KR-20260062719-A - BRAKE DEVICE FOR VEHICLE
Abstract
The present invention relates to a braking device for a vehicle, comprising: a cylinder portion having a port; a motor portion generating rotational power; a screw shaft disposed inside the cylinder portion and rotating axially by receiving rotational power from the motor portion; a nut portion coupled to the screw shaft and reciprocating in the axial direction of the screw shaft according to the rotation of the screw shaft; a sleeve portion disposed between the cylinder portion and the screw shaft and having a cut-off hole portion communicating with the port; a piston portion coupled to the nut portion and having a head portion reciprocating inside the sleeve portion according to the reciprocating movement of the nut portion; and a sealing portion disposed in the cylinder portion spaced apart from the cut-off hole portion in the forward movement direction of the piston portion and capable of sealing the space between the cylinder portion and the sleeve portion at multiple points.
Inventors
- 피재훈
Assignees
- 현대모비스 주식회사
Dates
- Publication Date
- 20260507
- Application Date
- 20241029
Claims (6)
- A cylinder part equipped with a port; Motor unit that generates rotational power; A screw shaft disposed inside the cylinder part and rotated axially by receiving rotational power from the motor part; A nut portion coupled to the screw shaft and reciprocating in the axial direction of the screw shaft according to the rotation of the screw shaft; A sleeve portion disposed between the cylinder portion and the screw shaft and having a cut-off hole portion communicating with the port; A piston portion having a head portion coupled to the nut portion and reciprocating within the sleeve portion according to the reciprocating movement of the nut portion; and A braking device for a vehicle characterized by including a sealing portion disposed in the cylinder portion so as to be spaced apart from the cut-off hole portion in the forward movement direction of the piston portion, and capable of sealing at multiple points between the cylinder portion and the sleeve portion.
- In paragraph 1, The sealing portion above includes a first contact portion capable of contacting the cylinder portion and the sleeve portion; and A braking device for a vehicle characterized by including a second contact portion that is connected to the first contact portion in the longitudinal direction of the sleeve portion, is positioned closer to the cut-off hole portion than the first contact portion, and is capable of contacting the cylinder portion and the sleeve portion.
- In paragraph 2, A braking device for a vehicle characterized in that the first contact portion and the second contact portion are formed symmetrically.
- In paragraph 3, A braking device for a vehicle characterized in that the thickness of the connection portion between the first contact portion and the second contact portion is smaller than the maximum thickness of the first contact portion and the second contact portion.
- In paragraph 4, A vehicle braking device characterized by the sealing portion having a cross-section formed in the shape of a figure eight.
- In paragraph 4, A vehicle braking device characterized in that the length of the sealing portion in the longitudinal direction is longer than the length of the sleeve portion in the radial direction.
Description
Brake Device for Vehicle The present invention relates to a braking device for a vehicle, and more specifically, to a braking device for a vehicle capable of converting the rotational motion of a screw shaft, which is rotated by receiving rotational force from a motor part, into linear motion of a piston part. Generally, due to the characteristics of electric vehicle braking systems, a device is required that converts the rotational motion of a motor into the linear motion of a piston inside a cylinder to generate brake fluid pressure. A ball screw device, which is a device for converting the rotational motion of a motor into linear motion and comprises a screw shaft that rotates by receiving the rotational force of the motor, a nut that is coupled to the screw shaft via a ball and moves in the axial direction of the screw shaft, and a piston coupled to the nut that pressurizes the working fluid inside the cylinder, is applied to an electric brake device. The background technology of the present invention is disclosed in Korean Published Patent Application No. 10-2021-0064367 (published June 2, 2021; Title of Invention: Hydraulic Unit for Hydraulic Vehicle Brake System). FIG. 1 is a cross-sectional view showing a vehicle braking device according to one embodiment of the present invention. FIG. 2 is a perspective view of a cylinder portion according to one embodiment of the present invention, viewed from one direction. Figure 3 is a perspective view of the cylinder portion of Figure 2 viewed from a different direction. FIG. 4 is a cross-sectional view schematically showing a braking device for a vehicle according to one embodiment of the present invention. FIG. 5 is a cross-sectional view showing a sealing portion according to one embodiment of the present invention. FIG. 6 is a drawing showing the shape of a sealing part deformed according to an axial alignment state according to one embodiment of the present invention. FIG. 7 is a diagram showing the operating state in which a piston part advances inside a cylinder part in a vehicle braking device according to one embodiment of the present invention. FIG. 8 is a diagram showing the operating state in which a piston part retracts inside a cylinder part in a vehicle braking device according to one embodiment of the present invention. Hereinafter, embodiments of a vehicle braking device according to the present invention will be described with reference to the attached drawings. In this process, the thickness of lines or the size of components shown in the drawings may be exaggerated for clarity and convenience of explanation. Furthermore, the terms described below are defined considering their functions in the present invention, and these may vary depending on the intention or convention of the user or operator. Therefore, the definitions of these terms should be based on the content throughout this specification. FIG. 1 is a cross-sectional view showing a vehicle braking device according to an embodiment of the present invention, FIG. 2 is a perspective view of a cylinder part according to an embodiment of the present invention viewed from one direction, FIG. 3 is a perspective view of the cylinder part of FIG. 2 viewed from another direction, FIG. 4 is a cross-sectional view schematically showing a vehicle braking device according to an embodiment of the present invention, FIG. 5 is a cross-sectional view showing a sealing part according to an embodiment of the present invention, FIG. 6 is a drawing showing a shape of the sealing part deformed according to an axial alignment state according to an embodiment of the present invention, FIG. 7 is a drawing showing an operating state in which a piston part advances inside a cylinder part in a vehicle braking device according to an embodiment of the present invention, and FIG. 8 is a drawing showing an operating state in which a piston part retracts inside a cylinder part in a vehicle braking device according to an embodiment of the present invention. Referring to FIGS. 1 to 8, a vehicle braking device according to one embodiment of the present invention includes a cylinder part (200), a motor part (300), a screw shaft (400), a nut part (500), a piston part (600), a sleeve part (700), and a sealing part (750), which are described in detail as follows. The cylinder portion (200) is positioned inside the housing portion (100) and can support the torque generated when hydraulic pressure is formed due to the reciprocating movement of the piston portion (600). The housing portion (100) according to the present embodiment may be formed in a hollow shape with an internal space and may be press-fitted to the cylinder portion (200). The housing portion (100) may be provided on the outer side (left side in Fig. 1) of the cylinder portion (200). The cylinder portion (200) may be assembled to the housing portion (100) such that concentricity is regulated. The cylinder portion (200) may be formed in a hollow shape. A sleeve