JP2006327231A - Electronically controlled hydraulic brake system - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an electronically controlled hydraulic brake system structured so that a brake fluid accumulated in an accumulator is controlled to a hydraulic pressure complying with the operation of a brake operating member by a hydraulic valve device controlled electronically and supplied to a wheel cylinder, capable of suppressing the brake fluid consumption of the accumulator in case needless pumping operation is applied to the brake operation member. <P>SOLUTION: Needless pumping operation is sensed by a needless pumping operation sensing routine (S18), and the hysteresis characteristic between the boosted condition of the wheel cylinder pressure and the decompressed condition is increased from normal (S22). Supplying the brake fluid to the wheel cylinder in association with the pumping operation is suppressed, and the consumption of the brake fluid by the accumulator can be suppressed. Consumption of the brake fluid can be suppressed also by arranging so that the wheel cylinder pressure is held according to sensing of unnecessary pumping operation. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to an electronic control fluid of a type in which the brake fluid stored in the accumulator is controlled to a fluid pressure according to the operation of the brake operation member by controlling the fluid pressure control valve device by the electronic control device and supplied to the wheel cylinder. The present invention relates to a pressure brake system, and particularly relates to suppression of wasteful consumption of brake fluid stored in an accumulator.

Various patent documents describe suppressing useless energy consumption in a brake system for a vehicle. For example, in Patent Document 1 below, in an electronically controlled hydraulic brake system, when a pumping operation in which a brake pedal stepping operation and a loosening operation are repeated while the vehicle is stopped is performed, the wheel cylinder fluid is controlled regardless of the depression force of the brake pedal. It is described that energy saving is achieved by suppressing the upper limit of the pressure to the limit hydraulic pressure. Further, in Patent Document 2, in an electronically controlled hydraulic brake system, energy consumption can be reduced by limiting the upper limit of the braking force to a predetermined reference braking force regardless of the depression force of the brake pedal while the vehicle is stopped. It is described that it is planned.
Further, in Patent Document 3, in an electronically controlled hydraulic brake system having a hydraulic control cylinder operated by an electric motor, when the hydraulic pressure of the wheel cylinder is maintained, the hydraulic chamber behind the hydraulic control cylinder is provided. It is described that by maintaining the hydraulic pressure, it is unnecessary to supply current to the electric motor, and the power consumption of the electric motor is reduced.
In Patent Document 4, when a vehicle is decelerated, the kinetic energy of the vehicle is recovered as a hydraulic pressure of an accumulator by a hydraulic motor / pump, and the vehicle speed is set in a brake energy regeneration device that uses the hydraulic pressure to accelerate the vehicle. In the region below the set vehicle speed, it is described that the operation of the brake energy regeneration device is stopped and the normal brake mode in which the air brake is operated is set to improve the durability of the hydraulic system including the hydraulic motor and pump.
JP 2000-177555 A Japanese Patent Laid-Open No. 2001-18769 Japanese Patent Laid-Open No. 2002-255021 Japanese Patent Publication No. 7-64250

  In view of the above circumstances, the present invention has been made with the object of obtaining an electronically controlled hydraulic brake system that can better suppress the waste of accumulator brake fluid due to unnecessary pumping operation than before. It is.

  An electronic control fluid of the type in which the brake fluid stored in the accumulator is supplied to the wheel cylinder by controlling the hydraulic pressure control valve device by the electronic control device to a hydraulic pressure corresponding to the operation of the brake operation member. In a pressure brake system, the electronic control device is solved by including a brake fluid consumption suppression unit that suppresses the consumption of brake fluid in the accumulator when the brake operation member is unnecessarily pumped in a state below the set vehicle speed. Is done.

  In the pumping operation, a brake operation member such as a brake pedal is repeatedly operated in a direction of operation performed to bring the brake into an action state and a loosening operation performed in order to loosen the action of the brake. In a pressure brake system, a large amount of brake fluid is consumed. This is because the brake fluid stored at high pressure in the accumulator is repeatedly supplied to the wheel cylinder and discharged to the reservoir. However, not all pumping operations are useless. In order to appropriately control the running of the vehicle, a pumping operation may be necessary. On the other hand, it is rarely necessary to perform a pumping operation during low-speed traveling or when the vehicle is stopped, and what is performed at this time is usually useless. According to the present invention, wasteful brake fluid consumption due to unnecessary pumping operation is suppressed better than before.

Aspects of the Invention

  In the following, the invention that is claimed to be claimable in the present application (hereinafter referred to as “claimable invention”. The claimable invention is at least the “present invention” to the invention described in the claims. Some aspects of the present invention, including subordinate concept inventions of the present invention, superordinate concepts of the present invention, or inventions of different concepts) will be illustrated and described. As with the claims, each aspect is divided into sections, each section is numbered, and is described in a form that cites the numbers of other sections as necessary. This is for the purpose of facilitating the understanding of the claimable invention, and is not intended to limit the combinations of the constituent elements constituting the claimable invention to those described in the following sections. In other words, the claimable invention should be construed in consideration of the description accompanying each section, the description of the embodiments, etc., and as long as the interpretation is followed, another aspect is added to the form of each section. In addition, an aspect in which constituent elements are deleted from the aspect of each item can be an aspect of the claimable invention.

  In each of the following items, item (1) corresponds to item 1, item (2) and item (3) are combined in item 2, item (5) in item 3, The (6) term corresponds to claim 4 and the (11) term corresponds to claim 5, respectively.

(1) Electronically controlled hydraulic pressure in which the brake fluid stored in the accumulator is supplied to the wheel cylinder by controlling the hydraulic pressure control valve device by the electronic control device to a hydraulic pressure according to the operation of the brake operating member. A brake system,
The electronic control device includes a brake fluid consumption suppression unit that suppresses consumption of brake fluid of the accumulator when the brake operation member is unnecessarily pumped in a state of a set vehicle speed or less. Control hydraulic brake system.
(2) The brake fluid consumption suppression unit includes a useless pumping operation detection unit that detects that the pumping operation of the brake operation member is a useless pumping operation that is not necessary for braking the vehicle. Electronically controlled hydraulic brake system.
(3) The useless pumping operation detection unit is
A pumping operation detector for detecting a pumping operation of the brake operation member;
After the pumping operation is detected by the pumping operation detector, when at least one of the conditions that the vehicle deceleration is equal to or lower than the set deceleration and the pumping operation is detected again by the pumping operation detector is satisfied The electronically controlled hydraulic brake system according to item (2), further including: a useless pumping operation determination unit that determines that the useless pumping operation has been performed.
When the pumping operation is performed but the subsequent vehicle deceleration is small, or when the pumping operation is frequently performed, it is appropriate that the pumping operation is useless.
(4) The brake fluid consumption suppression unit includes a warning unit that warns the driver to stop the unnecessary pumping operation when the unnecessary pumping operation detection unit detects the unnecessary pumping operation. The electronically controlled hydraulic brake system described in (3).
When the useless pumping operation detection unit detects useless pumping operation, it is desirable to warn the driver to stop the pumping operation. The warning can be performed by at least one of display on the display, lighting of the lamp, and operation of the buzzer. However, it is particularly effective to give a warning to the effect that “pumping operation causes useless energy consumption and should be avoided as much as possible” by voice.
In addition to the item (4), the inventions in the items (5) to (13) include the requirements described in the item (1), for example, “in a state below the set vehicle speed” and “uselessly”. It is also possible to implement in a mode excluding at least one of the requirements.
(5) When the brake fluid consumption suppression unit detects the unnecessary pumping operation, the hydraulic pressure control valve device increases the wheel cylinder pressure, which is the hydraulic pressure of the wheel cylinder, when the unnecessary pumping operation detection unit detects the unnecessary pumping operation. The electronically controlled hydraulic brake system according to (2) or (3), further including a hysteresis characteristic increasing unit that increases a hysteresis characteristic between the state and the reduced pressure state more than usual.
The hydraulic brake system usually has a certain hysteresis characteristic in the change of the wheel cylinder pressure, and the electronically controlled hydraulic brake system intentionally has a hysteresis characteristic for the purpose of facilitating the brake operation. May be granted. If this hysteresis characteristic is increased when detecting unnecessary pumping operation, the brake fluid is actually supplied to the wheel cylinder for the same pumping operation and the amount discharged is reduced, so the consumption of brake fluid in the accumulator is suppressed. Is done. Depending on the magnitude of the hysteresis, it is possible to cause almost no brake fluid to flow in and out of the wheel cylinder due to the pumping operation. However, if it is necessary to actually increase the braking force, the hydraulic pressure of the wheel cylinder can be increased if the brake operating member is operated strongly, and in the unlikely event that the unnecessary pumping operation is detected erroneously. It is desirable to ensure that the vehicle can be braked sufficiently even in the event that the In that case, when the unnecessary pumping operation detection unit detects the unnecessary pumping operation, the brake fluid consumption suppression unit has a hysteresis characteristic between the increased pressure state and the reduced pressure state of the wheel cylinder pressure. The size selected from the range in which the hydraulic pressure of the wheel cylinder can be increased by operating the brake operating member that is larger than normal and exceeds the hysteresis characteristics (within the range of operating force planned in the design). It is only necessary to include a hysteresis characteristic increasing portion that increases the frequency.
If the hysteresis characteristic becomes larger than usual, the relationship between the operation of the brake operating member and the deceleration generated accordingly changes, so the hysteresis characteristic increasing part can also play the role of the warning part described above. .
(6) The brake fluid consumption suppression unit
When the useless pumping operation is detected by the useless pumping operation detection unit, the useless pumping causes the hydraulic pressure control valve device to maintain the wheel cylinder pressure that is the hydraulic pressure of the wheel cylinder regardless of the loosening operation of the brake operation member. An operation-compatible hydraulic pressure holding unit;
During the holding of the hydraulic pressure by the useless pumping operation compatible hydraulic holding unit, the temperature of the driving start intention detecting unit for detecting the driver's intention to start the vehicle and the temperature of the hydraulic pressure control valve device has risen to the allowable temperature rise limit. And a hydraulic pressure holding release unit for releasing the hydraulic pressure holding state of the hydraulic pressure control valve device according to detection by at least one of the allowable limit temperature rise detecting unit for detecting Or the electronically controlled hydraulic brake system according to any one of (4).
If the wheel cylinder pressure is maintained according to the detection of the unnecessary pumping operation, the brake fluid is prevented from entering and exiting the wheel cylinder due to the pumping operation, and wasteful consumption of the brake fluid of the accumulator can be suppressed particularly well. . It is appropriate that the hydraulic pressure retention is canceled in response to the detection of the vehicle travel start intention of the driver by the travel start intention detection unit. Also, if the hydraulic control valve device needs to keep supplying current while maintaining the hydraulic pressure, such as a pressure reducing valve that reduces the hydraulic pressure of the wheel cylinder, it may overheat. There is. Therefore, it is desirable to provide a permissible limit temperature rise detection unit so that the hydraulic pressure holding is released when it is detected that the temperature of the fluid pressure control valve device has risen to the temperature rise permissible limit. It should be noted that “detecting that the temperature of the hydraulic pressure control valve device has risen to the allowable temperature rise limit” is not essential to actually detect the temperature of the hydraulic pressure control valve device. An increase to the allowable temperature rise limit may be detected indirectly, for example, by detecting the time and estimating the temperature from the duration.
(7) When the brake fluid consumption suppression unit is operated in the brake acting direction of the brake operation member while the wheel cylinder pressure is being held by the unnecessary pumping operation-compatible hydraulic pressure holding unit, the operation is performed. If it requires a wheel cylinder pressure lower than the hydraulic pressure during holding, the hydraulic pressure holding is continued, and if it requires a wheel cylinder pressure higher than the holding hydraulic pressure, the hydraulic pressure control valve device is provided with a wheel cylinder. The electronically controlled hydraulic brake system according to item (6), including a pressure increase request responding unit that increases pressure.
Even when the hydraulic pressure is maintained according to the detection of the unnecessary pumping operation, it is not always necessary to increase the braking force. Therefore, it is desirable that the pressure increase corresponding to the pressure increase request is performed even while the hydraulic pressure is being maintained.
(8) The hydraulic pressure control valve device includes a normally open pressure reducing valve that needs to continue supplying current to maintain the wheel cylinder pressure,
The brake fluid consumption suppression unit
While the vehicle is stopped, a stop-while-closed maintaining unit that keeps the normally open pressure reducing valve closed regardless of the loosening operation of the brake operation member;
A temperature increase allowable limit corresponding closed maintenance release unit that releases the normally open pressure reducing valve closed when the temperature of the normally open pressure reducing valve rises to a temperature increase allowable limit during the closed maintenance by the stop during the closed maintenance unit; The electronically controlled hydraulic brake system according to item (1).
While avoiding overheating of the normally open pressure reducing valve, wasteful consumption of the bleky liquid of the accumulator can be suppressed.
(9) Based on the closed maintenance time in which the temperature rise allowable limit corresponding closed maintenance release unit detects the temperature rise of the normally open pressure reducing valve to the temperature rise allowable limit based on the closed maintenance time of the normally open pressure reducing valve The electronically controlled hydraulic brake system according to item (8), including a temperature rise allowable limit detection unit.
The temperature increase permissible limit closed maintenance release part includes a temperature sensor that detects the temperature of the normally open pressure reducing valve, and when the detected temperature of the temperature sensor reaches the set temperature, the normally open pressure reducing valve is kept closed. It is also possible. However, the temperature increase of the normally open valve is closely related to the closed maintenance time (current supply duration), and it is possible to release the closed maintenance based on the closed maintenance time. In this case, the temperature sensor can be omitted.
The allowable limit temperature rise detection unit in the above (6) also detects the temperature rise up to the temperature rise allowable limit based on the duration of holding the hydraulic pressure, similar to the closed maintenance time-based temperature rise allowable limit detection unit in this section. Can be.
(10) When the operation of the brake operation member in the braking action direction is performed while the wheel cylinder pressure is being maintained by maintaining the normally open pressure reducing valve closed by the stop-while-closed maintaining unit, the operation is If it requires a wheel cylinder pressure lower than the holding hydraulic pressure by keeping the open pressure reducing valve closed, the hydraulic pressure holding unit is continued, and if it requires a wheel cylinder pressure higher than the holding hydraulic pressure, the hydraulic pressure control valve The electronically controlled hydraulic brake system according to item (8) or (9), wherein the device includes a pressure increase request corresponding unit that increases the wheel cylinder pressure.
(11) The electronically controlled hydraulic brake system is
An electronic control mode in which the wheel cylinder is operated by the control of the hydraulic control valve device of the brake fluid of the accumulator;
The brake fluid consumption suppressing unit is selectively operable in a manual mode in which the wheel cylinder is operated by the hydraulic pressure of a master cylinder that generates hydraulic pressure based on the operating force of the brake operating member. ,
A required braking force small detection unit for detecting that the magnitude of the required braking force is less than or equal to the set braking force;
The electronically controlled hydraulic brake system according to any one of (1) to (10), further comprising: a manual mode switching unit that switches from the electronic control mode to the manual mode in response to detection by the required braking force small detection unit. .
If the electronically controlled hydraulic brake system has a manual mode, after switching to the manual mode, the wheel cylinder will be actuated by the brake fluid supplied from the master cylinder, so a pumping operation will be performed. However, the accumulator brake fluid is not consumed. However, the generated braking force in the manual mode is usually smaller than that in the electronic control mode. In that case, the required braking force is less than the set braking force by the required braking force small detection unit. It is desirable that switching to the manual mode is performed when the error is detected. Further, in order to avoid a sudden change in the brake acting force and the reaction force applied to the brake operation member accompanying the switching to the manual mode, it is desirable that the switch is performed at a time when the operation of the brake operation member is released.
Note that “switch to manual mode in response to detection of small required braking force detection unit” must be switched to manual mode whenever “detection of small necessary braking force detection unit” is performed. However, the switching may be performed only when other requirements are satisfied, such as when the power supply voltage drops below the set value.
(12) The electronically controlled hydraulic brake system according to (11), wherein the small necessary braking force detection unit includes a flat land stop detection unit that detects that the vehicle is stopped on a flat ground.
(13) The hydraulic pressure control valve device supplies the brake fluid of the accumulator to the wheel cylinder to increase the hydraulic pressure of the wheel cylinder, and causes the brake fluid of the wheel cylinder to flow out to the low pressure portion. And a pressure reducing valve for reducing the hydraulic pressure of the wheel cylinder, and both the pressure increasing valve and the pressure reducing valve continuously change the hydraulic pressure difference between the upstream side and the downstream side according to the change of the supply current. The electronically controlled hydraulic brake system according to any one of (1) to (12).

  Hereinafter, embodiments of the claimable invention will be described with reference to the drawings. In addition to the following examples, the claimable invention can be practiced in various modifications based on the knowledge of those skilled in the art, including the aspects described in the above [Aspect of the Invention] section. .

An embodiment of an electronically controlled hydraulic brake system is shown in FIG. The brake system includes a brake pedal 10 as a brake operation member, a master cylinder 12, a power hydraulic pressure source 14 that is operated by power, hydraulic brakes 16 to 19 provided on wheels located on the left and right and front and rear, respectively. .
The hydraulic brakes 16 to 19 include wheel cylinders 22 to 25, respectively, and are operated by the hydraulic pressure of the wheel cylinders 22 to 25 (referred to as wheel cylinder pressure). In this embodiment, the brake is a disc brake that presses a brake pad as a friction material held by a non-rotating body against the brake discs 22b to 25b rotating together with the wheels by hydraulic pressure.

The master cylinder 12 includes two pressure pistons, and the hydraulic pressure corresponding to the operation force is applied to the pressure chambers in front of the two pressure pistons by the driver operating the brake pedal 10. Be generated. The left and right front wheel cylinders 22 and 23 are connected to the two pressurizing chambers of the master cylinder 12 via master passages 26 and 27, respectively. Master shutoff valves 29 and 30 are provided in the middle of the master passages 26 and 27, respectively. The master shut-off valves 29 and 30 are normally open electromagnetic on-off valves.
In addition, four wheel cylinders 22 to 25 are connected to the power hydraulic pressure source 14 via a pump passage 36. The wheel cylinders 22 to 25 are supplied with hydraulic pressure from the power hydraulic pressure source 14 while being disconnected from the master cylinder 12, and the hydraulic brakes 16 to 19 are operated. The hydraulic pressure of the wheel cylinders 22 to 25 is controlled by a hydraulic pressure control valve device 38.
As described above, the wheel cylinders 22 to 25 for the left and right front and rear wheels are operable by the hydraulic pressure of the power hydraulic pressure source 14, while the wheel cylinders 22 and 23 for the left and right front wheels are hydraulic pressures of the master cylinder 12 (master (Also called pressure).

  The power hydraulic pressure source 14 includes a pump device 69 including a pump 66 and a pump motor 68 that drives the pump 66. The suction side of the pump 66 is connected to a master reservoir 72 (hereinafter abbreviated as “reservoir 72”) via a suction passage 70, and an accumulator 74 is connected to the discharge side. The hydraulic fluid in the reservoir 72 is pumped up by the pump 66, supplied to the accumulator 74, and stored in a pressurized state. Further, the discharge side portion and the suction side portion 73 of the pump 66 are connected by a relief passage 76 as a return passage. A relief valve 78 is provided in the relief passage 76. The relief valve 78 switches from the closed state to the open state when the hydraulic pressure (discharge pressure) on the discharge side of the pump 66, which is the high pressure side, exceeds the set pressure. These pump device 69, accumulator 74, relief valve 78 and the like constitute the power hydraulic pressure source 14.

The hydraulic pressure control valve device 38 is an electromagnetic pressure provided in the pressure reducing passage 104 that directly connects the pressure increasing linear valves 100 to 103 as the electromagnetic control valve provided in the pump passage 36 and the wheel cylinders 22 to 25 and the reservoir 72. Pressure reduction linear valves 110 to 113 as control valves. The hydraulic pressures of the wheel cylinders 22 to 25 can be controlled independently by controlling the pressure increasing linear valves 100 to 103 and the pressure reducing linear valves 110 to 113, respectively.
The pressure-increasing linear valves 100 to 103 and the pressure-reducing linear valves 110 and 111 are normally closed valves that are in a closed state while no current is supplied to the coil 120, but the pressure-reducing linear valves 112 and 113 on the rear wheel side are coils. While the current is not supplied to 122, it is a normally open valve that is open.

  A stroke simulator device 180 is provided in the master passage 26. The stroke simulator device 180 includes a stroke simulator 182 and a normally closed simulator opening / closing valve 184. The opening / closing of the simulator opening / closing valve 184 allows the stroke simulator 182 to allow the pressurization piston of the master cylinder 12 to advance and a brake pedal. 10 is switched between an operation state in which an operation reaction force is applied to 10 and a non-operation state in which the operation reaction is not performed.

  The hydraulic brakes 16 to 19 are controlled based on a command from the brake ECU 300 as shown in FIG. The brake ECU 300 is an electronic control device mainly including a computer, and includes an execution unit 302, a storage unit 304, an input / output unit 306, and the like. A stroke sensor 312, a master pressure sensor 314, a wheel cylinder pressure sensor 316, a wheel speed sensor 318, a hydraulic pressure source hydraulic pressure sensor 320, a vehicle speed calculation unit 322, an accelerator sensor 324, and the like are connected to the input / output unit 306. , Coils 120 of pressure-increasing linear valves 100 to 103 and pressure-reducing linear valves 110 and 111, coils 122 of pressure-reducing linear valves 112 and 113, coils of master shut-off valves 29 and 30, simulator control valve 184, pump motor 68 and warning device 326 and the like are connected via a drive circuit (not shown). The vehicle speed computing device 322 computes wheel speed, wheel deceleration, vehicle speed (vehicle traveling speed), vehicle deceleration, and the like based on the output of the wheel speed sensor 318, and supplies it to the brake ECU 300. The accelerator sensor 324 detects an operation of an accelerator pedal as an acceleration operation member.

The brake system operates in electronic control mode during normal braking. When the master shut-off valves 29 and 30 are closed, the wheel cylinders 22 to 25 are shut off from the master cylinder 12, and the hydraulic brakes 16 to 19 are operated by the hydraulic pressure of the power hydraulic pressure source 14. Based on at least one of the operation stroke detected by the stroke sensor 312 and the master pressure detected by the master pressure sensor 314, the driver's required braking value (required wheel cylinder pressure in this embodiment) is obtained. In the case where the braking request value is obtained based on both the operation stroke and the master pressure, for example, the braking request value is obtained based on the operation stroke and the master pressure, respectively. The ratio of the required braking value determined based on the master pressure is large (for example, 100%), and thereafter the ratio of the required braking value determined based on the master pressure gradually increases (for example, increases to 100%). The braking request value can be added, or the larger one of the braking request value determined based on the operation stroke and the braking request value determined based on the master pressure can be selected. . Then, based on the braking request value, a control command value (in this embodiment, a command current which is a command value of a current supplied to the coils 120 and 122 of the pressure-increasing linear valves 100 to 103 and the pressure-reducing linear valves 110 to 113) is determined. Then, the current supplied to the coils 120 and 122 is controlled so that the actual wheel cylinder pressure approaches the command hydraulic pressure corresponding to the command current.
In the above description, for the sake of simplification, it is assumed that the required brake cylinder value is the required wheel cylinder pressure based on at least one of the operation stroke and the master pressure. It is also possible to obtain the required wheel cylinder pressure. In the latter case, a deceleration that accurately corresponds to the driver's operation of the brake pedal 10 is realized.

The normal braking control described above is performed by repeatedly executing the normal control program stored in the storage unit 304 every minute time while the power source of the brake ECU 300 is ON. This normal control program is the same as the normal program except that hysteresis characteristics are provided as shown in FIG. 2 in the transition from pressure increase to pressure reduction and from pressure reduction to pressure increase. That is, in S1, it is determined whether or not the operation of the brake pedal 10 by the driver indicates a holding request. If the determination result is YES, holding control is performed immediately in S2, but the pressure increase in S3 In the case where the determination result of whether or not it indicates a request is YES (when pressure increase is required) or NO (when pressure reduction is required), the pressure increase request value is the hysteresis value in S4. The pressure increase control in S5 is not started until P _IH or higher, and the pressure reduction control in S7 is not started until the pressure reduction required value (represented by a negative value) becomes equal to or lower than the hysteresis value P _{DH in} S6. It is. The hysteresis values P _IH and P _DH may be set to 0 during normal braking.

  The storage unit 304 stores a brake fluid consumption suppression program represented by the flowcharts of FIGS. 3 to 5 together with the normal control program. The brake fluid consumption suppression program increases the hysteresis characteristics of the pressure increase / decrease of the wheel cylinders 22 to 25 when it is detected that an unnecessary pumping operation has been performed, thereby increasing the wheel cylinders 22 to 22. 25, the consumption of the brake fluid in the accumulator 74 is suppressed, and is repeatedly executed every minute time while the power source of the brake ECU is in the ON state as in the normal control program. .

First, in S10 of FIG. 3, it is determined whether or not the vehicle speed is lower than the set vehicle speed. If the determination result is NO, "small hysteresis" is set in S12, and useless pumping operation detection is performed in S14. The flag F _UP is turned OFF, and in S15, various flags, count values, timers, and the like, which are changed during the execution of this program, are returned to the initial state. “Low hysteresis” is a term used in comparison with “high hysteresis” in which the hysteresis characteristic is increased to suppress the brake fluid consumption, and means a normal wheel cylinder pressure control state. The useless pumping operation detection flag F _UP is a flag indicating that useless pumping operation has been detected, and in a state in which the use pumping operation is turned off, “high hysteresis” wheel cylinder pressure control is not performed. That is, in this embodiment, the brake fluid consumption is not suppressed unless the vehicle speed is lower than the set vehicle speed.

If the determination result in S10 is YES, it is determined in S16 whether or not the useless pumping operation detection flag _FUP is ON. The useless pumping operation detection flag _FUP is not shown in the initial setting. Since it is OFF, the determination result is initially NO. Therefore, the useless pumping operation detection routine of S18 is executed. This routine will be described later. If the determination result in S20 is NO, one execution of this routine ends. If YES, “large hysteresis” is set in S22. The hysteresis values P _IH and P _DH are made larger than those during normal braking. Therefore, assuming that the pumping operation in which the pedal force is increased or decreased as shown in FIG. 6 is performed, the wheel cylinder pressure shown in the lower stage is not changed until the unnecessary pumping operation is detected and the “high hysteresis” is set. The change corresponding to the change in the pedaling force shown in the upper stage (in the case of “small hysteresis”, both the hysteresis values P _IH and P _DH can be set to 0, and FIG. 6 shows this case for simplification. However, after the setting of “large hysteresis”, the wheel cylinder pressure is not increased or decreased for the pedal force change corresponding to the increased hysteresis, and the accumulator 74 is reduced by the amount of increase in pressure. Reduces brake fluid consumption. Assuming an extreme case where the pumping operation is performed only within the hysteresis range, the wheel cylinder pressure is not increased or decreased at all.

  After execution of S22, the warning device 326 is activated in S24. A warning “Please do as much as possible because pumping causes unnecessary energy consumption” is given by voice. In response to this warning, if the driver stops the pumping operation that was being performed, or if it tries to avoid unnecessary pumping operation thereafter, consumption of the brake fluid of the waste accumulator 74 is reduced accordingly, The amount of operation of the pump motor 68 for supplying the brake fluid is reduced, the durability of the power hydraulic pressure source is improved, and unnecessary noise generation and energy consumption are suppressed.

After the useless pumping operation is detected in the useless pumping operation detection routine and the useless pumping operation detection flag _FUP is turned ON, the determination result in S16 is YES, and it is determined whether or not the suppression of the brake fluid consumption should be finished. Is done. In the present embodiment, it is determined in S26 whether or not the vehicle has been accelerated based on the output of the accelerator sensor 324, and in S28, it is determined whether or not the deceleration is large. Whether or not the deceleration is equal to or greater than the set deceleration is determined based on the information from the calculation device 322 such as the vehicle speed. If any of the determination results in S26 and S28 is YES, in S30, “ “Small Hysteresis” is set, the useless pumping operation detection flag F _UP is turned OFF in S32, and the initial state return process similar to that in S15 is performed in S34. The brake fluid consumption suppression is terminated. When both determination results of S26 and S28 are NO, S30 to S34 are skipped, and the brake fluid consumption suppression is continued.

FIG. 4 shows details of the useless pumping operation detection routine. This routine, the pumping operations detection routine of S40, S42, S44, and whether the determination flow or the detected pumping operation S48~58 is useless, useless pumping operation detection flag F _UP setting step of S46 Including. Although details of the pumping operation detection routine S40 will be described later, whether or not a pumping operation is detected in S42 is determined after execution of this routine based on whether or not the pumping operation detection flag _FP is ON. If the determination result is YES, it is determined in S44 whether or not the deceleration is small depending on whether or not the vehicle deceleration is equal to or less than the set deceleration. If the determination result is YES, the unnecessary pumping operation is performed in S46. The detection flag F _UP is set to ON, and in S47, those other than the useless pumping operation detection flag F _UP are returned to the initial state. This is because when the deceleration is small even though the pumping operation is performed, it is appropriate that the pumping operation is useless.

If the determination result in S44 is NO, it is determined in S48 to S54 whether or not the current pumping operation detection is a re-detection. First, the First pumping operation detection flag F _F at S48 whether ON is determined, initially the determination result is NO, and the pumping operation detection flag F _P is turned OFF in S50, the in S52 single pumping operation detection flag F _F is the ON, first timer is started in S54. When the first pumping operation is detected, the first pumping operation detection flag _FF is turned ON, and the measurement of the elapsed time thereafter is started. Therefore, after the pumping operation is detected for the second time and the determination result in S42 is YES, the determination result is YES when S48 is executed. In S56, the second pumping operation is detected after the first pumping operation is detected. whether the elapsed time T ₁ of the up pumping operation detection is within the set time T _1S is determined, the determination result is YES, useless pumping operation detection flag F _uP in S46 is turned ON. The fact that the pumping operations are performed again within a short time indicates that these pumping operations are useless.

On the other hand, if the determination result is NO, the pumping operation detected this time is not a pumping operation performed again shortly after the previous pumping operation, but an independent pumping operation, that is, the first pumping operation. It is reasonable to do. Therefore, a return process is performed in S58. Pumping operation detection flag FP is ON, with the first single pumping operation detection flag F _F is the OFF, first timer is the is stopped the cleared and counting.

Details of the pumping operation detection routine S40 are shown in FIG. First, in S60, it is determined whether the pumping operation detection flag F _P is ON, if the decision result is YES, the implementation of S62~120 is skipped, the execution of one of the pumping operation detecting routine finish. If the determination result in S60 is NO, in S62, the driver's braking request value is acquired based on information from the stroke sensor 312 and the master pressure sensor 314. Then, in S64, the difference between the previous braking request value and the current braking request value is calculated. Based on the calculation result, it is determined in S66, 68 which one of holding, increasing pressure, and decreasing pressure is requested by the driver. The If the difference is a relatively small value between the pressure increase threshold value and the pressure decrease threshold value, it is determined that it is required not to change the wheel cylinder pressure (referred to as a holding request), and the pressure increase threshold value or more is determined. If it is, it will be determined that pressure increase is required, and if it is below the pressure reduction threshold, it will be determined that pressure reduction is required. The pressure increase threshold value and the pressure decrease threshold value are such sizes that it is guaranteed that a holding request is always detected between the pressure increase request and the pressure decrease request, no matter how fast the brake operation is performed. In spite of the driver's request for holding, the driver may inadvertently increase or decrease pressure due to noise included in the output signal of the stroke sensor 312 or the master pressure sensor 314, slight pedaling force or stroke fluctuation. The size is set such that no determination is made.

In S66, when the holding request is determined to have been made, in S70, whether pressure increase request flag F _I is the ON is determined, the determination result is YES, increase in S72 The pressure request count N _I is incremented by 1, and F _I is turned OFF in S74. Subsequently, in S76, based on the count value of the second timer, it is determined whether it is timed or not, and if it is not timed, the second timer is started. If S70 of the determination result is NO in S80, it is determined whether the pressure reduction request flag F _D is turned ON is when the determination result is YES S82~88 is executed, in the case of NO S82 to 88 are skipped. Since S82 to S88 are the same as S72 to 78 described above, the description thereof will be omitted, but the second timer is used for the one that has been made first, regardless of whether the pressure increase request or the pressure reduction request is made first. depending and of being allowed to start with, whether the pressure increase request count N _I within the set time T _2S and decompression request count N _D becomes equal to or greater than the preset number, respectively, whether it has become both a twice or more in the shown example or it is determined (S90,92), if the result of the determination is YES, the pumping operation detection flag F _P is turned oN in S94, in S95, the pressure increase request flag F _I, reduced pressure request flag F _R, but OFF Then, the recovery process such as clearing the second timer, the pressure increase request counter (N _I ), the pressure decrease request counter (N _D ), etc. is performed. Even when the determination result in S90 is NO, a similar return process is performed in S96.

If the determination result in S66 is NO, it is determined in S68 whether or not a pressure increase request has been made. If the determination result is YES, it is determined in S102 whether or not a previous pressure increase request has been made. Is done. If the result of the determination is NO, that is, if the holding request has just changed to the pressure increase request, the braking request value, that is, the required wheel cylinder pressure is stored in S104. When the determination of S102 is performed for the second time, the determination result is YES, so the required pressure increase value is calculated in S106. The difference between the current demand wheel cylinder pressure and the demand wheel cylinder pressure stored in S104 is obtained. Then, in S108, it is determined whether the request increase value is larger than the set pressure increase value is, if the determination result is to YES, pressure increase request flag F _I is turned ON in the S110. Only when a relatively large depressing that may say depressing as part of the pumping operation of the brake pedal 10 is performed, it is the pressure increase request flag F _I is to ON.

If the determination results of S66 and S68 are both NO, this means that a pressure reduction request has been made, and S112 to S120 are executed. These S112 to S120 are substantially the same as S102 to S110, although there is a difference between the pressure increase and the pressure reduction, and thus the description thereof is omitted.
As described above, a relatively large stepping operation and a loosening operation are detected. Based on the detection results, in steps S70 to 92, as described above, a relatively large stepping operation and a loosening operation are performed within the set time T _S. If the bets were both performed twice or more, it is determined that the pumping operation has been performed, it is the pumping operation detection flag F _P is turned oN in S94. Even if a relatively large stepping operation or loosening operation is repeatedly performed, if the time interval between them is large, the determination result in S90 is NO before the determination result in S92 is YES, and the return process in S96 since is made, does not pumping operation detection flag F _P is turned ON.

  As is apparent from the above description, in this embodiment, the portion of the brake ECU 300 that executes the pumping operation detection routine of FIG. 5 constitutes the pumping operation detection unit, and the portion that executes S44 to 58 of FIG. An unnecessary pumping operation determination unit is configured, and an unnecessary pumping operation detection unit is configured by the pumping operation detection unit and the unnecessary pumping operation determination unit. Further, the portion that executes S20 and S22 in FIG. 3 constitutes a hysteresis characteristic increasing portion, and in combination with the unnecessary pumping operation detecting portion and the portion that determines whether or not the vehicle speed is less than or equal to the S10 set vehicle speed, In the state, when the brake operation member is unnecessarily pumped, the brake fluid consumption suppression unit is configured to suppress consumption of the brake fluid of the accumulator.

FIG. 7 shows a flowchart of a brake fluid consumption suppression program executed in the brake ECU 300 of the electronically controlled hydraulic brake system which is another embodiment. This program suppresses wasteful consumption of brake fluid in the accumulator 74 by maintaining the wheel cylinder pressure when a useless pumping operation is detected.
First, in S130, but useless pumping operation detection flag F _UP whether there is a ON is determined, initially the determination result is NO, S132～136 is executed. Of these steps, S130, 134 and 136 are the same as S10, 18 and 20 in the above embodiment. However, the wheel cylinder pressure is maintained only when the vehicle is stopped. Whether or not the vehicle is stopped is determined in S132, and only after S134 is executed only when the determination result is YES. If the determination in S132 is NO, an initial state return process is performed in S175. When the vehicle is started during the execution after S134, all the vehicles that have been changed from the initial state during the execution after S134 are returned to the initial state.

Unnecessary pumping operation in the above S134 is detected, if the judgment result of S136 is YES, in S138, but whether the hold flag F _H is turned ON is determined, initially the determination result is NO because it is, holding command at S140 is issued, the hold flag F _H at S142 is a turned ON, the third timer is started in S144. When the normally open linear pressure reducing valves 112 and 113 are kept in an energized state in order to hold the holding maintenance allowable time, that is, the wheel cylinder pressure of the wheel cylinders 24 and 25, the third timer This is for monitoring the passage of time until the temperature rises to the allowable temperature rise limit. The length of the holding maintenance allowable time is shorter as the current supplied to the coil 122 is larger, that is, as the wheel cylinder pressure to be held is larger. In S144, when the holding command is issued. A holding maintenance allowable time corresponding to the size of the wheel cylinder pressure is set. Thereafter, each time this program is executed once, in S146, the content of the third timer is decremented by one, and the remaining time of the allowable holding time is measured.

Once the useless pumping operation detection flag F _UP is once turned ON, the determination result of S130 executed thereafter is YES, and it is determined whether or not the holding of the wheel cylinder pressure should be released. This determination is performed as follows in the illustrated example. First, in S150, it is determined whether or not a start operation has been performed, such as whether or not an accelerator pedal operation has been performed based on the output of the accelerator sensor 324, and if the determination result is NO. In S152, it is determined whether or not the remaining time of the allowable holding maintenance time has decreased to 0 or less. If the determination result in S152 is also NO, S136 and subsequent steps are executed. If the determination result in any one of S150 and S152 is YES, a holding release process is performed in S154. The holding of the wheel cylinder pressure is released, the unnecessary pumping operation detection flag F _UP , the holding flag F _H , the additional pressure increasing flag F _{A and the} like are turned OFF, the third timer is reset to 0, and unnecessary pumping operation During execution of the detection routine S134, various things different from the initial state are restored to the initial state.

While the wheel cylinder pressure is maintained as described above, it is monitored in S160 and later whether or not an additional pressure increase request has been made by the driver. First, in S160, it is determined whether or not the additional pressure increasing flag F _A is ON. Initially, the determination result is NO, and in S162, the driver's requested hydraulic pressure is the wheel cylinder pressure that is being held. depending on whether or not larger than the hydraulic pressure, it is determined whether the additional pressure increase required by the driver, if the determination result is YES, the additional pressure increase flag F _a is oN at S164, increasing pressure command row in S166 Is called. It should be noted that this increase during pressurization also holding flag F _H is maintained in the ON state, S146 is executed. The determination result in S160 after the additional pressure increase flag F _A is turned ON is YES, and in S168, it is waited that the actual hydraulic pressure as the actual wheel cylinder pressure becomes equal to or higher than the required hydraulic pressure. In step S170, the additional pressure increase flag F _A is turned OFF, a holding command is issued in step S172, and the third timer is restarted in step S174. As described above, since the allowable holding time varies depending on the wheel cylinder pressure to be maintained, the allowable holding time remaining after the completion of the additional pressure increase is determined with respect to the wheel cylinder pressure after the additional pressure increase. Is calculated, and the result of the calculation is reset in the third timer.

As is clear from the above description, in this embodiment, if a useless pumping operation is detected, holding of the wheel cylinder pressure at that time is started, and if the driver's required hydraulic pressure increases during the holding, When the wheel cylinder pressure is increased and held, and the driver performs a starting operation or the coil 122 of the normally open pressure reducing linear valves 112 and 113 is overheated, Current supply to 122 is stopped, and the holding of the wheel cylinder pressure is released.
That is, once an unnecessary pumping operation is detected, even if the pumping operation is further performed, the brake fluid is not supplied to the wheel cylinders 22 to 25, and the brake fluid of the accumulator 74 is not consumed. However, if the requested wheel cylinder pressure exceeds the holding wheel cylinder pressure during the pumping operation, the excess pressure is increased, and the driver's request to increase the braking force is satisfied.

  In the present embodiment, the portion of the brake ECU 300 that executes S138 to 146 and S160 to 174 constitutes a useless pumping operation-compatible hydraulic pressure holding portion, and the portion that executes S150 is intended to start traveling together with the accelerator sensor 324. The part which comprises a detection part and performs S144,146,152,174 etc. comprises the allowable limit temperature rise detection part, and the part which performs S154 comprises the hydraulic pressure holding | maintenance cancellation | release part.

  FIG. 8 shows a flowchart of a brake fluid consumption suppression program executed in the brake ECU 300 of the electronically controlled hydraulic brake system which is still another embodiment. This program is designed so that when the brake pedal 10 is operated while the vehicle is stopped, the wheel cylinder pressure is maintained regardless of whether or not the unnecessary pumping operation is performed. Even so, the brake fluid of the accumulator 74 is prevented from being wasted.

First, in S180, but whether the hold flag F _H is turned ON is determined, initially the determination result is NO, S182 and subsequent steps are executed. In S182, it is determined whether or not the vehicle is stopped. If the determination result is NO, the initial state return process in S184 is performed in the same manner as S175 in FIG. 7, and one execution of this program is completed. However, if YES, it is determined in S186 whether or not the brake pedal 10 is being operated. If the determination result is YES, in S188, the wheel cylinder pressure is automatically controlled based on the depression force of the brake pedal 10, and S180 to 190 are repeatedly executed to make the wheel cylinder pressure constant, that is, the depression force Is expected to become constant. Once the depression force is fixed, the determination result is YES in S190, the holding of the wheel cylinder pressure is commanded in S192, the holding flag F _H is turned ON in S194, the timer is started in S196. These S192 to 196 are the same as S140 to 144 in the embodiment of FIG. If the holding flag F _H is turned ON, the determination result in S180 is YES, and after the count value of the timer is decremented by 1 in S198, S200 to S204 are executed. These S200 to S204 are the same as S150 to 154 in FIG. Further, S160 and subsequent steps executed after S196 or S202 are the same as S160 to S174 in the above-described embodiment, and therefore, the same reference numerals are given and description thereof is omitted.

In the present embodiment, when the brake pedal 10 is operated while the vehicle is stopped, the wheel cylinder pressure is maintained at a magnitude corresponding to the depression force of the brake pedal 10, and when the depression force of the brake pedal 10 is increased, the pressure is increased. Is done. However, even if the pedal force is reduced, the wheel cylinder pressure is not reduced. Therefore, even if the pumping operation is performed while the vehicle is stopped, the wheel cylinder pressure is only increased to a level corresponding to the maximum pedaling force in the pumping operation, and the brake fluid of the accumulator 74 is repeatedly applied to the wheel cylinders 22 to 25. It is not supplied and discharged, and wasteful brake fluid consumption is satisfactorily suppressed. Further, when the start operation is performed or when the holding maintenance allowable time has passed, the holding release processing is performed, and the start of the vehicle is prevented, or the coils 122 of the normally open decompression linear valves 112 and 113 are overheated. This is also avoided well.
The part of the brake ECU 300 that executes the brake fluid consumption suppression program constitutes a brake fluid consumption suppression unit.

Still another brake fluid consumption suppression program is shown in FIG. This program is the same as the above embodiment in that the wheel cylinder pressure is maintained while the vehicle is stopped, but the wheel cylinder pressure that is maintained is used to maintain the vehicle in a stopped state regardless of the depression force of the brake pedal 10. It is different in that it is necessary and sufficient. Accordingly, the same steps are denoted by the same reference numerals, description thereof is omitted, and only different steps are described.
Is parked, if the judgment result of S182 becomes YES, and in S210, but the required pressure calculation flag F _C whether ON is determined, a initially determination result is NO, the S212, Stop conditions are acquired. For example, the inclination angle of the road surface and the vehicle weight are acquired. In this case, instead of the warning device 326 in FIG. 1, the inclination angle sensor 330 shown in FIG. Four load sensors 332 are provided. The vehicle weight is obtained from the sum of the detection values of the four load sensors 332. Then, in S214, based on the vehicle weight and the tilt angle, and is necessary to maintain the stop state sufficient required fluid pressure is calculated a wheel cylinder pressure, in S216, the required fluid pressure operation flag F _C Turned on.

Subsequently, in S218, it is determined whether or not the actual hydraulic pressure, which is the actual wheel cylinder pressure, is equal to the required hydraulic pressure. However, since the determination result is normally NO, the actual hydraulic pressure is required in S220. A hydraulic pressure control routine for equalizing the hydraulic pressure is executed. Since this hydraulic pressure control routine is the same as a normal hydraulic pressure control program, description thereof is omitted. After the desired pressure operation flag F _C is turned ON, the determination result of S210 is to become YES, S212~216 is skipped, S220 etc. is repeated. Eventually, the determination result in S218 is YES, and S192 to S196 are executed. However, these steps are the same as those in the embodiment of FIG. Also, since after the hold flag F _H is turned ON in the S194, since the determination result of S180 is YES, S198～S204 but is executed, the steps are the same as the embodiment of FIG. 8, described Is omitted.

In this embodiment, during stopping, the wheel cylinder pressure is necessary and sufficient to maintain the stopped state regardless of whether the pumping operation is performed and the magnitude of the depression force of the brake pedal 10. Therefore, even if a pumping operation is performed, the pumping operation does not affect the control of the wheel cylinder pressure. Since the brake fluid of the accumulator 74 is repeatedly supplied to the wheel cylinders 22 to 25 and is not discharged, wasteful consumption of brake fluid is satisfactorily suppressed. The operational effects when the start operation is performed or when the holding maintenance allowable time has elapsed are the same as those in the above-described embodiment.
The part of the brake ECU 300 that executes the brake fluid consumption suppression program constitutes a brake fluid consumption suppression unit.

Yet another brake fluid consumption suppression program is shown in FIG. This program is an electronically controlled hydraulic brake system when the brake pedal 10 is released while the required hydraulic pressure, which is a wheel cylinder pressure necessary and sufficient to maintain the stopped state, is released while the vehicle is stopped. By switching to the manual mode, the brake fluid consumption is suppressed.
First, in S230, it is determined whether or not the vehicle is stopped. If the determination result is YES, it is determined in S231 whether or not the manual mode is set. Since the manual mode is canceled in the initial setting (not shown) (the electronic control mode is set), the determination result is initially NO, and the stopping condition is acquired in S232. For example, the inclination angle of the road surface is detected by the inclination angle sensor 330. Subsequently, in S234, it is determined whether or not the required hydraulic pressure is small by determining whether or not the road surface is flat with no inclination. If the determination result is YES, it is determined in S236 whether or not the operation stroke of the brake pedal 10 is 0. If the determination result is YES, the manual mode is set in S238. If the determination result in S236 is NO, S230 to 236 are repeatedly executed to wait for the brake pedal 10 to be released, and if released, the manual mode is set.

When the manual mode is set, the master shut-off valves 29 and 30 in FIG. 1 are brought into communication with the master cylinder 12 and the wheel cylinders 22 and 23, and the brake ECU 300 sets the hydraulic control valve device 38 in FIG. Normal state shown in Therefore, the electronic control mode control using the brake fluid of the accumulator 74 is not performed, and the brake fluid of the accumulator 74 is not wasted even if a pumping operation is performed.
Further, if the vehicle is started to travel, the determination result in S230 is NO, and the manual mode is canceled in S240. Therefore, the wheel cylinder pressure is controlled in the electronic control mode, and sufficient braking force is guaranteed. Is done.
A portion of the brake ECU 300 that executes S230, 232, and 234 constitutes a small required braking force detection unit, and a portion that executes S238 constitutes a manual mode switching unit. The switching unit constitutes a brake fluid consumption suppression unit.

1 is a circuit diagram showing an electronically controlled hydraulic brake system that is an embodiment of the claimable invention; FIG. It is a flowchart showing a part of normal control program performed in brake ECU of the said brake system. It is an example of the flowchart showing the brake fluid consumption control program executed in the brake ECU. It is a flowchart which shows the one part detail of the said flowchart. It is a flowchart which shows the further one part detail of the flowchart which shows the said one part detail. It is a graph for demonstrating brake fluid consumption suppression by the said brake fluid consumption suppression program. It is a flowchart showing the brake fluid consumption control program performed in brake ECU of the electronically controlled hydraulic brake system which is another Example. It is a flowchart showing the brake fluid consumption control program performed in brake ECU of the electronically controlled hydraulic brake system which is another Example. It is a flowchart showing the brake fluid consumption control program performed in brake ECU of the electronically controlled hydraulic brake system which is another Example. It is a block diagram which shows a part of electronically controlled hydraulic brake system of the Example of the said FIG. It is a flowchart showing the brake fluid consumption control program performed in brake ECU of the electronically controlled hydraulic brake system which is another Example.

Explanation of symbols

10: Brake pedal 12: Master cylinder 14: Power hydraulic pressure source 16-19: Hydraulic brake 22-25: Wheel cylinder 38: Hydraulic pressure control valve device 66: Pump 68: Pump motor 70: Suction passage 72: Master reservoir 74 : Accumulator 100 to 103: Pressure increasing linear valve 110 to 113: Pressure reducing linear valve 120, 122: Coil 300: Brake ECU 312: Stroke sensor 314: Master pressure sensor 316: Wheel cylinder pressure sensor 318: Wheel speed sensor 320: Hydraulic pressure Source hydraulic pressure sensor 322: vehicle speed calculation device 324: accelerator sensor 326: warning device 330: tilt angle sensor 332: load sensor

Claims (5)

An electronically controlled hydraulic brake system that supplies the brake fluid stored in the accumulator to the wheel cylinder by controlling the hydraulic pressure according to the operation of the brake operation member by controlling the hydraulic pressure control valve device by the electronic control device. There,
The electronic control device includes a brake fluid consumption suppression unit that suppresses consumption of brake fluid of the accumulator when the brake operation member is unnecessarily pumped in a state of a set vehicle speed or less. Control hydraulic brake system. The brake fluid consumption suppression unit includes a useless pumping operation detection unit, the useless pumping operation detection unit,
A pumping operation detector for detecting a pumping operation of the brake operation member;
After the pumping operation is detected by the pumping operation detector, when at least one of the conditions that the vehicle deceleration is equal to or lower than the set deceleration and the pumping operation is detected again by the pumping operation detector is satisfied The electronically controlled hydraulic brake system according to claim 1, further comprising: a useless pumping operation determination unit that determines that the pumping operation of the brake operation member is a useless pumping operation that is not necessary for braking the vehicle.   When the brake fluid consumption suppression unit detects the unnecessary pumping operation, the hydraulic pressure control valve device, when the unnecessary pumping operation detection unit detects the increased pressure state and reduced pressure of the wheel cylinder pressure, which is the hydraulic pressure of the wheel cylinder. The electronically controlled hydraulic brake system according to claim 2, further comprising a hysteresis characteristic increasing unit that increases a hysteresis characteristic between the state and the normal state. The brake fluid consumption suppression unit is
When the useless pumping operation is detected by the useless pumping operation detection unit, the useless pumping causes the hydraulic pressure control valve device to maintain the wheel cylinder pressure that is the hydraulic pressure of the wheel cylinder regardless of the loosening operation of the brake operation member. An operation-compatible hydraulic pressure holding unit;
During the holding of the hydraulic pressure by the useless pumping operation compatible hydraulic holding unit, the temperature of the driving start intention detecting unit for detecting the driver's intention to start the vehicle and the temperature of the hydraulic pressure control valve device has risen to the allowable temperature rise limit. And a hydraulic pressure holding release unit for releasing the hydraulic pressure holding state of the hydraulic pressure control valve device according to detection by at least one of the allowable limit temperature rise detecting unit for detecting Electronically controlled hydraulic brake system as described. The electronically controlled hydraulic brake system
An electronic control mode in which the wheel cylinder is operated by the control of the hydraulic control valve device of the brake fluid of the accumulator;
The brake fluid consumption suppressing unit is selectively operable in a manual mode in which the wheel cylinder is operated by a hydraulic pressure of a master cylinder that generates a hydraulic pressure based on an operating force of the brake operating member. ,
A required braking force small detection unit for detecting that the magnitude of the required braking force is less than or equal to the set braking force;
The electronically controlled hydraulic brake system according to any one of claims 1 to 4, further comprising: a manual mode switching unit that switches from the electronic control mode to the manual mode in accordance with detection by the small necessary braking force detection unit.

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