JP2006103440A - Anti-lock brake controlling device of vehicle - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an anti-lock brake controlling device for a vehicle equipped with inlet valves formed as a linear solenoid valve of normally open type and interposed between a hydraulic pressure generating means to emit a hydraulic pressure according to the operation of a brake operating member and the wheel brakes, a current feed control element to control the current feed from a DC power supply to coils, and a control unit able to put the inlet valves in duty control in the half opened condition while operation is made in the boosting mode at the time of anti-lock brake control and to control the current feed control element, whereby capable of eliminating an increase in the boosting speed according to the time elapse at the time of duty control of the inlet valves in the boosting mode. <P>SOLUTION: The control unit controls the current feed control element to the side of increasing the current feed amount to the coils more after the specified time since the boosting mode was started than till elapse of the specified time when the duty control is executed with the inlet valves put in the half opened condition in the boosting mode. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention is configured as a normally-open linear solenoid valve that enables duty control in a half-open state between fully open and fully closed according to changes in the amount of current supplied to the coil, and for operation of a brake operation member. A hydraulic pressure generating means for outputting a corresponding hydraulic pressure, an inlet valve interposed between the wheel brakes, an energization control element for controlling energization from the DC power source to the coil, and a pressure increasing mode during anti-lock brake control Then, the present invention relates to a vehicle antilock brake control device including a control unit that enables duty control of the inlet valve in a half-open state and controls the energization control element.

Such an anti-lock brake control device is already known, for example, from Patent Document 1.
JP 2003-45718 A

  However, in the above-described conventional one, when the duty control is performed on the inlet valve, which is a normally open linear solenoid valve, in the pressure increasing mode, the energization control element is controlled so that the energization amount to the coil becomes constant. However, when the energization state of the coil of the inlet valve continues, the energization current to the coil decreases due to the increase of the resistance value due to the heat generation of the coil, and the opening degree of the inlet valve changes, and the pressure increasing speed is increased. Pressure pulsation may occur due to a sudden increase in pressure due to acceleration.

  The present invention has been made in view of such circumstances, and an anti-lock brake control device for a vehicle in which the pressure increasing speed is not increased with the passage of time during duty control of the inlet valve in the pressure increasing mode. The purpose is to provide.

  In order to achieve the above object, the present invention is configured as a normally open type linear solenoid valve that enables duty control in a half-open state between fully open and fully closed in accordance with changing the energization amount to the coil. A hydraulic pressure generating means for outputting a hydraulic pressure corresponding to the operation of the brake operating member, an inlet valve interposed between the wheel brakes, an energization control element for controlling energization from the DC power source to the coil, In a pressure-increasing mode during lock brake control, the anti-lock brake control device for a vehicle includes a control unit that controls the energization control element so that the inlet valve can be duty controlled in a half-open state. When duty control is performed with the inlet valve in a half-open state in the pressure increasing mode, a predetermined time has elapsed since the start of the pressure increasing mode. During than until the elapsed and controlling the energization control elements on the side to increase the power supply amount to the coil.

  According to such a configuration of the invention, when duty control is performed with the inlet valve in the half-open state in the pressure increasing mode during anti-lock brake control, the predetermined time has elapsed after the predetermined time has elapsed since the start of the pressure increasing mode. Since the energization control element is controlled to increase the energization amount to the coil than before, it is possible to avoid a decrease in the energization current due to an increase in the resistance value due to heat generation of the coil, and the opening of the inlet valve It is possible to prevent the pressure pulsation from occurring by preventing the pressure increase rate from being increased by preventing the pressure from increasing.

  DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiments of the present invention will be described below based on one embodiment of the present invention shown in the accompanying drawings.

  1 to 5 show an embodiment of the present invention, FIG. 1 is a brake hydraulic circuit diagram of a brake device for a passenger vehicle, FIG. 2 is a longitudinal sectional view of an inlet valve, and FIG. 3 is a stroke of a valve shaft. FIG. 4 is a diagram showing a configuration of an inlet valve driving device, and FIG. 5 is a diagram showing an example of a command signal to the inlet valve during antilock brake control.

  First, in FIG. 1, a tandem master cylinder M that is a hydraulic pressure generating means includes first and second output ports that generate brake hydraulic pressure in accordance with a pedaling force applied by a vehicle driver to a brake pedal P that is a brake operating member. 1 and 2 between the first output hydraulic pressure path 3 connected to the first output port 1 and the left front wheel brake BA and the right rear wheel brake BB. VB between the second output hydraulic pressure path 4 connected to the second output port 2 and the right front wheel brake BC and the left rear wheel brake BD, respectively. , VD are provided respectively.

  The hydraulic pressure control valve means VA to VD respectively include inlet valves 5A to 5D individually corresponding to the left front wheel brake BA, the right rear wheel brake BB, the right front wheel brake BC, and the left rear wheel brake BD. And check valves 7A to 7D connected in parallel to the respective inlet valves 5A to 5D, and outlet valves 6A to 6D individually corresponding to the respective wheel brakes BA to BD. It is an open type linear solenoid valve, and the outlet valves 6A to 6D are normally closed type solenoid valves.

  The inlet valves 5A, 5B corresponding to the first output hydraulic pressure path 3 are interposed between the first output hydraulic pressure path 3 and the left front wheel brake BA and the right rear wheel brake BB. The outlet valves 6A and 6B corresponding to the first output hydraulic pressure path 3 include a single first reservoir 8A corresponding to the first output hydraulic pressure path 3, a left front wheel brake BA and a right rear wheel brake. It is interposed between BB. The first reservoir 8A is connected to the suction side of the first pump 10A through which the brake fluid can be pumped from the first reservoir 8A via the first suction valve 9A, and the discharge side of the first pump 10A is connected to the first discharge valve 11A and the first discharge valve 11A. The first output hydraulic pressure path 3 is connected to the first damper 12A.

  The inlet valves 5C and 5D corresponding to the second output hydraulic pressure path 4 are interposed between the second output hydraulic pressure path 4 and the right front wheel brake BC and the left rear wheel brake BD. The outlet valves 6C and 6D corresponding to the second output hydraulic pressure path 4 include a single second reservoir 8B corresponding to the second output hydraulic pressure path 4, a right front wheel brake BC and a left rear wheel brake. It is interposed between BDs. A suction side of a second pump 10B capable of pumping brake fluid from the second reservoir 8B is connected to the second reservoir 8B via a second suction valve 9B, and a discharge side of the second pump 10B is connected to the second discharge valve 11B and the second reservoir 8B. It is connected to the second output hydraulic pressure path 4 via the 2 damper 12B.

  The check valves 7A to 7D are connected in parallel to the inlet valves 5A to 5D so as to allow the flow of brake fluid from the corresponding wheel brakes BA to BD to the master cylinder M.

  The operations of the hydraulic pressure control valve means VA to VD, that is, the operations of the inlet valves 5A to 5D and the outlet valves 6A to 6D, and the operations of the first and second pumps 10A and 10B are controlled by the control unit C. The

  Each of the hydraulic control valve means VA to VD communicates between the master cylinder M and the wheel brakes BA to BD and the wheel brakes BA to BD by the control unit C during normal braking in which each wheel is not likely to be locked. And it controls to the state which interrupts | blocks between the reservoirs 8A and 8B. That is, the outlet valves 6A to 6A are closed by non-energization, and the inlet valves 5A to 5A are opened by non-energization, and the brake fluid output from the first output port 1 of the master cylinder M. The pressure acts on the left front wheel wheel brake BA via the inlet valve 5A and acts on the right rear wheel wheel brake BB via the inlet valve 5B. The brake hydraulic pressure output from the second output port 2 of the master cylinder M acts on the right front wheel wheel brake BC via the inlet valve 5C, and acts on the left rear wheel wheel brake BD via the inlet valve 5D. Works.

  The hydraulic pressure control valve means corresponding to the wheel that is about to enter the locked state among the hydraulic pressure control valve means VA to VD when the wheel is about to enter the locked state during the brake is the control unit C. Thus, the master cylinder M and the wheel brakes BA to BD are shut off and the wheel brakes BA to BD and the reservoirs 8A and 8B are connected to each other. That is, among the inlet valves 5A to 5D, the inlet valve corresponding to the wheel that is about to enter the locked state is closed by energization, and the outlet valve corresponding to the wheel among the outlet valves 6A to 6D. The valve is opened by energization. Thereby, a part of the brake fluid pressure of the wheel that is about to enter the locked state is absorbed by the first reservoir 8A or the second reservoir 8B, and the brake fluid pressure of the wheel that is about to enter the locked state is reduced. It will be.

  Further, when the brake fluid pressure is kept constant, each of the fluid pressure control valve means VA to VD causes the control unit C to shut off the wheel brakes BA to BD from the reservoirs 8A and 8B, and to fluid pressure from the master cylinder M. It is controlled so as to limit the action. That is, the outlet valves 6A to 6D are closed by de-energization, and the inlet valves 5A to 5D are energized and controlled so as to linearly change the hydraulic pressure downstream of the inlet valves 5A to 5D by controlling the applied current. Will be. Further, when the brake fluid pressure is increased, the outlet valves 6A to 6D are closed by de-energization, and the inlet valves 5A to 5D are controlled by controlling the current applied to the inlet valves 5A to 5D. The hydraulic pressure downstream of the inlet valves 5A to 5D is linearly controlled according to the applied current.

  Incidentally, the first and second pumps 10A and 10B are controlled by the control unit C so as to operate during the anti-lock brake control, and the brake fluid in the first and second reservoirs 8A and 8B is the first and second pumps. The second pumps 10A and 10B are recirculated to the master cylinder M side. Such recirculation of the brake fluid can prevent an increase in the amount of depression of the brake pedal P due to the absorption of the brake fluid into the first and second reservoirs 8A and 8B. Moreover, since the pulsations of the discharge pressures of the first and second pumps 10A and 10B are absorbed by the first and second dampers 12A and 12B, the operation feeling of the brake pedal P is not hindered by the reflux.

  In this way, at the time of anti-lock brake control, the outlet valves 6A to 6D are controlled to be turned on and off by the control unit C and switched between full open and fully closed, whereas the inlet valves 5A to 5D are fully opened and fully closed. Duty control in the closed and half-open states is possible, and it is controlled by on / off control and an intermediate value current between on and off, and each wheel brake according to such an intermediate value applied current. The configuration of the inlet valve 5A among the inlet valves 5A to 5D configured to linearly change the hydraulic pressure on the BA to BD side will be described below with reference to FIG.

  In FIG. 2, the inlet valve 5 </ b> A includes a solenoid portion 14 that exhibits electromagnetic force and a valve portion 15 that is driven by the solenoid portion 14, and opens to one surface 16 a of a fixed support block 16. Thus, the valve portion 15 is accommodated in the mounting hole 17 provided in the support block 16, and the solenoid portion 14 protrudes from the one surface 16 a of the support block 16.

  The valve portion 15 includes a valve housing 18 formed of a magnetic metal into a stepped cylindrical shape. The valve housing 18 is fitted into the mounting hole 17 of the support block 16. A retaining ring 19 that engages with the valve housing 18 and prevents the valve housing 18 from being detached from the mounting hole 17 is fitted to the inner surface of the mounting hole 17 near the opening end. In addition, annular seal members 20 and 21 are mounted at two positions on the outer surface of the valve housing 18 that are spaced apart in the axial direction, and between the seal members 20 and 21 between the support block 16 and the valve housing 18. An annular chamber 22 is formed.

  A cylindrical valve seat member 23 is press-fitted and fixed to the valve housing 18. A valve shaft 24 made of a non-magnetic material is slidably fitted in the valve housing 18, and an output chamber 25 is formed between one end of the valve shaft 24 and the valve seat member 23, and faces the output chamber 25. Thus, a spherical valve body 26 that can be seated on the valve seat 23 a formed on the valve seat member 23 is fixed to one end of the valve shaft 24. In addition, a return spring 27 is provided between one end of the valve shaft 24 and the valve seat member 23 to urge the valve shaft 24, that is, the valve body 26 in a direction away from the valve seat member 23.

  A filter 29 is attached to the valve housing 18 so as to be interposed between the hydraulic pressure path 28 provided in the support block 16 and connected to the first output hydraulic pressure path 3 and the valve seat member 23. A filter 30 is mounted on the outer periphery of the valve housing 18 at a portion facing the annular chamber 22, and a passage 31 for allowing the output chamber 25 to communicate with the annular chamber 22 through the filter 30 is provided in the valve housing 18. . The annular chamber 22 communicates with the left front wheel wheel brake BA, and the support block 16 is provided with a hydraulic path 32 for communicating the annular chamber 22 with the left front wheel wheel brake BA. Further, the valve housing 18 is opened between the valve seat member 23 and the filter 29 when the pressure in the hydraulic pressure passage 28 is lower than that in the annular chamber 22, and the brake fluid in the annular chamber 22 is returned to the hydraulic pressure passage 28 side. A check valve 7A is provided.

  The solenoid unit 14 guides the movement of the armature 36 toward and away from the fixed core 35, the armature 36 that is coaxially connected to the other end of the valve shaft 24 in the valve unit 15 and faces the fixed core 35. Guide cylinder 37, a bobbin 38 surrounding the guide cylinder 37, a coil 39 wound around the bobbin 38, a magnetic path frame 40 surrounding the coil 39, and the magnetic path frame 40 and the bobbin 38. The coiled spring 41 is provided.

  The fixed core 35 is formed in a cylindrical shape, and is coaxially and integrally connected to the central portion of one end of the valve housing 18. The guide cylinder 37 is formed in a thin bottomed cylindrical shape with a hemispherical closed end at one end made of a nonmagnetic material such as stainless steel, and the distal end of the fixed core 35 is connected to the other end of the guide cylinder 37. And the other end of the guide tube 37 is fixed to the fixed core 35 by welding, for example. In addition, the guide cylinder 37 protrudes from the one surface 16 a of the support block 16 in the mounting state of the valve housing 18 in the mounting hole 17.

  The bobbin 38 has a center hole 38a through which the guide cylinder 37 is inserted and is formed of synthetic resin. A coil 39 is wound around the bobbin 38.

  The magnetic path frame 40 includes a magnetic path cylinder 42 that surrounds the bobbin 38 and the coil 39. A ring plate-like magnetic path plate 43 that abuts on the bobbin 38 is caulked and engaged with one end of the magnetic path tube 42 so that the closed end of the guide tube 37 protrudes from the center.

  On the other hand, the other end of the magnetic path cylinder 42 is integrally provided with a ring plate-like contact plate portion 42a that contacts the one end of the valve housing 18 around the fixed core 35, and this contact plate portion 42a. The base portion of the fixed core 35 is fitted to the inner periphery of the fixed core 35. The other end of the coiled spring 41 having one end abutted against the abutting plate portion 42 a is abutted against the bobbin 38.

  An armature 36 that can move toward and away from the fixed core 35 is housed in the guide cylinder 37, and one end of the valve shaft 24 that movably penetrates the fixed core 35 is coaxial with the armature 36. Abutted. By the way, the valve shaft 24 is biased in a direction away from the valve seat member 23 by the spring force of the return spring 27, and the other end of the valve shaft 24 is always in contact with the armature 36. In response to the axial movement of the armature 36, the valve shaft 24, that is, the valve body 26 also moves in the axial direction.

  That is, in a state where the magnetic attractive force toward the fixed core 35 is not acting on the armature 36, the armature 36 is in a retracted position by the spring force of the return spring 27 until it is received at one end closed portion of the guide cylinder 37. At this time, the valve body 26 is separated from the valve seat member 23, and the inlet valve 5A is in a valve open state. Further, when the armature 36 is magnetically attracted to the fixed core 35 until the valve body 26 is seated on the valve seat member 23, the inlet valve 5A is closed.

  By the way, a combined force of the hydraulic pressure and the spring force of the return spring 27 acts on one end of the valve shaft 24 due to the hydraulic pressure of the output chamber 25, while an armature 36 is fixed to the other end of the valve shaft 24. The magnetic attraction force attracted to the core 35 side acts, and the valve shaft 24 is stroke-operated so that the resultant force of the fluid pressure and the spring force is balanced with the magnetic attraction force. Therefore, the magnetic attraction force for attracting the armature 36 toward the fixed core 35 can be changed by controlling the energization amount to the coil 39 by the control unit C so as to be an intermediate value between on and off.

  On the other hand, the opposed surfaces 35 a and 36 a of the fixed core 35 and the armature 36 are formed as tapered surfaces that increase in diameter as they move away from the output chamber 25.

  When the opposing surfaces 35a and 36a of the fixed core 35 and the armature 36 are formed in a tapered surface in this way, the opposing distance between the fixed core 35 and the armature 36 (in a direction perpendicular to the tapered surface) compared to the axial stroke amount of the armature 36. The change in the suction force generated between the opposed surfaces 35a and 36a is smaller than the change in the axial stroke. Moreover, the suction force that actually acts in the axial direction is the Sin component of the suction force generated between the opposing surfaces 35a and 36a, and with respect to the change in the suction force between the opposing surfaces 35a and 36a as the taper surface angle becomes acute. The change in the suction force in the axial direction is reduced.

  As a result, as shown by the solid line in FIG. 3, the suction force between the fixed core 35 and the armature 36 can be substantially flat in the practical range between the fully closed and fully opened states in the valve portion 15. On the other hand, when the opposing surfaces of the fixed core 35 and the armature 36 are flat surfaces perpendicular to the axial direction, the opposing distance between the fixed core 35 and the armature 36 changes in proportion to the axial stroke of the valve shaft 24. Therefore, as shown by the chain line in FIG. 3, the suction force between the fixed core 35 and the armature 36 changes greatly even in the practical range.

  In this way, the inlet valve 5A can be controlled to change the hydraulic pressure on the left front wheel brake BA side linearly by changing the duty between the fully closed state with a duty of 100% and the fully open state with a duty of 0%. The other inlet valves 5B to 5D are configured similarly to the normally open control valve 5A. On the other hand, the outlet valves 6A to 6D are only controlled to be turned on / off.

  In FIG. 4, in order to drive the inlet valves 5A to 5D, one end of the coil 39 is connected to the DC power source 45, and an energization control element for controlling energization from the power source 45 between the other end of the coil 39 and the ground. Field Effect Transistor (hereinafter referred to as FET) 46 is interposed. A free-wheeling diode 47 is connected in parallel to the coil 39, a diode 48 and a Zener diode 49 are connected in series between the drain and gate of the FET 46, and the gate of the FET 46 is grounded via a Zener diode 50. The

  The control unit C is connected to the gate of the FET 46, and performs on / off control of the inlet valves 5A to 5D and performs linear control in a half-open state by an intermediate current between on and off. The energization / cutoff of the FET 46 is controlled.

  By the way, the control unit C performs the depressurization, holding and pressure-increasing modes at the time of anti-lock brake control for controlling the brake fluid pressure of the wheel brake corresponding to the wheel that is about to enter the locked state among the wheel brakes BA to BD. The operation of the inlet valves 5A to 5D and the outlet valves 6A to 6D is controlled by repeating in this order, and the command signal for opening and closing the inlet valves 5A to 5D changes as shown in FIG. When the duty is held, a constant current lower than that in the on state is made to flow through the coil 39, and when the duty is increased, the current is repeatedly increased and decreased to apply a lower current to the coil 39 than in the on state. At the time of holding the duty and increasing the duty, the control unit C switches the energization / cutoff of the FET 46 by pulse width modulation. Controlled by the issue.

  In addition, according to the present invention, at the time of increasing the duty, the control unit C increases the energization amount to the coil 39 after the predetermined time T has elapsed since the start of the pressure increasing mode. FIG. 5 shows an example in which the duty of the command signal is increased after the predetermined time T has elapsed, but the frequency of the pulse signal by pulse width modulation is increased. Thus, the FET 46 may be controlled to increase the energization amount to the coil 39.

  Next, the operation of this embodiment will be described. In the duty pressure increasing mode at the time of anti-lock brake control, the control unit C has passed the predetermined time T from the start of the pressure increasing mode. Since the FET 46 is controlled to increase the energization amount to the coil 39 than before, it is possible to avoid a decrease in the energization current due to an increase in the resistance value due to the heat generation of the coil 39. As a result, the opening degree of the inlet valves 5A to 5D can be prevented from changing to a larger side, the pressure increasing speed can be prevented from being increased, and the occurrence of pressure pulsation can be prevented.

  Although the embodiments of the present invention have been described above, the present invention is not limited to the above-described embodiments, and various design changes can be made without departing from the present invention described in the claims. It is.

It is a brake fluid pressure circuit diagram of a brake device of a passenger vehicle. It is a longitudinal cross-sectional view of an inlet valve. It is a figure which shows the suction force change with respect to the stroke change of a valve shaft. It is a figure which shows the structure of the drive device of an inlet valve. It is a figure which shows an example of the command signal to the inlet valve at the time of antilock brake control.

Explanation of symbols

5A, 5B, 5C, 5D ... Inlet valve 39 ... Coil 45 ... DC power supply 46 ... Field effect transistors BA, BB, BC, BD ... Wheel brake C ..Control unit M ... Master cylinder P as hydraulic pressure generating means ... Brake pedal as brake operating member

Claims (1)

  It is configured as a normally-open linear solenoid valve that enables duty control in a half-open state between fully open and fully closed in accordance with the amount of energization to the coil (39) and the brake operating member (P) The hydraulic pressure generating means (M) for outputting hydraulic pressure according to the operation, the inlet valve (5A, 5B, 5C, 5D) interposed between the wheel brakes (BA, BB, BC, BD) and the coil ( 39) In the energization control element (46) for controlling energization from the DC power source (45) to the 39), and in the pressure increasing mode at the time of antilock brake control, the inlet valve (5A to 5D) is duty-controlled in a half-open state. An anti-lock brake control device for a vehicle comprising a control unit (C) for controlling the energization control element (46) as possible, wherein the control unit (C) 5A to 5D), when the duty control is performed in the half-open state, the energization amount to the coil (39) is larger than the predetermined time after the predetermined time has elapsed since the start of the pressure increasing mode. An antilock brake control device for a vehicle, which controls the energization control element (46).

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