master cylinder

Abstract

Disclosed is a master cylinder. The master cylinder according to the present embodiment includes a hydraulic module having a main hole formed in an axial direction inside; a first piston inserted into the main hole on one side and capable of displacement, the other side exposed to the outside of the hydraulic module and connected to a brake pedal; a second piston inserted into the inside of the first piston in the main hole and capable of displacement; an elastic member provided between the first piston and the second piston for providing a pedal feel; and a mounting seat having a sub hole formed in an axial direction inside, the first piston inserted and passing through the sub hole and capable of displacement, one side surface of the mounting seat combined with the other side surface of the hydraulic module, wherein the hydraulic module includes at least one hydraulic flow path passing through the other side surface, and the mounting seat includes a connection flow path connecting the sub hole and the hydraulic flow path.

Description

Technical Field

[0001] This invention relates to a master cylinder, and more specifically, to a master cylinder that achieves operational reliability while reducing operating noise and vibration. Background Technology

[0002] Vehicles are always equipped with braking systems to perform braking, and recently various types of systems have been proposed to obtain more powerful and stable braking force.

[0003] According to existing braking systems, when the driver presses the brake pedal, a mechanically connected booster supplies the hydraulic pressure required for braking to the wheel cylinders. However, recently, electronic braking systems have been widely used. When the driver presses the brake pedal, a pedal displacement sensor that senses the displacement of the brake pedal receives the driver's braking intention in the form of an electrical signal, thereby supplying the hydraulic pressure required for braking to the wheel cylinders.

[0004] This electronic braking system includes a master cylinder connected to the brake pedal to generate hydraulic pressure through the pedal force of the brake pedal, a pedal stroke sensor that senses the displacement of the brake pedal, a hydraulic supply device that generates hydraulic pressure medium by starting a motor based on the information sensed by the pedal stroke sensor, and an oil pressure control unit that supplies the hydraulic pressure generated by the hydraulic supply device to the wheel cylinders after adjustment. Summary of the Invention

[0005] Technical problems to be solved

[0006] This embodiment aims to provide a master cylinder with improved operational reliability and performance.

[0007] This embodiment aims to provide a master cylinder that can reduce noise and vibration generated during piston displacement.

[0008] This embodiment aims to provide a master cylinder capable of maintaining a constant piston stroke.

[0009] This embodiment aims to provide a master cylinder that can prevent leakage of pressurized medium and inflow of impurities.

[0010] This embodiment aims to provide a master cylinder that can improve product durability by mitigating the impact applied to component elements.

[0011] This embodiment aims to provide a master cylinder that enables product assemblability and miniaturization.

[0012] means of solving technical problems

[0013] According to one aspect of the invention, a master cylinder can be provided, comprising: a hydraulic module having a main bore formed along an axial direction therein; a first piston having one side inserted into the main bore for displacement, and the other side exposed to the outside of the hydraulic module and connected to a brake pedal; a second piston being inserted into the main bore to the inner side of the first piston for displacement; an elastic member between the first piston and the second piston for providing pedal feel; and a mounting base having a secondary bore formed along an axial direction therein, the first piston being inserted into and passing through the secondary bore for displacement, one side of the mounting base being coupled to the other side of the hydraulic module, wherein the hydraulic module includes at least one hydraulic flow path passing through the other side, and the mounting base includes a connecting flow path connecting the secondary bore and the hydraulic flow path.

[0014] The hydraulic flow path is formed on the hydraulic module at a certain distance from the main hole. One end of the connecting flow path is exposed on one side of the mounting base, while the other end is connected to the secondary hole and is formed by inclining at a certain angle relative to the axial direction.

[0015] It includes: an input rod, one end of which is connected to the first piston and the other end of which is connected to the brake pedal; a support plate, which is fixed to the input rod; and a cover, one end of which is supported by the mounting base and the other end of which is supported by the support plate, and is capable of telescopic movement, wherein the support plate includes an exhaust hole formed through the cover in a manner that connects the interior and exterior of the cover, and the exhaust hole is formed at a certain angle relative to the axial direction.

[0016] It may also include: a first seal, which is sandwiched between one side of the mounting base and the other side of the hydraulic module to seal the hydraulic flow path and the connecting flow path. The first seal extends along the periphery of the opening of the connecting flow path on one side of the mounting base or extends along the periphery of the opening of the hydraulic flow path on the other side of the hydraulic module.

[0017] The first seal mentioned above can be formed in a ring shape.

[0018] The first seal can be inserted into and placed in a first receiving groove recessed on the other side of the hydraulic module.

[0019] The first seal may include: a central first body portion; a first blade portion that protrudes inward from the first body portion toward the inner side adjacent to the hydraulic flow path; and a second blade portion that protrudes outward from the first body portion toward the outer side offset from the hydraulic flow path.

[0020] The outer peripheral surface of the second blade portion can be formed to correspond to the shape of the inner surface of the first receiving groove.

[0021] The cross-sectional shape of the first main body can be formed as a circle, and the thickness of the second blade portion can be formed to be smaller than the diameter of the first main body.

[0022] The hydraulic module may also include a shaft hole formed along the axial direction, and further include a second seal, which is sandwiched between one side of the mounting base and the other side of the hydraulic module, and seals the main hole and the shaft hole. The second seal extends along the periphery of the opening of the main hole and the opening of the shaft hole on the other side of the hydraulic module.

[0023] The aforementioned second seal can be inserted into and placed in a second receiving groove recessed on the other side of the aforementioned hydraulic module.

[0024] The second seal may include: a central second body portion; a third blade portion that protrudes from the second body portion toward the inner side adjacent to the main hole or the shaft hole; and a fourth blade portion that protrudes from the second body portion toward the outer side offset from the main hole or the shaft hole.

[0025] The outer peripheral surface of the fourth blade can be formed to correspond to the shape of the inner surface of the second receiving groove.

[0026] The cross-sectional shape of the second main body can be formed as a circle, and the thickness of the fourth blade is less than the diameter of the second main body.

[0027] The aforementioned secondary hole may also include a first step portion formed in a stepped shape at one end, and may also include a first bushing component inserted into the first step portion to guide the reciprocating movement of the first piston.

[0028] It may also include: a shock absorber component, at least a portion of which is capable of entering the inner side of the first step portion.

[0029] The main hole may include: a first hole formed to allow the first piston to be displaced; and a second hole formed inside the first hole to allow at least a portion of the second piston to be displaced, and having a diameter smaller than the diameter of the first hole, wherein the second hole includes a second step portion formed in a stepped shape at the other end facing the first hole, and further includes: a second bushing member inserted into the second step portion to guide the reciprocating movement of the second piston.

[0030] The aforementioned secondary hole may include a third step portion formed in a stepped shape at the other end, and may also include a third bushing component inserted into the third step portion to guide the reciprocating movement of the first piston.

[0031] The aforementioned second bushing component can be formed in an annular shape, including an inner groove recessed along the circumferential direction on its inner circumferential surface.

[0032] The first piston may include: a main body extending along the axial direction; and a connecting portion extending radially at one end of the main body, wherein the shock absorber component is configured such that one side is supported by the connecting portion and the other side can face and contact the first bushing component.

[0033] The aforementioned shock absorber component may include a plurality of recessed outer grooves on at least one of its sides.

[0034] The mounting base may include a mounting protrusion formed along the edge of one end of the secondary hole, wherein the outer peripheral surface of the mounting protrusion faces or contacts the inner peripheral surface of the main hole.

[0035] The hydraulic module may further include a connecting hole that connects the main hole and the shaft hole. The second piston includes a mounting platform that protrudes from the outer peripheral surface and may also include a first limiter that is located on the inner peripheral surface of the main hole. The mounting platform is mounted and supported, and has an open opening on one side. The connecting hole is located inside the opening.

[0036] The main hole may also include a first limiting groove formed by a recess along the circumferential direction on its inner circumferential surface, and at least a portion of the first limiting device is inserted into and placed in the first limiting groove.

[0037] The aforementioned first limiting groove may include an anti-detachment part protruding inside the aforementioned opening.

[0038] It includes: an input rod, one end of which is connected to the first piston and the other end of which is connected to the brake pedal; a support plate fixed to the input rod; a cover, one end of which is supported by the mounting base and the other end of which is supported by the support plate, and is capable of telescopic movement; and a piston spring, one end of which is supported by the mounting base and the other end of which is supported by the support plate, thereby elastically supporting the input rod or the first piston, wherein the inner circumferential surface of the cover is provided with an inwardly protruding noise-suppressing protrusion so as to maintain contact with at least a portion of the outer circumferential surface of the piston spring.

[0039] It may also include: a second limiter, which is provided on the outer peripheral surface of the first piston at a portion exposed to the outside of the mounting seat, wherein the second limiter includes a receiving portion located on the inside for the passage of the first piston and an opening formed on one side of the mounting.

[0040] The outer peripheral surface of the first piston can be formed into a cylindrical shape. The receiving portion includes a first center, a first receiving portion having a first radius from the first center, a second center, and a second receiving portion having a second radius from the second center. The second center is formed closer to the mounting opening than the first center, and the second radius is smaller than the first radius.

[0041] Invention Effects

[0042] The master cylinder according to this embodiment can improve the reliability and performance of operation.

[0043] The master cylinder according to this embodiment can reduce noise and vibration generated during piston displacement.

[0044] According to this embodiment, the master cylinder can maintain a constant piston stroke.

[0045] The master cylinder according to this embodiment can prevent leakage of pressurized medium and inflow of impurities.

[0046] The master cylinder according to this embodiment can mitigate the impact applied to component elements, thereby improving the durability of the product.

[0047] The master cylinder according to this embodiment enables the product to be assembled and miniaturized. Attached Figure Description

[0048] Figure 1 This is a perspective view showing the main cylinder according to this embodiment.

[0049] Figure 2 This is a cross-sectional view showing the main cylinder according to this embodiment.

[0050] Figure 3 This is a cut-out perspective view of the main cylinder according to this embodiment.

[0051] Figure 4 This is a cut perspective view showing the first piston according to this embodiment with a cover.

[0052] Figure 5 This is a perspective view showing the cover according to this embodiment.

[0053] Figure 6 This is a cut perspective view of the first piston according to this embodiment.

[0054] Figure 7 It is shown in magnification Figure 2 The diagram for part A.

[0055] Figure 8 It is shown in magnification Figure 2 The diagram in part B.

[0056] Figure 9 It is shown in magnification Figure 8 The diagram in section E is a cross-sectional view of the first seal according to this embodiment.

[0057] Figure 10 This is a diagram showing the state of deformation of the first seal according to this embodiment due to the hydraulic pressure of the pressurized medium.

[0058] Figure 11 This is a split perspective view of the second seal according to this embodiment.

[0059] Figure 12 It is shown in magnification Figure 8 The diagram of part F is a cross-sectional view of the second seal according to this embodiment.

[0060] Figure 13 as well as Figure 14 It is shown in magnification Figure 2 The diagram in Part A shows the forward and backward states of the first piston according to this embodiment.

[0061] Figure 15 This is a perspective view showing the first bushing component according to this embodiment.

[0062] Figure 16 This is a perspective view showing the shock absorber component according to this embodiment.

[0063] Figure 17 It is shown in magnification Figure 2 The diagram for part C.

[0064] Figure 18 This is a perspective view showing the second bushing component according to this embodiment.

[0065] Figure 19 This is a perspective view showing the third bushing component according to this embodiment.

[0066] Figure 20 This is a cut-out perspective view of the main cylinder according to this embodiment.

[0067] Figure 21 This is a side cross-sectional view of the main cylinder according to this embodiment, showing the state in which the mounting platform is supported by the first limiter.

[0068] Figure 22 It is shown in magnification Figure 21 The diagram for part G.

[0069] Figure 23 Cross-sectional views of the main hole, shaft hole, and connecting hole in other directions according to this embodiment are shown.

[0070] Figure 24A cross-sectional view in another direction is shown of the mounting platform according to this embodiment being supported by the first limiter.

[0071] Figure 25 It is shown in magnification Figure 2 The diagram for part D.

[0072] Figure 26 This is a side view showing the second limiter according to this embodiment in other directions.

[0073] Figure 27 yes Figure 25 The A-A' sectional view is a side view in another direction showing the second limiter installed on the first piston.

[0074] Marker description

[0075] 1: Main cylinder 100: Intermittent flow path

[0076] 101: First gap 102: Second gap

[0077] 103: Third Gap 103: Third Gap

[0078] 110: Hydraulic module; 111: First hole

[0079] 112: Second hole; 116: First seal

[0080] 117: Second seal; 118: Shaft hole

[0081] 119: Hydraulic flow path; 121: First piston

[0082] 123: Elastic component; 124: Second piston

[0083] 127: Cover; 140: Mounting bracket

[0084] 142: Secondary aperture; 144: Noise suppression protrusion

[0085] 145: Connecting flow path 146: Cover

[0086] 147: Support plate 147a: Vent hole

[0087] 148: Piston Spring 151: First Bushing Assembly

[0088] 152: Shock absorber component; 160: Second bushing component

[0089] 170: Third bushing component; 182: First limiter

[0090] 190: Second limit switch Detailed Implementation

[0091] Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings. The following embodiments are provided to fully convey the spirit of the invention to those skilled in the art. The present invention is not limited to the embodiments disclosed below and can be implemented in other ways. For clarity, parts unrelated to the description are omitted from the drawings, and the dimensions of constituent elements are sometimes exaggerated to aid understanding.

[0092] Figure 1 This is a perspective view showing the main cylinder 1 according to this embodiment. Figure 2 This is a cross-sectional view showing the main cylinder 1 according to this embodiment. Furthermore, Figure 3 This is a cut perspective view of the main cylinder 1 according to this embodiment.

[0093] Reference Figures 1 to 3 According to this embodiment, the main cylinder 1 includes: a hydraulic module 110 having main holes 111 and 112 in the axial direction inside; a first piston 121 configured to be inserted into the main holes 111 and 112 on one side and exposed to the outside of the hydraulic module 110 on the other side; a second piston 124 inserted into the inner side of the first piston 121 in the main holes 111 and 112; an elastic member 123 disposed between the first piston 121 and the second piston 124; a mounting base 140 in which the first piston 121 is inserted and penetrates and is coupled to the hydraulic module 110; a first seal 116 and a second seal 117 sandwiched between the hydraulic module 110 and the mounting base 140 to seal the flow path and prevent leakage of the pressurized medium; a cover 127 provided on the first piston 121; and a gap flow path 100 formed by the interval between the first piston 121 and the cover 127.

[0094] Hydraulic module 110 includes a portion extending along the axial direction and having an open side (to) Figure 2 Main holes 111 and 112 (based on the left side). Main holes 111 and 112 include: such that one side of the first piston 121 (described later) Figure 2 The first hole 111, which allows displacement, is inserted into the right side (as referenced), and is formed inside the first hole 111 (with the right side as referenced). Figure 2 The first hole 111 and the second hole 112 are arranged in series with reference to the axial direction, and the first hole 111 is disposed on the outside of the second hole 112 on the hydraulic module 110, and the second hole 112 is disposed on the inside of the first hole 111 on the hydraulic module 110. The diameter of the second hole 112 can be formed to be smaller than the diameter of the first hole 111, so that, as described later, the second hole 112 has a stepped end formed on the other side facing the first hole 111 (with the first hole 111 on the right side). Figure 2 The second step portion 112a (based on the left end).

[0095] In addition to the main bores 111 and 112 of the master cylinder 1 according to this embodiment, the hydraulic module 110 includes various flow paths for conveying pressurized medium. As an example, a through hydraulic flow path 119 can be provided on the other side of the hydraulic module 110, which can be connected to a check flow path side for checking whether the braking device is functioning properly, such as for leaks in the pressurized medium. That is, the hydraulic module 110 can be understood as a valve module constituting the braking system of a vehicle. The hydraulic module 110 can be fixed and supported on the vehicle body by a support bracket 130. Furthermore, as described later, the hydraulic module 110 may also have a shaft bore 118 for moving the shaft 20 of a displacement sensing device (not shown) that senses pedal displacement in the axial direction, and a connecting hole 118a connecting the main bores 111 and 112 with the shaft bore 118. (Refer to later...) Figures 20 to 24 This will be explained in detail.

[0096] It can be set to insert the first piston 121 into one side of the first hole 111 (to... Figure 2 The first piston 121 is capable of displacement along the axial direction (with the right side as a reference). The other side of the first piston 121 can be exposed to the outside of the hydraulic module 110 and passes through the mounting base 140 (described later), and is connected to the brake pedal (not shown) via the input rod 11. The first piston 121 includes a main body 121a extending along the axial direction and formed in a cylindrical shape, and a section at one end of the main body 121a (with the right side as a reference). Figure 2 The mounting portion 121b is formed by expanding radially from the right side (based on the reference point). The mounting portion 121b can be configured to be received within the first hole 111, and the outer diameter of the mounting portion 121b can be formed to be larger than the inner diameter of the secondary hole 142 of the mounting base 140 described later. This allows for the return of the first piston 121 (with...) Figure 2 When the brake pedal is moved to the left (based on the reference direction), the engagement part 121b is engaged with the mounting protrusion 141a of the mounting seat 140, thereby allowing it to be positioned in a certain position when the pedal force on the brake pedal is released. Furthermore, the first piston 121 is positioned on one side (with...) Figure 2 The right side (based on the reference) includes a mounting portion 121d recessed along the axial direction to stably connect the cover 127 and the elastic member 123 (described later), a hollow portion 121e extending from the mounting portion 121d, a connecting hole 121f extending radially through the hollow portion 121e and the connecting port 149a, and a stepped surface 121g formed between the mounting portion 121d and the hollow portion 121e, as the inner diameter of the mounting portion 121d is larger than the inner diameter of the hollow portion 121e. A gap flow path 100 is formed through the gap between the first piston 121 and the cover 127, which will be described in detail later.

[0097] The second piston 124 can be inserted into the second hole 112, allowing it to be displaced along the axial direction. The second piston 124 can be displaced via the first piston 121 and the elastic member 123 (described later). In the first hole 111, the space divided by the first piston 121 and the second piston 124 (described later) can form a first hydraulic chamber 122. In the second hole 112, the space divided by the inner wall and the second piston 124 can form a second hydraulic chamber 125. A return spring 126 can be provided in the second hydraulic chamber 125 to elastically support the second piston 124. Furthermore, a retractable elastic member 123 can be provided between the first piston 121 and the second piston 124. The elastic restoring force resulting from the compression of the elastic member 123 can provide the driver with a pedal feel. On the other side of the elastic member 123 (as shown below),... Figure 2 The left side (based on the reference) has a connecting protrusion 123a that is formed to engage with the cover 127 described later.

[0098] The support bracket 130 is fixed to the vehicle body, thereby supporting the hydraulic module 110 and the mounting base 140 (described later). The support bracket 130 may have a fastening portion 131 that engages with the mounting base 140 (described later) and a support portion 132 that is fixed to the vehicle body via a fixing plate 133. The fastening portion 131 and the mounting base 140 are connected to each other by multiple bolts 136, and the support portion 132 can be connected and fixed to the vehicle body. The support bracket 130 may be made of a metal material such as steel to ensure sufficient rigidity.

[0099] The mounting base 140 can be disposed between the hydraulic module 110 and the support bracket 130, so that the first piston 121 exposed outside the hydraulic module 110 can be inserted therein, and the hydraulic module 110 can be fixed and supported. The hydraulic module 110 may have one side (with... Figure 2 The right side (based on the reference) is combined with the other side (based on the reference) of the hydraulic module 110. Figure 2 The mounting portion 141 (based on the left side) and the mounting portion facing the other side (with Figure 2 An extension 143 extends from the left side (based on the reference) and penetrates the support bracket 130.

[0100] Furthermore, the mounting base 140 has a secondary hole 142 that extends and passes through it along the axial direction. The secondary hole 142 can be configured such that the first piston 121 can be inserted into and pass through it for displacement. At one end of the secondary hole 142 (with... Figure 2 The right end of the reference section 141 may be provided with a first stepped portion 142a formed in a stepped shape, on one side of the mounting portion 141 (with Figure 2The edge of one end of the secondary hole 142 in the right side (based on the reference) may be provided with a mounting protrusion 141a that protrudes in the axial direction. The mounting protrusion 141a is inserted into the first hole 111 of the hydraulic module 110, and the outer peripheral surface of the mounting protrusion 141a faces or contacts the inner peripheral surface of the first hole 111, thereby enabling simple installation and connection between the hydraulic module 110 and the mounting base 140.

[0101] A cover 146 may be provided at the other end of the extension 143 to prevent dust and other impurities from flowing into the secondary hole 142 and the interior of the hydraulic module 110. One end of the cover 146 may be supported by the extension 143 of the mounting base 140, and the other end may be supported by the support plate 147 fixed to the input rod 11, allowing it to extend and retract with the displacement of the input rod 11. Furthermore, a piston spring 148 may be supported at the other end of the extension 143, which elastically supports the input rod 11 to return the first piston 121. The piston spring 148 may be disposed inside the cover 146, and a noise-suppressing protrusion 144 may be provided between the cover 146 and the piston spring 148 to reduce noise and vibration caused by the movement of the piston spring 148. (See below) Figure 25 This will be explained in detail.

[0102] The secondary bore 142 may be provided with a connection port 149a for hydraulic communication with a reservoir containing pressurized medium. At least one oil seal 149b may be provided on one side and the other side of the connection port 149a to prevent leakage of the pressurized medium through the connection port 149a. The oil seal 149b may be housed in an oil seal groove recessed into the inner circumferential surface of the secondary bore 142. The connection port 129a may communicate with the first hydraulic chamber 122 via a gap flow path 100 described later (see reference below). Figures 4 to 7 This will be explained in detail.

[0103] The mounting base 140 may include a connecting flow path 145 that connects the secondary hole 142 and the hydraulic flow path 119 of the hydraulic module 110. The hydraulic flow path 119 of the hydraulic module 110 can be formed by offsetting a certain distance from the main holes 111 and 112, so that one end of the connecting flow path 145 is exposed on one side of the mounting portion 141 of the mounting base 140, while the other end is connected to the secondary hole 142 through a port 149a, etc., and can be formed by tilting at a certain angle relative to the axial direction. In order to achieve simple setup and assembly, according to the main cylinder 1 of this embodiment, after manufacturing the hydraulic module 110 and the mounting base 140 separately, the other side of the hydraulic module 110 and one side of the mounting base 140 are joined together. Therefore, it is necessary for the flow path of the hydraulic module 110 and the hole of the mounting base 140 to be connected to each other. Therefore, by forming the connecting flow path 145 by tilting the mounting base 140 at a predetermined angle relative to the axial direction, the flow of the pressurized medium can be maintained smoothly.

[0104] A cover 127 is provided between the first piston 121 and the elastic member 123. The cover 127 forms gap flow paths 100, 100 to remove residual pressure of the pressurized medium present in the first hydraulic chamber 122.

[0105] Figure 4 This is a cut perspective view showing the first piston 121 with the cover 127. And... Figure 5 This is a perspective view of cover 127. Figure 6 This is a cutaway perspective view of the first piston 121. Figure 7 It is shown in magnification Figure 2 The diagram for part A.

[0106] Reference Figures 4 to 7 The cover 127 can be clamped to one side of the first piston 121 (to... Figure 2 as well as Figure 7 The right side portion (based on the reference) and the other side portion of the elastic member 123 (with Figure 2 as well as Figure 7 Between the left side portion (based on the reference). The cover 127 includes a main body 127a that is inserted into the mounting portion 121d, and a side end of the main body 127a (with Figure 7 The flange portion 127b, which expands radially from the right end (based on the reference), and the connecting protrusion 123a of the elastic member 123 are inserted into the fastening hole 127c to achieve installation.

[0107] For a stable connection between the cover 127 and the first piston 121, the outer peripheral surface of the main body 127a and the inner peripheral surface of the mounting portion 121d can face or contact each other. The inner side of the main body 127a can be hollow to allow the elastic member 123 to easily enter. The main body 127a can be pressed onto the mounting portion 121d, but is not limited to this, and can be joined in various ways.

[0108] The gap flow path 100 includes: a first gap 101 formed by a recess along the axial direction on the outer peripheral surface of the main body 127a, and a gap at one end of the first piston 121 (with... Figure 2 as well as Figure 7 The second gap 102, which is formed by a radial recess on the other side of the flange portion 127b facing the reference right end, and is connected to the first gap 101; the third gap 103, which is formed by a radial recess on the stepped surface 121g of the first piston 121 and is connected to the second gap 102; and the fourth gap 104, which is formed by a recess on the stepped surface 121g of the first piston 121 in the edge direction and connects the adjacent third gaps 103 to each other.

[0109] With the second gap 102 formed on the flange portion 127b, the second gap 102 can achieve hydraulic communication with the first hydraulic chamber 122. Furthermore, the second gap 102 is connected to the first gap 101, the third gap 103, and the fourth gap 104, so the first hydraulic chamber 122 can achieve hydraulic communication with the connection port 149a through the hollow portion 121e and the connecting hole 121f. The connection port 149a is connected to a reservoir (not shown), thereby achieving hydraulic communication between the first hydraulic chamber 122 and the reservoir through the gap flow path 100.

[0110] The following describes the feature of removing residual pressure of the pressurized medium through cover 127 and gap flow path 100. When the braking system is switched to fallback mode due to an emergency such as a malfunction during normal operation, the hydraulic pressure of the pressurized medium supplied from the brake system's motor or pump (not shown) may be instantaneously transmitted to the first hydraulic chamber 122. Consequently, the hydraulic pressure inside the first hydraulic chamber 122 may not be released, leaving residual pressure. In this situation, it is difficult for the driver to carefully control the vehicle's braking, and it also affects the pedal force, potentially causing the driver to feel an unusual sensation.

[0111] Therefore, when residual pressure of the pressurized medium remains in the first hydraulic chamber 122, the residual pressure of the pressurized medium can be discharged to the reservoir through the gap flow path 100 formed by the gap between the first piston 121 and the cover 127. Specifically, the residual pressure in the first hydraulic chamber 122 can be transmitted sequentially through the second gap 102, the first gap 101, and the third gap 103 of the cover 127 to the hollow portion 121e inside the first piston 121. The pressurized medium flowing into the hollow portion 121e is discharged to the reservoir through the connecting hole 121f and the connection port 149a. This not only prevents dragging phenomena, but also maintains a constant stroke of the first piston.

[0112] The hydraulic module 110 and the mounting base 140 can be sandwiched between a first seal and second seals 116 and 117 to prevent leakage of the pressurized medium.

[0113] Figure 8 It is shown in magnification Figure 2 The diagram in part B, Figure 9 It is shown in magnification Figure 8 Refer to the diagram in part E. Figures 2 to 10 The first seal 116 can be clamped onto one side of the mounting base 140 (to... Figure 2 The right side (based on the reference) and the other side of the hydraulic module 110 (based on the reference) Figure 2Between the left side (as referenced), a sealing element is provided to seal the hydraulic flow path 119 of the hydraulic module 110 and the connecting flow path 145 of the mounting base 140. A first seal 116 extends along the periphery of the opening of the connecting flow path 145 on one side of the mounting base 140 or along the periphery of the opening of the hydraulic flow path 119 on the other side of the hydraulic module 110, thus forming a ring shape. Furthermore, the first seal 116 is inserted into and placed in a first receiving groove 113 recessed along the periphery of the opening of the hydraulic flow path 119 on the other side of the hydraulic module 110, thereby preventing the first seal 116 from dislodging even when a high-pressure pressurized medium is transmitted from the hydraulic flow path 119 or the connecting flow path 145.

[0114] The first seal 116 may have a central first main body portion 116a and a first blade portion 116b and a second blade portion 116c respectively provided on both sides of the first main body portion 116a, so as to effectively prevent leakage even when a pressurized medium with high pressure is transmitted from the hydraulic flow path 119 or the connecting flow path 145.

[0115] Figure 10 This is a diagram showing the deformation of the first seal 116 due to the hydraulic pressure of the pressurized medium, see reference. Figure 9 as well as Figure 10 The first seal 116 may include: a first main body portion 116a disposed in the center and constituting the main body, and an inner side of the first main body portion 116a adjacent to the hydraulic flow path 119 (to... Figure 9 as well as Figure 10 The first blade portion 116b, protruding from the upper side (based on the reference), is located on the outer side of the first main body portion 116a, offset from the hydraulic flow path 119. Figure 9 as well as Figure 10 The second blade portion 116c protrudes from the lower side (based on the reference). The inner peripheral surface of the first blade portion 116b and the outer peripheral surface of the second blade portion 116c, in other words, the portions facing the inner surface of the first receiving groove 113, can achieve surface contact with each other, so as to stably prevent leakage of the pressurized medium even when a pressurized medium with high pressure is transmitted. For this purpose, the inner peripheral surface of the first blade portion 116b and the outer peripheral surface of the second blade portion 116c can be formed into shapes corresponding to the inner surface of the first receiving groove 113. Thus, Figure 10 As shown, even when pressurized medium is transmitted from hydraulic flow path 119 or connecting flow path 145, the leakage of pressurized medium can be more effectively suppressed and prevented because the contact area between the outer peripheral surface of the second blade portion 116c and the inner surface of the first receiving groove 113 is enlarged.

[0116] Furthermore, in order to facilitate the deformation of the first blade portion 116b and the second blade portion 116c during the transmission of pressurized medium, the thickness of the first blade portion 116b or the second blade portion 116c (as shown in the figure) is [missing information]. Figure 9 The width (based on the left-right direction) can be made smaller than the thickness of the first main body 116a. Specifically, the first main body 116a can be formed into a circular shape with a cross-sectional shape that thickens towards the center, so as to maintain the state of contact between the two sides of the hydraulic module 110 and the mounting base 140 on the first receiving groove 113, and the thickness of the first blade portion 116b or the second blade portion 116c can be made smaller than the diameter of the first main body 116a. Thus, even if pressurized medium is transmitted from the hydraulic flow path 119 or the connecting flow path 145, the first main body 116a first seals the space between the hydraulic module 110 and the mounting base 140, and then the first blade portion 116b or the second blade portion 116c can easily deform, rapidly increasing the contact area with the first receiving groove 113, thereby stably preventing leakage of the pressurized medium.

[0117] Figure 11 This is a split perspective view showing the second seal 117 according to this embodiment. Figure 12 It is shown in magnification Figure 8 Refer to the diagram for part F. Figure 2 , Figure 11 as well as Figure 12 The second seal 117 can be clamped onto one side of the mounting base 140 (to... Figure 2 The right side (based on the reference) and the other side of the hydraulic module 110 (based on the reference) Figure 2 Between the left side (based on the reference), it is set to seal the main holes 111, 112 and shaft hole 118 of the hydraulic module 110.

[0118] The shaft hole 118 on the hydraulic module 110 can be offset from the main holes 111 and 112 by a certain distance, and can be configured to extend along the axial direction so that the shaft 20 (not shown) of the brake pedal displacement sensing device can be displaced. A connecting hole 118a can be formed between the main holes 111 and 112 and the shaft hole 118 along the axial direction, and a connecting component for connecting the first piston 121 and the shaft 20 is received in the connecting hole 118a (see reference). Figure 20 as well as Figure 19 ).

[0119] The second seal 117 can be formed on the other side of the hydraulic module 110, extending around the openings of the main holes 111 and 112 and the shaft hole 118. Furthermore, the second seal 117 can be inserted into and placed within the second receiving groove 114 recessed around the openings of the main holes 111 and 112 and the shaft hole 118 on the other side of the hydraulic module 110, thereby preventing the second seal 117 from detaching even when a high-pressure pressurized medium is transmitted from the main holes 111, 112, or the shaft hole 118.

[0120] The second seal 117 may have a central second main body portion 117a and a third blade portion 117b and a fourth blade portion 117c respectively provided on both sides of the second main body portion 117a, so as to effectively prevent leakage even when a high-pressure pressurized medium is transmitted from the hydraulic flow path 119 or the connecting flow path 145.

[0121] The second seal 117 may include: a second main body portion 117a disposed in the center and constituting the main body, and an inner side of the second main body portion 117a facing the main hole 111, 112 or the shaft hole 118 (to... Figure 12 The third blade portion 117b, protruding from the upper side (based on the reference), is located on the second main body portion 117a, on the outer side (alongside) away from the main holes 111, 112 or the shaft hole 118. Figure 12 The fourth blade portion 117c protrudes from the lower side (based on the reference). The inner peripheral surface of the third blade portion 117b and the outer peripheral surface of the fourth blade portion 117c, in other words, the portions facing the inner surface of the second receiving groove 114, can be in surface contact with the inner surface of the second receiving groove 114 to stably prevent leakage of the pressurized medium even when a high-pressure pressurized medium is being transmitted. For this purpose, the inner peripheral surface of the third blade portion 117b and the outer peripheral surface of the fourth blade portion 117c can be formed to correspond to the shape of the inner surface of the second receiving groove 114. Thus, with Figure 10 Similarly, the first seal 116 shown increases the contact area between the outer peripheral surface of the fourth blade portion 117c and the inner surface of the second receiving groove 114 even when pressurized medium is transmitted from the main bore 111, 112 or the shaft bore 118, thereby more effectively suppressing and preventing leakage of the pressurized medium.

[0122] Furthermore, in order to facilitate the deformation of the third blade portion 117b and the fourth blade portion 117c during the transmission of pressurized medium, the thickness of the third blade portion 117b or the fourth blade portion 117c (as shown in the figure) is... Figure 12The width in the left-right direction (based on the reference) can be made smaller than the thickness of the second main body 117a. Specifically, the second main body 117a can be formed into a circular shape with a cross-sectional shape that thickens towards the center, so as to maintain contact between the hydraulic module 110 and the mounting base 140 on both sides of the second receiving groove 114, and the thickness of the third blade portion 117b or the fourth blade portion 117c can be made smaller than the diameter of the second main body 117a. Thus, even if pressurized medium is transmitted from the main holes 111, 112 or the shaft hole 118, the second main body 117a first seals the space between the hydraulic module 110 and the mounting base 140, and then the third blade portion 117b or the fourth blade portion 117c can easily deform, rapidly increasing the contact area with the second receiving groove 114, thereby stably preventing leakage of the pressurized medium.

[0123] The bushing assembly is configured to guide the first piston 121 and the second piston 124 to move smoothly back and forth while preventing excessive friction and scratches between the piston and the bore.

[0124] Figure 13 as well as Figure 14 It is shown in magnification Figure 2 The diagram in part A, Figure 15 This is a perspective view showing the first bushing component 151. Figure 16 This is a perspective view showing the shock absorber component 152.

[0125] Reference Figure 2 , Figure 3 , Figures 13 to 16 The first bushing component 151 and one side of the first piston 121 (with Figure 2 , Figure 13 as well as Figure 14 Adjacent to the right side of the reference point, it is configured to guide the forward and backward movement of the first piston 121 to achieve stable sliding while preventing wear and damage caused by contact with the mounting base 140. One end of the secondary hole 142 (with...) Figure 13 as well as Figure 14 The right end portion (based on the reference) is provided with a first stepped portion 142a, the inner diameter of which is larger than the inner diameter of the secondary hole 142. The first bushing member 151 is formed in an annular shape, and its outer peripheral surface may abut against the inner peripheral surface of the first stepped portion 142a. The outer peripheral surface of the first bushing member 151 may be pressed against the inner peripheral surface of the first stepped portion 142a to stably support the first bushing member 151 on the first stepped portion 142a and prevent the first bushing member 151 from dislodging. The first bushing member 151 may be made of plastic material, and the diameter of the inner peripheral surface of the first bushing member 151 may be formed to correspond to the diameter of the outer peripheral surface of the main body 121a of the first piston 121.

[0126] Shock absorber component 152 is configured to return the first piston 121 (to) Figure 2 , Figure 13 as well as Figure 14 To prevent noise and vibration caused by impact between the first piston 121 and the mounting base 140 when moving to the left (based on the reference direction). The shock absorber component 152 can be coupled to one end of the outer circumferential surface of the first piston 121 (to prevent noise and vibration caused by impact between the first piston 121 and the mounting base 140). Figure 13 as well as Figure 14 The shock absorber component 152 is positioned adjacent to the right end of the first piston 121 (based on the reference point) and can be made of an elastically deformable material to mitigate the impact from the contact between the first piston 121 and the mounting base 140. The shock absorber component 152 can be inserted into and closely fitted into a circumferentially recessed groove on the outer circumferential surface of the first piston 121, so that the shock absorber component 152 can be stably supported on the first piston 121 while preventing detachment. Furthermore, the shock absorber component 152 can be positioned on one side (with the reference point being the right end of the first piston 121). Figure 13 as well as Figure 14 The right side (based on the reference) is supported by the mounting portion 121b of the first piston 121, and the other side (with) Figure 13 as well as Figure 14 The left side (as referenced) can face and contact the first bushing component 151, and the shock absorber component 152 can enter the inner side of the first step portion 142a as the first piston 121 moves back and forth. The shock absorber component 152 may be provided with an outer groove portion 152a recessed on at least one of the two sides to facilitate easy and rapid compression and recovery.

[0127] The second bushing component 160 is designed to guide the reciprocating movement of the second piston 124 while preventing wear and damage caused by contact with the hydraulic module 110.

[0128] Figure 17 It is shown in magnification Figure 2 The diagram of part C, Figure 18 This is a perspective view showing the second bushing component 160.

[0129] Reference Figure 2 , Figure 3 , Figure 17 as well as Figure 18 The second bushing component 160 may be disposed between the second piston 124 and the second hole 112. The other end of the second hole 112 (to...) Figure 17The left end (based on the reference) has a second stepped portion 112a with an inner diameter larger than that of the second hole 112. The second bushing member 160 is formed in an annular shape, and its outer peripheral surface can abut against the inner peripheral surface of the second stepped portion 112a. The outer peripheral surface of the second bushing member 160 can press against the inner peripheral surface of the second stepped portion 112a to stably support the second bushing member 160 on the second stepped portion 112a and prevent the second bushing member 160 from dislodging. The second bushing member 160 can be made of plastic, and the diameter of the inner peripheral surface of the second bushing member 160 can be formed to correspond to the diameter of the outer peripheral surface of the second piston 124. Furthermore, the second bushing member 160 may include an inner groove 160a formed in the circumferential direction on the inner peripheral surface to facilitate the sliding of the second piston 124. By reducing the direct friction between the second piston 124 and the hydraulic module 110 through the second bushing member 160, scratches and damage can be prevented, thereby improving product durability.

[0130] The third bushing component 170 is on the other side of the first piston 121 (with) Figure 2 The first piston 121 is positioned adjacent to the left side of the mounting base 140 to guide its reciprocating movement, while also preventing wear and damage from contact with the mounting base 140.

[0131] Figure 19 This is a perspective view showing the third bushing component 170, with reference to... Figure 2 as well as Figure 19 At the other end of the secondary hole 142 (with Figure 2 The left end portion (based on the reference) has a third stepped portion 142b with an inner diameter larger than that of the secondary hole 142. A third bushing member 170 can be inserted into the third stepped portion 142b. Similar to the first bushing member 151, the third bushing member 170 is formed in an annular shape, and its outer peripheral surface can abut against the inner peripheral surface of the third stepped portion 142b. The outer peripheral surface of the third bushing member 170 can be pressed against the inner peripheral surface of the third stepped portion 142b to stably support the third bushing member 170 on the third stepped portion 142b and prevent the third bushing member 170 from dislodging. The third bushing member 170 can be made of plastic, and the diameter of the inner peripheral surface of the third bushing member 170 can be formed to correspond to the diameter of the outer peripheral surface of the main body 121a of the first piston 121.

[0132] Figure 20 This is a cutaway perspective view of the hydraulic module 110. Figure 21 This is a side cross-sectional view of the main cylinder 1, showing the state in which the mounting platform 181 is supported by the first limiter 182. Figure 22 It is shown in magnification Figure 21 The diagram for part G. And, Figure 23This is a cross-sectional view showing the main holes 111, 112, shaft hole 118, and connecting hole 118a in other directions. Figure 24 This is a cross-sectional view from another direction showing the mounting platform 181 being supported by the first limiter 182.

[0133] Reference Figures 20 to 24 The hydraulic module 110 includes: a shaft hole 118 for axial movement of the shaft 20 of a displacement sensing device (not shown) that senses pedal displacement; and a connecting hole 118a connecting the main holes 111 and 112 and the shaft hole 118. A magnet is supported on the shaft 20, or the shaft 20 is composed of a magnet, so that a sensor on the displacement sensing device senses changes in the magnetic force or magnetic flux density of the magnet, thereby sensing the displacement of the first piston 121. Furthermore, the shaft 20 and the first piston 121 can be connected and engaged by a fastening member 30, which can move along the connecting hole 118a. This configuration, where the main holes 111 and 112, which move the first piston and the second piston 124 inside the hydraulic module 110, and the shaft hole 118, which moves the shaft 20, are interconnected through the connecting hole 118a, thereby eliminating the need for additional sealing components to seal each hole, reducing the number of components, and simplifying the structure. Furthermore, the main holes 111, 112 and shaft hole 118 can be configured close to each other, thus enabling the miniaturization and weight reduction of the hydraulic module 110.

[0134] A mounting platform 181, which expands or protrudes radially, may be provided on the outer peripheral surface of the second piston 124. A first limiter 182, which engages with and supports the mounting platform 181, may be provided on the inner peripheral surfaces of the main holes 111 and 112. The outer diameter of the mounting platform 181 is larger than the inner diameter of the first limiter 182, so that the mounting platform 181 can engage with the first limiter 182. Specifically, the other end of the mounting platform 181 (with...) Figure 21 and the left end based on 18) and one side end of the first limiter 182 (with Figure 21 And the right end (based on 18) contacts, thereby limiting the movement distance of the second piston 124 in the return direction, so as to maintain the working stroke evenly, and thus the second piston 124 can be positioned in a certain position when the pedal force on the brake pedal is released.

[0135] The first limiter 182 is mounted on the inner circumferential surface of the main holes 111 and 112, and can expand or protrude inward toward the main holes 111 and 112 to hook and support the mounting platform 181. The first limiter 182 may have an annular opening 182a with one open side, and the connecting hole 118a may be located inside the opening 182a. Thus, even if the piston and fastening member 30 move, interference with the first limiter 182 can be prevented. The first limiter 182 is made of plastic material, which can suppress noise and vibration generated during contact and impact with the mounting platform 181. Furthermore, the diameter of the inner circumferential surface of the first limiter 182 is formed to correspond to the diameter of the outer circumferential surface of the portion facing the second piston 124, thereby preventing sagging due to the weight of the second piston 124.

[0136] To stably support and install the first limiter 182 on the main holes 111 and 112, specifically the inner circumferential surface of the main holes 111 and 112, and more specifically the first hole 111, may be provided with a first limiting groove 183 formed in a circumferential direction. The first limiter 182 is inserted into and placed in the first limiting groove 183, thereby being stably supported in a certain position and preventing disengagement. The first limiting groove 183 may include an anti-disengagement part 184 protruding inward toward the opening 182a and facing both ends of the opening 182a of the first limiter 182. The anti-disengagement part 184 prevents the rotation of the first limiter 182, thereby preventing the first limiter 182 from entering the connecting hole 118a side. Furthermore, the inner circumferential surface of the anti-disengagement part 184 may be formed to be continuous with the inner circumferential surface of the main holes 111 and 112 or the first hole 111, to prevent the piston from being interfered with by the anti-disengagement part 184. Figure 22 as well as Figure 23 The illustration shows an example in which the two ends of the anti-detachment portion 184 are formed into a curved shape by grinding in order to facilitate the manufacturing of the anti-detachment portion 184 on the hydraulic module 110. However, this is only one example to help understand the invention and is not limited to this shape. Depending on the manufacturing method, the shape of the two ends of the anti-detachment portion 184 can be formed in a variety of ways.

[0137] Figure 25 It is shown in magnification Figure 2 The diagram for part D.

[0138] Reference Figure 25 The support plate 147 can be fixedly mounted on the input rod 11. The support plate 147 can support a cover 146 that extends and retracts with the displacement of the input rod 11, and can also support the other end of a piston spring 148 that elastically supports the input rod 11 and the first piston 121. The support plate 147 can be plate-shaped and fixed to the outer peripheral surface of the input rod 11 to firmly support the cover 146 and the piston spring 148. The cover 146 can be made of a material such as elastically deformable rubber.

[0139] On the other hand, the input rod 11 and the first piston 121 reciprocate due to the operation of the brake pedal. This reciprocating movement of the input rod 11 causes the cover 146 to extend and retract. For the cover 146 to deform smoothly, its interior needs to be connected to the outside. If dust or moisture flows into the cover 146, it could adversely affect the performance of components such as the input rod 11 and the piston spring 148. Furthermore, the possibility of impurities flowing into the mounting base 140 or the hydraulic module 110 increases, potentially reducing the product's performance and durability.

[0140] For this purpose, the support plate 147 includes at least one vent 147a that extends through the interior and exterior of the cover 146, and the vent 147a can be formed at a certain angle relative to the axial direction. The interior and exterior of the cover 146 are connected through the vent 147a, thereby enabling the cover 146 to deform smoothly. At the same time, the vent 147a is formed at a predetermined angle to prevent dust and other impurities from directly intruding into the interior of the cover 146, thereby suppressing the inflow of impurities.

[0141] On the other hand, after the input rod 11 and the first piston 121 have moved forward due to the operation of the brake pedal, and the pedal force of the brake pedal is released or the brake is released, the input rod 11 and the first piston 121 return to their original positions via the piston spring 148. At this time, the piston spring 148 is compressed and then expands again, and the elastic restoring force of the piston spring 148 itself causes vibration and noise.

[0142] Therefore, according to the master cylinder 1 of this embodiment, in order to reduce the noise and vibration generated during the operation of the piston spring 148, a noise suppression protrusion 144 is provided.

[0143] Figure 26 This is a side view showing the second limiter 190 in other directions. Figure 27 yes Figure 25 The cross-sectional view along the A-A' direction is a side view in another direction showing the state in which the first piston 121 is equipped with the second limiter 190.

[0144] Reference Figures 25 to 27The noise-suppressing protrusion 144 can be provided on the inner peripheral surface of the cover 146. The noise-suppressing protrusion 144 is formed protruding inward from the inner peripheral surface of the cover 146, thereby maintaining contact with at least a portion of the outer peripheral surface of the piston spring 148. The noise-suppressing protrusion 144 can be integrally formed with the cover 146, and thus, like the cover 146, the noise-suppressing protrusion 144 can be made of a material such as elastically deformable rubber. The noise-suppressing protrusion 144 protrudes inward or extends from the inner peripheral surface of the cover 146 and contacts at least one location on the outer peripheral surface of the piston spring 148, thereby absorbing the echo generated by the piston spring 148 and mitigating noise and vibration. The noise-suppressing protrusion 144 and at least one location on the outer peripheral surface of the piston spring 148 can be configured to maintain constant contact regardless of whether the piston spring 148 is compressed or expanded.

[0145] The second limiter 190 can be located on the other side of the first piston 121 exposed to the outside of the mounting base 140 (to... Figure 25 On the outer peripheral surface of the first piston 121 (with the left side as the reference). The second limiter 190 can be installed by expanding or protruding radially from the outer peripheral surface of the first piston 121. The second limiter 190 is formed in a ring shape and has a receiving part for the passage of the first piston 121 on the inner side and a mounting opening 195 formed on the open side. Thus, as the brake pedal is operated and the first piston 121 moves forward, the second limiter 190 is engaged with the other end of the mounting base 140 (with the left side as the reference). Figure 25 The left end is used as a reference, thereby limiting the forward movement distance of the first piston 121, thus enabling the working stroke to be maintained evenly. The second limiter 190 can be inserted into and placed in the second limiting groove 121c formed by the circumferential recess on the outer peripheral surface of the first piston 121, so as to be stably supported on the outer peripheral surface of the first piston 121.

[0146] On the other hand, noise and vibration may occur when the second limiter 190 contacts the other end of the mounting base 140. To reduce the noise and vibration that occur at this time, the receiving portion of the second limiter 190 can be divided into two parts with different diameters. Specifically, the receiving portion can be divided into a first receiving portion 191 with a first radius d1 based on a first center 191a and a second receiving portion 192 with a second radius d2 based on a second center 192a. Compared with the first center 191a, the second center 192a is centrifugally oriented towards the mounting opening 195, and the second radius d2 can be formed to be smaller than the first radius d1. Thus, when the second limiter 190 is mounted on the outer peripheral surface of the first piston 121, the inner peripheral surface of the second limiter 190 and the outer peripheral surface of the first piston 121 are engaged with each other through three contact points 193. The second limiter 190 and the first piston 121 are connected to each other through three contact points 193, thereby achieving a fastening force between the two component elements and minimizing the contact area. This allows noise and vibration to be suppressed even if the second limiter 190 contacts the mounting base 140 and causes shaking on the outer circumference of the first piston 121.

Claims

1. A master cylinder comprising: a hydraulic module having a main hole formed in an axial direction inside; a first piston inserted into the main hole on one side to be displaceable and exposed to the outside of the hydraulic module on the other side, the first piston being mechanically connected to a brake pedal by an input rod, one end of the input rod being connected to the first piston and the other end being connected to the brake pedal; a second piston inserted into the main hole inside the first piston to be displaceable; a resilient member between the first piston and the second piston for providing pedal feel; and a mounting base having a sub-hole formed in an axial direction inside, the first piston being inserted into and passing through the sub-hole to be displaceable, one side surface of the mounting base being combined with the other side surface of the hydraulic module, wherein the hydraulic module includes at least one hydraulic flow path passing through the other side surface, the mounting base includes a connection flow path communicating the sub-hole and the hydraulic flow path.

2. The master cylinder according to claim 1, wherein the hydraulic flow path is formed at a distance from the main hole on the hydraulic module, one end of the connection flow path is exposed on one side surface of the mounting base and the other end is connected to the sub-hole, and is formed to be inclined at an angle with respect to the axial direction. including:

3. The master cylinder according to claim 2, wherein a support plate fixed to the input rod; and a cover having one end supported by the mounting base and the other end supported by the support plate to be extendable and retractable, wherein the support plate includes a vent hole formed to pass through in a manner of communicating the inside and the outside of the cover, the vent hole is formed to be inclined at an angle with respect to the axial direction. further including: a first seal member sandwiched between the one side surface of the mounting base and the other side surface of the hydraulic module to seal the hydraulic flow path and the connection flow path, 4. The master cylinder according to claim 2, wherein the first seal member is formed to extend along an opening periphery of the connection flow path on the one side surface of the mounting base or to extend along an opening periphery of the hydraulic flow path on the other side surface of the hydraulic module.

5. The master cylinder according to claim 4, wherein the first seal member is formed in a ring shape.

6. The master cylinder according to claim 5, wherein the first seal member is inserted into and seated in a first housing groove recessed in the other side surface of the hydraulic module.

7. The master cylinder according to claim 6, wherein the first seal member includes: a central first body portion; a first blade portion protruding from the first body portion toward an inside adjacent to the hydraulic flow path; and a second blade portion protruding from the first body portion toward an outside deviated from the hydraulic flow path.

8. The master cylinder according to claim 7, wherein an outer peripheral surface of the second blade portion is formed to correspond to a shape of an inner surface of the first housing groove.

9. The master cylinder according to claim 8, wherein a cross-sectional shape of the first body portion is formed in a circular shape, and a thickness of the second blade portion is formed to be smaller than a diameter of the first body portion.

10. The master cylinder according to claim 2, wherein the hydraulic module further includes a shaft hole formed in an axial direction inside. ​ ​ The master cylinder described above further includes: a second seal member interposed between one side surface of the mounting base and the other side surface of the hydraulic module to seal the main bore and the shaft bore, the second seal member extending along the periphery of the opening of the main bore and the opening of the shaft bore on the other side surface of the hydraulic module.

11. The master cylinder according to claim 10, wherein the second seal member is inserted and seated in a second housing groove recessed in the other side surface of the hydraulic module.

12. The master cylinder according to claim 11, wherein the second seal member includes: a central second body portion; a third blade portion protruding from the second body portion toward an inner side adjacent to the main bore or the shaft bore; and a fourth blade portion protruding from the second body portion toward an outer side away from the main bore or the shaft bore.

13. The master cylinder according to claim 12, wherein an outer peripheral surface of the fourth blade portion is formed to correspond to the shape of an inner surface of the second housing groove, a cross-sectional shape of the second body portion is circular, a thickness of the fourth blade portion is smaller than a diameter of the second body portion.

14. The master cylinder according to claim 2, wherein the sub bore further includes a first step portion formed in a stepped manner at one end portion, the master cylinder further includes: a damper member of which at least a portion is able to enter an inner side of the first step portion, the damper member includes a plurality of outer side groove portions recessed in at least either one of one side surface and the other side surface.

15. The master cylinder according to claim 10, wherein the hydraulic module further includes a communication bore communicating the main bore and the shaft bore, the second piston includes a hooking platform protruding from an outer peripheral surface, the master cylinder further includes: a first limiter supported by the hooking platform being hooked at an inner peripheral surface of the main bore and provided with an opening portion open at one side, the communication bore is located inside the opening portion.

16. The master cylinder according to claim 15, wherein the main bore further includes a first limiting groove recessed in a circumferential direction at an inner peripheral surface, at least a portion of the first limiter is inserted and seated in the first limiting groove.

17. The master cylinder according to claim 16, wherein the first limiting groove includes an anti-disengagement portion protruding from an inner side of the opening portion.

18. The master cylinder of claim 2 wherein, includes: an input rod having one end connected to the first piston and the other end connected to the brake pedal; a support plate fixed to the input rod; a cover supported at one end by the mounting base and at the other end by the support plate and capable of being extended and contracted; and a piston spring having one end supported by the mounting base and the other end supported by the support plate to elastically support the input rod or the first piston, a noise suppression protrusion protruding toward an inner side is provided at an inner peripheral surface of the cover so as to maintain contact with at least a portion of an outer peripheral surface of the piston spring.

19. The master cylinder of claim 18, wherein, further includes: a second limiter provided at a position exposed to an outside of the mounting base on an outer peripheral surface of the first piston, the second limiter includes: a housing portion located at an inner side and through which the first piston passes; and an installation opening open to one side.

20. The master cylinder according to claim 19, wherein An outer circumferential surface of the first piston is formed in a cylindrical shape, The housing portion includes a first center, a first housing portion having a first radius from the first center, a second center, and a second housing portion having a second radius from the second center, The second center is formed closer to the installation opening than the first center, The second radius is formed smaller than the first radius.

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