JP6457373B2 - Pressure regulating system, vehicle hydraulic brake system equipped with the pressure regulating system, and method for obtaining pressure regulating characteristics in the pressure regulating system - Google Patents

Description

  The present invention relates to a pressure regulating system for adjusting and supplying the pressure of hydraulic fluid from a high pressure source by a pressure regulator, a vehicle hydraulic brake system including the pressure regulating system, and the pressure regulating system. The present invention relates to a method for obtaining a pressure regulation characteristic which is a relationship between a current supplied to a linear valve for adjusting a pilot pressure of the pressure regulator and a pressure of hydraulic fluid supplied from the pressure regulator.

  The following patent document discloses a pressure regulating system including a pressure regulator and a pressure increasing linear valve and a pressure reducing linear valve for adjusting a pilot pressure of the pressure regulator. In this document, a hydraulic brake system for a vehicle is also disclosed in which the hydraulic fluid supplied from the pressure regulator is introduced into the master cylinder device using the pressure regulating system to generate a braking force according to the pressure of the hydraulic fluid. Has been.

JP 2013-208987 A

  The pressure regulator of the pressure regulating system disclosed in the above document is a so-called poppet valve type pressure regulator. On the other hand, it is also considered that a so-called spool valve type pressure regulator is adopted as the pressure regulator because the risk of foreign object biting is small. In simple terms, a spool valve type pressure regulator provides communication between a high pressure port connected to a high pressure source and a pressure regulation port to which regulated hydraulic fluid is supplied when the spool is located at a specific position in the movable range. When the low pressure port connected to the low pressure source and the pressure regulating port are in communication (hereinafter sometimes referred to as “depressurized state”) and the spool moves a predetermined distance from the specific position. And the pressure regulating port communicate with each other, and the communication between the low pressure port and the pressure regulating port is blocked (hereinafter sometimes referred to as “pressure-increasing state”). Due to such a structure, the spool valve type pressure regulator has a pressure regulation characteristic different from that of the poppet valve type pressure regulator. The present invention has been made in view of such circumstances, and enhances the practicality of a pressure regulation system having a spool valve pressure regulator, or adopts the pressure regulation system with enhanced practicality. Therefore, it is an object to provide a hydraulic brake system for a vehicle that is highly practical.

  In order to solve the above-described problems, a pressure regulating system according to the present invention includes the spool valve pressure regulator, an electromagnetic pressure increasing linear valve and a pressure reducing linear valve for adjusting a pilot pressure of the pressure regulator, and the linear valves. And a control device that controls the supply pressure that is the pressure of the hydraulic fluid supplied from the pressure regulator by controlling the supply current to the control device, and the control device is configured to execute supply current change control . This supply current change control is performed by a pressure increase start current that is a supply current to the pressure increasing linear valve at the start of the pressure increasing process and a pressure reduction that is a supply current to the pressure reducing linear valve at the start of the pressure reducing process. It is a control that changes at least one of the starting current depending on whether the preceding process, which is one of the pressure increasing process and the pressure reducing process performed before those processes, is a pressure increasing process or a pressure reducing process. .

  Further, the hydraulic brake system for a vehicle according to the present invention introduces the pressure adjusting system according to the present invention, a brake operation member, a brake device provided on a wheel, and hydraulic fluid supplied from the pressure regulator. A master cylinder device that pressurizes the hydraulic fluid to a pressure corresponding to the pressure of the introduced hydraulic fluid and supplies the hydraulic fluid to the brake device, and the control device of the pressure regulation system supplies the pressure increasing linear valve and the pressure reducing linear valve By controlling the supply current, the brake force generated by the brake device is controlled. That is, this is a hydraulic brake system for a vehicle in which the supply current change control is executed.

  Furthermore, the pressure regulation characteristic acquisition method of the present invention is a pressure regulation system including the spool valve type pressure regulator, in which a) the pressure increase start current at the start of the pressure increase process and the supply pressure A step of obtaining a pressure increase start characteristic that is a relationship when the preceding process is a pressure reduction process; and b) a pressure reduction start characteristic that is a relationship between the pressure reduction start current and the supply pressure at the start of the pressure reduction process. The method includes at least one of obtaining a case where the preceding process is a pressure increasing process.

  The spool valve type pressure regulator accompanies the movement of the spool for the predetermined distance in switching between the increased pressure state and the reduced pressure state. Therefore, as will be described in detail later, even if the pressure increasing process or the pressure decreasing process is to be started at the same supply pressure, the pressure increasing start current depends on whether the preceding process is a pressure increasing process or a pressure reducing process. Alternatively, the decompression start current is different. According to the pressure regulation system of the present invention, since at least one of the pressure increase start current and the pressure decrease start current is changed depending on the preceding process, the supply pressure is accurately controlled, in other words, the supply pressure is appropriately set. It becomes possible to control.

  Further, according to the vehicle hydraulic brake system of the present invention, since the above-described supply current change control is executed, the advantage obtained by the pressure regulation system of the present invention, that is, the advantage that the supply pressure can be controlled with high accuracy. It is possible to control the braking force with high accuracy.

  Furthermore, according to the pressure regulation characteristic acquisition method of the present invention, the pressure regulation characteristic in the case where the process to be started is different from the preceding process is acquired. By using the acquired pressure regulation characteristic, the pressure regulation system of the present invention can be easily constructed.

Aspects of the Invention

  In the following, some aspects of the invention that can be claimed in the present application (hereinafter sometimes referred to as “claimable invention”) will be exemplified 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 merely for the purpose of facilitating the understanding of the claimable inventions, and is not intended to limit the combinations of the constituent elements constituting those inventions 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 some constituent elements are deleted from the aspect of each item can be an aspect of the claimable invention.

  The following item (0) is an aspect showing the configuration of the pressure regulation system that is the premise of the claimable invention. In each of the following items, the items (1) to (6) are claims 1 to 6. It corresponds to. The (11) term corresponds to claim 7, the (21) term in claim 8, the (22) term in claim 9, the (25) term in claim 10, the (26) terms and ( The combination of item (28) corresponds to item (11).

(0) (a) a high pressure port for receiving hydraulic fluid from a high pressure source, (b) a low pressure port for discharging hydraulic fluid to a low pressure source, and (c) for supplying pressure-controlled hydraulic fluid A pressure regulating port, (d) a pressure regulating chamber into which the pressure-adjusted hydraulic fluid is introduced, (e) a pilot pressure chamber into which hydraulic fluid serving as a pilot pressure is introduced, and (f) the pressure regulating chamber. And a spool that is biased to the other end side by the pressure of the hydraulic fluid in the pilot pressure chamber, and the spool is located at a specific position on one end side of the movable range. In the case where the low pressure port and the pressure regulating port are communicated with each other, the communication between the high pressure port and the pressure regulating port is blocked, and the spool moves a predetermined distance from the specific position to the other end side in the movable range. The communication between the low pressure port and the pressure regulating port And said high pressure port and the pressure regulating port and the spool valve mechanism and a comprise constituted a pressure regulator for communicating while disconnection,
An electromagnetic pressure increasing linear valve and a pressure reducing linear valve connected to the pilot pressure chamber in order to adjust the pressure of the hydraulic fluid in the pilot pressure chamber;
By controlling the supply current to the pressure-increasing linear valve in the pressure-increasing process and the current to be supplied to the pressure-decreasing linear valve in the pressure-decreasing process, the pilot pressure is adjusted, and the hydraulic fluid supplied from the pressure regulator And a control device for adjusting the supply pressure, which is the pressure of the gas, to a pressure corresponding to the adjusted pilot pressure.

  The pressure regulator in this aspect is what is called a spool valve type pressure regulator, and the hydraulic fluid supplied from the pressure regulator is regulated using the balance between the pilot pressure and the supply pressure. That is, the supply pressure is adjusted to a pressure corresponding to the pilot pressure by moving the spool in the movable range. When the spool is in the specific position, the supply pressure is lowered, i.e., in a "depressurized state", and when the spool is moved from the specific position to the other end side by a predetermined distance, the supply pressure is increased, “Pressurized state”. In the state where the spool has moved from the specific position to the other end side but the moving distance does not reach the predetermined distance, the pressure adjusting port does not communicate with either the high pressure port or the low pressure port. In this state, the supply pressure is maintained, that is, the “pressure maintenance state”.

In addition, if it supplements about control of an electromagnetic linear valve, for example, in the "pressure increase process" which raises supply pressure, by controlling the supply current to a pressure increase linear valve by making a pressure reduction linear valve into a closed state, On the other hand, in the “depressurization process” in which the supply pressure is lowered, the supply pressure is controlled by maintaining the supply pressure constant by controlling the supply current to the pressure-reduction linear valve by closing the pressure-increasing linear valve. In the “pressure maintaining process”, for example, both the pressure increasing linear valve and the pressure reducing linear valve may be closed.
(1) The control device
At least one of a pressure increase start current that is a supply current to the pressure increasing linear valve at the start of the pressure increasing process and a pressure decrease start current that is a supply current to the pressure reducing linear valve at the start of the pressure reducing process. , Configured to execute supply current change control that changes depending on whether the preceding process, which is one of the pressure increasing process and the pressure reducing process performed before those processes, is a pressure increasing process or a pressure reducing process The pressure regulating system according to item (0).

  As described above, in the spool valve type pressure regulator, the pressure increasing state and the pressure reducing state are realized with the pressure maintaining state in between in relation to the moving position of the spool. Therefore, whether or not the spool has moved by the predetermined distance in the case of returning from the pressure-increasing state to the pressure-increasing state after being once maintained in the pressure-maintaining state and in the case of shifting from the pressure-increasing state to the pressure-reducing state through the pressure maintaining state Therefore, even if the same supply pressure is to be realized, the pilot pressure corresponding to the supply pressure is different. More specifically, when a predetermined distance of movement is involved, the hydraulic fluid for that movement must be supplied to and discharged from the pilot pressure chamber, the frictional force received by the spool during the movement, and the spool on one end side This is due to a difference in the urging force of the return spring when there is a return spring that is biased in accordance with the predetermined distance. In other words, even if the same supply current is supplied to the pressure-increasing linear valve and the pressure-reducing linear valve so as to have the same pilot pressure, the supply pressure does not become the same pressure. In the case of a movement corresponding to this amount, it is expected that the change in the supply pressure is delayed with respect to the change in the pilot pressure (response delay). The same phenomenon occurs when the pressure is once again maintained from the reduced pressure state and then returned to the reduced pressure state, and when the pressure is maintained from the reduced pressure state through the pressure maintaining state.

  This aspect is an aspect in view of the above, and according to this aspect, in the pressure increase process or the pressure reduction process (hereinafter, referred to as “start process”) to be performed, The supply current to the pressure-increasing linear valve or the pressure-reducing linear valve at the start of the starting process varies depending on whether the preceding process that has been performed is a pressure-increasing process or a pressure-decreasing process. Specifically, when the starting process is a pressure increasing process and the pressure increasing start current to the pressure increasing linear valve is changed, when the preceding process is a pressure reducing process, the preceding process is a pressure increasing process. It is desirable to set the starting current so that the pressure-increasing linear valve can be more easily opened (the opening degree becomes higher) compared to the time when the pressure-increasing linear valve is started. If the preceding process is a pressure-increasing process, the pressure-reducing linear valve is more easily opened (the opening degree is smaller) than when the preceding process is a depressurizing process. It is desirable to set the supply current to be higher.

  According to this aspect, since at least one of the pressure increase start current and the pressure decrease start current is changed, it is possible to appropriately control the supply pressure at the start of at least one of the pressure increase process and the pressure decrease process. It is.

(2) The pressure regulating system according to (1), wherein the control device is configured to execute the supply current change control with respect to both the pressure increase start current and the pressure decrease start current.

  According to this aspect, it is possible to appropriately control the supply pressure at the start of both the pressure increasing process and the pressure reducing process.

(3) The controller is
The supply current to the pressure-increasing linear valve in the pressure-increasing process and the supply current to the pressure-decreasing linear valve in the pressure-decreasing process are configured to control a supply current including a feedforward component based on the supply pressure,
When configured to execute the supply current change control on the pressure increase start current, the control device uses the feedforward component of the pressure increase start current, and the preceding process is a pressure increase process. Is configured to change depending on whether it is a decompression process,
When configured to execute the supply current change control on the pressure reduction start current, the control device uses the feedforward component of the pressure reduction start current, and the preceding process is a pressure increase process. The pressure regulating system according to (1) or (2), wherein the pressure regulating system is configured to be changed depending on whether the pressure reducing process is in progress.

  In this aspect, there is a limitation relating to the control of the electromagnetic linear valve. For example, when the supply pressure to be realized is set as the target supply pressure, the feedforward component based on the supply pressure may be determined as, for example, a current component set in advance according to the target supply pressure. More specifically, for example, when the pilot pressure corresponding to the target supply pressure is reached, the state of the boundary between the valve open state and the valve closed state of the electromagnetic linear valve (hereinafter referred to as “valve open / closed equilibrium state” may be referred to. It is sufficient to determine a supply current such that there is a feedforward component.

  The supply current usually includes a feed forward component based on the supply pressure. In that case, when the pressure increase process and the pressure decrease process start, that is, when the transition from the pressure maintenance process to these processes is performed, The feed forward component greatly affects the accuracy of the supply pressure. In other words, as will be described in detail later, for example, even if the supply current includes a feedback component, the deviation of the actual supply pressure from the target supply pressure is small at the start of the pressure increasing process and the pressure reducing process. This is because the feedback component itself is small and the feedforward component is the main component that determines the supply pressure. In this embodiment, the feedforward component is changed by a preceding process from such a viewpoint. According to this embodiment, the pressure increasing process and the pressure reducing process are performed under a normal electromagnetic linear valve control method. The supply pressure can be appropriately controlled at the start of at least one of the steps.

(4) The relationship between the pressure increase start current and the supply pressure is defined as the pressure increase start characteristic, and the relationship between the pressure decrease start current and the supply pressure is defined as the pressure decrease start characteristic, respectively. The pressure increase start characteristic in the case of a pressure process, the forward pressure increase characteristic, the pressure increase start characteristic in the case where the preceding process is a pressure reduction process, the reverse pressure increase characteristic, and the case where the preceding process is a pressure reduction process In the case where the decompression start characteristic is defined as the forward decompression characteristic and the decompression start characteristic when the preceding process is the pressure increasing process, the reverse decompression characteristic, respectively,
When the control device is configured to execute the supply current change control with respect to the pressure increase start current, the control device acquires the forward pressure increase characteristic and the reverse rotation that are acquired in advance. Determining the feedforward component according to an alternative to the pressure boosting characteristic;
When the control device is configured to execute the supply current change control with respect to the pressure reduction start current, the control device acquires the forward pressure reduction characteristics and the reverse pressure reduction characteristics acquired in advance. The pressure regulation system according to item (3) configured to determine the feedforward component according to the alternative.

  In short, this mode is a mode in which the feedforward component is determined according to the pressure regulation start characteristics (a general term for the pressure increase start characteristics and the pressure decrease start characteristics) respectively acquired by the difference in the preceding process. According to this aspect, since the supply current is determined based on the actually acquired pressure regulation start characteristic, there is a variation in the start characteristic for each pressure regulation system due to a difference in the characteristics of the pressure regulator. Even in such a case, by obtaining a pressure regulation start characteristic peculiar to each pressure regulation system, in any pressure regulation system, at the start of at least one of the pressure increasing process and the pressure reducing process, the supply pressure Can be controlled appropriately.

(5) The relationship between the pressure increase start current and the supply pressure is defined as the pressure increase start characteristic, and the relationship between the pressure decrease start current and the supply pressure is defined as the pressure decrease start characteristic, respectively. The pressure increase start characteristic in the case of a pressure process, the forward pressure increase characteristic, the pressure increase start characteristic in the case where the preceding process is a pressure reduction process, the reverse pressure increase characteristic, and the case where the preceding process is a pressure reduction process In the case where the decompression start characteristic is defined as the forward decompression characteristic and the decompression start characteristic when the preceding process is the pressure increasing process, the reverse decompression characteristic, respectively,
The control device is configured to control a supply current including a feedback component based on the supply pressure as a supply current to the pressure-increasing linear valve in the pressure-increasing process and a supply current to the pressure-decreasing linear valve in the pressure-decreasing process. ,
A pressure-increasing feedback gain that is a feedback gain for determining a feedback component of a supply current to the pressure-increasing linear valve, and a pressure-reduction feedback gain that is a feedback gain for determining a feedback component of a current that is supplied to the pressure-reducing linear valve Are set according to specific rules,
When the pressure increase feedback gain is set according to the specific rule, the specific rule indicates that the pressure increase feedback gain has a magnitude corresponding to the difference between the forward pressure increase characteristic and the reverse pressure increase characteristic. It is a rule that becomes
When the decompression feedback gain is set according to the specific rule, the specific rule is such that the decompression feedback gain has a magnitude corresponding to a difference between the forward decompression characteristic and the reverse decompression characteristic. The pressure regulating system according to any one of (0) to (4), which is a rule.

  In the control of the supply current of the electromagnetic linear valve, feedback control based on the supply pressure is often performed. This feedback control is performed in consideration of control responsiveness. On the other hand, the responsiveness of control depends on the movement of the spool of the pressure regulator, and the responsiveness deteriorates when the movement of the spool is not smooth. The above-described friction, the biasing force of the return spring, and the like affect the movement of the spool. As can be seen from the above description, the reverse rotation characteristic (generic name for the reverse pressure increase characteristic and reverse pressure reduction characteristic) is affected by friction and the like, so the reverse rotation characteristic and the forward characteristic (forward pressure increase characteristic, forward pressure reduction) A large difference from the general name of the characteristic indicates that the spool movement is poor. In this aspect, this is taken into consideration, and the feedback gain of the supply current of at least one of the pressure-increasing linear valve and the pressure-reducing linear valve (which is a general term for the pressure-increasing feedback gain and the pressure-reducing feedback gain) is determined according to the difference. By adjusting the size, good responsiveness is secured in controlling the supply pressure. In other words, even if there are variations in the characteristics of the pressure regulator for each pressure regulation system, a good response can be achieved in any pressure regulation system by setting a feedback gain according to each pressure regulation system. Sex is guaranteed. In the case where the feedback component is determined by multiplying the deviation of the actual supply pressure with respect to the target supply pressure by the feedback gain, specifically, the “specific rule” is, for example, the reverse rotation characteristic. The rule may be to increase the feedback gain as the difference between the antegrade characteristic and the forward characteristic increases.

(6) The pressure regulating system according to (5), wherein both the pressure increase feedback gain and the pressure reduction feedback gain are set according to the specific rule.

  According to this aspect, since the feedback gains of both the pressure-increasing linear valve and the pressure-reducing linear valve are set to a magnitude corresponding to the difference, a suitable response is obtained in both the pressure-increasing process and the pressure-decreasing process. Secured.

(11) a brake operation member operated by the driver;
A brake device provided on the wheel for generating a braking force;
(1) The pressure adjusting system according to any one of items (6) to (6) and the hydraulic fluid adjusted in pressure by the pressure regulator are introduced, and the hydraulic fluid is adjusted to a pressure corresponding to the pressure of the introduced hydraulic fluid. And a master cylinder device that supplies the pressurized hydraulic fluid to the brake device,
With
The control device controls the supply current to the pressure-increasing linear valve in the pressure-increasing process and the current to the pressure-decreasing linear valve in the pressure-decreasing process in accordance with the operation of the brake operation member. A vehicle hydraulic brake system configured to control a braking force to be generated.

  This aspect is an aspect different from the above-described aspects in a category, and is an aspect relating to a vehicle hydraulic brake system configured to include the above-described pressure regulating system. According to this aspect, the merit by the pressure regulation system of each said aspect is utilized, and control of favorable brake force is attained.

(21) In the pressure regulating system according to item (0), a pressure increase start which is a relationship between a pressure increase start current which is a supply current to the pressure increase linear valve at the start of a pressure increase process and the supply pressure. A pressure regulation characteristic acquisition method for acquiring at least one of a characteristic and a pressure reduction start characteristic that is a relationship between a supply pressure and a pressure reduction start current that is a supply current to the pressure reduction linear valve at the start of a pressure reduction process, ,
The pressure increase start pressure is sequentially changed between the pressure increase start pressure that is the supply pressure at the time when the pressure increase process is started and the supply current to the pressure increase linear valve at that time as the pressure increase start current. However, a pressure increase characteristic acquisition step for acquiring a case where the preceding process, which is one of the pressure increasing process and the pressure reducing process performed before the pressure increasing process, is a pressure reducing process,
The pressure reduction start pressure, which is the supply pressure at the time when the pressure reduction process is started, and the supply current to the pressure reduction linear valve at that time as the pressure reduction start current, while sequentially changing the pressure reduction start pressure, the preceding pressure A pressure regulation characteristic acquisition method comprising: at least one of a pressure reduction characteristic acquisition step acquired when the process is a pressure increase process.

  This aspect relates to a method for obtaining a pressure regulation characteristic, and in short, is characterized by obtaining the above-described reverse characteristic in at least one of a pressure increasing process and a pressure reducing process. By utilizing at least one of the acquired reverse pressure-increasing characteristics and reverse pressure-reducing characteristics, at the start of at least one of the pressure-increasing process and the pressure-reducing process, even if those processes are different from the preceding processes, The supply pressure can be appropriately controlled.

(22) The pressure regulation characteristic acquisition method according to item (21), which includes both the pressure increase characteristic acquisition step and the pressure reduction characteristic acquisition step, and acquires both the pressure increase start characteristic and the pressure reduction start characteristic.

  According to this aspect, both the reverse pressure-increasing characteristic and the reverse pressure-decreasing characteristic can be acquired, and by using both of these characteristics, both the pressure-increasing process and the pressure-decreasing process can be performed when the starting process is different from the preceding process. Even when these processes are different from the preceding processes at the start of the operation, the supply pressure can be appropriately controlled.

(23) When the pressure regulation characteristic acquisition method includes the pressure increase characteristic acquisition step,
The step of acquiring pressure increase characteristics
After the pressure increasing linear valve is closed, the pressure reducing linear valve is opened to realize a pressure reducing process, and then the pressure reducing linear valve is closed, and after the valve closing, the pressure increasing linear valve is opened. In order to make the valve, the supply current to the pressure-increasing linear valve is gradually changed, and when the pressure-increasing process starts in the middle of the change, the supply pressure is used as the pressure-increasing start pressure to the pressure-increasing linear valve. The pressure regulation characteristic acquisition method according to item (21) or (22), including a plurality of reverse pressure increase acquisition steps for acquiring each supply current as the pressure increase start current.

(24) When the pressure regulation characteristic acquisition method includes the pressure reduction characteristic acquisition step,
The decompression characteristic acquisition step is
After the pressure-reducing linear valve is closed, the pressure-increasing linear valve is opened to realize the pressure-increasing process, and then the pressure-increasing linear valve is closed. In order to open the valve, the supply current to the pressure-reducing linear valve is gradually changed, and when the pressure-reduction process starts in the middle of the change, the supply pressure is set as the pressure-reduction starting pressure. The pressure regulation characteristic acquisition method according to any one of items (21) to (23), which includes a plurality of reverse pressure reduction acquisition steps that are respectively acquired as the pressure reduction start current.

  To put it simply, the above-described two modes are modes in which limitations on how to acquire the reverse pressure increase characteristic and the reverse pressure decrease characteristic are added. According to those aspects, it is possible to easily acquire the reverse pressure increase characteristic and the reverse pressure decrease characteristic.

(25) The pressure regulation characteristic acquisition method includes both the pressure increase characteristic acquisition step and the pressure reduction characteristic acquisition step,
The pressure increase characteristic acquisition step includes:
After the pressure increasing linear valve is closed, the pressure reducing linear valve is opened to realize a pressure reducing process, and then the pressure reducing linear valve is closed, and after the valve closing, the pressure increasing linear valve is opened. In order to make the valve, the supply current to the pressure-increasing linear valve is gradually changed, and when the pressure-increasing process starts in the middle of the change, the supply pressure is used as the pressure-increasing start pressure to the pressure-increasing linear valve. Including a plurality of reverse pressure increase acquisition steps to acquire each of the supply current as the pressure increase start current,
The decompression characteristic acquisition step comprises:
After the pressure-reducing linear valve is closed, the pressure-increasing linear valve is opened to realize the pressure-increasing process, and then the pressure-increasing linear valve is closed. In order to open the valve, the supply current to the pressure-reducing linear valve is gradually changed, and when the pressure-reduction process starts in the middle of the change, the supply pressure is set as the pressure-reduction starting pressure. Including a plurality of reverse decompression acquisition steps to obtain each as a decompression start current,
The pressure regulation characteristic acquisition method according to any one of (21) to (24), wherein the reverse pressure increase acquisition step and the reverse pressure decrease acquisition step are alternately and continuously performed.

  This aspect limits the order of performing a plurality of reverse pressure-increasing acquisition steps and a plurality of reverse pressure-increasing acquisition steps in order to acquire both the reverse pressure-increasing characteristics and the reverse pressure-increasing characteristics. This is an added embodiment. According to this aspect, it is possible to acquire both the reverse pressure increase characteristic and the reverse pressure increase characteristic relatively quickly.

(26) When the pressure regulation characteristic acquisition method includes the pressure increase characteristic acquisition step,
In the pressure increase characteristic acquisition step,
The pressure increase start pressure is sequentially changed between the pressure increase start pressure that is the supply pressure at the time when the pressure increase process is started and the supply current to the pressure increase linear valve at that time as the pressure increase start current. However, the pressure regulation characteristic acquisition method according to any one of items (21) to (25), which is acquired even when the preceding process is a pressure increase process.

(27) The step of acquiring pressure increase characteristics includes:
After the pressure-reducing linear valve is closed, the pressure-increasing linear valve is opened to realize the pressure-increasing process, and then the pressure-increasing linear valve is closed.
A plurality of steps continuously performed after the step of maintaining the booster closed valve, and in order to open the booster linear valve, the supply current to the booster linear valve is gradually changed. When the pressure increasing process starts in the middle of the change, the supply pressure is used as the pressure increase start pressure, and the supply current to the pressure increase linear valve is used as the pressure increase start current. The pressure regulation characteristic acquisition method according to item (26), including a pressure acquisition step.

  In short, the above-described two modes are modes in which the above-described forward pressure increase characteristic is also acquired as the pressure increase characteristic. By acquiring the antegrade pressure increase characteristic, the supply current change control described above is executed at the start of the pressure increase process using the acquired reverse pressure increase characteristic and antegrade pressure increase characteristic. can do.

(28) When the pressure regulation characteristic acquisition method includes the pressure reduction characteristic acquisition step,
In the decompression characteristic acquisition step,
The pressure reduction start pressure, which is the supply pressure at the time when the pressure reduction process is started, and the supply current to the pressure reduction linear valve at that time as the pressure reduction start current, while sequentially changing the pressure reduction start pressure, the preceding pressure The pressure regulation characteristic acquisition method according to any one of items (21) to (27), which is acquired even when the process is a pressure reduction process.

(29) The decompression characteristic acquisition step includes:
A decompression closed maintaining step of closing the decompression linear valve after opening the decompression linear valve and realizing a decompression process in a state in which the pressure increasing linear valve is closed; and
A plurality of steps continuously performed after the pressure reducing and closing valve maintaining step, wherein the supply current to the pressure reducing linear valve is gradually changed in order to open the pressure reducing linear valve, and in the middle of the gradually changing A plurality of antegrade decompression acquisition steps, each of which is acquired at the time when the decompression process is started as the decompression start pressure and the supply current to the decompression linear valve as the decompression start current. The method for obtaining pressure regulation characteristics according to item 28).

  To put it simply, the above-described two modes are modes in which the above-described forward pressure reduction characteristic is also acquired as the pressure reduction characteristic. By acquiring the antegrade pressure reduction characteristic, the supply current change control described above can be executed at the start of the pressure reduction process using the acquired reverse pressure reduction characteristic and antegrade pressure reduction characteristic. .

It is a figure which shows the whole structure of the hydraulic brake system for vehicles of the Example comprised including the regulator which is a pressure regulator of an Example. It is sectional drawing which expands and shows a regulator. It is a principal part expanded sectional view for demonstrating the action | operation of a regulator. It is sectional drawing which shows the structure of a pressure increase linear valve and a pressure reduction linear valve. It is a graph for demonstrating the pressure regulation characteristic of the pressure regulation system of the Example comprised including a regulator, a pressure increase linear valve, and a pressure reduction linear valve. It is a flowchart which shows the brake control program performed in the hydraulic brake system for vehicles of an Example. It is a graph for demonstrating the antegrade pressure increase characteristic acquisition step and antegrade pressure reduction characteristic acquisition step in the pressure regulation characteristic acquisition method of an Example. 5 is a graph for explaining a reverse rotation characteristic acquisition step, specifically, a reverse pressure increase characteristic acquisition step and a reverse pressure reduction characteristic acquisition step in the pressure regulation characteristic acquisition method of the embodiment.

  DESCRIPTION OF EMBODIMENTS Hereinafter, embodiments of the claimable invention will be described in detail with reference to the drawings as modes for carrying out the claimable invention. In addition to the following examples, the claimable invention is implemented in various forms including various modifications and improvements based on the knowledge of those skilled in the art, including the form described in the above [Aspect of the Invention] section. can do.

[A] Configuration of hydraulic brake system for vehicle
i) Overall Configuration As shown in FIG. 1, the vehicle hydraulic brake system including the pressure regulating system according to the embodiment includes a brake device 12 provided on each wheel 10, an ABS unit 14, and the like. A master cylinder device 16 that pressurizes the hydraulic fluid and supplies the pressurized hydraulic fluid to the brake device 12 via the ABS unit 14; a brake pedal 18 that is a brake operation member connected to the master cylinder device 16; , A high-pressure source device 20 that is a high-pressure source, a regulator 22 that regulates high-pressure hydraulic fluid from the high-pressure source device 20 and supplies it to the master cylinder device 16, and a regulator 22 that is supplied from the high-pressure source device 20. A pressure-increasing linear valve 24 and a pressure-reducing linear valve 26, which are electromagnetic linear valves for adjusting the pressure of the hydraulic fluid as a pilot pressure, A reservoir 28 as a source, the electronic control unit as a control device for controlling of the hydraulic brake system is configured to include a (hereinafter sometimes referred to as "ECU") 30. Since all the constituent elements listed are publicly known, the following description will be briefly described except those highly relevant to the claimable invention. Incidentally, the pressure regulating system of the embodiment includes a regulator 22, a pressure-increasing linear valve 24, a pressure-decreasing linear valve 26, and an ECU 30.

ii) Brake device and ABS unit The brake device 12 is a general caliper type disc brake device including a brake cylinder, and the ABS unit 14 is also a general function that functions when the wheel 10 slips. Is. Therefore, the description here is omitted in view of the fact that the technical relationship with the claimable invention is thin.

iii) Master Cylinder Device The master cylinder device 16 has a housing 44 in which the interior is partitioned into a front chamber and a rear chamber by an annular partition wall 40, and a stroke simulator 42 is integrally provided. A first pressurizing piston 46 and a second pressurizing piston 48 are disposed in the front chamber, and an input piston 50 having a brake pedal 18 connected to the rear end portion is disposed in the rear chamber. . The first pressurizing piston 46 and the second pressurizing piston 48 pressurize the hydraulic fluid by moving forward, respectively, and apply the pressurized hydraulic fluid to the brake device 12 on the front wheel side and the brake device 12 on the rear wheel side. Supply. The input piston 50 moves forward by the brake operation force δ _PDL applied to the brake pedal 18. Incidentally, the brake operation force δ _PDL is detected by the operation force sensor 52.

  The second pressurizing piston 48 extends through the partition wall 40 and extends into the rear chamber, and an inter-piston chamber R <b> 1 is formed between the second pressurizing piston 48 and the input piston 50. The second pressurizing piston 48 has a flange 54, and an annular input chamber R <b> 2 is formed between the flange 54 and the partition wall 40. As will be described later, the hydraulic fluid regulated by the regulator 22 is introduced into the input chamber R2. On the other hand, on the front side of the flange 54, an annular facing chamber R3 that faces the input chamber R2 across the flange 54 is formed. The working fluid in the facing chamber R3 is introduced into the stroke simulator 42.

When the vehicle is operating in a normal state (when the ignition switch is turned on), the on-off valve 60 causes the inter-piston chamber R1 and the counter chamber R3 to communicate with each other to form one liquid chamber. The chamber is disconnected from the reservoir 28 by an on-off valve 62. In order to generate a force for moving the second pressure piston 48 forward, the pressure receiving area of the second pressure piston 48 that receives the pressure of the hydraulic fluid in the inter-piston chamber R1, and the second pressure piston 48 rearward. The pressure receiving area of the second pressurizing piston 48 that receives the pressure of the hydraulic fluid in the facing chamber R3 in order to generate the force in the direction of movement is made equal, so that the brake operating force δ _PDL applied to the brake pedal 18 is The second pressure piston 48 is not transmitted via the input piston 50. In this state, the second pressurizing piston 48 moves forward due to the pressure of the hydraulic fluid in the input chamber R2, and the brake device 12 generates a braking force having a magnitude corresponding to the pressure of the hydraulic fluid in the input chamber R2.

Although detailed description is omitted, when an electrical failure or the like occurs (an example of an abnormal state), the on / off valve 60 is closed and the on / off valve 62 is opened, so that the input piston 50 is opened. Comes into contact with the second pressurizing piston 48, and the brake operating force δ _PDL is transmitted to the second pressurizing piston 48 via the input piston 50. In this state, the brake device 12 A braking force depending on the operating force δ _PDL can be generated.

iv) High-pressure source device The high-pressure source device 20 includes a pump device 64 that pumps the hydraulic fluid from the reservoir 28 and pressurizes it, and an accumulator 66 that stores the pressurized hydraulic fluid. The pressure of the hydraulic fluid supplied from the high pressure source device 20 as an accumulator pressure P _ACC, which is monitored by the accumulator pressure sensor 68, during operation of the vehicle, as the accumulator pressure P _ACC falls within a set range, the pump Device 64 is controlled.

v) Regulator The regulator 22 is a spool valve type pressure regulator mainly composed of a spool valve mechanism 80, and will be described with reference to FIG. A piston 86 and a movable sleeve 88 are provided. More specifically, the spool 84 is held by the spool holding cylinder 90 so as to be movable in the axial direction. The piston 86 includes a bottomed cylindrical case 92 and a movable rod 94 having a base end held by the case 92. The distal end portion of the movable rod 94 is held by a movable sleeve 88.

If the left side of the regulator 22 is called one end side and the right side is called the other end side, the first pilot pressure chamber is located between one end side of the spool 84 and the other end side of the piston 86, that is, between them. R4 is formed, the second pilot pressure chamber R5 is introduced into one end side of the piston 86, and the pressure of the hydraulic fluid supplied from the regulator 22 is introduced into the other end side of the spool 84. The pressure regulating chambers R6 are respectively formed.

  The housing 82 is supplied with a high pressure port P 1 communicating with the high pressure source device 20, a low pressure port P 2 communicating with the reservoir 28 via the master cylinder device 16, and hydraulic fluid regulated by the regulator 22 to the master cylinder device 16. Pressure adjusting port P3, first pilot introduction port P4 for introducing hydraulic fluid into first pilot pressure chamber R4, first pilot discharge port P5 for discharging hydraulic fluid from first pilot pressure chamber R4, Second pilot ports P6 and P7 are provided for making the two pilot pressure chambers R5 a fluid passage between the master cylinder device 16 and the brake device 12, respectively.

  The spool valve mechanism 80 having the spool 84 as a main component will be described in detail. The spool holding cylinder 90 has a high-pressure port P1, a low-pressure port P2, and a pressure-regulating port through internal liquid passages formed in the housing 82, respectively. A high-pressure liquid passage 96, a low-pressure liquid passage 98, and a pressure-regulating liquid passage 100 connected to P3 are formed, and each of the liquid passages 96, 98, 100 is opened to the inner periphery of the spool holding cylinder 90. These openings function as an internal high pressure port P8, an internal low pressure port P9, and an internal pressure regulation port P10, respectively. An annular groove 102 is formed on the inner peripheral surface of the spool holding cylinder 90. On the other hand, two annular grooves 104 and 106 are formed side by side in the axial direction on the outer peripheral surface of the spool 84.

  The spool 84 is urged toward one end by a return spring 108 that is a compression coil spring. Further, in the state shown in the figure, the end surface on one end side of the spool 84 is locked to the locking piece portion 110 formed on the movable sleeve 88, and the spool 84 is a specific position on one end side in the movable range. Located in the locking position.

In a normal state (a state in which no electrical failure or the like has occurred), the spool 84 adjusts the pressure of the hydraulic fluid in the first pilot pressure chamber R4 (hereinafter sometimes referred to as “pilot pressure P _PLT ”) and the pressure regulation. It moves to one end side or the other end side due to a deviation in balance with the pressure of the hydraulic fluid in the chamber R6. Specifically, the pilot pressure P _PLT urges the spool 84 to the other end side, and the pressure of the hydraulic fluid in the pressure regulating chamber R6 urges the spool 84 to the one end side. When the balance of the urging forces is lost, the spool 84 moves. The pressure regulating chamber R6 communicates with the pressure regulating port P3, and the pressure of the hydraulic fluid in the pressure regulating chamber R6 is a supply pressure (controlled pressure) that is the pressure of the hydraulic fluid supplied from the regulator 22. Hereinafter, it may be referred to as “servo pressure P _SRV ”). Therefore, the spool 84 moves depending on the relationship between the pilot pressure P _PLT and the servo pressure P _SRV . Strictly speaking, the urging force of the return spring 108 also urges the spool 84 to one end side, but this urging force is relatively small, and in the following description, it is easy to understand except in special cases. In consideration, the force will be ignored.

3A, when the spool 84 is in the locking position, the internal high pressure port P8 is blocked by the spool 84, and the internal low pressure port P9 is the other end side of the spool 84. Is connected to the pressure regulating chamber R6 at the end. That is, the communication between the low pressure port P2 and the pressure regulating port P3 is allowed and the communication between the high pressure port P1 and the pressure regulating port P3 is blocked. This state is a state in which the servo pressure P _SRV is allowed to drop when the servo pressure P _SRV is higher than the pressure corresponding to the pilot pressure P _PLT (hereinafter sometimes referred to as “reduced pressure state”).

On the other hand, when the _urging force by the pilot pressure P _PLT becomes larger than the _urging force by the servo pressure P _SRV , the spool 84 moves to the other end side. When moved to the position shown in FIG. 3B, more specifically, when the movable range moves from the locking position by a predetermined distance L, the internal low pressure port P9 is blocked by the spool 84, and the internal high pressure port P8 and the internal pressure regulating port P10 are connected via the annular grooves 102, 104, and 106. That is, the communication between the high pressure port P1 and the pressure regulating port P3 is allowed and the communication between the low pressure port P2 and the pressure regulating port P3 is blocked. This state is a state in which the increase of the servo pressure _PSRV is allowed (hereinafter sometimes referred to as an “increasing pressure state”).

In an intermediate state between the reduced pressure state and the increased pressure state, that is, in a state where the spool 84 has moved from the locking position to the other end side but has not moved to the predetermined distance L, the internal high pressure port P8 and the internal low pressure Both the port P9 and the port P9 are closed by the spool 84. That is, both the high pressure port P1 and the low pressure port P2 are in a state where communication with the pressure regulating port P3 is blocked. In this state, the servo pressure _PSRV is maintained at that pressure without increasing or decreasing. Therefore, this state is hereinafter sometimes referred to as a “pressure maintaining state”.

By the action of the spool valve mechanism 80 as described above, in the present regulator 22, the hydraulic fluid supplied from the regulator 22 so that the servo pressure _PSRV becomes a pressure corresponding to the pilot pressure _PPLT , that is, the master cylinder. Specifically, the hydraulic fluid supplied to the input chamber R2 of the device 16 is regulated. The servo pressure P _SRV is monitored by the servo pressure sensor 112. Incidentally, if the movement of the spool 84, which will be described in detail later, is not considered, the ratio between the pilot pressure P _PLT and the servo pressure P _SRV , that is, the pressure regulation ratio R _P (= P _SRV / P _PLT ) is the theoretical pressure regulation ratio. R _P0 .

Incidentally, an effective pilot pressure P _PLT is not generated in a state of electrical failure or the like, but instead of the pilot pressure P _PLT , the pressure of the hydraulic fluid introduced into the second pilot pressure chamber R5 is adjusted. The pressure of the hydraulic fluid supplied from the regulator 22 can be regulated by the balance with the pressure of the hydraulic fluid in the pressure chamber R6. The description of the function is omitted.

vi) Pressure-increasing linear valve and pressure-reducing linear valve The pressure-increasing linear valve 24 has the structure shown in FIG. 4A, and includes a housing 160, a coil 162, and a plunger 164 disposed in the housing 160. It is configured to include. The lower end of the housing 160 functions as the input port P11 and communicates with the high pressure source device 20. On the other hand, an output port P12 is provided in the side peripheral portion of the housing 160, and the output port P12 communicates with the first pilot introduction port P4 of the regulator 22, that is, the first pilot pressure chamber R4. The housing 160 is provided with a valve seat 166, and the plunger 164 is configured such that a lower end portion that functions as a valve element can be seated and separated from the valve seat 166. A spring 168 that is a compression coil spring urges the plunger 164 in a direction in which the tip of the plunger 164 is seated on the valve seat 166 (hereinafter sometimes referred to as “seat direction”) (hereinafter referred to as the urging force). May be referred to as “elastic urging force F _K ”). The upper end portion of the housing 160 functions as a core, and by supplying current to the coil 162, the direction in which the tip of the plunger 164 separates from the valve seat 166 with respect to the plunger 164 (hereinafter referred to as “seating direction”). generating an electromagnetic force acting F _E acting on there). The electromagnetic acting force F _E increases as the supplied current increases. On the other hand, the difference between the pressure of the working fluid at the output port P12 and pressure of the working fluid at the input port P11, i.e., the accumulator pressure P _ACC and the pilot pressure P pressure differential force F _P based on the pressure difference between _{the PLT,} the plunger Acts in the direction away from 164.

From the above-described structure, the pressure-increasing linear valve 24 is an electromagnetic linear valves normally closed, by considering elastic biasing force F _K, the electromagnetic force acting F _E, the balance for force F _P differential pressure acting the By controlling the current supplied to the pressure-increasing linear valve 24 (hereinafter sometimes referred to as “supply current I _A ”), hydraulic fluid having a pressure corresponding to the supply current I _A is supplied to the first pilot of the regulator 22. Supply to pressure chamber R4. Incidentally, as the supply current I _A is increased, the opening degree (ease of valve opening) is increased, and a high-pressure hydraulic fluid can be supplied to the first pilot pressure chamber R4.

On the other hand, the pressure-reducing linear valve 26 has the structure shown in FIG. 4B, and includes the housing 170, the coil 172, and the plunger 174, similarly to the pressure-increasing linear valve 24. . The lower end of the housing 170 functions as the input port P13 and communicates with the first pilot discharge port P5 of the regulator 22, that is, the first pilot pressure chamber R4. On the other hand, an output port P <b> 14 is provided on the side periphery of the housing 170, and the output port P <b> 14 communicates with the reservoir 28 via the master cylinder device 16. Similar to the pressure-increasing linear valve 24, the housing 170 is provided with a valve seat 176, and the plunger 174 has a lower end functioning as a valve element that can be seated and separated from the valve seat 176. In the pressure-reducing linear valve 26, the spring 178 is a compression coil spring urges the plunger 174 in the separating direction by the elastic biasing force F _K. The upper end portion of the plunger 174 functions as a core, and by supplying a current to the coil 172, an electromagnetic acting force F _E acting on the plunger 174 in the seating direction is generated. The electromagnetic acting force F _E increases as the supplied current increases. On the other hand, the differential pressure based on the difference between the pressure of the hydraulic fluid at the input port P13 and the pressure of the hydraulic fluid at the output port P14, that is, the pressure difference between the pilot pressure P _PLT and the reservoir pressure P _ATM (generally atmospheric pressure). acting force F _P is, relative to the plunger 174, acting in separating direction.

From the above-described structure, the pressure-reducing linear valve 26 is a normally open type electromagnetic linear valves, the reduced pressure in consideration of elastic biasing force F _K, the electromagnetic force acting F _E, the balance of the differential pressure acting force F _P By controlling the current supplied to the linear valve 26 (hereinafter sometimes referred to as “supply current I _R ”), the pressure of the first pilot pressure chamber R 4 of the regulator 22 is adjusted to the pressure corresponding to the supply current I _R. Maintain hydraulic fluid pressure. Incidentally, the larger the supply current I _R, the opening degree is low, and is it possible to maintain a high pressure of the working fluid in the first pilot chamber R4.

[B] Pressure regulation characteristic of spool valve type pressure regulator As described above, the regulator 22 is a spool valve type pressure regulator, and the servo pressure P _{SRV is changed} to a pressure corresponding to the pilot pressure P _PLT as the spool 84 moves. Adjust. When switching from the process of increasing the servo pressure P _SRV (hereinafter sometimes referred to as “pressure increasing process”) to the process of maintaining the servo pressure P _SRV (hereinafter also referred to as “pressure maintaining process”), The spool 84 moves from the position shown in FIG. 3B to a position slightly shifted to one end side. Next, when switching to the pressure increasing process again, the position slightly moves from the shifted position and returns to the position shown in FIG. On the other hand, when the process proceeds from the pressure increasing process to the process in which the servo pressure _PSRV decreases (hereinafter sometimes referred to as “the pressure reducing process”) through the pressure maintaining process, the spool 84 is configured as shown in FIG. ), I.e., the above-mentioned locking position, and the movement distance corresponds to the predetermined distance L in general.

  Similarly, when the pressure reducing process is switched to the pressure maintaining process, the spool 84 moves from the position shown in FIG. 3A to a position slightly shifted to the other end side. Next, when switching to the decompression process again, the position slightly moves from the shifted position and returns to the position shown in FIG. On the other hand, when shifting from the pressure reducing process to the pressure increasing process through the pressure maintaining process, the spool 84 must move to the position shown in FIG. This corresponds to the predetermined distance L.

Relationship between the servo pressure P _SRV and the pilot pressure P _PLT at the start in the process of starting (hereinafter sometimes referred to as “start process”) due to the presence or absence of movement of the spool 84 of the predetermined distance L Is different depending on the process performed before the start process (which is either a pressure increasing process or a pressure reducing process, and may be referred to as a “preceding process” hereinafter). Specifically, when starting the pressure increasing process from a certain servo pressure _PSRV, when the preceding process is a pressure reducing process, the pilot pressure P _PLT is compared with the case where the preceding process is a pressure increasing process. should be higher, conversely, when starting the depressurization process from one servo pressure P _SRV, if the preceding process is more increased-pressure, as compared with the case prior process is depressurizing process, the pilot pressure P _PLT needs to be lowered. In these cases, when the spool 84 is moved by a predetermined distance L, it is necessary to supply and discharge the hydraulic fluid corresponding to the movement to the pilot pressure chamber. This is because it is necessary to overcome the frictional force that is received. In other words, the urging force of the return spring 108 is different by a predetermined distance L.

As will be described in detail later, the adjustment of the pilot pressure P _PLT is performed by changing the supply current I _A to the pressure-increasing linear valve 24 in the pressure increasing process, and the pressure to the pressure reducing linear valve 26 in the pressure decreasing process. This is done by changing the supply current I _R. Therefore, as can be seen from the structure of the pressure increasing linear valve 24 and the pressure reducing linear valve 26, when the pressure increasing process is started, the preceding process is a pressure reducing process, compared with the case where the preceding process is a pressure increasing process. Thus, in order to increase the opening degree of the pressure increasing linear valve 24, it is necessary to increase the supply current I _A. When the preceding process is a pressure increasing process at the start of the pressure reducing process, the preceding process is reduced. Compared to the process, the supply current I _R needs to be reduced in order to increase the opening of the pressure reducing linear valve 26. Otherwise, when the start process is different from the preceding process, the start of the increase / decrease of the servo pressure _PSRV is delayed, that is, a response delay occurs.

From the foregoing, the servo pressure P _SRV and the supply current I _A at the start of the starting process, the relationship between I _R, In detail, the supply and the servo pressure P _SRV when servo pressure P _SRV starts changing current I _A , I _R is a pressure regulation start characteristic (a kind of pressure regulation characteristic) as shown in the graph of FIG. FIG. 5A shows the relationship between the servo pressure P _SRV and the supply current I _A to the pressure-increasing linear valve 24 at the start of the pressure-increasing process, that is, the pressure-increasing start characteristic, and FIG. The relationship between the servo pressure P _{SRV at} the start of the process and the supply current I _R to the pressure-reducing linear valve 26, that is, the pressure-reducing start characteristic is shown.

One characteristic line in FIG. 5A shows a characteristic when the preceding process is a pressure increasing process, that is, a forward pressure increasing characteristic, and the other characteristic line is a characteristic when the preceding process is a pressure reducing process. That is, the reverse pressure increase characteristic is shown. As can be seen from FIG. 5A, even when the servo pressure _PSRV is to be increased from the same pressure, when the reverse pressure increasing characteristic is followed, the pressure increasing linear valve 24 is more effective than when the forward pressure increasing characteristic is followed. The supply current I _{A to} is increased. Similarly, one characteristic line in FIG. 5B shows a characteristic when the preceding process is a pressure reducing process, that is, a forward pressure reducing characteristic, and the other characteristic line shows a case where the preceding process is a pressure increasing process. This shows the reverse pressure reduction characteristics. As can be seen from FIG. 5B, even when the servo pressure _PSRV is to be lowered from the same pressure, the supply to the pressure-reducing linear valve 26 is greater when the reverse pressure reduction characteristic is followed than when the forward pressure reduction characteristic is followed. The current I _R is small.

As can be seen from the above description, the antegrade pressure increase characteristic, the antegrade pressure reduction characteristic, the antegrade characteristic, the reverse pressure increase characteristic, the reverse pressure reduction characteristic, and the reverse characteristic are collectively referred to as an appropriate servo pressure P. If an attempt is made to control the _SRV , that is, to control an appropriate braking force in the vehicle hydraulic brake system, the current supplied to the pressure increasing linear valve 24 and the pressure reducing linear valve 26 at the start of the pressure increasing process and the pressure reducing process is Whether to depend on the forward characteristic or the reverse characteristic is determined according to the preceding process, and the supply currents I _A and I _R to the pressure increasing linear valve 24 and the pressure reducing linear valve 26 are determined according to the determined characteristics. Should be.

The pressure regulation start characteristics described above vary depending on the pressure regulation system. That is, there is a solid difference. Therefore, the pressure regulation start characteristic is acquired for each pressure regulation system, and the pressure increase linear valve 24 and the pressure reduction linear at the start of the pressure increase process and the pressure reduction process are acquired for each pressure adjustment system based on the acquired pressure adjustment start characteristic. It is desirable to determine the supply currents I _A and I _R to the valve 26. The acquisition of this pressure regulation start characteristic will be described later. In addition, since the pressure regulation start characteristic is influenced not only by the regulator 22, but also by individual differences between the pressure increasing linear valve 24 and the pressure reducing linear valve 26, the pressure regulation starting characteristics acquired for each pressure regulating system are those The characteristic also depends on the individual difference between the pressure-increasing linear valve 24 and the pressure-reducing linear valve 26.

Further, as shown in FIG. 5, the difference between the forward pressure increasing characteristic and the reverse pressure increasing characteristic, for example, the supply current I _A to the pressure increasing linear valve 24 at a specific servo pressure _PSRV is expressed as the pressure increasing characteristic. If the difference ΔC _A is the difference between the forward pressure reducing characteristic and the reverse pressure reducing characteristic, for example, the supply current I _R to the pressure reducing linear valve 26 at a specific servo pressure P _SRV is the pressure reducing characteristic difference ΔC _R , the pressure increases. The characteristic difference ΔC _A and the pressure reduction characteristic difference ΔC _R (hereinafter, collectively referred to simply as “characteristic difference ΔC”) are parameters indicating the ease of movement of the spool 84. In other words, increasing pressure characteristics gender [Delta] C _A, reduced pressure characteristic difference [Delta] C _R is as their values is large, the spool 84 is shown that hardly move.

The movement of the spool 84 affects the responsiveness in controlling the servo pressure _PSRV . More specifically, when the spool 84 is difficult to move, the control response of the servo pressure _PSRV is deteriorated. On the other hand, as will be described in detail later, in order to improve control responsiveness, a feedback component based on the servo pressure P _SRV is _added to the supply currents I _A and I _R to the pressure increasing linear valve 24 and the pressure reducing linear valve 26. Inclusion is generally done. As will be described in detail later, the feedback gain used in determining the feedback component is set according to a specific rule. Specifically, the feedback gain is set according to a rule such that the feedback gain has a magnitude corresponding to the characteristic difference ΔC. Thus, regardless of the individual difference in the characteristics of the regulator 22, the responsiveness in the control of the servo pressure _PSRV can be made appropriate in each pressure regulating system. Specifically, the feedback gain in each pressure regulating system may be set based on a rule that the feedback gain is increased as the characteristic difference ΔC is larger.

Strictly speaking, the supply currents I _A and I _R to the pressure increasing linear valve 24 and the pressure reducing linear valve 26 corresponding to a certain pilot pressure P _PLT differ depending on the accumulator pressure P _ACC and the reservoir pressure P _ATM at that time. This is because pressure differential force F _P described above, becomes a pilot pressure P _PLT, the difference force corresponding to the accumulator pressure P _ACC or reservoir pressure P _ATM. The change in the reservoir pressure P _ATM can be ignored. However, considering that the accumulator pressure P _ACC changes within the above set range, the accumulator pressure P _A is supplied to the supply current I _A to the pressure-increasing linear valve 24. It is desirable to control taking into account changes in _ACC . In this case, as for the pressure increase start characteristic, for example, the difference between the pilot pressure P _PLT estimated based on the theoretical pressure adjustment ratio R _P0 from the servo pressure P _SRV and the accumulator pressure P _ACC , and the pressure increase linear valve 24 It is desirable to have a relationship with the supply current I _A to the. These will be described in detail at the end, and the accumulator pressure P _ACC is treated as being hardly changed in the description so far and the explanation from here on in view of the simplification of the explanation.

[C] Control of hydraulic brake system for vehicle
i) Outline of control The ECU 30 controls the vehicle hydraulic brake system. As described above, the high-pressure source device 20 is controlled by the pump device 64 so that the accumulator pressure P _ACC falls within the set range. In the normal state, the on-off valve 60 and the on-off valve 62 are excited, and as described above, the master cylinder device 16 operates at a pressure corresponding to the pressure of the hydraulic fluid introduced into the input chamber R2, that is, the regulator 22. the hydraulic fluid pressure corresponding to the pressure of the supplied hydraulic fluid (servo pressure P _SRV) is supplied to the brake device 12 from the braking device 12, generates a braking force having a magnitude corresponding to the servo pressure P _SRV Let Therefore, the brake force is controlled by the ECU 30 supplying current to the pressure increasing linear valve 24 and the pressure reducing linear valve 26 so as to adjust the pressure of the hydraulic fluid (pilot pressure P _PLT ) in the first pilot pressure chamber R4 of the regulator 22. This is done by controlling I _A and I _R.

The vehicle on which the hydraulic brake system is mounted is a so-called hybrid vehicle, and a regenerative brake is adopted. Therefore, the brake device 12 has a brake having a magnitude corresponding to the brake operation force applied to the brake pedal 18. It does not need to be able to generate power. Therefore, in the control of the brake force, first, a brake to be generated by the brake device 12 is obtained by subtracting the regenerative brake force from the necessary total brake force obtained based on the brake operation force detected by the operation force sensor δ _PDL . Force, that is, the required hydraulic brake force _FBL is determined. Then, based on the required hydraulic braking force F _BL, target servo pressure P ^* _SRV is servo pressure P _SRV as a target is determined.

Next, based on the change in the target servo pressure, it is determined whether the current process is a pressure increasing process, a pressure reducing process, or a pressure maintaining process. In the pressure increasing process, as shown in the following formula, the supply current I _R to the pressure reducing linear valve 26 is a pilot that is higher than the pilot pressure P _PLT for realizing the target servo pressure P ^* _SRV by a certain margin. is the degree of current that does not open even pressure P _PLT, the supply current I _a to the pressure-increasing linear valve 24, a current including a feedforward component I _a-FF and the feedback component I _a-FB-based servo pressure P _SRV Is done. The feed-forward component will be described in detail later. The feedback component is obtained by multiplying the servo pressure deviation ΔP _SRV (= P ^* _SRV− P _SRV ) by the pressure increase feedback gain γ _A.
I _A = I _{A -FF} + I _{A -FB} = I _{A -FF} + γ _A · ΔP _SRV (1)
I _R = I _R-EQ + I _R-MAG (2)
Note that I _R-EQ in the above equation is a current at which the pressure reducing linear valve 26 becomes a boundary between the valve open state and the valve closed state (valve opening / closing equilibrium state) at the target servo pressure, that is, a so-called equilibrium current. The value is preset according to the target servo pressure. _IR-MAG is a margin current.

In the decompression process, as shown in the following formula, the supply current I _A to the pressure-increasing linear valve 24 is set to 0, and the supply current I _R to the decompression linear valve 26 is the pressure-increasing linear in the pressure-increasing process. Similar to the supply current I _A to the valve 24, the current includes a feed forward component I _R-FF and a feedback component I _R-FB . Similarly, the feedback component is obtained by multiplying the servo pressure deviation ΔP _SRV by the decompression feedback gain γ _R.
I _A = 0 (3)
_{I R = I R-FF +} I R-FB = I R-FF + γ R · ΔP SRV ··· (4)
In the pressure maintaining process, as shown in the following formula, the supply current to the pressure increasing linear valve 24 is set to 0, and the supply current to the pressure reducing linear valve 26 is the same as in the pressure increasing process. , The current obtained by adding the margin current I _R-MAG to the balanced current I _R-EQ .
I _A = 0 (5)
I _R = I _R-EQ + I _R-MAG (6)

In the vehicle hydraulic brake system (pressure regulation system), whether the preceding process was a pressure increasing process or a pressure reducing process in consideration of the pressure increasing start characteristic and the pressure decreasing start characteristic as described above. Thus, the feedforward component I _A-FF in the supply current I _A of the pressure increasing linear valve 24 is changed. The pressure increase start characteristic as shown in FIG. 5A is acquired in advance. Specifically, when the preceding process is a pressure increasing process, the preceding process is a pressure reducing process according to the forward pressure increasing characteristic. In some cases, the feedforward component I _A-FF is determined according to the reverse pressure-increasing characteristic, as in the following equation.
Prior process = pressure increasing process: I _A-FF = I _A-FF-FW (7)
Prior process = decompression process: I _A-FF = I _A-FF-RV (8)
Similarly, in the pressure reducing process, the feedforward component I _R-FF in the supply current I _R of the pressure reducing linear valve 26 is changed depending on whether the preceding process is a pressure increasing process or a pressure reducing process. The decompression start characteristic as shown in FIG. 5B is acquired in advance. Specifically, when the preceding process is a pressure increasing process, according to the reverse decompression characteristic, the preceding process is a decompressing process. The feedforward component is determined according to the antegrade decompression characteristic as shown in the following equation.
Prior process = pressure increasing process: I _R-FF = I _R-FF-RV (9)
Prior process = decompression process: I _R-FF = I _R-FF-FW (10)
The feedforward components I _A-FF and I _R-FF are changed by changing the supply currents I _A and I _R to the pressure increasing linear valve 24 and the pressure reducing linear valve 26 at the start of the pressure increasing process and the pressure reducing process. The change is made according to the preceding process, and in that sense, it can be considered as a kind of supply current change control.

As described above, the supply currents I _A and I _R are determined. However, when the pressure increasing process or the pressure reducing process is started, the feedback components I _A-FB and I _R-FB hardly exist at the start time. Appropriate supply currents I _A and I _R depending on the preceding process are supplied to the pressure increasing linear valve 24 and the pressure reducing linear valve 26 by the feed forward components I _A-FF and I _R-FF . Further, while the started process continues, not only at the time of starting but also after that, feedforward components I _A-FF and I _R-FF according to either the forward characteristic or the reverse characteristic are output. Although the feedback components I _A-FB and I _R-FB increase to some extent as the process proceeds, the feedforward components I _A-FF and I _R- when the process proceeds to some extent. The difference between the supply currents I _A and I _R due to the difference in _FF is almost eliminated. Accordingly, appropriate supply currents I _A and I _R are supplied to the pressure-increasing linear valve 24 and the pressure-decreasing linear valve 26 until the pressure-increasing process or the pressure-decreasing process is started and ended. .

In the vehicle hydraulic brake system (pressure regulating system), as described above, the feedback gains γ _A and γ _R (pressure-increasing feedback gain γ _A) are taken into consideration in response to the control of the braking force. , A general term for the decompression feedback gain γ _R ) is set by a specific rule, that is, a rule based on the characteristic difference ΔC. Specifically, the larger the increase pressure characteristics gender [Delta] C _A, is set the pressure increasing feedback gain gamma _A large, as the reduced pressure characteristic difference [Delta] C _R is larger, vacuum feedback gain gamma _R is set larger.

ii) Brake Force Control Program The above-described brake force control is performed by the ECU 30 repeatedly executing the brake force control program shown in the flowchart of FIG. 6 at a short time pitch (for example, several tens of μsec). Hereinafter, specific control of the braking force will be described in accordance with the program.

In the processing by the brake force control program, first, the required hydraulic brake force F described above is based on the brake operation force δ _PDL detected by the operation force sensor 52 in S1 (S is an abbreviation for “step”). _BL is determined, then, in S2, based on the required hydraulic braking force F _BL, target servo pressure P ^* _SRV described above is determined. Based on the magnitude relationship between the target servo pressure P ^* _SRV determined by the subsequent determinations of S3 and S4 and the previous target servo pressure P ^* _SRV-PRE that is the target servo pressure P ^* _SRV in the previous execution of the program. It is determined whether the current process is a pressure increasing process, a pressure reducing process, or a pressure maintaining process.

If the current process is a pressure increasing process, steps S5 and the subsequent steps are executed. In the processing by this program, a preceding process indicator PS indicating whether the preceding process is a pressure increasing process or a pressure reducing process is adopted, and the preceding process indicator PS is “1”, and the preceding process is a pressure increasing process. "0" indicates that the preceding process is a decompression process. In S5, based on the value of the preceding process indicator PS, it is determined whether the preceding process is a pressure increasing process or a pressure reducing process. If the preceding process is a pressure increasing process, the pressure increasing linear is determined in S6. The feed forward component I _A-FF of the supply current I _A to the valve 24 is determined to be the forward characteristic dependent component I _A-FF-FW which is a component according to the forward characteristic. On the other hand, if the preceding process is a decompression process, in S7, the feedforward component I _A-FF is determined to be a reverse rotation characteristic dependent component I _A-FF-RV that is a component according to the reverse rotation characteristic. Subsequently, in S8, the feedback component I _A-FB of the supply current I _A to the pressure increasing linear valve 24 is based on the pressure increasing feedback gain γ _A and the servo pressure deviation ΔP _SRV set as described above. In S9, the feedforward component I _A-FF and the feedback component I _A-FB are added to determine the supply current I _A to the pressure-increasing linear valve 24. In S10, the supply current I _R to the pressure-reducing linear valve 26 is determined as the sum of the balanced current I _R-EQ and the margin current I _R-MAG as described above. In the processing by this program, a pressure-increasing process flag Fa indicating whether or not the current process is a pressure-increasing process is adopted, and the pressure-increasing process flag Fa is “1”. It is indicated that “0” is not a pressure increasing process. In S11, the pressure increasing process flag Fa is set to “1”.

On the other hand, if the current process is a decompression process, the steps after S12 are executed. First, in S12, based on the value of the preceding process indicator PS, it is determined whether the preceding process is a pressure increasing process or a depressurizing process. The feedforward component I _R-FF of the supply current I _R to the linear valve 26 is determined as the forward characteristic dependent component I _R-FF-FW . On the other hand, if the preceding process is a pressure increasing process, the feedforward component I _R-FF is determined to be the reverse rotation characteristic dependent component I _R-FF-RV in S14. Subsequently, in S15, the feedback component I _R-FB of the supply current I _R to the pressure reducing linear valve 26 is determined based on the pressure reducing feedback gain γ _R and the servo pressure deviation ΔP _SRV set as described above. In S16, the feedforward component I _R-FF and the feedback component I _R-FB are added to determine the supply current I _R to the pressure-reducing linear valve 26. In S17, the supply current I _A to the pressure-increasing linear valve 24 is determined to be 0 as described above. In the processing by this program, a decompression process flag Fr indicating whether or not the current process is a decompression process is adopted, and the decompression process flag Fr indicates that “1” is a decompression process. “0” indicates that the decompression process is not performed. In S18, the decompression process flag Fr is set to “1”.

Further, when the current process is a pressure maintaining process, the processes of S19 and subsequent steps are executed. The processing of S19 to 23 is based on the pressure increasing process flag Fa and the pressure reducing process flag Fr as to whether the preceding process is started, that is, whether the preceding process is a pressure increasing process or a pressure reducing process. Is recognized and set in the above-described preceding process indicator PS. These processes can be considered as processes that are performed only once when the pressure maintenance process is started. Subsequently, as described above, in S24, the supply current I _A to the pressure increasing linear valve 24 is 0, and in S25, the supply current I _R to the pressure reducing linear valve 26 is as described above. It is determined as the sum of the balanced current I _R-EQ and the margin current I _R-MAG .

After executing a series of processes for any of the pressure increasing process, the pressure reducing process, and the pressure maintaining process, in S26, the current target servo pressure P ^* _SRV is set as the previous target servo pressure P ^* _SRV-PRE , and the program One execution is completed.

[D] Acquisition of pressure regulation characteristics
i) Overview of pressure regulation characteristic acquisition method The pressure regulation characteristic in the pressure regulation system, more specifically, the pressure increase start characteristic and the pressure reduction start characteristic are determined by the pressure regulation system, that is, the vehicle hydraulic brake system. For each mounted vehicle, this is performed before the vehicle is shipped. The pressure regulation characteristic acquisition method of the embodiment roughly includes (a) a pressure increase start pressure P _SRV-AS that is a servo pressure P _SRV at the time when the pressure increase process is started, and a pressure increase linear valve 24 at that time. the supply current I _a at a pressure boosting starting current I _aS, and increasing pressure characteristic acquisition step of acquiring the pressure boosting starting pressure P _SRV-aS sequentially changed while the, (b) depressurizing process is beginning to sequentially changing the pressure-decrease start pressure P _SRV-RS is a servo pressure P _SRV, and a pressure-decrease start current I _RS is the supply current I _R of the pressure reducing linear valve 26 at that time, the pressure-decrease start pressure P _SRV-RS in And a decompression characteristic acquisition step that is acquired.

  The boosting characteristic acquisition step roughly includes a forward boosting characteristic acquisition step for acquiring the above-described forward boosting characteristic, which is a boosting start characteristic when the preceding process is a boosting process, and a preceding process. Can be divided into the above-described reverse pressure-increasing characteristic acquisition step for acquiring the above-mentioned reverse pressure-increasing characteristic, which is a pressure-increasing start characteristic when the pressure-decreasing process is in progress. The forward pressure reduction characteristic acquisition step for acquiring the above-mentioned forward pressure reduction characteristic that is the pressure reduction start characteristic in the case of the pressure reduction process, and the above-described reverse pressure reduction characteristic that is the pressure reduction start characteristic when the preceding process is the pressure increase process It can be divided into a reverse pressure-increasing characteristic acquisition step for acquiring. However, the antegrade pressure increase characteristic acquisition step and the antegrade pressure reduction characteristic acquisition step are performed independently, but the reverse pressure increase characteristic acquisition step and the reverse pressure decrease characteristic acquisition step are reverse rotations in which they are all united. This is performed as a characteristic acquisition step. Hereinafter, the antegrade pressure increase characteristic acquisition step, antegrade pressure reduction characteristic acquisition step, and reverse rotation characteristic acquisition step will be described in detail.

ii) Forward pressure increase characteristic acquisition step FIG. 7 shows the servo pressure P _SRV in the forward pressure increase characteristic acquisition step and the forward pressure reduction characteristic acquisition step, and the supply current I _A to the pressure increase linear valve 24 and the pressure reduction linear valve 26. , I _R. The left part of the graph shows the antegrade pressure increase characteristic acquisition step, and the right part shows the antegrade pressure reduction characteristic acquisition step. With reference to this graph, the antegrade pressure increase characteristic acquisition step will be described. In this step, first, the pressure increase linear valve 24 is opened while the pressure decrease linear valve 26 is closed, and the pressure increase process. After realizing the above, the pressure-increasing valve maintaining step for closing the pressure-increasing linear valve 24 is performed. In this pressure increase closing valve maintaining step, the maximum current I _R-MAX set in the pressure adjusting system is supplied to the pressure reducing linear valve 26, and the pressure increasing linear valve 24 is set in the pressure adjusting system. The maximum current I _A-MAX is supplied for a short time. Thereafter, the supply current I _A to the pressure increasing linear valve 24 is set to zero. By this pressure increasing and closing valve maintaining step, the spool 84 is positioned at a position moved from the locking position to the other end side by the predetermined distance L. After completion of the increasing pressure closed valve maintaining step, for the purpose of reducing power consumption, the supply current I _R of the pressure-reducing linear valve 26, the supply current I _R that is when the servo pressure P _SRV normal range without opening _Is lowered to the holding current I _R-HOLD set as.

In the antegrade pressure increase characteristic acquisition step, a plurality of antegrade pressure increase acquisition steps are continuously performed after the pressure increase closing valve maintaining step. In each forward pressure increase acquisition step, in order to open the pressure increase linear valve 24, the supply current I _A to the pressure increase linear valve 24 is gradually changed (specifically, gradually increased), and the change is in progress. in at the time the pressure increasing process is started, that is, at the time when the servo pressure P _SRV starts to rise, the servo pressure P _SRV at that time as the pressure boosting starting pressure P _SRV-aS, at the time the pressure-increasing linear valve 24 Supply current I _A is acquired as a pressure increase start current I _AS . Incidentally, the maximum current I _R-MAX is supplied to the pressure-reducing linear valve 26 while the acquisition step at each forward pressure increase is performed. In each antegrade pressure increase acquisition step, the gradual change of the supply current I _A to the pressure increase linear valve 24 is continued for a set time after the pressure increase process is started, whereby the antegrade pressure increase acquisition step to be performed next is performed. pressure boosting starting pressure P _SRV-aS to be obtained is high, so that the pressure increase starting current I _aS increases in. By performing a plurality of such acquisition steps at the time of antegrade pressure increase, in the antegrade pressure increase characteristic acquisition step, the pressure increase start pressure _PSRV-AS is sequentially changed and a plurality of pairs are increased step by step. The pressure start pressure P _SRV-AS and the pressure increase start current I _AS are sequentially acquired. Note that the spool 84 does not move the predetermined distance L and return to the locking position while the plurality of forward pressure increasing acquisition steps are performed.

iii) Forward pressure reduction characteristic acquisition step The forward pressure reduction characteristic acquisition step will be described. In this step, first, the pressure reduction linear valve 26 is opened while the pressure increase linear valve 24 is closed, and the pressure reduction process is performed. After the realization, a pressure reduction closed valve maintaining step for closing the pressure reduction linear valve 26 is performed. In this pressure reducing valve closing maintaining step, in a state where the supply current I _A to the pressure increasing linear valve 24 is set to 0, the supply current I _R to the pressure reducing linear valve 26 is set to 0 for a short time, and then the supply current I _R is the maximum current I _R-MAX . The spool 84 is positioned at the locking position by this reduced pressure valve closing maintaining step.

In the forward pressure reduction characteristic acquisition step, a plurality of forward pressure reduction acquisition steps are successively performed after the above-described pressure reduction valve closing maintaining step. In each anterograde vacuum during acquisition step, the pressure-reducing linear valve 26 so as to open the vacuum graded the supply current I _R to the linear valve 26 (more specifically a is gradually decreased) to its grading middle pressure reduction process in the time but has started, that is, at the time when the servo pressure P _SRV starts to descend, the supply current I _R of the servo pressure P _SRV at that time as the start of evacuation pressure P _SRV-RS, the pressure-reducing linear valve 24 at that time Are obtained as the decompression start current I _RS . Incidentally, the supply current I _A is not supplied to the pressure-increasing linear valve 24 during each forward pressure reduction acquisition step. In each anterograde vacuum during acquisition step, is obtained in the graded to be to continue the set time, then anterograde vacuum at acquisition steps performed of the supply current I _R of the pressure-reducing linear valve 26 after the vacuum process has started The pressure reduction start pressure P _SRV-RS is low, and the pressure reduction start current I _RS is small. By performing a plurality of such antegrade pressure reduction acquisition steps in succession, in the antegrade pressure reduction characteristic acquisition step, the pressure reduction start pressure _PSRV-RS is sequentially changed, and a plurality of pairs of pressure reduction start pressures P are stepwise. _SRV-RS and decompression start current I _RS are sequentially acquired. It should be noted that the spool 84 does not move the predetermined distance L from the locking position to the other end side while a plurality of forward decompression acquisition steps are being performed.

iv) Reverse rotation characteristic acquisition step FIG. 8 is a graph showing changes in the servo pressure P _SRV and the supply currents I _A and I _R to the pressure-increasing linear valve 24 and the pressure-reducing linear valve 26 in the reverse rotation characteristic acquisition step. The reverse rotation characteristic acquisition step is a step in which the reverse pressure increase characteristic acquisition step and the reverse pressure reduction characteristic acquisition step are integrated. More specifically, in the reverse rotation characteristic acquisition step, a plurality of reverse pressure increase acquisition steps constituting the reverse pressure increase characteristic acquisition step and a plurality of reverse pressure reduction pressure acquisition steps constituting the reverse pressure reduction characteristic acquisition step are alternately repeated. Is done by.

In one reverse pressure increase acquisition step, the pressure reducing linear valve 26 is opened while the pressure increasing linear valve 24 is closed to realize the pressure reducing process, and then the pressure reducing linear valve 26 is closed and closed. In order to open the pressure-increasing linear valve 24 after the valve, the supply current I _A to the pressure-increasing linear valve 24 is gradually changed (specifically, gradually increased), and the pressure-increasing process is started in the middle of the gradually changing. At the time, the servo pressure P _SRV is acquired as the pressure increase start pressure P _SRV-AS and the supply current I _A to the pressure increase linear valve 24 is acquired as the pressure increase start current I _AS . On the other hand, in one reverse pressure reduction acquisition step, the pressure increasing linear valve 24 is opened while the pressure reducing linear valve 26 is closed to realize the pressure increasing process, and then the pressure increasing linear valve 24 is closed. In order to open the pressure-reducing linear valve 26 after the valve closing, the supply current I _R to the pressure-reducing linear valve 26 is gradually changed (specifically, gradually reduced), and the pressure-reducing process is started in the middle of the gradually changing. at time, the servo pressure P _SRV as vacuum starting pressure P _SRV-RS, the supply current I _R of the pressure reducing linear valve 26 as a pressure reducing starting current I _RS, to obtain.

More specifically, the section “A” in the graph of FIG. 8 is an acquisition step at the time of reverse pressure increase, and the section “B” is an acquisition step at the time of reverse pressure reduction. This reverse rotation characteristic acquisition step starts from the reverse rotation pressure reduction acquisition step. In the acquisition step at the time of reverse pressure reduction, first, the holding current I _R-HOLD is supplied to the pressure reducing linear valve 26 to close the pressure reducing linear valve 26, and the supply current I _A to the pressure increasing linear valve 24 is The servo pressure _PSRV is gradually increased until it reaches a predetermined pressure. Thereby, the pressure increasing process is realized. When the servo pressure P _SRV reaches a predetermined pressure, the supply current I _A is started to gradually decrease, whereby the servo pressure P _SRV is maintained at the predetermined pressure. Thereafter, the supply current I _R is is gradually decreased to the pressure-reducing linear valve 26, in a section "b" in FIG. 8, the spool 84 is moved up to the locking position of the one end side of the movable range. During the gradual decrease of the supply current I _R , the servo pressure P _SRV starts to decrease, and the pressure reducing process is started. As the servo pressure P _SRV time of starting pressure reduction starting pressure P _SRV-RS, is the supply current I _R at the time of the start is acquired as a pressure reducing starting current I _RS. In the meantime, the supply current I _A to the pressure increasing linear valve 24 continues to gradually decrease so that the pressure increasing linear valve 24 does not open.

In the subsequent reverse pressure-increasing acquisition step, the supply current I _A to the pressure-increasing linear valve 24 is continuously decreased while the valve-closing state of the pressure-increasing linear valve 24 is maintained. On the other hand, the supply current I _R to the pressure-reducing linear valve 26 is also continuously reduced, but the supply current I _R is gradually increased when the servo pressure P _SRV becomes a predetermined pressure different from the predetermined pressure, After a while, the current is rapidly increased to the holding current _IR-HOLD . At the timing when the holding current I _R-HOLD is supplied, the supply current I _A to the pressure-increasing linear valve 24 is gradually increased, and in the section “a” in FIG. It is moved to the other end side by a predetermined distance L. During the gradual increase of the supply current I _A , the servo pressure P _SRV starts to rise and the pressure increasing process is started. The servo pressure P _SRV at the start time is acquired as the pressure increase start pressure P _{SRV-AS and} the supply current I _A at the start time is acquired as the pressure increase start current I _AS . Thereafter, the acquisition step at the time of reverse pressure reduction and the acquisition step at the time of reverse pressure increase are alternately and continuously performed.

v) Creation of pressure increase start characteristic, pressure reduction start characteristic, etc. The pressure increase start pressure P _SRV when the preceding process is a pressure increase process is determined by the forward pressure increase characteristic acquisition step and the forward pressure decrease characteristic acquisition step described above, respectively. _-AS and pressure boosting starting current I _aS, pressure-decrease start pressure P _SRV-RS and decompression starting current I _RS when the preceding process are vacuum process, a plurality of increasing pressure-opening start point is obtained at the start of evacuation point. Further, in the reverse rotation characteristic acquisition step, the pressure increase start pressure P _SRV-AS and the pressure increase start current I _AS when the preceding process is the pressure reducing process, and the pressure decrease start pressure P _SRV-RS when the preceding process is the pressure increasing process. The pressure reduction start current I _RS is acquired at a plurality of pressure increase start points and pressure reduction start points. The data of the pressure increase start point and the pressure decrease start point are discrete data. Based on the data, for example, linear interpolation processing or the like is performed, and the pressure regulation characteristic unique to the pressure regulation system, that is, The forward pressure increasing characteristic and the reverse pressure increasing characteristic as shown by the characteristic line are created in 5 (a), and the forward pressure reducing characteristic and the reverse pressure reducing characteristic as shown by the characteristic line in FIG. 5 (b) are created.

  The forward pressure increase characteristic acquisition step, the forward pressure reduction characteristic acquisition step, and the reverse rotation characteristic acquisition step may be performed only once, or may be performed a plurality of times by changing the pressure increase start pressure and the pressure decrease start pressure. By performing a plurality of times and acquiring data of a large number of pressure increase start points and pressure decrease start points, more accurate pressure regulation characteristics can be obtained.

[E] Modification
i) Control and pressure regulation characteristics considering pressure change of high-pressure source As described above, the pressure of the hydraulic fluid supplied from the high-pressure source device 20, that is, the accumulator pressure P _ACC fluctuates within a certain range. On the other hand, differential pressure acting force F _P of the pressure-increasing linear valve 24 is dependent on the difference between the accumulator pressure P _ACC and the pilot pressure P _PLT, control of the servo pressure P _SRV, that is, control of the braking force is increased In the pressure process, the accuracy can be further increased by considering the accumulator pressure P _ACC . From this point of view, the feedforward component I _A-FF of the supply current I _A to the pressure increasing linear valve 24 in the pressure increasing process can be determined according to the following equation.
I _A-FF = α · (P _ACC −P _PLT ) = α (P _ACC −P ^* _SRV / R _P0 ) (11)
Here, α is a feed forward gain, and R _P0 is the theoretical pressure regulation ratio of the regulator 22 described above. Incidentally, the difference between the accumulator pressure P _ACC and the pilot pressure P _PLT may be simply referred to as a differential pressure ΔP _ACC-PLT .

When the feedforward component I _A-FF is determined as described above, the forward pressure increasing characteristic and the reverse pressure increasing characteristic in the pressure increasing process are the servo pressure P _SRV and the supply current I to the pressure increasing linear valve 24. relationship between _a, speaking in detail, rather than the relationship between the pressure boosting starting pressure P _SRV-aS and the pressure boosting starting current I _aS, the pressure difference [Delta] P _ACC-PLT and the pressure boosting starting at the time the pressure increasing process is started it is desirable to obtain as the relationship between the current I _aS. When such a relationship is acquired, the pressure increase start pressure P _SRV-AS acquired at the time when the pressure increase process is started, the accumulator pressure P _ACC detected by the accumulator pressure sensor 68 at that time, and the above-mentioned Based on the theoretical pressure regulation ratio R _P0 , a differential pressure ΔP _ACC-PLT at that time, that is, a pressure increase start differential pressure ΔP _ACC-PLT - _S is obtained, and the pressure increase start differential pressure ΔP _ACC-PLT - _S based on the pressure increase starting current I _aS at that time, anterograde increase pressure characteristics may be creating a reversal increase pressure characteristics. Since the differential pressure ΔP _ACC-PLT can be considered as the servo pressure P _SRV corrected based on the accumulator pressure P _ACC , the forward pressure increase characteristic and the reverse pressure increase characteristic also have the pressure increase start pressure. This can be regarded as a relationship between P _SRV-AS and the pressure increase start current I _AS .

In addition, although detailed explanation is omitted, the forward pressure reduction characteristics and the reverse pressure reduction characteristics are similar to the forward pressure increase characteristics and the reverse pressure increase characteristics, and the pressure difference between the atmospheric pressure P _ATM and the pilot pressure P _PLT is reduced. It can also be created as a relationship with the starting current I _RS .

ii) Others In the above embodiment, in controlling the braking force,
(a) Supply current I _A to the pressure-increasing linear valve 24 at the start of the pressure-increasing process and supply current I _R to the pressure-decreasing linear valve 26 at the start of the pressure-decreasing process, more specifically, their feedforward components I _{A− Switching FF} and I _R-FF depending on whether the preceding process is a pressure increasing process or a pressure reducing process;
(b) Boosting the feedback gains γ _A and γ _R for determining the feedback components I _A-FB and I _R-FB of the currents I _A and I _R supplied to the pressure-increasing linear valve 24 and the pressure-reducing linear valve 26 Although both the characteristic difference and the value corresponding to the pressure reduction characteristic difference are set, only either (a) or (b) may be performed.

In the case of performing the above (a), only one of the supply current I _A to the pressure-increasing linear valve 24 and the supply current I _R to the pressure-decreasing linear valve 26 is applied in the pressure-increasing process or in the pressure-increasing process. It may be switched depending on whether it exists. In the case of performing the above (b), only one of the pressure increase feedback gain γ _A for the pressure increase linear valve 24 and the pressure decrease feedback gain γ _R for the pressure decrease linear valve 26 is set to a pressure increase characteristic difference or pressure decrease. You may set to the value according to the characteristic difference.

12: Brake device 16: Master cylinder device 18: Brake pedal [brake operating member] 20: High pressure source device [high pressure source] 22: Regulator [pressure regulator] 24: Pressure increasing linear valve 26: Pressure reducing linear valve 28: Reservoir [low pressure] Source] 30: Electronic control unit (ECU) [Control device] 66: Accumulator 80: Spool valve mechanism 84: Spool 108: Return spring 112: Servo pressure sensor R4: First pilot pressure chamber [Pilot pressure chamber] R6: Pressure regulation Chamber P1: High pressure port P2: Low pressure port P3: Pressure adjustment port P _ACC : Accumulator pressure P _PLT : Pilot pressure P _SRV : Servo pressure [supply pressure] P _SRV-AS : Increase pressure start pressure P _SRV-RS : Pressure _decrease start pressure I _A : Supply current I _A-FF : Feed forward component I _A-FB : Feedback component I _AS : Boosting start current I _R : Supply Supply current I _R-FF : Feed forward component I _R-FB : Feedback component I _RS : Decompression start current γ _A : Boosting feedback gain γ _R : Depressurization feedback gain ΔC _A : Boosting characteristic difference ΔC _R : Depressurization characteristic difference L : Predetermined distance

Claims (11)

(a) a high-pressure port for receiving hydraulic fluid from a high-pressure source, (b) a low-pressure port for discharging hydraulic fluid to a low-pressure source, and (c) a pressure regulator for supplying pressure-controlled hydraulic fluid A port; (d) a pressure regulating chamber into which the pressure-adjusted hydraulic fluid is introduced; (e) a pilot pressure chamber into which hydraulic fluid that serves as a pilot pressure is introduced; and (f) a hydraulic fluid in the pressure regulating chamber. And a spool that is biased to the other end side by the pressure of the hydraulic fluid in the pilot pressure chamber, and the spool is located at a specific position on one end side of the movable range, When the low pressure port communicates with the pressure regulation port and the communication between the high pressure port and the pressure regulation port is interrupted, and the spool moves a predetermined distance from the specific position to the other end side in the movable range, Block communication between the low pressure port and the pressure regulating port And said high pressure port and the pressure regulating port and the spool valve mechanism and a comprise constituted a pressure regulator for communicating with,
An electromagnetic pressure increasing linear valve and a pressure reducing linear valve connected to the pilot pressure chamber in order to adjust the pressure of the hydraulic fluid in the pilot pressure chamber;
By controlling the supply current to the pressure-increasing linear valve in the pressure-increasing process and the current to be supplied to the pressure-decreasing linear valve in the pressure-decreasing process, the pilot pressure is adjusted, and the hydraulic fluid supplied from the pressure regulator A pressure control system comprising: a control device that adjusts a supply pressure that is a pressure of the pressure to a pressure corresponding to the adjusted pilot pressure;
The control device is
At least one of a pressure increase start current that is a supply current to the pressure increasing linear valve at the start of the pressure increasing process and a pressure decrease start current that is a supply current to the pressure reducing linear valve at the start of the pressure reducing process. , Configured to execute supply current change control that changes depending on whether the preceding process, which is one of the pressure increasing process and the pressure reducing process performed before those processes, is a pressure increasing process or a pressure reducing process Pressure regulation system.   The pressure regulating system according to claim 1, wherein the control device is configured to execute the supply current change control with respect to both the pressure increase start current and the pressure decrease start current. The control device is
The supply current to the pressure-increasing linear valve in the pressure-increasing process and the supply current to the pressure-decreasing linear valve in the pressure-decreasing process are configured to control a supply current including a feedforward component based on the supply pressure,
When configured to execute the supply current change control on the pressure increase start current, the control device uses the feedforward component of the pressure increase start current, and the preceding process is a pressure increase process. Is configured to change depending on whether it is a decompression process,
When configured to execute the supply current change control on the pressure reduction start current, the control device uses the feedforward component of the pressure reduction start current, and the preceding process is a pressure increase process. The pressure regulation system according to claim 1 or 2, wherein the pressure regulation system is configured to change depending on whether the pressure reduction process is performed. The relationship between the pressure increase start current and the supply pressure is defined as the pressure increase start characteristic, and the relationship between the pressure decrease start current and the supply pressure is defined as the pressure decrease start characteristic, respectively, and the preceding process is a pressure increase process. Pressure increase start characteristic in a certain case, forward pressure increase characteristic, pressure increase start characteristic in the case where the preceding process is a pressure reduction process, reverse pressure increase characteristic, and pressure reduction start in the case where the preceding process is a pressure reduction process In the case where the characteristic is defined as an antegrade pressure reduction characteristic and the pressure reduction start characteristic when the preceding process is a pressure increase process, a reverse pressure reduction characteristic,
When the control device is configured to execute the supply current change control with respect to the pressure increase start current, the control device acquires the forward pressure increase characteristic and the reverse rotation that are acquired in advance. Determining the feedforward component according to an alternative to the pressure boosting characteristic;
When the control device is configured to execute the supply current change control with respect to the pressure reduction start current, the control device acquires the forward pressure reduction characteristics and the reverse pressure reduction characteristics acquired in advance. 4. The pressure regulating system according to claim 3, wherein the pressure regulating system is configured to determine the feedforward component according to an alternative. The relationship between the pressure increase start current and the supply pressure is defined as the pressure increase start characteristic, and the relationship between the pressure decrease start current and the supply pressure is defined as the pressure decrease start characteristic, respectively, and the preceding process is a pressure increase process. Pressure increase start characteristic in a certain case, forward pressure increase characteristic, pressure increase start characteristic in the case where the preceding process is a pressure reduction process, reverse pressure increase characteristic, and pressure reduction start in the case where the preceding process is a pressure reduction process In the case where the characteristic is defined as an antegrade pressure reduction characteristic and a pressure reduction start characteristic when the preceding process is a pressure increase process, a reverse pressure reduction characteristic, respectively,
The control device is configured to control a supply current including a feedback component based on the supply pressure as a supply current to the pressure-increasing linear valve in the pressure-increasing process and a supply current to the pressure-decreasing linear valve in the pressure-decreasing process. ,
A pressure-increasing feedback gain that is a feedback gain for determining a feedback component of a supply current to the pressure-increasing linear valve, and a pressure-reduction feedback gain that is a feedback gain for determining a feedback component of a current that is supplied to the pressure-reducing linear valve Are set according to specific rules,
When the pressure increase feedback gain is set according to the specific rule, the specific rule indicates that the pressure increase feedback gain has a magnitude corresponding to the difference between the forward pressure increase characteristic and the reverse pressure increase characteristic. It is a rule that becomes
When the decompression feedback gain is set according to the specific rule, the specific rule is such that the decompression feedback gain has a magnitude corresponding to a difference between the forward decompression characteristic and the reverse decompression characteristic. The pressure regulating system according to any one of claims 1 to 4, wherein the pressure regulating system is a rule.   The pressure regulation system according to claim 5, wherein both the pressure-increasing feedback gain and the pressure-reducing feedback gain are set according to the specific rule. A brake operating member operated by a driver;
A brake device provided on the wheel for generating a braking force;
The pressure adjusting system according to any one of claims 1 to 6 and a hydraulic fluid adjusted in pressure by the pressure regulator are introduced, and the hydraulic fluid is added to a pressure corresponding to the pressure of the introduced hydraulic fluid. A master cylinder device that pressurizes and supplies the pressurized hydraulic fluid to the brake device;
With
The control device controls the supply current to the pressure-increasing linear valve in the pressure-increasing process and the current to the pressure-decreasing linear valve in the pressure-decreasing process in accordance with the operation of the brake operation member. A vehicle hydraulic brake system configured to control a braking force to be generated. (a) a high-pressure port for receiving hydraulic fluid from a high-pressure source, (b) a low-pressure port for discharging hydraulic fluid to a low-pressure source, and (c) a pressure regulator for supplying pressure-controlled hydraulic fluid A port; (d) a pressure regulating chamber into which the pressure-adjusted hydraulic fluid is introduced; (e) a pilot pressure chamber into which hydraulic fluid that serves as a pilot pressure is introduced; and (f) a hydraulic fluid in the pressure regulating chamber. And a spool that is biased to the other end side by the pressure of the hydraulic fluid in the pilot pressure chamber, and the spool is located at a specific position on one end side of the movable range, When the low pressure port communicates with the pressure regulation port and the communication between the high pressure port and the pressure regulation port is interrupted, and the spool moves a predetermined distance from the specific position to the other end side in the movable range, Block communication between the low pressure port and the pressure regulating port And said high pressure port and the pressure regulating port and the spool valve mechanism and a comprise constituted a pressure regulator for communicating with,
An electromagnetic pressure increasing linear valve and a pressure reducing linear valve connected to the pilot pressure chamber in order to adjust the pressure of the hydraulic fluid in the pilot pressure chamber;
By controlling the supply current to the pressure-increasing linear valve in the pressure-increasing process and the current to be supplied to the pressure-decreasing linear valve in the pressure-decreasing process, the pilot pressure is adjusted, and the hydraulic fluid supplied from the pressure regulator And a control device that adjusts the supply pressure, which is the pressure of the pressure, to a pressure corresponding to the adjusted pilot pressure, the supply current to the pressure-increasing linear valve at the start of the pressure-increasing process A pressure increase start characteristic that is a relationship between a certain pressure increase start current and the supply pressure, and a pressure decrease that is a relationship between the pressure decrease start current that is a supply current to the pressure reducing linear valve at the start of the pressure reduction process and the supply pressure A pressure regulation characteristic acquisition method for acquiring at least one of a start characteristic,
The pressure increase start pressure is sequentially changed between the pressure increase start pressure that is the supply pressure at the time when the pressure increase process is started and the supply current to the pressure increase linear valve at that time as the pressure increase start current. However, a pressure increase characteristic acquisition step for acquiring a case where the preceding process, which is one of the pressure increasing process and the pressure reducing process performed before the pressure increasing process, is a pressure reducing process,
The pressure reduction start pressure, which is the supply pressure at the time when the pressure reduction process is started, and the supply current to the pressure reduction linear valve at that time as the pressure reduction start current, while sequentially changing the pressure reduction start pressure, the preceding pressure A pressure regulation characteristic acquisition method comprising: at least one of a pressure reduction characteristic acquisition step acquired when the process is a pressure increase process.   The pressure regulation characteristic acquisition method according to claim 8, comprising both the pressure increase characteristic acquisition step and the pressure reduction characteristic acquisition step, and acquiring both the pressure increase start characteristic and the pressure reduction start characteristic. The pressure increase characteristic acquisition step includes:
After the pressure increasing linear valve is closed, the pressure reducing linear valve is opened to realize a pressure reducing process, and then the pressure reducing linear valve is closed, and after the valve closing, the pressure increasing linear valve is opened. In order to make the valve, the supply current to the pressure-increasing linear valve is gradually changed, and when the pressure-increasing process starts in the middle of the change, the supply pressure is used as the pressure-increasing start pressure to the pressure-increasing linear valve. Including a plurality of reverse pressure increase acquisition steps to acquire each of the supply current as the pressure increase start current,
The decompression characteristic acquisition step comprises:
After the pressure-reducing linear valve is closed, the pressure-increasing linear valve is opened to realize the pressure-increasing process, and then the pressure-increasing linear valve is closed. In order to open the valve, the supply current to the pressure-reducing linear valve is gradually changed, and when the pressure-reduction process starts in the middle of the change, the supply pressure is set as the pressure-reduction starting pressure. Including a plurality of reverse decompression acquisition steps to obtain each as a decompression start current,
The pressure regulation characteristic acquisition method according to claim 9, wherein the reverse pressure increase acquisition step and the reverse pressure reduction acquisition step are alternately and continuously performed. In the step of acquiring pressure increase characteristics,
The pressure increase start pressure is sequentially changed between the pressure increase start pressure that is the supply pressure at the time when the pressure increase process is started and the supply current to the pressure increase linear valve at that time as the pressure increase start current. However, even when the preceding process was a pressure increasing process,
In the decompression characteristic acquisition step,
The pressure reduction start pressure, which is the supply pressure at the time when the pressure reduction process is started, and the supply current to the pressure reduction linear valve at that time as the pressure reduction start current, while sequentially changing the pressure reduction start pressure, the preceding pressure The pressure regulation characteristic acquisition method according to any one of claims 8 to 10, wherein the process is acquired even when the process is a pressure reduction process.

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