JP6575487B2 - Pulsation reduction device and hydraulic pressure control device - Google Patents

Description

  The present invention relates to a pulsation reducing device and a hydraulic pressure control device using the pulsation reducing device.

  Conventionally, for example, a pulsation reducing device for reducing pulsation of fluid and a hydraulic pressure control device using the pulsation reducing device disclosed in Patent Literature 1, Patent Literature 2, and Patent Literature 3 are known. These conventional pulsation reducing devices have an elastic member for reducing pulsation, and the elastic member constitutes a part of the hydraulic path.

Japanese Patent Laid-Open No. 11-304076 German Patent Application Publication No. 19626305 JP-A-9-132126

  By the way, in each of the above conventional pulsation reducing devices, the elastic member (attenuating member) constitutes a part of the hydraulic path (passage), so the elastic member (attenuating member) is against the metal housing. Touch directly. Generally, an elastic member (attenuating member) is formed of a soft material in order to expand and contract in accordance with fluid pulsation. For this reason, it is necessary to prevent the elastic member (attenuation member) from being damaged and to be fixed to the housing during assembly.

  The present invention has been made to solve the above-described problems, and provides a pulsation reducing device capable of preventing the damping member from being damaged and a hydraulic pressure control device using the pulsation reducing device.

  In order to solve the above-mentioned problem, the invention of a pulsation reducing device according to claim 1 is a pulsation reducing device for reducing pulsation generated in a flowing fluid, wherein an inlet for inflowing fluid and an outlet for outflowing fluid are provided. And a housing having a housing hole communicating with the inlet and the outlet, and a bottomed housing accommodated in the housing hole so as to define a flow space through which the fluid flows through the inlet and the outlet. The cylindrical case, the holding member that holds the case inside the accommodation hole and liquid-tightly seals the opening of the accommodation hole, and the circulation space and the internal space of the case defined by the case and the holding member are communicated with each other. A communication path that circulates a part of the fluid flowing through the flow space to the internal space; and a damping member that is disposed in the internal space of the case and attenuates pulsation transmitted through the fluid that has flowed into the internal space. .

  According to this, the attenuation member can be accommodated inside the case. Therefore, when the damping member is assembled to the housing, it is possible to reliably prevent the damping member from being damaged by coming into contact with the corner portion or the like of the housing.

It is sectional drawing which shows the structure of the pulsation reduction apparatus which concerns on embodiment of this invention. It is a block diagram of the case of FIG. It is sectional drawing which shows the action | operation of the pulsation reduction apparatus of FIG. It is sectional drawing which shows the structure of the pulsation reduction apparatus which concerns on the 1st modification of embodiment. It is sectional drawing which shows the structure of the pulsation reduction apparatus which concerns on the 2nd modification of embodiment. It is sectional drawing which shows the structure of the pulsation reduction apparatus which concerns on the 3rd modification of embodiment. It is a block diagram of the hydraulic-pressure control apparatus of the brake device with which a pulsation reduction apparatus is applied. It is a block diagram which shows the modification of the hydraulic-pressure control apparatus of FIG.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. In the following embodiments and each modification, the same or equivalent parts are denoted by the same reference numerals in the drawings. Each figure used for explanation is a concept, and the shape of each part may not necessarily be exact.

  The pulsation reducing device 10 of this embodiment includes a housing 11 as shown in FIG. The housing 11 is made of a metal material and has an inflow port 11a through which a fluid flows in and an outflow port 11b through which the fluid flows out. The inflow port 11a allows, for example, a fluid discharged from a piston pump with pressure fluctuation (or discharge amount fluctuation) to flow in. The outflow port 11b allows the fluid with reduced pulsation generated due to pressure fluctuation (or discharge amount fluctuation) to flow out. The housing 11 has a receiving hole 11c that communicates with the inflow port 11a and the outflow port 11b. The accommodation hole 11c has a step portion 11c1 formed in the circumferential direction at the inner peripheral portion.

  The case 12 is accommodated in the accommodation hole 11c. The case 12 is made of a metal material or a resin material, and is provided in a bottomed cylindrical shape as shown in FIG. When the case 12 is housed in the housing hole 11c, the case 12 defines a circulation space R1 that communicates with the inflow port 11a and the outflow port 11b in the inside of the housing hole 11c. That is, the case 12 constitutes a flow path in which the outer periphery of the case 12 flows from the inlet 11a toward the outlet 11b inside the accommodation hole 11c. The open end of the case 12 has an annular protrusion 12a that protrudes outward in the radial direction from the outer periphery. The protruding portion 12a is accommodated in a step portion 11c1 provided on the inner peripheral portion of the accommodation hole 11c. Further, as shown in FIG. 2, the opening end of the case 12 is provided with notches 12b formed at a plurality of locations (for example, four locations) in the circumferential direction by notching a part of the opening end. It has been.

  Further, the housing 11 is provided with a plug 13 as a holding member as shown in FIG. The plug 13 is formed in a disk shape from a metal material, blocks communication between the accommodation hole 11c and the outside of the housing 11, and seals the opening of the accommodation hole 11c in a liquid-tight manner. The plug 13 is fixed to the housing 11 by, for example, caulking, screwing, press-fitting, or the like in a state in which the protruding portion 12a of the case 12 accommodating a bladder 15 described later is accommodated in the step portion 11c1 of the accommodation hole 11c. . In the present embodiment, the plug 13 is fixed by caulking the peripheral portion of the opening of the housing hole 11c of the housing 11 over the entire circumference (indicated by a broken circle shown only on one side in FIG. 1). (See enclosed area). As a result, in the case 12, the protruding portion 12a is held between the stepped portion 11c1 and the plug 13 and held in the accommodation hole 11c, and the plug 13 defines the internal space R2.

  As shown in FIG. 1, the circulation space R <b> 1 and the internal space R <b> 2 are communicated with each other through the communication path 14. The communication path 14 is provided between each notch 12 b formed at the opening end of the case 12 and the plug 13. The communication path 14 directs a part of the fluid flowing through the circulation space R1, that is, the fluid branched by flowing the fluid flowing into the circulation space R1 from the inflow port 11a into the inner space R2. To distribute. Moreover, the communication path 14 distribute | circulates the fluid in internal space R2 toward distribution space R1.

  The bladder 15 as a damping member is disposed in the internal space R2 of the case 12. The bladder 15 is made of an elastic material (for example, a rubber material), and has a bottomed cylindrical main body 15a as shown in FIG. The main body 15a is provided with an annular protrusion 15b that protrudes outwardly from the outer peripheral portion at the opening end. The outer diameter of the annular protrusion 15 b is provided so as to be larger than the inner diameter of the case 12. Thereby, the bladder 15 is accommodated in the internal space R2 of the case 12 in a state of being in close contact with the outer peripheral portion of the annular protrusion 15b and the inner peripheral portion of the case 12. That is, the bladder 15 is held on the inner peripheral portion of the case 12 by the elastic force of the annular protrusion 15b.

  The bladder 15 has an inner peripheral portion of the case 12, an outer peripheral portion of the main body portion 15 a, and an annular protruding portion 15 b in the internal space R <b> 2 of the case 12 by the outer peripheral portion of the annular protruding portion 15 b being in close contact with the inner peripheral portion of the case 12. The gas chamber R3, in which the gas is hermetically sealed, is partitioned. Therefore, the main body 15a of the bladder 15 is filled with the fluid flowing into the internal space R2 via the communication path 14, and the gas chamber R3 is filled with gas (for example, air). As a result, the bladder 15 compresses / decompresses the gas enclosed in the gas chamber R3 as the main body 15a expands / contracts according to the pulsation of the fluid, as will be described later. As a result, the pulsation of the fluid is attenuated.

  In the pulsation reducing device 10 configured in this way, as shown in FIG. 3, for example, fluid discharged from a piston pump that is a hydraulic power source flows into the circulation space R1 from the inflow port 11a, and the inside of the circulation space R1 Filled with fluid, the fluid flows out from the outlet 11b. In this case, since the circulation space R1 is formed by the housing hole 11c of the housing 11 and the outer peripheral portion of the case 12, most of the fluid flowing in from the inflow port 11a is indicated by a thick arrow in FIG. Then, it circulates in contact with the outer periphery of the case 12 and flows out from the outlet 11b.

  In addition, as indicated by thin arrows in FIG. 3, a part of the fluid that has flowed into the circulation space R <b> 1 reaches the communication path 14 through between the inner peripheral portion of the accommodation hole 11 c and the outer peripheral portion of the case 12. To do. The reached fluid flows into the internal space R2 formed inside the case 12 through the communication path 14, and fills the inside of the main body portion 15a of the bladder 15 forming the internal space R2. As described above, in a state where the fluid is filled in the circulation space R1 and the internal space R2, the fluid flowing from the inflow port 11a is caused by pressure fluctuation (or discharge amount fluctuation) in which high pressure and low pressure fluctuate periodically. When the pulsation occurs, the pulsation is transmitted to the fluid filling the main body portion 15a.

  In this case, when pressure fluctuation occurs from low pressure to high pressure and pulsation is transmitted, the pressure of the fluid filled in the internal space R2 is increased by the pulsation, so that the main body portion 15a of the bladder 15 expands outward (that is, , The volume inside the main body 15a is enlarged), and the gas in the gas chamber R3 is compressed. As a result, when the pressure of the fluid increases, the bladder 15 expands and compresses the gas in the gas chamber R3, thereby reducing the pressure of the fluid. As a result, the pressure of the fluid in the circulation space R1 that communicates with the internal space R2 via the communication path 14 also decreases (or the fluid in the circulation space R1 decreases), so that the circulation space R1 passes through the outlet 11b. The pulsation of the flowing fluid is reduced (damped).

  On the other hand, when pressure fluctuation occurs from high pressure to low pressure and the pulsation is transmitted, the pressure of the fluid filled in the internal space R2 is reduced by the pulsation, so the main body portion 15a of the bladder 15 compresses the gas in the gas chamber R3. To cancel. Thereby, the main body 15a contracts inward (that is, the internal volume of the main body 15a is reduced) by the pressure of the gas in the gas chamber R3, and the fluid in the internal space R2 passes through the communication path 14. Outflow toward the distribution space R1. As a result, the pressure of the fluid in the circulation space R1 that communicates with the internal space R2 via the communication path 14 is also increased (or the fluid in the circulation space R1 increases), so that the circulation space R1 passes through the outlet 11b. The pulsation of the fluid flowing out is reduced (attenuated).

  As can be understood from the above description, the pulsation reducing device 10 of the above-described embodiment is a pulsation reducing device that reduces pulsation generated in a flowing fluid, and includes an inflow port 11a through which the fluid flows in and a flow through which the fluid flows out. A housing 11 having an outlet 11b, an inflow port 11a, and an accommodation hole 11c communicating with the outflow port 11b, and a circulation space R1 that communicates with the inflow port 11a and the outflow port 11b and circulates fluid are defined inside the accommodation hole 11c. A bottomed cylindrical case 12 housed in the housing hole 11c, and a plug 13 which is a holding member that holds the case 12 inside the housing hole 11c and seals the opening of the housing hole 11c in a liquid-tight manner, A part of the fluid flowing through the flow space R1 is circulated to the internal space R2 by connecting the flow space R1 and the internal space R2 of the case 12 partitioned by the case 12 and the plug 13. Includes a communication passage 14, the bladder 15 is a damping member for attenuating pulsation transmitted through the fluid flowing is disposed in the internal space R2 in the case 12 in the internal space R2, a to.

  According to this, the case 12 of the pulsation reducing device 10 can constitute a circulation space R1 in which a fluid circulates inside the accommodation hole 11c communicating with the inflow port 11a and the outflow port 11b of the housing 11. And the bladder 15 can be accommodated in the case 12 which comprises the distribution space R1. In addition, the bladder 15 can partition the internal space R2 and the gas chamber R3 in an airtight manner inside the case 12. Thereby, the bladder 15 can reduce (attenuate) pulsation caused by pressure fluctuation (or discharge quantity fluctuation) in the internal space R2 and the circulation space R1 communicating with the internal space R2 via the communication passage 14. .

  By the way, the case 12 forms a circulation space R1 in which the fluid circulates, so that it is not directly exposed to the fluid in which the bladder 15 circulates. Therefore, the possibility that the bladder 15 is worn or damaged due to friction with the circulating fluid or contact with a hard foreign substance flowing with the fluid is reduced, and the bladder 15 reduces (attenuates) pulsation over a long period of time. be able to. Further, since the bladder 15 is accommodated in the case 12, it does not directly contact the housing 11. Therefore, for example, even if the bladder 15 falls off in the case 12, it is possible to reliably prevent the outlet 11b communicating with the circulation space R1 from being blocked. Furthermore, since the bladder 15 is accommodated in the case 12, when assembling the bladder 15 to the housing 11, for example, it is possible to reliably prevent the bladder 15 from being damaged by coming into contact with the corners of the housing 11 or the like.

  Further, in this case, the plug 13 as a holding member is provided with a protruding portion 12a provided at the opening end portion of the case 12 and protruding outward in the radial direction of the case 12 on the inner peripheral portion of the accommodation hole 11c. Is held by the stepped portion 11c1.

  According to this, the case 12 is securely held in the housing 11 by the plug 13. Thereby, the case 12 can reliably configure the circulation space R1 and can hold the bladder 15 with certainty. Therefore, the bladder 15 accommodated inside the case 12 reduces pulsation caused by pressure fluctuation (or discharge quantity fluctuation) in the internal space R2 and the circulation space R1 communicating with the internal space R2 via the communication passage 14. Can be (attenuated).

  In these cases, the communication path 14 is provided between the notch 12b provided by notching a part of the opening end of the case 12 and the plug 13 as a holding member.

  According to this, by providing the notch 12b at the opening end of the case 12, the communication path 14 can be provided very easily. Accordingly, the communication space 14 can reliably connect the circulation space R1 and the internal space R2, so that the bladder 15 can reliably reduce (attenuate) pulsation generated in the fluid.

  In these cases, the bladder 15 as a damping member is made of an elastic material, and defines a gas chamber R3 in which gas is sealed in the internal space R2 of the case 12 so as to attenuate pulsation.

  According to this, when pulsation is transmitted to the fluid filling the internal space R2, the bladder 15 accommodated in the internal space R2 of the case 12 expands or contracts by compressing or decompressing the gas in the gas chamber R3. can do. Therefore, the bladder 15 can satisfactorily reduce (attenuate) pulsation generated in the fluid.

  In this case, the bladder 15 as a damping member includes a bottomed cylindrical main body portion 15a and an annular protrusion 15b protruding outward from the main body portion 15a at the opening end of the main body portion 15a. The outer periphery of the protrusion 15b and the inner periphery of the case 12 are hermetically sealed, and the inner periphery of the case 12, the outer periphery of the main body 15a, and the annular protrusion 15b pulsate into the internal space R2 of the case 12. The gas chamber R3 that attenuates is partitioned.

  According to this, by assembling the bladder 15 inside the case 12, the internal space R2 and the gas chamber R3 can be reliably partitioned. Thereby, when the pulsation is propagated to the fluid filling the inside of the main body portion 15a forming the internal space R2, the main body portion 15a of the bladder 15 expands or contracts by compressing or decompressing the gas in the gas chamber R3. can do. Therefore, it is possible to satisfactorily reduce (attenuate) pulsation generated in the fluid.

(First modification of the above embodiment)
In the above embodiment, the bladder 15 is brought into close contact with the inner peripheral portion of the case 12 and held by the inner peripheral portion of the case 12 by the elastic force of the annular protrusion 15b provided on the outer peripheral portion. Further, the bladder 15 is configured to partition the internal space R2 and the gas chamber R3 by the annular protrusion 15b being in close contact with the inner peripheral portion of the case 12. In this case, as shown in FIG. 4, it is also possible to insert the core 16 as a core member into the opening end of the main body 15a of the bladder 15 as necessary. Hereinafter, this first modification will be described.

  The core 16 as the core member is formed in a cylindrical shape having a small diameter portion 16a and a large diameter portion 16b from a metal material or a resin material. As for the core 16, the small diameter part 16a is inserted in the opening end part of the main-body part 15a of the bladder 15. FIG. The small-diameter portion 16a is provided so as to have a larger outer diameter than the open end of the main body portion 15a accommodated in the case 12, that is, the inner diameter of the annular protrusion 15b. When the core 16 is inserted into the open end of the main body 15 a while the bladder 15 is housed in the case 12, the small-diameter portion 16 a presses the annular protrusion 15 b toward the inner peripheral portion of the case 12. As a result, the annular protrusion 15 b of the bladder 15 is sandwiched (compressed) by the inner peripheral portion of the case 12 and the outer peripheral portion of the small diameter portion 16 a of the core 16. As a result, the bladder 15 is more firmly held with respect to the case 12, and the inner peripheral portion of the case 12 and the annular protrusion 15b seal the gas chamber R3 in a more airtight manner.

  The core 16 has a through hole 16c communicating with the inside of the main body portion 15a of the bladder 15, that is, the internal space R2. The core 16 has a plurality of groove portions 16d communicating with the through holes 16c on the surface of the large diameter portion 16b facing the plug 13. As a result, the fluid from the communication path 14 flows into and out of the main body portion 15a, which is the internal space R2, via the through hole 16c and the groove portion 16d of the core 16.

  Therefore, in this first modified example, a small-diameter portion that is disposed at the opening end of the body portion 15a of the bladder 15 that is a damping member and presses the outer peripheral portion of the annular protrusion 15b toward the inner peripheral portion of the case 12. The core 16 which is a core member which has 16a and the through-hole 16c which makes the fluid in internal space R2 flow into the inside of the main-body part 15a is provided.

  Thereby, the bladder 15 can be reliably held with respect to the case 12. Further, since the annular protrusion 15b of the bladder 15 is pressed and sandwiched between the inner peripheral portion of the case 12 and the small-diameter portion 16a of the core 16, gas is more reliably sealed in the internal space R2. Chamber R3 can be partitioned. Therefore, the main body portion 15a of the bladder 15 can be reliably expanded or contracted by compressing or releasing the gas in the gas chamber R3. Therefore, it is possible to satisfactorily reduce (attenuate) pulsation generated in the fluid.

(Second modification of the above embodiment)
In the above embodiment, the bladder 15 is constituted by the bottomed cylindrical main body 15a and the annular protrusion 15b provided on the outer peripheral portion of the main body 15a. Accordingly, the bladder 15 partitions the internal space R2 and the gas chamber R3 inside the case 12. In this case, as shown in FIG. 5, it is also possible to use a hollow spherical bladder 17 made of an elastic material (for example, a rubber material) as the damping member accommodated in the case 12. The number of hollow spherical bladders 17 accommodated in the case 12 may be plural.

  In this case, the diameter of the bladder 17 is set to be smaller than the inner diameter of the case 12. Thus, the bladder 17 hermetically partitions the internal space R2 outside the bladder 17 and the gas chamber R3 inside the bladder 17 inside the case 12.

  In this case, when a pulsation that varies from low pressure to high pressure is transmitted, the pressure of the fluid filled in the internal space R2 is increased by the pulsation, so that the bladder 17 contracts inward (that is, the internal volume of the bladder 17). And the gas in the gas chamber R3 is compressed. Thereby, when the pressure of the fluid becomes high, the bladder 17 contracts and compresses the gas in the gas chamber R3, thereby reducing the pressure of the fluid. As a result, the pressure of the fluid in the circulation space R1 that communicates with the internal space R2 via the communication path 14 also decreases (or the fluid in the circulation space R1 decreases), so that the circulation space R1 passes through the outlet 11b. The pulsation of the flowing fluid is reduced (damped).

  On the other hand, when a pulsation that varies from a high pressure to a low pressure is transmitted, the pressure of the fluid filled in the internal space R2 is reduced by the pulsation, so the bladder 17 releases the compression of the gas in the gas chamber R3. As a result, the bladder 17 expands outward (that is, the volume inside the bladder 17 expands) due to the pressure of the gas in the gas chamber R3, and increases the pressure of the fluid in the internal space R2. As a result, the pressure of the fluid in the circulation space R1 that communicates with the internal space R2 via the communication path 14 is also increased (or the fluid in the circulation space R1 increases), so that the circulation space R1 passes through the outlet 11b. The pulsation of the fluid flowing out is reduced (attenuated).

  Therefore, also in this second modified example, the same effect as in the above embodiment can be obtained. When the bladder 17 is separated from the case 12 as in the second modification, the communication path 14 can be formed at an arbitrary position in a portion of the case 12 that does not face the inflow path 11a.

(Third modification of the above embodiment)
In the above embodiment, for example, as shown in FIGS. 1 and 4, the fluid is allowed to flow out of the circulation space R1 without increasing the inner diameter of the outlet 11b, that is, without narrowing the flow path. In this case, as shown in FIG. 6, it is possible to reduce the inner diameter of the outlet 11b so that the outlet 11b functions as an orifice.

  Thus, even if the outflow port 11b functions as an orifice, the bladder 15 is accommodated inside the case 12, so that the fluid flowing through the circulation space R1 from the inflow port 11a toward the outflow port 11b is not detected. Contact is prevented. Further, in this case, since resistance is applied when the fluid flows out from the circulation space R1, pulsation is easily transmitted to the bladder 15, and as a result, pulsation generated in the fluid in the circulation space R1 is reliably reduced (damped). )can do. Therefore, also in the case of this third modification, the same effect as in the above embodiment can be obtained.

  By the way, the pulsation reducing device 10 described in the above embodiment and each modification can be applied to, for example, a damper used in a hydraulic pressure control device constituting a vehicle brake control system. Hereinafter, a brake control system to which the pulsation reducing device 10 can be applied will be briefly described with reference to FIG.

  In the brake control system, the pulsation reducing device 10 is incorporated in an actuator 5 that is a hydraulic pressure control device. The brake control system includes, as the cylinder mechanism 23, a master cylinder (M / C) 230 (master cylinder), master pistons 231 and 232, and a master reservoir 233. The wheel cylinders 24, 25, 26, and 27 (wheel cylinders) are disposed on the left rear wheel RL, the right rear wheel RR, the left front wheel FL, and the right front wheel FR, respectively, and apply braking force. The master cylinder 230 and the wheel cylinders 24 to 27 are connected via the actuator 5.

  The actuator 5 is a device that controls the hydraulic pressure (hereinafter referred to as “wheel pressure”) of the wheel cylinders 24 to 27 in accordance with an instruction from the brake control device 6. Specifically, the actuator 5 includes a hydraulic circuit 50 as shown in FIG. The hydraulic circuit 50 includes a first piping system 50a and a second piping system 50b. The first piping system 50a is a system that controls the wheel pressure applied to the left rear wheel RL and the right rear wheel RR. The second piping system 50b is a system that controls the wheel pressure applied to the left front wheel FL and the right front wheel FR.

  The first piping system 50a includes a main pipe A that is a first flow path, a differential pressure control valve 51 that is an electromagnetic valve, pressure increase valves 52 and 53 that are electromagnetic valves, a pressure reduction pipe B, and a pressure reduction that is an electromagnetic valve. Valves 54 and 55, a pressure regulating reservoir 56, a reflux pipe C that constitutes a second flow path, and an auxiliary pipe D are provided. The differential pressure control valve 51 can control the differential pressure between the hydraulic pressure on the master cylinder 230 side (master cylinder side) and the hydraulic pressure on the wheel cylinders 24 and 25 side (wheel cylinder side). The brake control device 6 is provided so as to be able to control these electromagnetic valves.

  The reflux line C is a pipe that connects the pressure reducing line B (or the pressure regulating reservoir 56) and a portion between the differential pressure control valve 51 and the pressure increasing valves 52 and 53 in the main line A that is the first flow path. Road. The pump 57 is a pump driven by the motor 8 and is provided in the reflux pipe C. A fluid (brake fluid) is supplied from the pressure regulating reservoir 56 to the master cylinder side or the wheel cylinder side via the reflux pipe C. Fluidize. The damper 7 is disposed on the discharge side of the pump 57 in the reflux line C, that is, on the discharge side path C1 of the return line C constituting the second flow path.

  In this case, the pulsation reducing device 10 shown in the above embodiment and each of the above modifications can be applied to the damper 7.

  When the pulsation reducing device 10 described above is applied to the damper 7 of the vehicle brake control system, the pulsation reducing device 10 generates pulsations caused by pressure fluctuations (or fluctuations in the discharge amount) of the brake fluid discharged from the pump 57. It can be reduced (attenuated). And when the inflow port 11a and the outflow port 11b are connected to the discharge side channel | path C1 of the recirculation | reflux pipe line C, since the case 12 forms the distribution | circulation space R1 where a brake fluid distribute | circulates, the brake fluid which the bladders 15 and 17 distribute | circulate Is not directly exposed to.

  Therefore, the possibility that the bladders 15 and 17 are worn due to friction with the circulating brake fluid and contact with hard foreign matter circulating with the brake fluid is reduced, and the bladders 15 and 17 can reduce pulsation over a long period of time. it can. Further, since the bladders 15 and 17 are accommodated in the case 12, for example, even when the bladders 15 and 17 drop off, it is possible to reliably prevent the discharge side passage C1 of the reflux conduit C from being blocked. Further, since the bladders 15 and 17 are accommodated in the case 12, it is possible to effectively prevent the bladders 15 and 17 from being damaged when the bladders 15 and 17 are assembled to the housing (block) of the actuator 5.

  In this case, as shown in FIG. 8, it is possible to provide a switching orifice in the discharge side passage C1 of the brake fluid (fluid) flowing out from the damper 7 (pulsation reducing device 10). Thereby, when the pressure in the circulation space R1 in the damper 7 (pulsation reducing device 10) is increased by the orifice 58, the check valve 59 is opened, so that the brake fluid is passed through the damper 7 (pulsation reducing device 10). (Fluid) can be circulated.

  In carrying out the present invention, the present invention is not limited to the above embodiment and each of the above modifications, and various modifications can be made without departing from the object of the present invention.

  For example, in the above embodiment, the bladder 15 is held on the inner peripheral portion of the case 12 by the elastic force of the annular protrusion 15 b of the bladder 15. In this case, for example, an annular or a plurality of protrusions can be provided on the inner peripheral portion of the case 12 so as to position the bladder 15.

  Moreover, in the said embodiment and said each modification, case 12 was made into the bottomed cylindrical shape. In this case, the shape of the case 12 may be any shape as long as it has a bottomed cylindrical shape.

  Furthermore, in the embodiment and the first modification, the main body portion 15a of the bladder 15 has a bottomed cylindrical shape. In this case, the shape of the main body portion 15a of the bladder 15 may be any shape as long as it has a bottomed cylindrical shape capable of airtightly partitioning the internal space R2 and the gas chamber R3.

DESCRIPTION OF SYMBOLS 5 ... Actuator, 6 ... Brake control device, 7 ... Damper, 8 ... Motor, 10 ... Pulsation reduction device, 11 ... Housing, 11a ... Inlet, 11b ... Outlet, 11c ... Housing hole, 11c1 ... Step part, 12 ... Case, 12a ... Projection, 12b ... Notch, 13 ... Plug (holding member), 14 ... Communication path, 15 ... Bladder (attenuation member), 15a ... Body part, 15b ... Annular projection, 16 ... Core (core) Member), 16a ... small diameter portion, 16b ... large diameter portion, 16c ... through hole, 16d ... groove, 17 ... bladder (damping member), 50 ... hydraulic circuit, 50a ... first piping system, 57 ... pump, 58 ... orifice , 59 ... Check valve, A ... Main pipe (first flow path), C ... Reflux pipe (second flow path), C1 ... Discharge side passage (second flow path), R1 ... Distribution space, R2 ... Internal space , R3 ... Gas chamber

Claims (9)

A pulsation reducing device for reducing pulsation generated in a circulating fluid,
A housing having an inlet through which the fluid flows in and an outlet through which the fluid flows out, and an accommodation hole communicating with the inlet and the outlet;
A bottomed cylindrical case that is accommodated in the accommodation hole so as to define a flow space through which the fluid flows and communicates with the inflow port and the outflow port in the accommodation hole;
While holding the case inside the accommodation hole, a holding member for sealing the opening of the accommodation hole in a liquid-tight manner,
A communication path that communicates the flow space and the internal space of the case defined by the case and the holding member, and distributes a part of the fluid flowing through the flow space to the internal space;
A damping member that is disposed in the internal space of the case and attenuates the pulsation transmitted through the fluid that has flowed into the internal space ;
The communication path is
A pulsation reducing device provided between a notch portion provided by notching a part of an opening end portion of the case and the holding member . The holding member is
The protrusion part which is provided in the opening edge part of the said case and protrudes outward in the radial direction of the said case is hold | maintained at the step part provided in the inner peripheral part of the said accommodation hole. Pulsation reduction device. The damping member is
The pulsation reducing device according to claim 1 , wherein the pulsation reducing device is made of an elastic material and defines a gas chamber in which gas is sealed so as to attenuate the pulsation in the internal space of the case. The damping member is
A bottomed tubular body,
An annular protrusion protruding in an annular shape toward the outside of the main body at the opening end of the main body;
The outer peripheral portion of the annular protrusion and the inner peripheral portion of the case are hermetically sealed, and the inner space of the case is formed by the inner peripheral portion of the case, the outer peripheral portion of the main body portion, and the annular protrusion. The pulsation reducing device according to claim 3 , wherein the gas chamber is divided into two. Arranged at the opening end of the main body of the damping member,
And a small diameter portion which presses the outer peripheral portion of the annular projection on the inner peripheral portion of the case, a through hole for flowing the fluid in said inner space inside said main body portion, a core member having a The pulsation reduction device according to claim 4 provided. Provided in the first flow path connecting the master cylinder and the wheel cylinder, and controls the differential pressure between the hydraulic pressure at the master cylinder side of the first flow path and the hydraulic pressure at the wheel cylinder side of the first flow path A configured solenoid valve;
A pump that discharges the brake fluid of the master cylinder to a portion between the solenoid valve and the wheel cylinder of the first flow path via a second flow path;
A hydraulic pressure control device comprising: the pulsation reducing device according to any one of claims 1 to 5 disposed in the second flow path. A pulsation reducing device for reducing pulsation generated in a circulating fluid,
A housing having an inlet through which the fluid flows in and an outlet through which the fluid flows out, and an accommodation hole communicating with the inlet and the outlet;
  A bottomed cylindrical case that is accommodated in the accommodation hole so as to define a flow space through which the fluid flows and communicates with the inflow port and the outflow port in the accommodation hole;
  While holding the case inside the accommodation hole, a holding member for sealing the opening of the accommodation hole in a liquid-tight manner,
  A communication path that communicates the flow space and the internal space of the case defined by the case and the holding member, and distributes a part of the fluid flowing through the flow space to the internal space;
  A damping member that is disposed in the internal space of the case and attenuates the pulsation transmitted through the fluid that has flowed into the internal space;
  The damping member is
  A gas chamber made of an elastic material and defining a gas chamber in which gas is sealed so as to attenuate the pulsation in the internal space of the case,
  A bottomed tubular body,
  An annular protrusion protruding in an annular shape toward the outside of the main body at the opening end of the main body;
  The outer peripheral portion of the annular protrusion and the inner peripheral portion of the case are hermetically sealed, and the inner space of the case is formed by the inner peripheral portion of the case, the outer peripheral portion of the main body portion, and the annular protrusion. A pulsation reducing device for partitioning the gas chamber.   Arranged at the opening end of the main body of the damping member,
  A core member having a small-diameter portion that presses the outer peripheral portion of the annular protrusion toward the inner peripheral portion of the case, and a through-hole through which the fluid in the internal space flows into the main body portion; The pulsation reduction device according to claim 7 provided.   Provided in the first flow path connecting the master cylinder and the wheel cylinder, and controls the differential pressure between the hydraulic pressure at the master cylinder side of the first flow path and the hydraulic pressure at the wheel cylinder side of the first flow path A configured solenoid valve;
  A pump that discharges the brake fluid of the master cylinder to a portion between the solenoid valve and the wheel cylinder of the first flow path via a second flow path;
  A hydraulic pressure control device comprising: the pulsation reducing device according to claim 7 or 8 disposed in the second flow path.

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