Pedal simulator and vehicle braking device with this

Abstract

Pedal simulator, comprehensive: a damper housing unit; a damper mounting unit coupled to the damper housing unit; a first bearing unit which is rotatably arranged on the damper mounting unit; a damper piston unit that is slidably mounted within the damper housing unit; a damper unit coupled to the damper piston unit, which is housed within the damper housing unit and is compressed by a movement of the damper piston unit; a damper pressure unit coupled to the damper piston unit to compress the damper piston unit; and a first elastic unit that is arranged between the damper pressure unit and the damper housing unit to elastically support the damper pressure unit.

Description

Background area

[0001] Example embodiments of the present disclosure relate to a pedal simulator and a vehicle braking device including the same, and more particularly to a pedal simulator capable of implementing regenerative braking and a vehicle braking device including the same. Description of the relevant state of the art

[0002] An electric vehicle braking system is a braking system that generates braking force using an electrically controlled electric brake caliper without a mechanical connection. Electric braking systems, commonly used in electric vehicles, utilize regenerative braking.

[0003] In the related art, in order to implement regenerative braking in an electric braking system, a separate independent chamber such as a valve is provided to prevent a pedal force from being transmitted to a power generated by a motor, so that a sense of difference of a pedal treading force in a regenerative braking section is cancelled, thereby achieving structural separation.

[0004] In electric vehicles, regenerative braking force is generated when an accelerator pedal is released during driving. There is a problem that a large difference in the pedal operation force associated with regenerative braking is felt in the initial phase of a brake pedal operation. Therefore, it is necessary to solve this problem.

[0005] The background of the present disclosure is disclosed in Korean Patent No. 10-2372394 (issued on March 11, 2022 and entitled “Braking Device for Vehicle”). Overview

[0006] The present disclosure has been made to solve the above-mentioned problems, and an object of the present disclosure is to provide a pedal simulator capable of improving regenerative braking performance and implementing pedal feel, and a vehicle braking device including the same.

[0007] Another object of the present disclosure is to provide a pedal simulator capable of improving a feeling of the difference in a pedal operating force during regenerative braking, and a vehicle braking device including the same.

[0008] To solve the above problems, a pedal simulator according to the present disclosure includes: a damper housing unit; a damper holder unit coupled to the damper housing unit; a first bearing unit rotatably disposed on the damper holder unit; a damper piston unit slidably received within the damper housing unit; a damper unit coupled to the damper piston unit, received within the damper housing unit, and compressed by movement of the damper piston unit; a damper pressure unit coupled to the damper piston unit to compress the damper piston unit; and a first elastic unit disposed between the damper pressure unit and the damper housing unit to elastically support the damper pressure unit.

[0009] The damper housing unit may include: a damper housing body having a side to which the damper holding unit is coupled, wherein the damper piston unit and the damper unit are arranged in the damper housing body; and a seating portion protruding from an inner peripheral surface of the damper housing body and extending along a circumferential direction of the damper housing body, wherein the damper piston unit is seated on the seating portion by an elastic force of the first elastic unit.

[0010] The seating area may include one or more step areas recessed into an outer surface of the seating area in contact with the damper piston unit.

[0011] The step area can be arranged along a circumferential direction of the seating area.

[0012] The one or more step portions may comprise a plurality of step portions spaced apart from one another along the circumferential direction of the seating portion.

[0013] Each of the step areas may extend radially from a central area of ​​the seating area.

[0014] Each of the step areas can have the shape of a polygon or a semicircle in cross-section.

[0015] The damper holder unit may include: a holder body coupled to the damper housing unit and to which the first bearing unit is rotatably coupled; and a holder projection protruding from an outer surface of the holder body.

[0016] The damper pressure unit may include: a push rod portion rotatably coupled to the damper piston unit; and a first seat portion axially coupled to the push rod portion, wherein the first elastic unit is seated on the first seat portion.

[0017] A vehicle brake device according to the present disclosure includes: a housing unit; a gear unit rotatably disposed in the housing unit and rotated by the action of a rotational force of an engine; a motion conversion unit disposed within the housing unit and coupled to the gear unit to convert a rotational motion of the gear unit into a linear motion; a second elastic unit configured to elastically support the motion conversion unit within the housing unit; a piston unit movably coupled to the motion conversion unit; a master cylinder unit coupled to one side of the housing unit and configured to generate hydraulic pressure by inserting the piston unit; a second bearing unit disposed within the housing unit to rotatably support the gear unit;and the pedal simulator, which is movably arranged on the other side of the housing unit and coupled to the motion conversion unit;

[0018] The motion conversion unit may include: a bolt part slidably coupled to the gear unit and rotated together with the gear unit; and a nut part coupled to the bolt part and moved along the bolt part.

[0019] The piston unit can be coupled to the nut part and moved together with the nut part.

[0020] The second elastic unit can elastically support the female part.

[0021] The nut member may include: a nut body spirally coupled to the bolt member; a second seat portion protruding from an outer peripheral surface of the nut body, the second elastic unit being seated on the second seat portion; and a rotation preventing portion disposed on the nut body to restrict rotation of the nut body.

[0022] The rotation preventing portion may include a projection protruding from an outer peripheral surface of the second seating portion and contacting an inner surface of the housing unit.

[0023] The screw bolt part may include: a screw body axially coupled to an inner side of the gear unit, the screw body being slidably movable and having a hollow prism shape; and a screw shaft disposed at one end of the screw body and spirally coupled to the nut body, the screw body being linearly moved along the screw shaft.

[0024] The present disclosure has the effect of improving the regenerative braking performance and increasing the amount of regenerative braking.

[0025] Furthermore, the present disclosure has the effect of minimizing the addition of parts and implementing a pedal feel without increasing a structure.

[0026] Furthermore, the present disclosure has the effect of improving the feeling of the difference in pedal operating force during regenerative braking. Short description of the drawings Fig. 1 is a cross-sectional view illustrating a vehicle brake device according to the embodiment of the present disclosure. Fig. 2 is a perspective view illustrating a motion conversion unit in the vehicle brake device according to the embodiment of the present disclosure. Fig. 3 is a perspective view of the motion conversion unit in Fig. 2 seen in a different direction. Fig. 4 is a perspective view illustrating a pedal simulator according to the embodiment of the present disclosure. Fig. 5 is an exploded perspective view and a partially enlarged plan view of Fig. 4. Fig. 6 to 8 are cross-sectional views along the line AA in Fig. 5. Fig. 9 is a cross-sectional view illustrating an operating state of the vehicle brake device according to the embodiment of the present disclosure. Detailed description

[0027] Hereinafter, a pedal simulator and a vehicle brake device incorporating the same according to the present disclosure will be described with reference to the accompanying drawings. Incidentally, the thicknesses of lines or the sizes of elements illustrated in the drawings may be exaggerated for the sake of clarity and ease of explanation. Furthermore, terms described below are defined in consideration of their functions in the present disclosure and may be changed depending on the intention of a user or operator or practice. Accordingly, such terms should be defined based on the disclosure of the present specification.

[0028] Fig. 1 is a cross-sectional view illustrating a vehicle brake device according to the embodiment of the present disclosure, Fig. 2 is a perspective view illustrating a motion conversion unit in the vehicle braking device according to the embodiment of the present disclosure, and Fig. 3 is a perspective view of the motion conversion unit in Fig. 2 when viewed from a different direction.

[0029] With reference to the Fig. 1 to 3, a vehicle brake device 1 according to the embodiment of the present disclosure includes a housing unit 100, a gear unit 200, a motion conversion unit 300, a second elastic unit 400, a piston unit 500, a master cylinder unit 600, a second bearing unit 700, and a pedal simulator 800, which will be described in detail as follows.

[0030] The housing unit 100 may be formed in a hollow shape having an interior space, and a motor 10 may be provided on the outside of the housing unit 100.

[0031] The gear unit 200 can be rotatably arranged within the housing unit 100. The gear unit 200 can be located within the housing unit 100 or can be arranged on one side of the housing unit 100 and rotatably coupled to the housing unit 100.

[0032] The gear unit 200 may be connected to the motor 10 located on the outside of the housing unit 100 and may be rotated by the action of the rotational force of the motor 10. The gear unit 200 may be hollow, with a central region penetrated.

[0033] The motion conversion unit 300 may be installed within the housing unit 100 and coupled to the gear unit 200. The motion conversion unit 300 converts the rotational motion of the gear unit 200 into a linear motion and may include a bolt part 310 and a nut part 320.

[0034] In one embodiment of the motion conversion unit 300, the screw bolt part 310 may be coupled to the gear unit 200 and rotated together with the gear unit 200, and the nut part 320 may be coupled to the screw bolt part 310 and moved linearly along the screw bolt part 310.

[0035] In another embodiment of the motion conversion unit 300, the nut member 320 may be coupled to the gear unit 200 and rotated together with the gear unit 200, and the screw bolt member 310 coupled to the nut member 320 may be moved linearly in an axial direction by rotating the nut member 320. In such a case, the piston unit 500 to be described below may be coupled to the linearly moving screw bolt member 310.

[0036] The following describes an embodiment in which, in the motion conversion unit 300 of the vehicle brake device 1 according to the present disclosure, the nut part 320 coupled to the bolt part 310 is moved linearly along the bolt part 310.

[0037] The screw bolt part 310 can be installed inside the housing unit 100. The screw bolt part 310 can be movably received in the housing unit 100. The screw bolt part 310 can be arranged in a longitudinal direction of the housing unit 100.

[0038] The screw bolt part 310 may be slidably coupled to the gear unit 200. Additionally, the screw bolt part 310 may penetrate the center of the gear unit 200 to be slidably coupled to the inside of the gear unit 200, and may reciprocate linearly in the longitudinal direction of the housing unit 100.

[0039] The screw bolt part 310 can rotate together with the gear unit 200 in the same direction as the rotation direction of the gear unit 200. The screw bolt part 310 can include a screw body 311 and a screw shaft 312.

[0040] The bolt body 311 can be axially coupled to the gear unit 200 by penetrating the center of the gear unit 200, and it can be slidably moved within the gear unit 200. The bolt body 311 can be formed in a prism shape. Additionally, the cross section of the bolt body 311 can be formed in a polygonal shape with angled corners.

[0041] An inner diameter of the gear unit 200 may be formed to be equal to the outer diameter of the screw body 311, so that the rotating gear unit 200 and the screw body 311 are engaged with each other. The bolt body 311 may be hollow and open at one end.

[0042] A damper holder unit 820 of the pedal simulator 800 to be described below can be inserted into the screw body 311 so that the damper holder unit 820 can be received in the screw body 311.

[0043] The screw shaft 312 may be arranged at one end of the screw body 311. The screw shaft 312 may be provided integrally with the bolt body 311. The screw shaft 312 and the bolt body 311 may be arranged on the same axial line. The screw shaft 312 may rotate axially in the same direction as the rotation direction of the screw body 311, which is rotated by the rotation of the gear 200.

[0044] Threads may be formed on an outer surface of the screw shaft 312 along its outer diameter. The nut member 320 may be spirally coupled to the screw shaft 312, and the nut member 320 may reciprocate linearly in the axial direction of the screw shaft 312 according to the rotational direction of the screw shaft 312.

[0045] The nut member 320 may be coupled to the bolt member 310 and may be moved along the bolt member 310. The nut member 320 may include a nut body 321, a second seating portion 322, and an anti-rotation portion 323.

[0046] The nut body 321 may be spirally coupled to the screw shaft 312. Threads may be formed on an inner surface of the nut body 321 along its inner diameter.

[0047] The second seating portion 322 may protrude from an outer peripheral surface of the nut body 321. The second seating portion 322 may be formed along a circumferential direction of the nut body 321. The second elastic unit 400, which will be described below, may be seated on the second seating portion 322 in a state where one side of the second elastic unit 400 is in contact with an outer surface of the second seating portion 322. In addition, one side of the second elastic unit 400 may be supported by the second seating portion 322.

[0048] The rotation-preventing portion 323 may be provided on the second seat portion 322. The rotation-preventing portion 323 may restrict the rotation of the nut body 321 so that the nut body 321, which is moved along the screw axis 312, does not rotate along with the screw axis 312. The rotation-preventing portion 323 may include a protrusion 323a.

[0049] The projection 323a may protrude from an outer peripheral surface of the second seating portion 322. A plurality of projections 323a may be arranged to be spaced apart from each other along a circumferential direction of the second seating portion 322. The projections 323a may contact the inner surface of the housing unit 100. In addition, the housing unit 100 may include a guide member (not shown) that guides the linear movement of the nut member 320.

[0050] The guide member may be recessed into the inner surface of the housing unit 100. The guide member may be formed in the longitudinal direction of the housing unit 100. The projection 323a is located within the guide member and moves along the guide member, allowing the nut body 321 to move linearly without being rotated.

[0051] The second elastic unit 400 can elastically support the motion conversion unit 300 within the housing unit 100. Additionally, the second elastic unit 400 can elastically support the nut member 320. The second elastic unit 400 can be in contact with the inner surface of the housing member 100 on one side and with an outer surface of the nut member 320 on the other side, and can provide an elastic force to the bolt member 310 to which the nut member 320 is coupled.

[0052] The second elastic unit 400 can be compressed by the nut part 320, which is moved linearly along the screw axis 312, or it can be compressed by the screw bolt part 310, which slides on the gear unit 200 and moves linearly thereon.

[0053] The compressed second elastic unit 400 can provide an elastic force (elastic restoring force) to the bolt portion 310 to return the bolt portion 310 to its original position. The second elastic unit 400 can include a coil spring surrounding the outside of the piston unit 500.

[0054] The piston unit 500 may be coupled to the nut part 320. Additionally, a rod-shaped portion of the piston unit 500 may be coupled to surround the outside of the nut body 321. The piston unit 500 may move linearly together with the nut part 320 in cooperation with the nut part 320.

[0055] A head portion of the piston unit 500 can be inserted into the master cylinder unit 600 described below, which is provided on one side of the housing unit 100.

[0056] The master cylinder unit 600 may be coupled to one side of the housing unit 100. In another embodiment, the master cylinder unit 600 may be provided integrally with the housing unit 100. The master cylinder unit 600 may be formed as a hollow body.

[0057] An interior of the housing unit 100 and an interior of the master cylinder unit 600 can communicate with each other. The piston unit 500 can be inserted into the master cylinder unit 600. The master cylinder unit 600 can generate hydraulic braking pressure by pressing the piston unit 500.

[0058] The second bearing unit 700 can be installed within the housing unit 100 to rotatably support the gear unit 200. An outer ring of the second bearing unit 700 can be in contact with the inner surface of the housing unit 100, and an inner ring thereof can be in contact with an outer surface of the gear unit 200.

[0059] Fig. 4 is a perspective view illustrating the pedal simulator according to the embodiment of the present disclosure, Fig. 5 is an exploded perspective view and a partially enlarged plan view of Fig. 4, and Fig. 6 to 8 are cross-sectional views taken along the line AA in Fig. 5.

[0060] With reference to the Fig. 1 to 8, the pedal simulator 800 according to the embodiment of the present disclosure may be slidably disposed on the other side of the housing unit 100. The screw bolt part 310 may be rotatably coupled to the pedal simulator 800.

[0061] The pedal simulator 800 may include a damper housing unit 810, the damper holder unit 820, a first bearing unit 830, a damper piston unit 840, a damper unit 850, a damper pressure unit 860, and a first elastic unit 870.

[0062] The damper housing unit 810 may be slidably mounted on the housing unit 100. The damper housing unit 810 may have a hollow shape and may be formed in a shape with both sides open.

[0063] The interior of the damper housing unit 810 may be filled with a lubricant, such as grease or brake fluid. The damper housing unit 810 may include a damper housing body 811 and a seating area 812.

[0064] The damper housing body 811 has one side (left side in Fig. 2) to which the damper holder unit 820 to be described below is coupled, and can accommodate the damper piston unit 840 and the damper unit 850 to be described below therein.

[0065] The seating portion 812 may be provided on the other side of the damper housing body 811 and protrude from an inner peripheral surface of the damper housing body 811. The seating portion 812 may be formed along a circumferential direction of the damper housing body 811. The seating portion 812 may be formed in a hollow shape with a central portion penetrated.

[0066] The damper piston unit 840 can be seated on the seating portion 812 by an elastic force (elastic restoring force) of the first elastic unit 870, which will be described below.

[0067] The seating area 812 may be provided with one or more step areas 812a. The step area 812a may be recessed in an outer surface of the seating area 812 such that the step area 812a may be in contact with the damper piston unit 840. By forming the step area 812a in the seating area 812, a contact area between the damper piston unit 840 and the seating area 812 may be minimized.

[0068] The step portion 812a may be formed along a circumferential direction of the seat portion 812. In addition, the step portion 812a may be formed along the circumferential direction of the damper housing body 811.

[0069] A plurality of step portions 812a may be arranged to be spaced apart from each other along the circumferential direction of the seat portion 812. In addition, the plurality of step portions 812a may be arranged to be spaced apart from each other along the circumferential direction of the damper housing body 811.

[0070] The plurality of step portions 812a may be arranged with radial support on a central portion of the seat portion 812. Additionally, the step portion 812a may be arranged with radial support on a central portion of the damper housing body 811.

[0071] The step portion 812a may be formed to have a cross-sectional shape of either a polygon with angled corners, such as a triangle or a square, or a rounded semicircle.

[0072] When the damper piston unit 840 is separated from the seat portion 812 by pressing the damper pressure unit 860 to be described below while the damper piston unit 840 is seated on the seat portion 812, resistance occurs at a contact surface between the damper piston unit 840 and the seat portion 812 due to the viscosity and surface tension of the lubricant. Due to the viscosity and surface tension of the lubricant, a feeling of difference and noise may occur during the initial operation of the pedal simulator 800.

[0073] By forming the step portion 812a in the seat portion 812, the contact area between the damper piston unit 840 and the seat portion 812 can be minimized, thereby reducing the influence of the viscosity and surface tension of the lubricant.

[0074] The damper holder unit 820 may be coupled to the damper housing unit 810. Additionally, the damper holder unit 820 may be coupled to one side of the damper housing body 811. The flap holder unit 820 may rotatably support the bolt body 311. The flap holder unit 820 may include a holder body 821 and a holder projection 822.

[0075] The holder body 821 may be formed in a hollow shape with an open end. The holder body 821 may be coupled to the damper housing body 811 of the damper housing unit 810 and may be moved together with the damper housing unit 810.

[0076] The holder protrusion 822 may be provided on the holder body 821. The holder protrusion 822 may protrude from an outer surface of the holder body 821 and be hollow.

[0077] The holder body 821 and the holder projection 822 may be connected to each other. A portion of the damping unit 850 may be accommodated inside the holder projection 822. A diameter of the holder projection 822 may be smaller than a diameter of the holder body 821. The holder projection 822 may be inserted into the bolt body 311.

[0078] The first bearing unit 830 may be provided on the damper holder unit 820. The first bearing unit 830 may be coupled to an outer surface of the damper holder unit 820 facing the bolt part 310. In addition, the first bearing unit 830 may be rotatably coupled to the outer surface of the holder body 821 to surround the outer periphery of the holder projection 822.

[0079] One end of the bolt body 311 can rest on the first bearing unit 830. The first bearing unit 830 can rotatably support the bolt body 311. The first bearing unit 830 can support the axial load of the screw bolt part 310.

[0080] The damper piston unit 840 can be slidably disposed in the damper housing unit 810. Additionally, the damper piston unit 840 can be movably received in the damper housing body 811. The damper piston unit 840 can be moved to separate from the seating portion 812 by pressing the damper pressure unit 860, and can be moved and seated on the seating portion 812 by the elastic force of the first elastic unit 870.

[0081] The damper unit 850 may be coupled to the damper piston unit 840. The damper unit 850 may be partially received within the holder projection 822 and may be compressed within the holder projection 822 by the movement of the damper piston unit 840.

[0082] The damper unit 850 may be manufactured to include an elastically deformable material. The damper unit 850 may include rubber, silicone, plastic, or the like as the elastically deformable material.

[0083] The damper pressure unit 860 may be coupled to the damper piston unit 840 to press the damper piston unit 840. The damper pressure unit 860 may include a push rod portion 861 and a first seat portion 862.

[0084] The push rod portion 861 may be rotatably coupled to an outer surface of the damper piston unit 840 in a connected manner. Furthermore, the push rod portion 861 may be caulked to the damper piston unit 840.

[0085] The first seat portion 862 is axially coupled to the push rod portion 861. Additionally, the push rod portion 861 may be coupled to the first seat portion 862 by penetrating the center of the first seat portion 862. The first elastic unit 870 may be placed on the first portion 862.

[0086] The first elastic unit 870 can be installed between the damper pressure unit 860 and the damper housing unit 810 to elastically support the damper pressure unit 860. One side of the first elastic unit 870 can be in contact with an outer surface of the first seat portion 862, the other side of the first elastic unit 870 can be in contact with the other side of the damper housing unit 810, and the first elastic unit 870 can provide an elastic force to the damper pressure unit 860, which is moved by an external force applied to the damper pressure unit 860.

[0087] The first elastic unit 870 can be compressed by the first seat portion 862, which is moved by the external force applied to the damper pressure unit 860. The compressed first elastic unit 870 can provide an elastic force (elastic restoring force) to the first seat portion 862 to return the first seat portion 862 to its original position. The first elastic unit 870 can be a coil spring surrounding the outer side of the push rod portion 861.

[0088] The operation of the vehicle brake device according to the embodiment of the present disclosure having the above-described configuration will be described as follows.

[0089] Fig. 9 is a cross-sectional view illustrating an operating state of the vehicle brake device according to the present embodiment.

[0090] Referring to Fig. 9, the pedal simulator 800 becomes unable to move in a deceleration section of the vehicle due to the elastic force of the second elastic unit 400 and the hydraulic reaction force. In such a case, the damper unit 850 can be compressed by pressing the damper pressure unit 860.

[0091] When the motor 10 is actuated by a brake signal from a vehicle control device (not shown) generated when a user steps on the pedal and rotates the gear unit 200, the gear unit 200 rotates the screw body 311.

[0092] By rotating the screw body 311, the nut part 320 moves along the screw axis 312 (left direction according to Fig.9), and hydraulic braking pressure is generated in the master cylinder unit 600 by the piston unit 500 coupled to the nut body 321. In such a case, the second elastic unit 400 is compressed by the movement of the nut part 320.

[0093] The screw bolt part 310 is not moved by the hydraulic reaction force exerted on the screw bolt part 310 by the piston unit 500 due to the movement of the nut part 320 and the elastic force of the compressed second elastic unit 400, so that the position of the screw bolt part 310 is fixed.

[0094] The position of the screw bolt part 310 is fixed, so the position of the pedal simulator 800 is also fixed. In addition, the damper housing unit 810 is immobilized by the elastic force of the second elastic unit 400 and the hydraulic reaction force.

[0095] When the damper pressure unit 860 is compressed by an external force, the damper pressure unit 860 moves toward the damper holder unit 820. While the damper pressure unit 860 moves, the first elastic unit 870 is compressed and deformed by pressing the first portion 862.

[0096] When an external force is applied to the damper pressure unit 860 and the push rod portion 861 presses the damper piston unit 840 seated on the seat portion 812, the damper piston unit 840 moves inward into the damper holder unit 820 to compress the damper unit 850. In such a case, a user may feel an initial braking sensation.

[0097] The pedal simulator 800 and the vehicle braking device 1 including the same according to the embodiment of the present disclosure can improve the regenerative braking performance and increase the amount of regenerative braking.

[0098] The pedal simulator 800 and the vehicle brake device 1 incorporating the same according to the embodiment of the present disclosure can minimize the addition of parts and implement a pedal feel without increasing a structure.

[0099] The pedal simulator 800 and the vehicle brake device 1 including the same according to the embodiment of the present disclosure can improve a feeling of the difference in pedal operating force during regenerative braking.

[0100] Although the present disclosure has been described with reference to the embodiments illustrated in the drawings, the embodiments of the disclosure are for illustrative purposes only, and those skilled in the art will understand that various modifications and other equivalent embodiments are possible from the embodiments. Therefore, the true technical scope of the present disclosure should be defined by the following claims.

Claims

[1] Pedal simulator, comprising: a damper housing unit; a damper holder unit coupled to the damper housing unit; a first bearing unit rotatably disposed on the damper holder unit; a damper piston unit slidably received within the damper housing unit; a damper unit coupled to the damper piston unit, received within the damper housing unit, and compressed by movement of the damper piston unit; a damper pressure unit coupled to the damper piston unit for compressing the damper piston unit; and a first elastic unit disposed between the damper pressure unit and the damper housing unit for elastically supporting the damper pressure unit. [2] Pedal simulator according to claim 1, wherein the damper housing unit comprises: a damper housing body having a side to which the damper holder unit is coupled, wherein the damper piston unit and the damper unit are arranged in the damper housing body; and a seating portion protruding from an inner peripheral surface of the damper housing body and extending along a circumferential direction of the damper housing body, wherein the damper piston unit is seated on the seating portion by an elastic force of the first elastic unit. [3] A pedal simulator according to claim 2, wherein the seating portion comprises one or more step portions recessed into an outer surface of the seating portion in contact with the damper piston unit. [4] The pedal simulator according to claim 3, wherein the step portion is arranged along a circumferential direction of the seat portion. [5] The pedal simulator according to claim 4, wherein the one or more step portions comprise a plurality of step portions spaced apart from each other along the circumferential direction of the seat portion. [6] A pedal simulator according to claim 5, wherein each of the step portions extends radially from a central region of the seating area. [7] A pedal simulator according to claim 6, wherein each of the step portions has a cross-sectional shape of either a polygon or a semicircle. [8] Pedal simulator according to one of claims 1 to 7, wherein the damper holder unit comprises: a holder body coupled to the damper housing unit and to which the first bearing unit is rotatably coupled; and a holder projection projecting from an outer surface of the holder body. [9] Pedal simulator according to one of claims 1 to 8, wherein the damper pressure unit comprises: a push rod section rotatably coupled to the damper piston unit; and a first seat portion axially coupled to the push rod portion, wherein the first elastic unit rests on the first seat portion. [10] Vehicle braking device, comprising: a housing unit; a gear unit rotatably disposed in the housing unit and rotated by the action of a rotational force of a motor; a motion conversion unit disposed within the housing unit and coupled to the gear unit for converting a rotational motion of the gear unit into a linear motion; a second elastic unit configured to elastically support the motion conversion unit within the housing unit; a piston unit movably coupled to the motion conversion unit; a master cylinder unit coupled to one side of the housing unit and configured to generate hydraulic pressure by inserting the piston unit; a second bearing unit disposed within the housing unit for rotatably supporting the gear unit; and the pedal simulator according to any one of claims 1 to 9, wherein the pedal simulator is movably arranged on the other side of the housing unit and coupled to the motion conversion unit. [11] A vehicle braking device according to claim 10, wherein the motion conversion unit comprises: a screw bolt member slidably coupled to the gear unit and rotated together with the gear unit; and a nut part coupled to the bolt part and moved along the bolt part. [12] A vehicle braking device according to claim 11, wherein the piston unit is coupled to the nut part and is moved together with the nut part. [13] A vehicle braking device according to claim 11 or 12, wherein the second elastic unit elastically supports the nut member. [14] A vehicle braking device according to claim 13, wherein the nut member comprises: a nut body spirally coupled to the screw bolt part; a second seating portion protruding from an outer peripheral surface of the nut body, the second elastic unit being seated on the second seating portion; and a rotation preventing portion disposed on the nut body to limit rotation of the nut body. [15] A vehicle braking device according to claim 14, wherein the rotation preventing portion comprises: a projection projecting from an outer peripheral surface of the second seating portion and contacting an inner surface of the housing unit. [16] A vehicle braking device according to claim 14 or 15, wherein the bolt member comprises: a screw body axially coupled to an inner side of the gear unit, the screw body being slidably movable and having a hollow prism shape; and a screw shaft arranged at one end of the screw body and spirally coupled to the nut body, wherein the screw body is moved linearly along the screw shaft.

Images