JP2012153367A - Pedal simulator - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a brake device with which the position of a brake pedal can adjusted reliably even while a power actuator disposed in the brake pedal is reduced in size and in capacity.SOLUTION: A cylinder mechanism 11 includes a housing 70, a piston 72 slidably held in the housing 70 to form a liquid chamber 73 to which operating fluids are guided, and a plurality of dish springs 90 and 92 for pressing the piston 72 to the liquid chamber 73 side. The bottom surfaces of at least two of the plurality of disk springs 90 and 92 are arranged to face each other, and a ring 94 is disposed to abut, in a circular-arc shape, on the inner slopes 90a and 92a of the disk springs 90 and 92.

Description

  The present invention relates to a cylinder mechanism configured to urge a piston forming a liquid chamber into which hydraulic fluid is guided by a plurality of disc springs toward the liquid chamber.

  2. Description of the Related Art In recent years, a motor cylinder or a hydraulic pump for applying hydraulic pressure to a braking force generator provided on a wheel based on operation information such as a pedaling force of a brake pedal (hereinafter also simply referred to as a pedal) input to an ECU of a vehicle Brake devices have been proposed that electrically control the drive.

  In this type of electronic control of brakes using electrical signals, the so-called brake-by-wire system, braking that is more faithful to pedal operation than the hydraulic control system in which a pedal and a master cylinder are directly connected has been widely used. And smooth braking can be realized.

  In a brake device that employs brake-by-wire, a pedal simulator (stroke simulator) is provided to obtain a reaction force against the depression of the pedal, whereby a predetermined amount of pedal depression (stroke, operation amount) and pedaling force are provided. A characteristic (stroke-pedal force characteristic) is given.

  In Patent Document 1, as a pedal simulator as described above, a cylinder mechanism including a piston that forms (defines) a fluid chamber into which hydraulic fluid is guided and a plurality of disc springs that bias the piston toward the fluid chamber. Is disclosed. In this case, due to the characteristics of the disc spring, the stroke and pedaling force characteristics are non-linear, that is, the pedal operating torque (stepping rigidity) is reduced at the beginning of stepping on the pedal, and the operating torque (stepping rigidity) is increased as the pedal is depressed. Therefore, it is possible to give the driver a feeling of pedal operation without a sense of incongruity.

Japanese Patent Laid-Open No. 6-211124

  In the cylinder mechanism constituting the pedal simulator described in Patent Document 1, most of the disc springs are stacked in the same direction. For this reason, in order to make the sliding distance of the piston sufficient, it is necessary to arrange a considerable number of disc springs, which increases the cost.

  Therefore, in order to reduce the number of disc springs used in such a cylinder mechanism, a method is conceivable in which the bottom surfaces of the disc springs are arranged facing each other in the housing 100 as shown in FIG. 9A. That is, the disc spring 102 is arranged so that its conical shape is upward, and the disc spring 104 is arranged so that its conical shape is downward (reverse). As a result, the number of stacked disc springs can be reduced, and a sufficient sliding distance of the piston 106 can be obtained.

  However, a slight clearance C is usually required between the disc springs 102 and 104 and the housing 100 and the shaft body 108 in consideration of the deflection of the disc springs 102 and 104 (see FIG. 9A). Accordingly, as shown in FIG. 9B, when the piston 106 is pushed in and the disc springs 102 and 104 are contracted and then extended again as shown in FIG. 9C, each disc spring 102, 104 may cause a deviation in the diameter direction. That is, there is a possibility that a deviation A due to the clearance C occurs at various locations between the disc springs 102 and 104 (see FIG. 9C).

  In the portion where the deviation A occurs, irregular sliding resistance is generated between the disc springs every time when the disc springs contract and extend, so that the characteristics of the pedal stroke and the pedal force change in a complicated manner every time the disc springs contract. Thus, it becomes difficult to obtain a stable stroke-treading force characteristic. In other words, when the disc springs are simply arranged facing each other, it is difficult to maintain (maintain) the overlapping state of the disc springs at a constant level. It causes individual differences in each mechanism.

  The present invention has been made in order to solve the above-described conventional problems, and even when the bias of the piston forming the liquid chamber through which the working fluid is guided is performed by a disc spring, the number of use of the disc spring is reduced. It is an object of the present invention to provide a cylinder mechanism that can be effectively reduced and can obtain a stable spring characteristic.

  A cylinder mechanism according to the present invention includes a housing, a piston that is slidably held in the housing and forms a liquid chamber through which hydraulic fluid is guided, and a plurality of disc springs that urge the piston toward the liquid chamber. And a bottom surface of at least two disc springs among the plurality of disc springs is arranged to face each other, and an arc with respect to the inner surface of the disc springs arranged to face each other It is characterized in that a circular member that abuts is provided.

  Further, the cylinder mechanism according to the present invention includes a housing, a piston that is slidably held in the housing and forms a liquid chamber through which hydraulic fluid is guided, and a plurality of pistons that urge the piston toward the liquid chamber. A cylinder mechanism comprising a disc spring, wherein the bottom surfaces of at least two disc springs among the plurality of disc springs are arranged so as to face each other, and the bottom surfaces of the disc springs are arranged in the axial direction of the disc springs. A movement blocking means for blocking movement in the orthogonal direction is provided.

  According to such a structure, one disc spring is compared with the case where each disc spring is laminated | stacked in the same direction by arrange | positioning the bottom face of at least two disc springs mutually facing among the plurality of disc springs. It is possible to prevent the upper surface side from being buried in the bottom surface side of another disc spring and to obtain a sufficient stroke while reducing the number of disc springs used. Furthermore, since the movement (displacement) in the direction perpendicular to the axial direction of the disc springs arranged so that the bottom faces face each other can be prevented by the circular member or the movement preventing means, for example, the expansion and contraction of each disc spring It is possible to effectively prevent the characteristic from changing each time, and to obtain a stable desired spring characteristic. In particular, in the case of the circular member, the inner surfaces of the disc springs, the bottom surfaces of which face each other, are in contact with the circular arc on the outer peripheral side of the circular member. It becomes possible to arrange. For this reason, it becomes possible to hold | maintain each disc spring mutually with respect to the diameter direction orthogonal to an axial direction, and can prevent the movement (shift | offset | difference) to this diameter direction effectively.

  Furthermore, when the circular member is movable in the axial direction and is arranged in a state in which movement is restricted in a direction orthogonal to the axial direction, the circular member itself moves (displaces) in the diametrical direction. Therefore, when a plurality of disc springs having the bottom surfaces facing each other are used, it is preferable because displacement between each set can be effectively prevented.

  According to the present invention, the bottom surfaces of at least two disc springs among the plurality of disc springs that urge the piston forming the liquid chamber through which the working fluid is guided to the liquid chamber side are arranged to face each other. As a result, the upper surface side of one disc spring is prevented from being buried in the bottom surface side of the other disc spring, and a sufficient stroke can be obtained while reducing the number of disc springs used. In addition, since the movement of the disc springs arranged so that the bottoms face each other in the direction perpendicular to the axial direction is blocked by the circular member and the movement blocking means, the characteristics change each time the disc springs expand and contract. This can be effectively prevented, and stable desired spring characteristics can be obtained.

It is a block circuit diagram of a brake device carrying a pedal simulator to which a cylinder mechanism according to an embodiment of the present invention is applied. It is a schematic sectional drawing in alignment with the axial direction of the cylinder mechanism which concerns on one Embodiment of this invention. 3A is a cross-sectional view schematically showing the structure of the first spring member of the cylinder mechanism shown in FIG. 2, and FIG. 3B is a cross-sectional view showing a state in which the first spring member shown in FIG. 3A is contracted. . FIG. 3 is a partially omitted cross-sectional perspective view of a first spring member of the cylinder mechanism shown in FIG. 2. FIG. 3B is a cross-sectional view schematically showing a state in which the first spring member shown in FIG. 3A is displaced between sets of disc springs. 6A is a cross-sectional view schematically showing a first spring member according to a modification of the first spring member shown in FIG. 3A, and FIG. 6B schematically shows a state in which the first spring member shown in FIG. 6A is contracted. FIG. FIG. 7A is a schematic cross-sectional view showing a state in which the piston is retracted due to hydraulic pressure and a liquid chamber is formed in the cylinder mechanism shown in FIG. 2, and FIG. 7B is a further piston retracted from the state shown in FIG. 7A. It is a schematic sectional drawing which shows the state moved. It is a graph which shows the relationship between the pedal effort and stroke. FIG. 9A is a cross-sectional view schematically showing a state in which the bottom surfaces of the disc springs are arranged facing each other without providing a ring, and FIG. 9B is a state in which the disc springs are contracted from the state shown in FIG. 9A. FIG. 9C is a cross-sectional view schematically showing a state in which the disc spring is extended again from the state shown in FIG. 9B.

  DESCRIPTION OF EMBODIMENTS Hereinafter, a cylinder mechanism according to the present invention will be described in detail with reference to the accompanying drawings by giving preferred embodiments in relation to a brake device equipped with a pedal simulator as an application example of the cylinder mechanism.

  First, a brake device for a vehicle equipped with a pedal simulator to which a cylinder mechanism according to the present invention is applied will be described. FIG. 1 is a block circuit diagram of a brake device 10 equipped with pedal simulators 13L and 13R to which a cylinder mechanism 11 according to an embodiment of the present invention is applied.

  The brake device 10 is mounted on a vehicle such as an automobile, and based on the operation of a pedal (brake pedal) 12 by a driver (operator), a braking force generator (caliper, wheel cylinder, Brake cylinder) is a device that brakes the vehicle by holding the disks 15L and 15R with 14L and 14R to generate a braking force. In FIG. 1, only the left wheel LW and the right wheel RW constituting the front wheel side of the automobile are shown, and the rear wheel side is not shown, but the front wheel side (left wheel LW) is also shown on the rear wheel side. And the right wheel RW) and other configurations can be provided. Further, in the brake device 10, reference numerals for components provided on the left wheel LW side are denoted by “L”, reference numerals for components provided on the right wheel RW side are denoted by “R”, and the left wheel LW side and When collectively explaining the right wheel RW side, the above-mentioned “L” and “R” are omitted.

  The brake device 10 generates a braking force by a pedal 12 that is operated by a driver according to a driving condition, a master cylinder 16 that is driven in conjunction with the operation of the pedal 12, and the braking force generators 14L and 14R. Motor cylinders (hydraulic pressure generating units, caliper cylinders) 18L and 18R for applying a hydraulic pressure for the purpose. Each component of the brake device 10 is electrically connected to and controlled by the ECU 20 that is a control unit.

  That is, the brake device 10 includes a hydraulic pressure (hydraulic pressure) system that connects hydraulic pressure (hydraulic pressure) between the components and an electric system that electrically connects the components and the ECU 20. The In FIG. 1, a path (flow path) constituting the hydraulic system is indicated by a solid line, and a path (signal line) constituting the electrical system is indicated by a broken line. Examples of the liquid filled in the hydraulic system include brake fluid.

  As shown in FIG. 1, the pedal 12 includes a pedal operation information detection unit 22 that detects a force by which the driver depresses the pedal 12 (stepping force) and an amount (operation amount, stroke) of the pedal 12 operated by the driver. The detected value of the pedal operation information detection unit 22 is input to the ECU 20. For example, a torque sensor provided on the tread surface of the pedal 12 is used to detect the pedaling force, and a potentiometer (rotary potentiometer) is used to detect the stroke. Note that the pedal operation information detection unit 22 may be configured to detect only the pedal effort.

  An electric actuator (actuator, reaction force motor) 24 is connected to the vicinity of the swing shaft on the base end side of the pedal 12. The electric actuator 24 adjusts the reaction force against the depression of the driver's pedal 12 and the position of the pedal 12 under the control of the ECU 20. The electric actuator 24 can apply torque to the pedal 12, that is, the electric actuator 24 may also function as a pedal operation information detection unit 22 that detects the pedaling force of the pedal 12.

  The master cylinder 16 includes two pistons 26L and 26R arranged in order in the axial direction, a rod 28 whose rear end is connected to the pedal 12 to drive the pistons 26L and 26R forward and backward, and the inside of the cylinder 16a is the piston 26L, It is composed of two pressurizing chambers 30L and 30R that are partitioned by 26R. The pressurizing chambers 30L and 30R are provided with return springs (elastic members) 32L and 32R that return the pistons 26L and 26R that have been moved by the depression of the pedal 12 to their original positions.

  The pressurizing chambers 30L and 30R are connected to the braking force generators 14L and 14R by main paths 33L and 33R.

  The motor cylinders 18L, 18R can drive the pistons 38L, 38R forward and backward within the cylinders 40L, 40R by connecting the rear ends of the rods 34L, 34R to brake motors (caliper motors) 36L, 36R. The pressurizing chambers 42L, 42R constituting the motor cylinders 18L, 18R are connected to the main paths 33L, 33R via the paths 44L, 44R. That is, the pressurizing chamber 42 of the motor cylinder 18 is connected to the braking force generator 14.

  In the main paths 33L and 33R, the pedal simulator (PS) to which the cylinder mechanism 11 according to the present embodiment is applied via the paths 46L and 46R closer to the master cylinder 16 than the paths 44L and 44R. 13L and 13R are connected.

  Further, passages 54 </ b> L and 54 </ b> R connected to the reserve tank 52 communicate with the pressurizing chambers 30 </ b> L and 30 </ b> R of the master cylinder 16. The reserve tank 52 functions to adjust the hydraulic pressure (fluid amount) of the hydraulic system of the brake device 10. Furthermore, auxiliary paths 56L and 56R communicating with the pressurizing chambers 42L and 42R of the motor cylinders 18L and 18R are connected to the reserve tank 52. The paths 54L and 54R and the auxiliary paths 56L and 56R join together before being connected to the reserve tank 52.

  In the path 54 connected to the reserve tank 52, the opening communicating with the pressurizing chamber 30 is formed close to the original position of the piston 26. As a result, when the pistons 26L and 26R advance from their original positions (if they move slightly), the opening is closed, that is, the paths 54L and 54R are blocked between the pressurizing chambers 30L and 30R and the reserve tank 52. Is done. The auxiliary route 56 is configured in substantially the same manner as the route 54 described above. That is, the auxiliary paths 56L and 56R are blocked between the pressurizing chambers 42L and 42R and the reserve tank 52 at the same time as the pistons 38L and 38R advance from their original positions.

  In such a brake device 10, master cylinder pressure sensors 58L, 58R, fail-safe valves 60L, 60R, brake pressure sensors (caliper pressure sensors) are provided in the main paths 33L, 33R in order from the pressurizing chambers 30L, 30R side. ) 62L and 62R are disposed. Brake valves (caliper valves) 64L and 64R are disposed in the paths 44L and 44R. Simulator valves (PS valves) 66L and 66R are disposed in the paths 46L and 46R.

  The fail-safe valve 60 is provided between the main path 33 and the connecting part of the path 44 and the connecting part of the path 46. When the solenoid 60a is excited under the control of the ECU 20, the fail-safe valve 60 communicates with the main path 33. Cut off. Similarly, under the control of the ECU 20, the brake valve 64 communicates or blocks the path 44 when the solenoid 64a is excited, and the simulator valve 66 communicates or blocks the path 46 when the solenoid 66a is excited.

  In FIG. 1, for the sake of simplicity, the signal lines connected from the master cylinder pressure sensor 58 and the brake pressure sensor 62 to the ECU 20 and the signal lines connected from the solenoids 60a, 64a, 66a to the ECU 20 are omitted. Yes.

  In the brake device 10 configured as described above, the operation information of the pedal 12 is normally detected by the pedal operation information detection unit 22 and input to the ECU 20 at the normal time. Then, the motor cylinder 18 is driven based on a command from the ECU 20, the braking force is generated by the braking force generator 14, and a braking operation is performed. That is, the brake device 10 is configured as a system (brake-by-wire) that employs the by-wire technology.

  Therefore, at the normal time when the brake device 10 is driven and controlled as brake-by-wire (when the system is turned on), first, the brake valve 64 and the simulator valve 66 are opened under the control of the ECU 20, and the fail-safe valve 60 is closed. To do.

  When the driver operates the pedal 12 in this state, the hydraulic pressure generated in the pressurizing chamber 30 of the master cylinder 16 by the operation of the pedal 12 is given to the pedal simulator 13 (cylinder mechanism 11). Reaction force can be obtained.

  At the same time, operation information (stepping force and stroke) of the pedal 12 is input to the ECU 20 from the pedal operation information detection unit 22, and the motor cylinder 18 is driven and controlled by the ECU 20 based on the operation information. As a result, the hydraulic pressure generated in the motor cylinder 18 is applied to the braking force generation unit 14, and the braking force generation unit 14 generates braking force to brake the left wheel LW and the right wheel RW.

  On the other hand, when the brake device 10 is not driven and controlled as a brake-by-wire (when the system is off), for example, when the system is stopped when the ignition is off, the fail-safe valve 60 is first opened under the control of the ECU 20. Then, the brake valve 64 and the simulator valve 66 are closed (see FIG. 1).

  When the driver operates the pedal 12 in this state, the hydraulic pressure generated in the pressurizing chamber 30 of the master cylinder 16 by the operation of the pedal 12 is applied to the braking force generation unit 14 and is controlled by the braking force generation unit 14. Power is generated and the left wheel LW and the right wheel RW are braked. At this time, the reaction force to the pedal 12 can be obtained by the master cylinder 16.

  Furthermore, in the brake device 10, the initial position of the pedal 12 can be changed. That is, when the initial position of the pedal 12 is changed, first, when the driver turns on the position change switch 68, the fail safe valve 60 and the brake valve 64 are opened and the simulator valve 66 is closed under the control of the ECU 20. .

  When the driver operates the position change switch 68 in this state, the electric actuator 24 is driven and the pedal 12 can be moved under the control of the ECU 20. Moreover, when such an initial position change of the pedal 12 is changed, the hydraulic pressure (fluid amount) of the movement of the piston 26 constituting the moved master cylinder 16 as the pedal 12 is moved by the electric actuator 24 is the main path. 33 is sent to the pressurizing chamber 42 of the motor cylinder 18 through the brake valve 64. As a result, the hydraulic pressure for the movement is returned to the reserve tank 52 via the auxiliary path 56.

  Thus, in the brake device 10, the reaction force at the pedal 12 when the system is on is given by the pedal simulator 13. That is, the pedaling force and stroke characteristics of the pedal 12 reflect the characteristics of the cylinder mechanism 11 constituting the pedal simulator 13. Therefore, the cylinder mechanism 11 has, for example, a stable characteristic that is substantially the same in the same vehicle model on which the brake device 10 is mounted and does not change with time, and a non-linear characteristic of stroke and pedal force, that is, the pedal 12 starts to be depressed. Therefore, it is important to reduce the operating torque (stepping rigidity) and increase the operating torque (stepping rigidity) as the pedal 12 is depressed, and to give the driver a feeling of comfortable pedal operation.

  Then, next, the cylinder mechanism 11 which concerns on this embodiment is demonstrated with reference to FIGS. FIG. 2 is a schematic cross-sectional view along the axial direction of the cylinder mechanism 11 according to the present embodiment.

  As shown in FIG. 2, the cylinder mechanism 11 includes a cylindrical housing 70 and a piston 72 slidably held in the housing 70. The opening 70a on one end side (arrow X1 side) of the housing 70 is closed by inserting a plug (lid member) 74 having a communication hole 74a formed in the axial direction (arrow X direction in FIG. 2). Yes. The communication hole 74a opens (communication) into a hole 74b having a diameter larger than that of the communication hole 74a in the direction of the arrow X2, and the piston 72 is axial (in the direction of arrow X in FIG. 2) in the hole 74b. It is slidably inserted in. In other words, the hole 74b functions as a cylinder for driving the piston 72 forward and backward, and hydraulic fluid (for example, brake fluid of the brake device 10) from the path 75 connected to the outer end surface of the plug 74 to the communication hole 74a. Is introduced, the hydraulic pressure of the hydraulic fluid is transmitted to the tip surface (operation surface) 72a of the piston 72. As a result, the piston 72 is retracted in the direction of the arrow X2 by the hydraulic pressure of the hydraulic fluid supplied from the communication hole 74a, or advanced in the direction of the arrow X1 by the urging force of the first and second spring members 82a and 84a described later. By being moved, a liquid chamber 73 into which hydraulic fluid is introduced is formed (defined) between the tip surface 72a and the plug 74 (see FIG. 7A).

  A slightly larger diameter recess 72b is opened on the surface of the piston 72 on the arrow X2 side, and a recess 72c having a smaller diameter than the recess 72b is opened on the bottom surface of the recess 72b.

  In the plug 74, the hole 74b that holds the piston 72 is formed as an inner peripheral surface of a cylindrical portion 74c that projects in the direction of the arrow X2. The outer peripheral surface of the cylindrical portion 74c is slidably held in a recess 76a of a transmission member 76 that partitions the inside of the housing 70 in the arrow X direction. The transmission member 76 has a bottomed cylindrical shape having the concave portion 76a that is recessed toward the arrow X2, and a flange portion 76b is provided from the edge of the concave portion 76a along the diameter direction.

  A disc-shaped support member 78 is seated on the bottom of the recess 76a constituting the transmission member 76, and a support shaft (support rod) 80 projects in the direction of the piston 72 (arrow X1 direction) at the center. It is installed. The support shaft 80 holds a first spring member 82a that urges the piston 72 toward the arrow X1 between the recess 72b of the piston 72.

  On the other hand, a second spring member 84a that urges the transmission member 76 to the arrow X1 side is disposed on the arrow X2 side of the flange portion 76b constituting the transmission member 76. The second spring member 84a is held at its axial end by a plug (lid member) 86 that closes the opening 70b on the other end side (arrow X2 side) of the housing 70 and the flange portion 76b. The diameter direction is held by the housing 70 and the transmission member 76. In the case of this embodiment, the second spring member 84a has a higher spring constant than the first spring member 82a. A buffer member (rubber member) 88 is fitted in the center of the plug 86 to suppress abnormal noise and breakage due to bottom butt against the plug 86 when the transmission member 76 is greatly displaced toward the arrow X2.

  Here, the structure of the 1st and 2nd spring members 82a and 84a which urge the piston 72 is demonstrated with reference to FIG. 3A, FIG. 3B, and FIG. 3A is a cross-sectional view schematically showing the structure of the first spring member 82a, and FIG. 3B is a cross-sectional view schematically showing a state in which the first spring member 82a shown in FIG. 3A is contracted. FIG. 4 is a partially omitted cross-sectional perspective view of the first spring member 82a. The first spring member 82a and the second spring member 84a have substantially the same basic structure except that their inner and outer diameters, spring constants, holding forms, and the like are different. Therefore, the first spring member 82a will be specifically described below. The description of the second spring member 84a will be omitted.

  As shown in FIGS. 3A and 4, the first spring member 82 a (second spring member 84 a) has a plurality of disc springs 90 and 92 each having a truncated cone shape having an open top surface and a bottom surface. The support shaft 80 (in the case of the second spring member 84a, the transmission member 76) is inserted with the upper surfaces facing each other. That is, one disc spring 90 is arranged so that its conical shape is upward, and the other disc spring 92 is arranged so that its conical shape is downward (opposite to the disc spring 90). A plurality of sets of disc springs 92 (three sets in the case of this embodiment) are stacked. Note that the disc spring 90 and the disc spring 92 have the same shape, spring constant, and the like except that the arrangement directions are different.

  Furthermore, a ring (circular member) 94 that is inserted through the support shaft 80 is provided on the inner surface side of the disc springs 90 and 92 that constitute each set in which the bottom surfaces face each other. The ring 94 has a donut shape, and arcs (curved surfaces) constituting the outer periphery thereof are in contact with the inner inclined surfaces (inner surfaces) 90 a and 92 a of the disc springs 90 and 92. The ring 94 only needs to be able to come into contact with the inner inclined surfaces 90a and 92a by an arc, and the cross-sectional shape thereof may be a square having a curvature at a corner other than a circle or an ellipse.

  Therefore, as shown in FIG. 3B, when the first spring member 82a is contracted by the pressing action of the piston 72, the disc springs 90 and 92 constituting each set have contact points with the arc on the outer peripheral side of the ring 94, respectively. It will bend in the axial direction as a fulcrum. At this time, the pair of disc springs 90 and 92 that constitute the set and are in contact with the ring 94 are in contact with the arc on the outer peripheral side of the ring 94, so that they are arranged concentrically with each other. And held together in the diametrical direction perpendicular to the axial direction. Thereby, in the 1st spring member 82a, the movement (shift | offset | difference) in the said diametrical direction between the disc springs 90 and 92 in each set is prevented, and the concentricity between the disc springs 90 and 92 is maintained. Even when the expansion and contraction is repeated, it is possible to effectively prevent the characteristic from changing every time the expansion and contraction occurs, and a stable desired spring characteristic can be obtained. In other words, the ring 94 functions as a means for preventing movement in the diameter direction perpendicular to the axial direction of the disc springs 90 and 92 in each set (movement prevention means, displacement prevention means).

  In the first spring member 82a (second spring member 84a) having such a ring 94, the movement (displacement) in the diametrical direction perpendicular to the axial direction between the disc springs 90 and 92 constituting each set is not. Although blocked by the ring 94, there may be some deviation between each set. That is, when the first spring member 82a or the second spring member 84a contracts, the rings 94 provided in each set slightly move in the diameter direction. As shown in FIG. 5, for example, a deviation A may occur at a contact portion between the disc spring 92 constituting one set and the disc spring 90 constituting another set in contact therewith.

  Therefore, in the cylinder mechanism 11 according to the present embodiment, as shown in FIGS. 6A and 6B, the ring 94 is replaced by a first spring member 82b or a second spring member 84b in place of a slightly flat ring (circular member) 96. It is also possible.

  The ring 96 constituting the first spring member 82 b (second spring member 84 b) has an inner hole 96 a through which the support shaft 80 (transmission member 76 in the case of the second spring member 84 a) is inserted than that of the ring 94. The diameter is also small. Thereby, the ring 96 is arranged inside the disc springs 90 and 92 in a state where movement (displacement) in the diametrical direction perpendicular to the axial direction is reliably regulated. Therefore, in the first spring member 82b (second spring member 84b), the ring 96 can surely prevent diametrical displacement between the sets, and a plurality of combinations of the disc springs 90 and 92 are stacked. In the case of use, it is particularly effective because stable desired spring characteristics can be obtained even if expansion and contraction are repeated.

  In the ring 96, the inner hole 96a has a minimum clearance with respect to the support shaft 80 (the transmission member 76 in the case of the second spring member 84a), that is, the support shaft 80 when the first spring member 82b contracts. It is necessary to have a slidable clearance with respect to. In this sense, the ring 96 is not required to substantially deviate in the diametrical direction, and the diametrical movement is performed by the clearance to such an extent that the spring characteristics of the first spring member 82b and the like are not greatly affected. It may be allowed.

  Basically, in the cylinder mechanism 11 configured as described above, when hydraulic fluid is supplied from the path 75 into the communication hole 74a and the hydraulic pressure of the hydraulic fluid is transmitted to the tip surface 72a of the piston 72, The piston 72 moves backward (slids) in the direction of the arrow X2 against the urging force of the first spring member 82a (first spring member 82b). Along with the retraction of the piston 72, a liquid chamber 73 into which hydraulic fluid is introduced is formed between the distal end surface 72a and the plug 74 (see FIG. 7A). The hydraulic fluid is, for example, the hydraulic pressure from the master cylinder 16 in the case of the brake device 10, and in this case, the path 75 corresponds to the path 46 (see FIG. 1).

  Subsequently, when the piston 72 is further retracted in the direction of the arrow X2 by the hydraulic pressure of the hydraulic fluid and the piston 72 comes into contact with the support member 78 (see FIG. 7A) (see FIG. 7A), this time, the second spring member 84a. The biasing force of the (second spring member 84b) acts, and the piston 72 moves backward (slids) in the direction of the arrow X2 against the biasing force of the second spring member 84a (see FIG. 7B).

  Therefore, according to the cylinder mechanism 11 according to this embodiment, in the first spring member 82a and the like, a plurality of disc springs 90 and 92 having non-linear characteristics even if they are single items are further laminated. As a result, when the disc springs 90 and 92 are bent, in addition to the repulsive force of the disc springs 90 and 92, the disc springs 90 and 92 slide with each other so that the disc springs 90 and 92 contract. Resistance will increase. Therefore, when the cylinder mechanism 11 is applied as the pedal simulator 13 as in the brake device 10, the pedal effort (reaction force) of the pedal 12 can be increased as the stroke of the pedal 12 increases (the line in FIG. 8). B1). Also, when the pedal 12 is returned, the sliding resistance between the disc springs 90 and 92 decreases as the disc springs 90 and 92 extend. Thereby, at the time of the return operation of the pedal 12, a hysteresis characteristic is added to the characteristics of the stroke and the pedaling force (see line B2 in FIG. 8). Thereby, according to the pedal simulator 13 to which the cylinder mechanism 11 is applied, the characteristics of the stroke and the treading force become the optimum non-linearity as shown in FIG. 8, and it is possible to give the driver a feeling of pedal operation without feeling uncomfortable.

  The cylinder mechanism 11 includes second spring members 84a and 84b having a larger spring constant than the first spring members 82a and 82b in addition to the first spring members 82a and 82b, and biases the piston 72 in two stages. Thus, the stroke and pedaling force characteristics of the pedal 12 can be further improved.

  In the cylinder mechanism 11, the bottom surfaces (upper surfaces) of the disc springs 90 and 92 constituting each set are arranged to face each other. For this reason, compared with the case where each disc spring is laminated in the same direction, the upper surface side of each disc spring is not buried in the bottom surface side, and a sufficient stroke can be obtained with a small number of sheets, thereby reducing the cost. be able to.

  The ring 96 is more preferable than the ring 94 because it can surely prevent the deviation in the diameter direction, but the number of sets including the disc springs 90 and 92, for example, one set is preferable. As a result, the ring 94 can also be used effectively when there is no deviation between sets, or depending on the use conditions of the cylinder mechanism 11 and the like.

  In the brake device 10 equipped with the pedal simulator 13 to which the cylinder mechanism 11 according to the present invention is applied, the reaction force generated in the pedal simulator 13 as the reaction force of the pedal 12 is detected by, for example, the pedal operation information detection unit 22. It can be corrected by the electric actuator 24 on the basis of the pedaling force that has been made, and even better characteristics can be obtained.

  Needless to say, the application example of the cylinder mechanism 11 according to the present invention is not limited to the pedal simulator 13, and the brake device 10 is not limited to that shown in FIG. 1.

  As described above, the present invention has been described with the embodiment. However, the present invention is not limited to this, and it is naturally possible to adopt various configurations without departing from the gist of the present invention.

DESCRIPTION OF SYMBOLS 10 ... Brake apparatus 11 ... Cylinder mechanism 12 ... Pedal 13L, 13R ... Pedal simulator 26L, 26R, 38L, 38R, 72 ... Piston 70 ... Housing 72a ... End surface 73 ... Liquid chamber 74, 86 ... Plug 74a ... Communication hole 76 ... Transmission member 78 ... support member 80 ... support shafts 82a and 82b ... first spring members 84a and 84b ... second spring members 90 and 92 ... disc springs 90a and 92a ... inner slopes 94 and 96 ... rings

The present invention relates to a pedal simulator that absorbs hydraulic pressure generated in a pressurizing chamber of a master cylinder by operation of a brake pedal by a cylinder mechanism .

  2. Description of the Related Art In recent years, a motor cylinder or a hydraulic pump for applying hydraulic pressure to a braking force generator provided on a wheel based on operation information such as a pedaling force of a brake pedal (hereinafter also simply referred to as a pedal) input to an ECU of a vehicle Brake devices have been proposed that electrically control the drive.

  In this type of electronic control of brakes using electrical signals, the so-called brake-by-wire system, braking that is more faithful to pedal operation than the hydraulic control system in which a pedal and a master cylinder are directly connected has been widely used. And smooth braking can be realized.

  In a brake device that employs brake-by-wire, a pedal simulator (stroke simulator) is provided to obtain a reaction force against the depression of the pedal, whereby a predetermined amount of pedal depression (stroke, operation amount) and pedaling force are provided. A characteristic (stroke-pedal force characteristic) is given.

  In Patent Document 1, as a pedal simulator as described above, a cylinder mechanism including a piston that forms (defines) a fluid chamber into which hydraulic fluid is guided and a plurality of disc springs that bias the piston toward the fluid chamber. Is disclosed. In this case, due to the characteristics of the disc spring, the stroke and pedaling force characteristics are non-linear, that is, the pedal operating torque (stepping rigidity) is reduced at the beginning of stepping on the pedal, and the operating torque (stepping rigidity) is increased as the pedal is depressed. Therefore, it is possible to give the driver a feeling of pedal operation without a sense of incongruity.

Japanese Patent Laid-Open No. 6-211124

The present invention has been made in connection with the pedal simulator described above, and it is an object of the present invention to provide a pedal simulator that can suppress abnormal noise and breakage due to a bottom butt to a cover member that covers an opening of a housing .

A pedal simulator according to the present invention is a pedal simulator that absorbs hydraulic pressure generated in a pressurizing chamber of a master cylinder by operation of a brake pedal by a cylinder mechanism, and the cylinder mechanism slides in the housing and the housing. A piston that forms a fluid chamber through which hydraulic fluid can be held, and a plurality of disc springs that urge the piston toward the fluid chamber , and the housing has the opposite direction to the piston. An opening of the housing and a cover member that covers the opening and is formed of a member different from the housing are provided, and a buffer member made of a rubber material is provided on the cover member .

In the pedal simulator, the buffer member may have a stepped portion whose width increases from the piston toward the opening when viewed in an axial cross section.

According to the present invention, in the pedal simulator, it is possible to suppress abnormal noise and breakage due to bottom butt on the lid member covering the opening of the housing .

It is a block circuit diagram of a brake system equipped with engagement Lupe dull simulator to an embodiment of the present invention. It is a schematic cross-sectional view along the axial direction of the cylinder mechanism shown in FIG. 3A is a cross-sectional view schematically showing the structure of the first spring member of the cylinder mechanism shown in FIG. 2, and FIG. 3B is a cross-sectional view showing a state in which the first spring member shown in FIG. 3A is contracted. . FIG. 3 is a partially omitted cross-sectional perspective view of a first spring member of the cylinder mechanism shown in FIG. 2. FIG. 3B is a cross-sectional view schematically showing a state in which the first spring member shown in FIG. 3A is displaced between sets of disc springs. 6A is a cross-sectional view schematically showing a first spring member according to a modification of the first spring member shown in FIG. 3A, and FIG. 6B schematically shows a state in which the first spring member shown in FIG. 6A is contracted. FIG. FIG. 7A is a schematic cross-sectional view showing a state in which the piston is retracted due to hydraulic pressure and a liquid chamber is formed in the cylinder mechanism shown in FIG. 2, and FIG. 7B is a further piston retracted from the state shown in FIG. 7A. It is a schematic sectional drawing which shows the state moved. It is a graph which shows the relationship between the pedal effort and stroke.

Hereinafter, the pedal simulator according to the present invention, DESCRIPTION OF THE PREFERRED EMBODIMENTS A preferred embodiment in relation to a brake device equipped with the pedal simulator will be described in detail with reference to the accompanying drawings.

It will be described first braking device for a vehicle equipped with engagement Lupe dull simulator present invention. Figure 1 is a block circuit diagram of the brake system 10 to be mounted to one embodiment engaging Lupe Dal simulator 13L, the 13R of the present invention.

  The brake device 10 is mounted on a vehicle such as an automobile, and based on the operation of a pedal (brake pedal) 12 by a driver (operator), a braking force generator (caliper, wheel cylinder, Brake cylinder) is a device that brakes the vehicle by holding the disks 15L and 15R with 14L and 14R to generate a braking force. In FIG. 1, only the left wheel LW and the right wheel RW constituting the front wheel side of the automobile are shown, and the rear wheel side is not shown, but the front wheel side (left wheel LW) is also shown on the rear wheel side. And the right wheel RW) and other configurations can be provided. Further, in the brake device 10, reference numerals for components provided on the left wheel LW side are denoted by “L”, reference numerals for components provided on the right wheel RW side are denoted by “R”, and the left wheel LW side and When collectively explaining the right wheel RW side, the above-mentioned “L” and “R” are omitted.

  The brake device 10 generates a braking force by a pedal 12 that is operated by a driver according to a driving condition, a master cylinder 16 that is driven in conjunction with the operation of the pedal 12, and the braking force generators 14L and 14R. Motor cylinders (hydraulic pressure generating units, caliper cylinders) 18L and 18R for applying a hydraulic pressure for the purpose. Each component of the brake device 10 is electrically connected to and controlled by the ECU 20 that is a control unit.

  That is, the brake device 10 includes a hydraulic pressure (hydraulic pressure) system that connects hydraulic pressure (hydraulic pressure) between the components and an electric system that electrically connects the components and the ECU 20. The In FIG. 1, a path (flow path) constituting the hydraulic system is indicated by a solid line, and a path (signal line) constituting the electrical system is indicated by a broken line. Examples of the liquid filled in the hydraulic system include brake fluid.

  As shown in FIG. 1, the pedal 12 includes a pedal operation information detection unit 22 that detects a force by which the driver depresses the pedal 12 (stepping force) and an amount (operation amount, stroke) of the pedal 12 operated by the driver. The detected value of the pedal operation information detection unit 22 is input to the ECU 20. For example, a torque sensor provided on the tread surface of the pedal 12 is used to detect the pedaling force, and a potentiometer (rotary potentiometer) is used to detect the stroke. Note that the pedal operation information detection unit 22 may be configured to detect only the pedal effort.

  An electric actuator (actuator, reaction force motor) 24 is connected to the vicinity of the swing shaft on the base end side of the pedal 12. The electric actuator 24 adjusts the reaction force against the depression of the driver's pedal 12 and the position of the pedal 12 under the control of the ECU 20. The electric actuator 24 can apply torque to the pedal 12, that is, the electric actuator 24 may also function as a pedal operation information detection unit 22 that detects the pedaling force of the pedal 12.

  The master cylinder 16 includes two pistons 26L and 26R arranged in order in the axial direction, a rod 28 whose rear end is connected to the pedal 12 to drive the pistons 26L and 26R forward and backward, and the inside of the cylinder 16a is the piston 26L, It is composed of two pressurizing chambers 30L and 30R that are partitioned by 26R. The pressurizing chambers 30L and 30R are provided with return springs (elastic members) 32L and 32R that return the pistons 26L and 26R that have been moved by the depression of the pedal 12 to their original positions.

  The pressurizing chambers 30L and 30R are connected to the braking force generators 14L and 14R by main paths 33L and 33R.

  The motor cylinders 18L, 18R can drive the pistons 38L, 38R forward and backward within the cylinders 40L, 40R by connecting the rear ends of the rods 34L, 34R to brake motors (caliper motors) 36L, 36R. The pressurizing chambers 42L, 42R constituting the motor cylinders 18L, 18R are connected to the main paths 33L, 33R via the paths 44L, 44R. That is, the pressurizing chamber 42 of the motor cylinder 18 is connected to the braking force generator 14.

Said main path 33L, the 33R, the path 44L, the master cylinder 16 side than 44R, path 46L, through the 46R, shea cylinder mechanism 11 has been applied the pedal simulator (P.S.) 13L, 13R is It is connected.

  Further, passages 54 </ b> L and 54 </ b> R connected to the reserve tank 52 communicate with the pressurizing chambers 30 </ b> L and 30 </ b> R of the master cylinder 16. The reserve tank 52 functions to adjust the hydraulic pressure (fluid amount) of the hydraulic system of the brake device 10. Furthermore, auxiliary paths 56L and 56R communicating with the pressurizing chambers 42L and 42R of the motor cylinders 18L and 18R are connected to the reserve tank 52. The paths 54L and 54R and the auxiliary paths 56L and 56R join together before being connected to the reserve tank 52.

  In the path 54 connected to the reserve tank 52, the opening communicating with the pressurizing chamber 30 is formed close to the original position of the piston 26. As a result, when the pistons 26L and 26R advance from their original positions (if they move slightly), the opening is closed, that is, the paths 54L and 54R are blocked between the pressurizing chambers 30L and 30R and the reserve tank 52. Is done. The auxiliary route 56 is configured in substantially the same manner as the route 54 described above. That is, the auxiliary paths 56L and 56R are blocked between the pressurizing chambers 42L and 42R and the reserve tank 52 at the same time as the pistons 38L and 38R advance from their original positions.

  In such a brake device 10, master cylinder pressure sensors 58L, 58R, fail-safe valves 60L, 60R, brake pressure sensors (caliper pressure sensors) are provided in the main paths 33L, 33R in order from the pressurizing chambers 30L, 30R side. ) 62L and 62R are disposed. Brake valves (caliper valves) 64L and 64R are disposed in the paths 44L and 44R. Simulator valves (PS valves) 66L and 66R are disposed in the paths 46L and 46R.

  The fail-safe valve 60 is provided between the main path 33 and the connecting part of the path 44 and the connecting part of the path 46. When the solenoid 60a is excited under the control of the ECU 20, the fail-safe valve 60 communicates with the main path 33. Cut off. Similarly, under the control of the ECU 20, the brake valve 64 communicates or blocks the path 44 when the solenoid 64a is excited, and the simulator valve 66 communicates or blocks the path 46 when the solenoid 66a is excited.

  In FIG. 1, for the sake of simplicity, the signal lines connected from the master cylinder pressure sensor 58 and the brake pressure sensor 62 to the ECU 20 and the signal lines connected from the solenoids 60a, 64a, 66a to the ECU 20 are omitted. Yes.

  In the brake device 10 configured as described above, the operation information of the pedal 12 is normally detected by the pedal operation information detection unit 22 and input to the ECU 20 at the normal time. Then, the motor cylinder 18 is driven based on a command from the ECU 20, the braking force is generated by the braking force generator 14, and a braking operation is performed. That is, the brake device 10 is configured as a system (brake-by-wire) that employs the by-wire technology.

  Therefore, at the normal time when the brake device 10 is driven and controlled as brake-by-wire (when the system is turned on), first, the brake valve 64 and the simulator valve 66 are opened under the control of the ECU 20, and the fail-safe valve 60 is closed. To do.

  When the driver operates the pedal 12 in this state, the hydraulic pressure generated in the pressurizing chamber 30 of the master cylinder 16 by the operation of the pedal 12 is given to the pedal simulator 13 (cylinder mechanism 11). Reaction force can be obtained.

  At the same time, operation information (stepping force and stroke) of the pedal 12 is input to the ECU 20 from the pedal operation information detection unit 22, and the motor cylinder 18 is driven and controlled by the ECU 20 based on the operation information. As a result, the hydraulic pressure generated in the motor cylinder 18 is applied to the braking force generation unit 14, and the braking force generation unit 14 generates braking force to brake the left wheel LW and the right wheel RW.

  On the other hand, when the brake device 10 is not driven and controlled as a brake-by-wire (when the system is off), for example, when the system is stopped when the ignition is off, the fail-safe valve 60 is first opened under the control of the ECU 20. Then, the brake valve 64 and the simulator valve 66 are closed (see FIG. 1).

  When the driver operates the pedal 12 in this state, the hydraulic pressure generated in the pressurizing chamber 30 of the master cylinder 16 by the operation of the pedal 12 is applied to the braking force generation unit 14 and is controlled by the braking force generation unit 14. Power is generated and the left wheel LW and the right wheel RW are braked. At this time, the reaction force to the pedal 12 can be obtained by the master cylinder 16.

  Furthermore, in the brake device 10, the initial position of the pedal 12 can be changed. That is, when the initial position of the pedal 12 is changed, first, when the driver turns on the position change switch 68, the fail safe valve 60 and the brake valve 64 are opened and the simulator valve 66 is closed under the control of the ECU 20. .

  When the driver operates the position change switch 68 in this state, the electric actuator 24 is driven and the pedal 12 can be moved under the control of the ECU 20. Moreover, when such an initial position change of the pedal 12 is changed, the hydraulic pressure (fluid amount) of the movement of the piston 26 constituting the moved master cylinder 16 as the pedal 12 is moved by the electric actuator 24 is the main path. 33 is sent to the pressurizing chamber 42 of the motor cylinder 18 through the brake valve 64. As a result, the hydraulic pressure for the movement is returned to the reserve tank 52 via the auxiliary path 56.

  Thus, in the brake device 10, the reaction force at the pedal 12 when the system is on is given by the pedal simulator 13. That is, the pedaling force and stroke characteristics of the pedal 12 reflect the characteristics of the cylinder mechanism 11 constituting the pedal simulator 13. Therefore, the cylinder mechanism 11 has, for example, a stable characteristic that is substantially the same in the same vehicle model on which the brake device 10 is mounted and does not change with time, and a non-linear characteristic of stroke and pedal force, that is, the pedal 12 starts to be depressed. Therefore, it is important to reduce the operating torque (stepping rigidity) and increase the operating torque (stepping rigidity) as the pedal 12 is depressed, and to give the driver a feeling of comfortable pedal operation.

Therefore, it will now be described with reference to FIGS. 2-8 for shea cylinder mechanism 11. Figure 2 is a schematic cross-sectional view along the axial direction of the sheet cylinder mechanism 11.

  As shown in FIG. 2, the cylinder mechanism 11 includes a cylindrical housing 70 and a piston 72 slidably held in the housing 70. The opening 70a on one end side (arrow X1 side) of the housing 70 is closed by inserting a plug (lid member) 74 having a communication hole 74a formed in the axial direction (arrow X direction in FIG. 2). Yes. The communication hole 74a opens (communication) into a hole 74b having a diameter larger than that of the communication hole 74a in the direction of the arrow X2, and the piston 72 is axial (in the direction of arrow X in FIG. 2) in the hole 74b. It is slidably inserted in. In other words, the hole 74b functions as a cylinder for driving the piston 72 forward and backward, and hydraulic fluid (for example, brake fluid of the brake device 10) from the path 75 connected to the outer end surface of the plug 74 to the communication hole 74a. Is introduced, the hydraulic pressure of the hydraulic fluid is transmitted to the tip surface (operation surface) 72a of the piston 72. As a result, the piston 72 is retracted in the direction of the arrow X2 by the hydraulic pressure of the hydraulic fluid supplied from the communication hole 74a, or advanced in the direction of the arrow X1 by the urging force of the first and second spring members 82a and 84a described later. By being moved, a liquid chamber 73 into which hydraulic fluid is introduced is formed (defined) between the tip surface 72a and the plug 74 (see FIG. 7A).

  A slightly larger diameter recess 72b is opened on the surface of the piston 72 on the arrow X2 side, and a recess 72c having a smaller diameter than the recess 72b is opened on the bottom surface of the recess 72b.

  In the plug 74, the hole 74b that holds the piston 72 is formed as an inner peripheral surface of a cylindrical portion 74c that projects in the direction of the arrow X2. The outer peripheral surface of the cylindrical portion 74c is slidably held in a recess 76a of a transmission member 76 that partitions the inside of the housing 70 in the arrow X direction. The transmission member 76 has a bottomed cylindrical shape having the concave portion 76a that is recessed toward the arrow X2, and a flange portion 76b is provided from the edge of the concave portion 76a along the diameter direction.

  A disc-shaped support member 78 is seated on the bottom of the recess 76a constituting the transmission member 76, and a support shaft (support rod) 80 projects in the direction of the piston 72 (arrow X1 direction) at the center. It is installed. The support shaft 80 holds a first spring member 82a that urges the piston 72 toward the arrow X1 between the recess 72b of the piston 72.

  On the other hand, a second spring member 84a that urges the transmission member 76 to the arrow X1 side is disposed on the arrow X2 side of the flange portion 76b constituting the transmission member 76. The second spring member 84a is held at its axial end by a plug (lid member) 86 that closes the opening 70b on the other end side (arrow X2 side) of the housing 70 and the flange portion 76b. The diameter direction is held by the housing 70 and the transmission member 76. In the case of this embodiment, the second spring member 84a has a higher spring constant than the first spring member 82a. A buffer member (rubber member) 88 is fitted in the center of the plug 86 to suppress abnormal noise and breakage due to bottom butt against the plug 86 when the transmission member 76 is greatly displaced toward the arrow X2.

  Here, the structure of the 1st and 2nd spring members 82a and 84a which urge the piston 72 is demonstrated with reference to FIG. 3A, FIG. 3B, and FIG. 3A is a cross-sectional view schematically showing the structure of the first spring member 82a, and FIG. 3B is a cross-sectional view schematically showing a state in which the first spring member 82a shown in FIG. 3A is contracted. FIG. 4 is a partially omitted cross-sectional perspective view of the first spring member 82a. The first spring member 82a and the second spring member 84a have substantially the same basic structure except that their inner and outer diameters, spring constants, holding forms, and the like are different. Therefore, the first spring member 82a will be specifically described below. The description of the second spring member 84a will be omitted.

  As shown in FIGS. 3A and 4, the first spring member 82 a (second spring member 84 a) has a plurality of disc springs 90 and 92 each having a truncated cone shape having an open top surface and a bottom surface. The support shaft 80 (in the case of the second spring member 84a, the transmission member 76) is inserted with the upper surfaces facing each other. That is, one disc spring 90 is arranged so that its conical shape is upward, and the other disc spring 92 is arranged so that its conical shape is downward (opposite to the disc spring 90). A plurality of sets of disc springs 92 (three sets in the case of this embodiment) are stacked. Note that the disc spring 90 and the disc spring 92 have the same shape, spring constant, and the like except that the arrangement directions are different.

  Furthermore, a ring (circular member) 94 that is inserted through the support shaft 80 is provided on the inner surface side of the disc springs 90 and 92 that constitute each set in which the bottom surfaces face each other. The ring 94 has a donut shape, and arcs (curved surfaces) constituting the outer periphery thereof are in contact with the inner inclined surfaces (inner surfaces) 90 a and 92 a of the disc springs 90 and 92. The ring 94 only needs to be able to come into contact with the inner inclined surfaces 90a and 92a by an arc, and the cross-sectional shape thereof may be a square having a curvature at a corner other than a circle or an ellipse.

  Therefore, as shown in FIG. 3B, when the first spring member 82a is contracted by the pressing action of the piston 72, the disc springs 90 and 92 constituting each set have contact points with the arc on the outer peripheral side of the ring 94, respectively. It will bend in the axial direction as a fulcrum. At this time, the pair of disc springs 90 and 92 that constitute the set and are in contact with the ring 94 are in contact with the arc on the outer peripheral side of the ring 94, so that they are arranged concentrically with each other. And held together in the diametrical direction perpendicular to the axial direction. Thereby, in the 1st spring member 82a, the movement (shift | offset | difference) in the said diametrical direction between the disc springs 90 and 92 in each set is prevented, and the concentricity between the disc springs 90 and 92 is maintained. Even when the expansion and contraction is repeated, it is possible to effectively prevent the characteristic from changing every time the expansion and contraction occurs, and a stable desired spring characteristic can be obtained. In other words, the ring 94 functions as a means for preventing movement in the diameter direction perpendicular to the axial direction of the disc springs 90 and 92 in each set (movement prevention means, displacement prevention means).

  In the first spring member 82a (second spring member 84a) having such a ring 94, the movement (displacement) in the diametrical direction perpendicular to the axial direction between the disc springs 90 and 92 constituting each set is not. Although blocked by the ring 94, there may be some deviation between each set. That is, when the first spring member 82a or the second spring member 84a contracts, the rings 94 provided in each set slightly move in the diameter direction. As shown in FIG. 5, for example, a deviation A may occur at a contact portion between the disc spring 92 constituting one set and the disc spring 90 constituting another set in contact therewith.

Therefore, the sheet cylinder mechanism 11, as shown in FIGS. 6A and 6B, it is also possible to first spring member 82b and the second spring member 84b for changing the ring 94 slightly flattened ring (circular member) 96 is there.

  The ring 96 constituting the first spring member 82 b (second spring member 84 b) has an inner hole 96 a through which the support shaft 80 (transmission member 76 in the case of the second spring member 84 a) is inserted than that of the ring 94. The diameter is also small. Thereby, the ring 96 is arranged inside the disc springs 90 and 92 in a state where movement (displacement) in the diametrical direction perpendicular to the axial direction is reliably regulated. Therefore, in the first spring member 82b (second spring member 84b), the ring 96 can surely prevent diametrical displacement between the sets, and a plurality of combinations of the disc springs 90 and 92 are stacked. In the case of use, it is particularly effective because stable desired spring characteristics can be obtained even if expansion and contraction are repeated.

  In the ring 96, the inner hole 96a has a minimum clearance with respect to the support shaft 80 (the transmission member 76 in the case of the second spring member 84a), that is, the support shaft 80 when the first spring member 82b contracts. It is necessary to have a slidable clearance with respect to. In this sense, the ring 96 is not required to substantially deviate in the diametrical direction, and the diametrical movement is performed by the clearance to such an extent that the spring characteristics of the first spring member 82b and the like are not greatly affected. It may be allowed.

  Basically, in the cylinder mechanism 11 configured as described above, when hydraulic fluid is supplied from the path 75 into the communication hole 74a and the hydraulic pressure of the hydraulic fluid is transmitted to the tip surface 72a of the piston 72, The piston 72 moves backward (slids) in the direction of the arrow X2 against the urging force of the first spring member 82a (first spring member 82b). Along with the retraction of the piston 72, a liquid chamber 73 into which hydraulic fluid is introduced is formed between the distal end surface 72a and the plug 74 (see FIG. 7A). The hydraulic fluid is, for example, the hydraulic pressure from the master cylinder 16 in the case of the brake device 10, and in this case, the path 75 corresponds to the path 46 (see FIG. 1).

  Subsequently, when the piston 72 is further retracted in the direction of the arrow X2 by the hydraulic pressure of the hydraulic fluid and the piston 72 comes into contact with the support member 78 (see FIG. 7A) (see FIG. 7A), this time, the second spring member 84a. The biasing force of the (second spring member 84b) acts, and the piston 72 moves backward (slids) in the direction of the arrow X2 against the biasing force of the second spring member 84a (see FIG. 7B).

Therefore, according to Shi cylinder mechanism 11, in such a first spring member 82a, the disc springs 90, 92 having a non-linear characteristic even separately, are further laminated plural. As a result, when the disc springs 90 and 92 are bent, in addition to the repulsive force of the disc springs 90 and 92, the disc springs 90 and 92 slide with each other so that the disc springs 90 and 92 contract. Resistance will increase. Therefore, when the cylinder mechanism 11 is applied as the pedal simulator 13 as in the brake device 10, the pedal effort (reaction force) of the pedal 12 can be increased as the stroke of the pedal 12 increases (the line in FIG. 8). B1). Also, when the pedal 12 is returned, the sliding resistance between the disc springs 90 and 92 decreases as the disc springs 90 and 92 extend. Thereby, at the time of the return operation of the pedal 12, a hysteresis characteristic is added to the characteristics of the stroke and the pedaling force (see line B2 in FIG. 8). Thereby, according to the pedal simulator 13 to which the cylinder mechanism 11 is applied, the characteristics of the stroke and the treading force become the optimum non-linearity as shown in FIG. 8, and it is possible to give the driver a feeling of pedal operation without feeling uncomfortable.

  The cylinder mechanism 11 includes second spring members 84a and 84b having a larger spring constant than the first spring members 82a and 82b in addition to the first spring members 82a and 82b, and biases the piston 72 in two stages. Thus, the stroke and pedaling force characteristics of the pedal 12 can be further improved.

  In the cylinder mechanism 11, the bottom surfaces (upper surfaces) of the disc springs 90 and 92 constituting each set are arranged to face each other. For this reason, compared with the case where each disc spring is laminated in the same direction, the upper surface side of each disc spring is not buried in the bottom surface side, and a sufficient stroke can be obtained with a small number of sheets, thereby reducing the cost. be able to.

  The ring 96 is more preferable than the ring 94 because it can surely prevent the deviation in the diameter direction, but the number of sets including the disc springs 90 and 92, for example, one set is preferable. As a result, the ring 94 can also be used effectively when there is no deviation between sets, or depending on the use conditions of the cylinder mechanism 11 and the like.

Also, pedal force in the braking device 10 equipped with the pedal simulator 13 to which the sheet cylinder mechanism 11, a reaction force generated by the pedal simulator 13 as a reaction force of the pedal 12, for example, detected by the pedal operation information detecting unit 22 Based on the above, it can be corrected by the electric actuator 24 to obtain better characteristics.

Brake device 10 is naturally not limited to those shown in FIG.

  As described above, the present invention has been described with the embodiment. However, the present invention is not limited to this, and it is naturally possible to adopt various configurations without departing from the gist of the present invention.

DESCRIPTION OF SYMBOLS 10 ... Brake apparatus 11 ... Cylinder mechanism 12 ... Pedal 13L, 13R ... Pedal simulator 26L, 26R, 38L, 38R, 72 ... Piston 70 ... Housing 72a ... End surface 73 ... Liquid chamber 74, 86 ... Plug 74a ... Communication hole 76 ... Transmission member 78 ... support member 80 ... support shafts 82a and 82b ... first spring members 84a and 84b ... second spring members 90 and 92 ... disc springs 90a and 92a ... inner slopes 94 and 96 ... rings

Claims (3)

A housing;
A piston that is slidably held in the housing and forms a fluid chamber through which hydraulic fluid is guided;
A cylinder mechanism comprising a plurality of disc springs for urging the piston toward the liquid chamber;
Among the plurality of disc springs, the bottom surfaces of at least two disc springs are arranged to face each other, and a circular member is provided that makes an arc contact with the inner surface of the disc springs arranged so that the bottom surfaces face each other. Cylinder mechanism. The cylinder mechanism according to claim 1,
The cylinder mechanism is characterized in that the circular member is movable in an axial direction and is arranged in a state in which movement is restricted in a direction orthogonal to the axial direction. A housing;
A piston that is slidably held in the housing and forms a fluid chamber through which hydraulic fluid is guided;
A cylinder mechanism comprising a plurality of disc springs for urging the piston toward the liquid chamber;
Among the plurality of disc springs, the bottom surfaces of at least two disc springs are arranged to face each other, and the movement prevention for preventing movement of the disc springs arranged so that the bottom surfaces face each other in a direction perpendicular to the axial direction. A cylinder mechanism comprising means.

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