JP3945132B2 - Brake system - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
  The present invention relates to a brake system including a brake booster used for a brake of an automobile or the like.
[0002]
[Prior art]
  Conventionally, as a brake system, pneumatic brakeBoosterThe brake system provided is well known.
  And barometricThe brake booster includes a valve body slidably provided in the shell, a power piston provided in the valve body, a constant pressure chamber and a variable pressure chamber formed before and after the power piston, and a flow path provided in the valve body. A valve mechanism that controls switching, and an input shaft that operates in conjunction with the brake pedal and advances the valve plunger that constitutes the valve mechanism to switch the flow path. The valve mechanism is applied to the brake pedal. The flow path is switched by being energized by the pedaling force, and an output corresponding to the magnitude of the pedaling force is generated.
[0003]
[Problems to be solved by the invention]
  The above brake system obtains the output of the brake booster according to the magnitude of the pedal effort of the brake pedal, but freely controls the output of the brake booster regardless of the input of the brake booster during brake operation. It may be required to do.
  For example, there is a case of a vehicle brake system equipped with a regenerative brake device as a case where it is required to reduce the output of the brake booster device regardless of the input of the brake booster device during braking. Since this regenerative braking device generates a braking force when it is activated, even if the pedal force of the brake pedal is kept constant, the overall braking force will fluctuate if the braking force by the regenerative braking device fluctuates. Will come to give.
  Therefore, in this case, if the braking force by the brake booster can be reduced by the amount that the regenerative braking device is activated and the braking force is increased, the entire braking force can be kept constant. No discomfort to the person. This occurs even when the engine brake or the exhaust brake is operated.
  On the other hand, as a case where it is required to increase the output of the brake booster regardless of the input of the brake booster during brake operation, there is a case of a brake system including a brake assist device. This brake assist device is designed to obtain an output larger than the output obtained by the pedaling force at the time of normal braking during sudden braking, so that even a weak woman or elderly person can perform sudden braking.
  Moreover, as a case where it is requested | required to increase the output of another brake booster, the case where it drive | works a downhill and the vehicle-mounted weight increases are mentioned.
  As described above, it has been conventionally required to freely control the output of the brake booster in various cases. However, conventionally, the brake booster is configured exclusively for each device and has no versatility. In order to meet this demand, many parts such as a solenoid valve and a pump are required, so that not only the configuration is complicated but also the cost is high.
  In view of such circumstances, the present invention enables the output of the brake booster to be freely controlled regardless of the depression force of the brake pedal in response to the increase or decrease of various brake forces as described above. A brake system is provided.
[0004]
[Means for Solving the Problems]
  That is, the invention of claim 1 is directed to a valve mechanism of a pneumatic brake booster that is energized by a pedaling force applied to a brake pedal to switch a flow path and generates an output corresponding to the magnitude of the pedaling force, and the valve mechanism. A solenoid that urges the pedal in the same direction or in the opposite direction to the pedaling force,
  The brake booster includes a valve body slidably provided in the shell, a power piston provided in the valve body, a constant pressure chamber and a variable pressure chamber formed before and after the power piston, and a flow path provided in the valve body. The valve mechanism for switching control, and an input shaft that interlocks with the brake pedal and switches the flow path by advancing the valve plunger that constitutes the valve mechanism,
  Further, the solenoid urges the solenoid plunger. The solenoid plunger is slidably disposed between the reaction disk of the brake booster and the valve plunger so as to brake the reaction force from the reaction disk. Is transmitted to the valve plunger, and the urging force is transmitted to the valve plunger,
  The solenoid increases or decreases an urging force applied to the valve plunger in response to a brake force increase request signal or a decrease request signal, thereby increasing or decreasing the output of the brake booster. Is.
  According to a fourth aspect of the present invention, there is provided a valve mechanism of a pneumatic brake booster that is energized by a pedaling force applied to a brake pedal to switch a flow path and generates an output corresponding to the magnitude of the pedaling force, and the valve mechanism A solenoid that urges the pedal in the same direction or in the opposite direction to the pedaling force,
  The brake booster includes a valve body slidably provided in the shell, a power piston provided in the valve body, a constant pressure chamber and a variable pressure chamber formed before and after the power piston, and a flow path provided in the valve body. The valve mechanism for switching control, and an input shaft that interlocks with the brake pedal and switches the flow path by advancing the valve plunger that constitutes the valve mechanism,
  The valve plunger includes an input shaft side member connected to the input shaft, and a valve side member provided slidably with respect to the input shaft side member and having a valve seat of the valve mechanism formed thereon. The valve side member is formed in a cylindrical shape and is provided on the outer periphery of the input shaft side member so as to be slidable while being sealed with a seal member, and a stopper portion extending radially inward is formed on the rear side portion. The valve seat is formed on the rear end surface of the stopper portion, and the valve side member is urged to the front side with respect to the input shaft side member, and the forward end is normally in contact with the input shaft side member. Held in position,
  Further, the solenoid urges a solenoid plunger, and the solenoid plunger is adapted to displace the valve side member from the forward end position to the rear side, and the solenoid receives a brake force increase request signal or a decrease request. The urging force applied to the valve mechanism is increased or decreased according to a signal to increase or decrease the output of the brake booster.Is.
[0005]
  the aboveClaims 1 and 4In any of the inventions, during normal braking operation, the valve mechanism is urged by the pedaling force applied to the brake pedal to switch the flow path and generate an output corresponding to the magnitude of the pedaling force. For example, when there is a brake force increase request signal, the solenoid increases the urging force applied to the valve mechanism in response to the signal, so that the output of the brake booster can be increased.
  As described above, since the urging force applied to the valve mechanism by the solenoid can be increased or decreased, the output of the brake booster can be freely controlled even when the pedaling force of the brake is constant.
[0006]
DETAILED DESCRIPTION OF THE INVENTION
  Hereinafter, the present invention will be described with reference to the illustrated embodiment. FIG. 1 shows an embodiment in which the present invention is applied to a brake system using a pneumatic brake booster VBB.Is.
  Above-mentioned pneumatic brake boosterVBB isAs is well known in the art, a valve mechanism is provided that is energized by a pedaling force applied to the brake pedal BP to switch the flow path and generates an output corresponding to the magnitude of the pedaling force.
  Above brake boosterIn VBBA master cylinder MCY is provided, and when the piston of the master cylinder MCY is moved forward by the brake booster, the brake fluid pressure generated thereby is supplied to the wheel cylinder W / C to perform the braking action. ing.
  Each brake boosterVBB hasAs detailed laterAnd aboveA solenoid SOL that urges the valve mechanism in the same direction or in the opposite direction to the pedaling force is provided, and the urging force of the solenoid SOL is controlled by the control unit ECU. The control device ECUFIG.As shown in FIG. 2, when there is a brake force increase request signal or a decrease request signal (S1), the energization current value to the solenoid SOL is determined according to the magnitude of the request signal (S2), and the determination is made. By actuating the solenoid based on the current value, the urging force is increased or decreased (S3), and the output of the brake booster is increased or decreased.
[0007]
  The brake force increase request signal and the decrease request signal can be obtained from various devices.
  For example, as a device for generating a brake force reduction request signal, there is a regenerative brake device. That is, in the brake system provided with the regenerative brake device, the brake force is generated in a state where the regenerative brake device is operated. Therefore, even if the depression force of the brake pedal BP is kept constant, the brake force by the regenerative brake device is maintained. When the vehicle speed fluctuates, the overall braking force fluctuates, and the driver feels uncomfortable.
  In such a case, a signal indicating the operating state of the regenerative brake device, that is, a brake force reduction request signal is input from the regenerative brake device to the control device ECU.
  In the control device ECU, the relationship between the magnitude of the brake force reduction request signal and the energization current value to the solenoid SOL corresponding to the magnitude is determined in advance by a table or an arithmetic expression. At this time, the relationship between the current value applied to the solenoid SOL and the braking force reduced thereby is also measured in advance.
  Therefore, when the brake force reduction request signal is input from the regenerative brake device, the control unit ECU calculates the magnitude of the brake force decrease request signal calculated from the magnitude or based on the input value from the regenerative brake device. Then, an energization current value to the solenoid SOL is determined, and the solenoid SOL is operated based on the determined current value.
  When the solenoid SOL is actuated in this manner, the urging force of the valve mechanism is reduced according to the energization current value and the output of the brake booster is reduced. Therefore, the braking force by the brake booster can be reduced by the amount of increase, and therefore the entire braking force can be kept constant even if the braking force caused by this changes based on the operation of the regenerative braking device. It does not give the driver a sense of incongruity.
  As another device for generating a brake force reduction request signal, there is a device for generating a brake force by operating an engine brake or an exhaust brake.
[0008]
  On the other hand, as a device that generates a brake force increase request signal, there is a brake assist device that increases the brake force according to the brake pedal force during sudden braking. More specifically, the brake assist device detects the depression speed of the brake pedal BP, the rising speed of the brake fluid pressure, and the like, and determines that the brake is suddenly braked when those values exceed a predetermined value. Then, the brake force increase request signal is input to the control unit ECU.
  In the control device ECU, the relationship between the magnitude of the brake force increase request signal and the energization current value to the solenoid SOL corresponding to the magnitude is determined in advance by a table or an arithmetic expression. At this time, the relationship between the energization current value to the solenoid SOL and the braking force increased thereby is also measured in advance.
  Therefore, when the brake force increase request signal is input from the brake assist device, the control device ECU increases the brake force obtained from the magnitude or the difference between the input value from the brake assist device and the predetermined value. An energization current value to the solenoid SOL is determined from the magnitude of the request signal, and the solenoid SOL is operated based on the determined current value.
  When the solenoid SOL is actuated, the urging force of the valve mechanism is increased in accordance with the energizing current value, and the output of the brake booster is increased, thereby increasing the braking force during sudden braking. Even a woman or an elderly person can perform a sudden braking operation. Further, as described above, the increase amount of the brake force depends on the brake pedal force, so that the increase amount of the brake force can be controlled by the driver's intention.
  Other devices that generate a braking force increase request signal include a device that detects downhill slopes and increases the braking force according to the amount of the gradient, or detects the vehicle weight and increases the vehicle load. There are devices that increase the braking force accordingly.
[0009]
  Next, a regenerative brake device RB (which uses the pneumatic brake booster VBB shown in FIG. 1 and generates a brake force reduction request signal)FIG.3, the front chamber 4 and the rear chamber 5 are partitioned in the front and rear by the center plate 3 in the shell 2 of the tandem brake booster VBB. A cylindrical valve body 6 is slidably passed through the rear side of the shell 2 and the center plate 3 while being hermetically sealed by seal means 7 and 8, respectively.
  A front power piston 10 and a rear power piston 11 are connected to the outer periphery of the valve body 6 located in the front chamber 4 and the rear chamber 5, respectively, and a front diaphragm 12 is connected to the back of each power piston 10, 11. And the rear diaphragm 13 are stretched. A constant pressure chamber A and a variable pressure chamber B are formed before and after the front diaphragm 12 in the front chamber 4, and a constant pressure chamber C and a variable pressure chamber D are formed before and after the rear diaphragm 13 in the rear chamber 5. .
  In the valve body 6, a valve mechanism 15 for switching the communication state between the constant pressure chambers A and C and the variable pressure chambers B and D is provided.
[0010]
  FIG.The valve mechanism 15 is slidable within the valve body 6 and a first valve seat 16 formed at the tip of a large-diameter annular protrusion extending from the inner periphery of the valve body 6 to the rear side. A valve plunger 18 that is fitted and interlocked with the input shaft 17 is provided, and a second valve seat 19 is formed at a rear end portion of the valve plunger 18. The valve body 21 is urged to the front side by the poppet return spring 20 and includes a first seat portion S1 seated on the first valve seat 16 and a second seat portion S2 seated on the second valve seat 19. .
  The valve body 21 includes a rolling part 24 whose rear side end is fixed airtight to the valve body 6 by a substantially cylindrical retainer 23, and a backup connected to the front side end of the rolling part 24. A plate 25 and a cylindrical portion 26 connected to the backup plate 25 and extending to the front side are provided, and a first seat made of an elastic body seated on the first valve seat 16 at the tip of the cylindrical portion 26. While providing the part S1, a second seat part S2 made of an elastic body seated on the second valve seat 19 is provided on the front side end face of the backup plate 25.
  Further, a valve return spring 27 is mounted between the retainer 23 and the input shaft 24, and the input shaft 17, the valve plunger 18 connected to the input shaft 17, and the valve plunger 18 by the elastic force of the valve return spring 27. The valve body 21 seated on the second valve seat 19 is biased to the rear side.
  Further, the valve plunger 18 is prevented from being pulled out from the valve body 6 by a conventionally known key member 28, and abuts against the seal member 7 attached to the shell 2 when the booster is not operated. By doing so, the valve plunger 18 is held in the advanced position with respect to the valve body 6.
[0011]
  Further, the valve mechanism 15 has an axial direction formed in a valve body 6 that communicates a space outside the vacuum valve 30 constituted by the first valve seat 16 and the first seat portion S1 to the constant pressure chamber A. A constant pressure passage 31 and a radial constant pressure passage 32 that communicates the constant pressure passage 31 and the constant pressure chamber C are provided. The engine is connected to the engine through a negative pressure introduction pipe (not shown) provided in the shell 2 with the constant pressure chamber A. By communicating with the intake manifold, negative pressure is always introduced into the constant pressure chambers A and C.
In addition, the space between the atmospheric valve 33 constituted by the second valve seat 19 and the second seat portion S2 and the vacuum valve 30 is communicated with the variable pressure chamber B via the radial variable pressure passage 34. The constant pressure chamber B communicates with another variable pressure chamber D through an axial variable pressure passage 35.
  The space on the inner side of the atmospheric valve 33 communicates with the atmosphere via the atmospheric passage 36, and a filter 37 is provided in the atmospheric passage 36.
[0012]
  On the front side of the valve plunger 18, a solenoid 41 and a solenoid plunger 42 for urging the valve plunger 18 to the rear side are provided. The solenoid 41 is formed in a ring shape, and a small-diameter cylindrical member 43 is attached to the right end portion thereof. The large-diameter cylindrical member 44 is mounted in the valve body 6 in a state where the solenoid 41 and the small-diameter cylindrical member 43 are accommodated in the stepped large-diameter cylindrical member 44.
  The solenoid plunger 42 includes a cylindrical member 46 and contact members 47 and 48 that are press-fitted and fixed to both ends of the cylindrical member 46. The cylindrical member 46 is connected to the front of the small-diameter cylindrical member 43. The rear side contact member 47 is slidably fitted into the small-diameter cylindrical member 43. Then, the tip end portion of the valve plunger 18 is slidably fitted into the small diameter cylindrical member 43 so that the tip end portion of the valve plunger 18 and the rear side end portion of the contact member 47 can come into contact with each other. It is. At this time, the rear side end surface of the contact member 47 is formed into a spherical surface, and an elastic member 49 such as rubber is attached to the rear side end surface of the cylindrical member 46, so that the cylindrical member 46 becomes the small diameter cylindrical member 43. The hitting sound at the time of collision can be prevented.
[0013]
  Further, a cylindrical holder 51 is attached to the front side of the stepped large diameter cylindrical member 44, and a plate plunger 52 is slidably provided in a central small diameter hole 51a of the cylindrical holder 51. Then, the left end portion of the cylindrical member 46 constituting the solenoid plunger 42 and the contact member 48 are slidably fitted into the medium diameter hole 51b provided continuously to the rear side of the small diameter hole 51a, thereby making contact. The member 48 and the plate plunger 52 can be brought into contact with each other.
  At this time, like the contact member 47, the front end surface of the contact member 48 is formed into a spherical surface, thereby making it difficult to transmit the inclination of the valve plunger 18 and the plate plunger 52 to the solenoid plunger 42. The stick of the plunger 42 can be prevented.
  A large-diameter hole 51c is connected to the front side of the small-diameter hole 51a, and the reaction disk 53 and the base of the output shaft 54 are fitted in the large-diameter hole 51c. The distal end portion of the output shaft 54 protrudes outside from the shaft portion of the shell 2 and is interlocked with a piston of a master cylinder (not shown).
  A return spring 56 is elastically mounted across the inner wall on the front side of the shell 2 and the retainer 55 in contact with the valve body 6 so that the valve body 6 is normally held at the non-operating position in the figure. The retainer 55 prevents the base portion of the output shaft 54 and the reaction disk 53 from falling out of the large-diameter hole 51c.
[0014]
  A wiring 61 drawn from the solenoid 41 is drawn to the front side of the valve body 6 through the constant pressure passage 31 and further connected to a connection terminal 62 provided on the retainer 55. The connection terminal 62 and a connection terminal 63 provided on the front end face of the shell 2 are connected by a flexible wiring 64, and the connection terminal 63 is connected to the above-described control unit ECU.
  The control device ECU is configured to input a signal from the regenerative brake device RB, and the control device ECU calculates a magnitude of a regenerative brake force by the regenerative brake device RB, that is, a brake force reduction request signal from the signal, In addition, by controlling the energization current to the solenoid 41 by PWM or the like based on the calculation result, the solenoid plunger 42 is urged to the rear side by the urging force corresponding to the regenerative braking force.
  The regenerative brake device RB performs a regenerative brake operation at the time of braking using a drive motor that drives the wheels of the electric vehicle, and since it has already been publicly known, a description of its specific configuration is omitted.
[0015]
  In the above configuration, the control device ECU excites the solenoid 41 only when a brake pedal (not shown) is depressed and the regenerative brake device RB is operated. In this case, the regenerative operation is performed as described above. The energization amount of the solenoid 41 corresponding to the braking force is calculated, and the solenoid plunger 42 is biased with the biasing force corresponding to the regenerative braking force.
  In other words, the solenoid 41 is not excited when the regenerative braking device RB is not operated, such as when parking or when the battery is fully charged, and if the brake pedal is depressed in this state, the valve mechanism 15 turns the solenoid 41 off. The flow path is switched in the same manner as a conventional general brake booster that is not provided. The characteristic diagram of the brake booster VBB at this timeFIG.Is shown by the diagram A in FIG.
  On the other hand, when the solenoid 41 is excited, the solenoid plunger 42 is urged to the rear side and the valve plunger 18 is urged to the rear side.FIG.As shown in the diagram B, the output of the brake booster decreases by the amount of the urging force, that is, the amount of the regenerative braking force. At this time, if the regenerative braking force is large, the urging force for urging the valve plunger 18 to the rear side also becomes large.FIG.If the regenerative braking force is small, the urging force for urging the valve plunger 18 to the rear side is also small.FIG.Move to the left side of
[0016]
  When the brake pedal is depressed, the brake booster VBB is activated to generate an output corresponding to the depression force, thereby obtaining a braking force. When the regenerative brake device RB is operated from this state and a regenerative brake force is generated, the control device ECU detects the operation of the regenerative brake device RB and excites the solenoid 41. At this time, the control device ECU urges the solenoid plunger 42 to the rear side with an urging force corresponding to the regenerative braking force via the solenoid 41. Therefore, when the regenerative braking force increases, the control device ECU moves to the rear side of the solenoid plunger 42 accordingly. As a result, the output of the brake booster VBB decreases.
  During this time, the output of the brake booster decreases, whereby the brake reaction force transmitted from the piston of the master cylinder to the brake pedal via the output shaft 54, the reaction disc 53, the solenoid plunger 42, the valve plunger 18 and the input shaft 17. However, since the urging force corresponding to the amount of the decrease is applied from the solenoid plunger 42 to the valve plunger 18, the depression force of the brake pedal is kept constant, and the driver does not feel uncomfortable.
  Further, if the regenerative braking force becomes constant, the output of the brake booster is also maintained constant, and if the regenerative braking force decreases, the output of the brake booster increases accordingly. If the regenerative braking force becomes zero, that is, if the operation of the regenerative braking device RB is stopped, the control device ECU deenergizes the solenoid 41.
[0017]
  FIG.Of the present inventionSecond embodimentIn the present embodiment, the second valve seat 19 is provided directly at the rear side end of the valve plunger 18, whereas in this embodiment, the valve plunger 118 is connected to the input shaft side member 118A and the valve. The side member 118B is composed of two members, the input shaft side member 118A is connected to the input shaft 117, and the valve side member 118B is provided with a second valve seat 119 that constitutes the atmospheric valve 133.
  That is, the valve side member 118B is formed in a cylindrical shape, and a stopper portion 171 extending radially inward is formed on the rear side portion thereof, and the second valve seat 119 is formed on the rear side end surface of the stopper portion 171. Is forming. The valve side member 118B is provided on the outer periphery of the input shaft side member 118A so as to be slidable while being sealed by a seal member 172. A spring 173 is elastically disposed between the valve side member 118B and the input shaft side member 118A. The valve-side member 118B is urged to the front side with respect to the input shaft-side member 118A, and the forward end is normally brought into contact with the rear-side end surface of the input shaft-side member 118A. They are held in position and connected together. At this time, the outer diameter d of the seal member 172 and the effective diameter d of the rolling part 124 of the valve body 121 are set to be substantially the same diameter, thereby making it difficult for differential pressure to be generated in the atmospheric valve 133.
  The key member 128 is adapted to engage with the input shaft side member 118A through a notch formed in the tubular valve side member 118B. The input shaft side member 118 </ b> A slidably passes through the solenoid plunger 142, and its tip directly contacts the plate plunger 152, and is interlocked with the reaction disk 153 via the plate plunger 152. . Further, a poppet return spring 120 that biases the valve body 121 to the front side is mounted between the backup plate 125 and the retainer 123.
  Other configurations are the same as those of the first embodiment, and the main portions of the corresponding portions are indicated by the same reference numerals as those of the first embodiment plus 100.
[0018]
  In the above configuration, the solenoid 141 is not excited in a state where the regenerative braking device is not operated also in the present embodiment. In this state, the input shaft side member 118 </ b> A and the valve side member 118 </ b> B constituting the valve plunger 118 are separated by the spring 173.FIG.While being held in this state, it operates integrally, and the operation at this time is the same as that of a conventional general brake booster.
  When the regenerative braking device is activated and the regenerative braking force is generated from the state where the brake pedal is depressed, the control device detects the operation of the regenerative braking device and excites the solenoid 141 in the same manner as in the first embodiment. The solenoid plunger 142 is urged rearward with an urging force corresponding to the regenerative braking force. ThenFIG.As shown in FIG. 4, the valve side member 118B is displaced rearward against the spring 173 and the poppet return spring 120, leaving the input shaft side member 118A, so that the valve body 121 is separated from the first valve seat 116. Sit down and the vacuum valve 130 is opened, which reduces the output of the brake booster.
  At this time, the urging force of the solenoid plunger 142 by the solenoid 141 strikes the urging force of the poppet return spring 120 and the urging force of the spring 173 elastically mounted between the valve side member 118B and the input shaft side member 118A. The valve-side member 118B only needs to be displaced to the rear side, and it is not necessary to overcome the pedal effort of the brake pedal and retract the valve plunger 18 as in the first embodiment, so that the output of the solenoid 141 can be reduced. Therefore, power consumption can be reduced. At this time, the front-side end surface of the stopper portion 171 is separated from the rear-side end surface of the input shaft-side member 118A.
[0019]
  When the vacuum valve 130 is opened, the pressure in the variable pressure chamber escapes to the constant pressure chamber, so that the difference between the atmospheric pressure acting on the valve body 121 and the pressure in the variable pressure chamber increases. As a result, the urging force to the front side of the valve body 121 increases, and when the output of the brake booster decreases by the urging force of the solenoid plunger 142, that is, the regenerative braking force, the valve body 121 is moved to the first valve seat. 116 is closed and the vacuum valve 130 is closed (FIG.). In this state, the front end surface of the stopper 171 remains separated from the rear end surface of the input shaft side member 118A.
  Further, at this time, the output of the brake booster is reduced, thereby reducing the brake reaction force transmitted from the output shaft to the brake pedal via the reaction disk 153, the plate plunger 152, the input shaft side member 118A and the input shaft 117. However, since the urging force corresponding to the reduced amount is applied from the solenoid plunger 142 to the input shaft side member 118A via the spring 173, the depression force of the brake pedal is kept constant and the driver does not feel uncomfortable. Absent.
  When the regenerative braking force becomes constant, the output of the brake booster is also maintained constant, and when the regenerative braking force decreases, the output of the brake booster increases accordingly. If the regenerative braking force becomes zero, that is, if the operation of the regenerative braking device is stopped, the control device turns off the solenoid 141.Extinguish.
[0020]
【The invention's effect】
  As described above, according to the present invention, it is possible to freely control the output of the brake booster regardless of the depression force of the brake pedal in response to a request for increase or decrease of the brake force. The effect is that it can be applied to a wide range of vehicle brake systems equipped with a brake, an exhaust brake device, a brake assist device, or the like.
[Brief description of the drawings]
FIG. 1 is a schematic configuration diagram showing a first embodiment of the present invention.
[Figure 2]In FIG.The flowchart of control apparatus ECU shown.
FIG. 3 is a sectional view showing a specific configuration of the first embodiment shown in FIG. 1;
[Fig. 4]FIG.The expanded sectional view of the principal part.
FIG. 5 is a characteristic diagram of the present invention.
FIG. 6 of the present inventionSecond embodimentThe expanded sectional view of the principal part which shows.
[Fig. 7]FIG.Sectional drawing which shows the operation state different from FIG.
[Fig. 8]6 and 7Sectional drawing which shows the operation state different from FIG.
[Explanation of symbols]
6, 106 ... Valve body 10, 11 ... Power piston
15,115 ...Valve mechanism 17,117 ...Input shaft
42, 142 ... Solenoid plunger 18, 118 ... Valve plunger
52, 152 ... Plate plunger 47, 48 ... Contact member
53, 153 ... Reaction disc 207 ... Spring
VBB... Pneumatic brake booster BP ... Brakepedal
ECU... Control device SOL ... Solenoid

Claims (6)

A valve mechanism of a pneumatic brake booster that is energized by a pedaling force applied to the brake pedal to switch a flow path and generates an output corresponding to the magnitude of the pedaling force, and the valve mechanism in the same direction as or reverse to the pedaling force. A solenoid that biases in the direction,
The brake booster includes a valve body slidably provided in the shell, a power piston provided in the valve body, a constant pressure chamber and a variable pressure chamber formed before and after the power piston, and a flow path provided in the valve body. The valve mechanism for switching control, and an input shaft that interlocks with the brake pedal and switches the flow path by advancing the valve plunger that constitutes the valve mechanism,
Furthermore, the solenoid urges the solenoid plunger, and this solenoid plunger is slidably disposed between the reaction disk of the brake booster and the valve plunger so as to brake the reaction force from the reaction disk. Is transmitted to the valve plunger, and the urging force is transmitted to the valve plunger,
The solenoid increases or decreases an urging force applied to the valve plunger in response to a brake force increase request signal or a decrease request signal, thereby increasing or decreasing the output of the brake booster. Brake system.   A plate plunger is slidably provided between the reaction disc and the solenoid plunger, and at least one of the contact surfaces of the plate plunger and the solenoid plunger and at least one of the contact surfaces of the solenoid plunger and the valve plunger. The brake system according to claim 1, wherein one of the two is a spherical surface.   The solenoid plunger is provided with a contact member that contacts the plate plunger at one end and a contact member that contacts the valve plunger at the other end, and the spherical surface is formed on each contact member. The brake system according to claim 2. A valve mechanism of a pneumatic brake booster that is energized by a pedaling force applied to the brake pedal to switch a flow path and generates an output corresponding to the magnitude of the pedaling force, and the valve mechanism in the same direction as or reverse to the pedaling force. A solenoid that biases in the direction,
The brake booster includes a valve body slidably provided in the shell, a power piston provided in the valve body, a constant pressure chamber and a variable pressure chamber formed before and after the power piston, and a flow path provided in the valve body. The valve mechanism for switching control, and an input shaft that interlocks with the brake pedal and switches the flow path by advancing the valve plunger that constitutes the valve mechanism,
The valve plunger includes an input shaft side member connected to the input shaft, and a valve side member provided slidably with respect to the input shaft side member and having a valve seat of the valve mechanism formed thereon. The valve side member is formed in a cylindrical shape and is provided on the outer periphery of the input shaft side member so as to be slidable while being sealed with a seal member, and a stopper portion extending radially inward is formed on the rear side portion. The valve seat is formed on the rear end surface of the stopper portion, and the valve side member is urged to the front side with respect to the input shaft side member, and the forward end is normally in contact with the input shaft side member. Held in position,
Further, the solenoid urges a solenoid plunger, and the solenoid plunger is adapted to displace the valve side member from the forward end position to the rear side, and the solenoid receives a brake force increase request signal or a decrease request. A brake system characterized by increasing or decreasing an urging force applied to the valve mechanism in response to a signal to increase or decrease the output of the brake booster.   The brake system according to claim 4, wherein the input shaft member is slidably penetrated through the solenoid plunger and interlocked with a reaction disk of a brake booster. The energizing force of the solenoid is controlled by a control device, and the control device calculates an energization current value to the solenoid according to the magnitude of the brake force increase request signal or the decrease request signal, and this current brake system according to any one of claims 1 to claim 5, characterized in that to control the biasing force of the solenoid based on the value.

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