G1 is a negative fixed value for limiting the deceleration, and is set to, for example, the maximum value of the second limit value Gμ, that is, a value corresponding to the high μ road. .

  Specifically, the correction vehicle body speed calculation means 120 determines whether or not the calculated correction change amount is smaller than the first limit value G1, and if so, determines the correction change amount. The correction body speed Va is calculated by adding the correction vehicle speed Va to the previous value of the correction vehicle speed Va and, if larger, adding the first limit value G1 to the previous value of the correction vehicle speed Va. When the correction body speed Va is calculated, the correction body speed calculation means 120 outputs the calculated correction body speed Va to the correction means 130. When there is no previous value of the correction vehicle body speed Va, that is, when calculation of the correction vehicle body speed Va is started (when the vehicle starts), the previous value of the correction vehicle body speed Va is zero.

  The correction means 130 normally outputs the vehicle body speed Vc output from the vehicle body speed calculation means 110 to the ABS control means 150, and when a correction signal (to be described later) is output from the determination means 140, the correction speed 130 is set to the vehicle body speed Vc. Instead, it has a function of outputting the correction vehicle speed Va output from the correction vehicle speed calculation means 120 to the ABS control means 150. Specifically, the correction means 130 determines whether the control vehicle speed V output to the ABS control means 150 is the vehicle speed Vc or the correction vehicle speed Va according to the presence or absence of a correction signal. When the correction signal is not received, the vehicle body speed Vc is substituted for the control vehicle body speed V, and when the correction signal is received, the correction vehicle body speed Va is substituted for the control vehicle body speed V.

  The determination unit 140 has a function of determining whether or not the vehicle body speed Vc needs to be corrected based on the total pressure reduction amount ΔP output from the total pressure reduction amount calculation unit 152 of the ABS control unit 150. . Specifically, the determination unit 140 determines whether or not the total decompression amount ΔP has become equal to or greater than a predetermined threshold value α. When it is determined that the total decompression amount ΔP has become equal to or greater than the predetermined threshold value α, correction is necessary. Determination is made and a correction signal indicating this is output to the correction means 130.

  The ABS control unit 150 calculates the slip amount based on the wheel speed Vw output from the wheel speed sensor 51 and the control vehicle body speed V output from the correction unit 130, and based on the slip amount, a known amount is calculated. It has a function of executing ABS control. Further, the ABS control means 150 is a road surface friction coefficient estimation means 151 for estimating the road surface μ, and a total pressure reduction amount calculation means for calculating a total pressure reduction amount ΔP from the pressure reduction control start to the pressure increase control start in the ABS control. 152.

  The road surface friction coefficient estimating means 151 has a function of estimating the road surface μ during the ABS control. Specifically, the road surface friction coefficient estimating means 151 tentatively determines that the road surface μ is appropriately large (e.g., equivalent to a high μ road) at the start of the ABS control (first decompression control), and this is determined as the road surface μ. Estimated value of Further, after starting ABS control, the road surface friction coefficient estimating means 151 estimates deceleration from the time lapse of the wheel speed Vw and estimates road surface μ from the deceleration in the second and subsequent decompression control. When the road surface friction coefficient estimating unit 151 estimates the road surface μ, the road surface friction coefficient estimating unit 151 outputs the estimated road surface μ to the vehicle body speed calculating unit 110.

  In order to calculate the total pressure reduction amount ΔP during the period from the start of the pressure reduction control to the start of the next pressure increase control, for example, the total pressure reduction amount calculation unit 152 integrates the time during which pressure was actually reduced during the period. Then, the total pressure reduction amount ΔP is calculated based on the accumulated time. Specifically, the total decompression amount calculation unit 152 calculates the total decompression amount ΔP that gradually increases during the period, and outputs the total decompression amount ΔP to the determination unit 140 each time it is calculated. Further, the total decompression amount calculation means 152 once resets the total decompression amount ΔP after the end of the period, and then newly calculates the total decompression amount ΔP from the time point when the decompression control is started again. Further, when the calculated total decompression amount ΔP is equal to or greater than the threshold value α, the total decompression amount calculating unit 152 holds the total decompression amount ΔP until the ABS control is completed.

  The storage unit 160 stores a program for causing the control unit 100 to function as each unit described above, a map or a calculation formula for calculating the second limit value Gμ, and the like.

  Next, the process for calculating the control vehicle speed V by the control unit 100 will be described in detail with reference to FIG. Specifically, the operations of the vehicle body speed calculation unit 110, the correction vehicle body speed calculation unit 120, the correction unit 130, and the determination unit 140 will be described.

  As shown in FIG. 3, the vehicle body speed calculation unit 110 and the correction vehicle body speed calculation unit 120 obtain the wheel speed Vw of the front wheel WF from the wheel speed sensor 51 provided only on the front wheel WF (S1). After step S1, the vehicle body speed calculation means 110 determines whether or not the road surface μ is estimated by the road surface friction coefficient estimation means 151 (S2).

  When it is determined in step S2 that the road surface μ has been estimated (Yes), the vehicle body speed calculation means 110 calculates the second limit value Gμ based on the road surface μ (S3), and then sets the limit value G to the first value. 2 The limit value Gμ is set (S4), and the process proceeds to step S5. When it is determined in step S2 that the road surface μ has not been estimated (No), the vehicle body speed calculation unit 110 keeps the limit value G as the initial value Gf, and proceeds to the process of step S5.

  In step S5, the vehicle body speed calculating means 110 calculates the vehicle body speed Vc based on the wheel speed Vw and the limit value G. After step S5, the correction vehicle body speed calculation means 120 calculates the correction vehicle body speed Va based on the wheel speed Vw and the first limit value G1 (S6).

  After step S6, the determination unit 140 determines whether or not the total reduced pressure ΔP is greater than or equal to the threshold value α (S7). When the total pressure reduction amount ΔP is less than the threshold value α in step S7 (No), the correction means 130 substitutes the vehicle body speed Vc for the control vehicle body speed V (S8).

  If the total pressure reduction amount ΔP is greater than or equal to the threshold value α in step S7 (Yes), the correction means 130 substitutes the correction vehicle body speed Va for the control vehicle body speed V (S9). After steps S8 and S9, the correction means 130 outputs the control vehicle body speed V to the ABS control means 150 (S10). After step S10, the vehicle body speed calculation means 110 resets the limit value G, that is, returns it to the initial value Gf, and ends this control.

Next, an example of a method for calculating the control vehicle body speed V will be described in detail with reference to FIG.
FIG. 4 is a diagram illustrating changes in parameters after the road surface state is switched from the low μ road to the high μ road during the ABS control.

  Between times t0 and t1, the road surface condition is a low μ road, the ABS control state is under pressure increase control, and the brake operation amount by the driver is constant, so that the wheel cylinder pressure is constant. It has become. When the road surface condition is switched from the low μ road to the high μ road at time t1, the wheel speed Vw of the front wheel WF gradually decreases. Thereafter, when the driver increases the brake operation amount (time t2), the wheel cylinder pressure gradually increases.

  Since the pressure reduction control is not performed between the times t0 and t1, the estimated road surface μ remains a value corresponding to the low μ road. Therefore, the vehicle body speed Vc calculated using the second limit value Gμ set based on the road surface μ is limited to a value larger than the wheel speed Vw. On the other hand, the correction vehicle body speed Va calculated using the first limit value G1 corresponding to the high μ road is calculated with substantially the same value as the wheel speed Vw. At this time, since the total pressure reduction amount ΔP is less than the threshold value α, the control vehicle body speed V is set to the vehicle body speed Vc.

  Thereafter, when the slip amount, which is the difference between the control vehicle body speed V (Vc) and the wheel speed Vw, becomes equal to or greater than a predetermined value (time t3), the control unit 100 starts the pressure reduction control. As a result, the wheel cylinder pressure gradually decreases, and the total pressure reduction amount ΔP gradually increases.

  Thereafter, when the total pressure reduction amount ΔP becomes equal to or greater than the threshold value α (time t4), the control unit 100 switches the control vehicle body speed V from the vehicle body speed Vc to the correction vehicle body speed Va. As a result, the control vehicle body speed V becomes the correction vehicle body speed Va limited by the first limit value G1 corresponding to the high μ road, and therefore has substantially the same value as the actual vehicle body speed. As a result, convergence of the reduced pressure can be achieved.

  At this time, even if the wheel speed Vw temporarily decreases, the control vehicle body speed V is set to the correction vehicle body speed Va limited by the first limit value G1 without decreasing to the wheel speed Vw. Therefore, the control vehicle body speed V can be brought close to the actual vehicle body speed. Thereafter, when the wheel speed Vw gradually recovers, the control unit 100 executes the holding control to keep the wheel cylinder pressure constant (time t4 to t5).

  Thereafter, when the wheel speed Vw follows the control vehicle body speed V (Va) (time t5), the control unit 100 gradually increases the wheel cylinder pressure by executing the pressure increase control.

According to the above, the following effects can be obtained in the present embodiment.
Normally, the vehicle body speed Vc is calculated based on the wheel speed Vw of the front wheel WF, and when the calculated vehicle body speed Vc needs to be corrected, the correction vehicle body speed Va calculated separately from the vehicle body speed Vc is used. Since the control vehicle body speed V is corrected, the control vehicle body speed V can be satisfactorily estimated using only the wheel speed Vw of the front wheel WF. Since the vehicle body speed V for control can be estimated using only the wheel speed Vw of the front wheel WF in this way, it is only necessary to provide the wheel speed sensor 51 only on the front wheel WF, and the cost increase can be suppressed.

  For example, when correcting the vehicle body speed V for control, if it is corrected so as to match the wheel speed Vw, there is a risk of overcorrection. However, according to the present embodiment, by using the vehicle body speed Va for correction, Appropriate correction can be performed so that the vehicle body speed becomes substantially the same value.

  Since the vehicle body speed Vc is calculated by limiting the change amount of the wheel speed Vw with the second limit value Gμ corresponding to the road surface μ, the vehicle body speed Vc is appropriately set according to the road surface condition where the motorcycle is traveling. Can be calculated.

  In addition, this invention is not limited to the said embodiment, It can utilize with various forms so that it may illustrate below.

  In the embodiment, the magnitude of the first limit value G1 is the maximum value of the second limit value Gμ. However, the present invention is not limited to this, and the magnitude of the first limit value is the second limit value. The value may be larger than the maximum value.

  In the above embodiment, the wheel speed sensor 51 is provided only on the front wheel WF. However, the present invention is not limited to this. For example, the wheel speed sensor may be provided only on the rear wheel.

  In the above-described embodiment, the control unit 100 (bar handle vehicle brake control device) is configured to control the hydraulic brake device using the brake fluid, but is not limited thereto. For example, the brake control device for a bar handle vehicle may be configured to control an electric brake device that generates a braking force by an electric motor without using brake fluid.

  In the embodiment, the motorcycle is exemplified as the bar handle vehicle to which the present invention is applied. However, the present invention is not limited to this. For example, the bar handle vehicle may be a motor tricycle or a buggy car.

  In the above embodiment, the brake system BR of the rear wheel WR is operated by the brake lever LR. However, the present invention is not limited to this. For example, the brake system of the rear wheel is operated by a brake pedal operated by a foot. You may comprise.

  Moreover, the brake with respect to the other wheel in which ABS control is not performed is not limited to a hydraulic brake, For example, a mechanical brake may be sufficient.

  In the above embodiment, the road surface μ is estimated based on the deceleration estimated from the time course of the wheel speed Vw. However, the present invention is not limited to this, and for example, the road surface is based on the deceleration detected by the acceleration sensor. μ may be estimated.

DESCRIPTION OF SYMBOLS 100 Control part 110 Vehicle body speed calculation means 120 Correction body speed calculation means 130 Correction means 140 Determination means

Claims (4)

A bar handle vehicle brake control device capable of executing anti-lock brake control on one of front wheels and rear wheels,
Vehicle body speed calculating means for calculating the vehicle body speed based on the wheel speed of the one wheel;
A correction body speed calculation means for calculating a correction body speed by limiting the amount of change in the wheel speed of the one wheel with a first limit value;
Determination means for determining whether correction of the vehicle body speed is necessary;
According to a determination result of the determination unit, a correction unit that selectively uses the vehicle body speed and the correction vehicle body speed as a control vehicle body speed used for the antilock brake control is provided. Brake control device for bar handle vehicles.   The determination means determines that the correction of the vehicle body speed is necessary when the total pressure reduction amount from the pressure reduction control start to the pressure increase control start in the antilock brake control is equal to or greater than a predetermined threshold value. The brake control device for a bar handle vehicle according to claim 1. A road surface friction coefficient estimating means for estimating a road surface friction coefficient;
The vehicle body speed calculation means calculates the vehicle body speed by limiting the amount of change in the wheel speed with a second limit value corresponding to the road surface friction coefficient. Brake control device for bar handle vehicles.   4. The brake control device for a bar handle vehicle according to claim 3, wherein the magnitude of the first limit value is equal to or greater than a maximum value of the magnitude of the second limit value. 5.

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