CN-121993515-A - Brake device for vehicle

CN121993515ACN 121993515 ACN121993515 ACN 121993515ACN-121993515-A

Abstract

A brake device for a vehicle includes a caliper body provided with a cylinder, a nut screw rotatably disposed on the cylinder, a bolt screw movable in a first direction or in a second direction opposite to the first direction with rotation of the nut screw, a piston movably disposed in the cylinder and configured to be moved in the first direction by pressurization of the bolt screw and to interfere with the bolt screw to restrict rotation of the bolt screw, and a retainer fastened to the cylinder and configured to interfere with the piston to restrict rotation of the piston. With the present disclosure, the second interference portion formed on the piston interferes with the fourth interference portion formed on the retainer, thereby preventing rotation of the piston, and the third interference portion formed on the bolt head portion interferes with the first interference portion formed on the piston, thereby preventing rotation of the bolt shank.

Inventors

Fu Xiangbi
Shen Chongzhi
Quan Daxiong
YIN BAOLAN
PU XIANGJUN
BIAN WENHUAN

Assignees

现代摩比斯株式会社

Dates

Publication Date: 20260508
Application Date: 20250306
Priority Date: 20241104

Claims (10)

1. A braking device for a vehicle, the braking device comprising: a caliper body provided with a cylinder; a nut screw rotatably disposed on the cylinder; a bolt screw movable in a first direction or in a second direction opposite to the first direction with rotation of the nut screw; A piston movably disposed in the cylinder and configured to move in the first direction by pressurization of the bolt screw, and the piston interfering with the bolt screw to restrict rotation of the bolt screw, and A retainer secured to the cylinder and configured to interfere with the piston to limit rotation of the piston.
2. The braking device for a vehicle according to claim 1, wherein the piston includes: A piston body portion into which the bolt screw is inserted; a first interference portion provided on an inner peripheral surface of the piston body portion and configured to interfere with the bolt screw, and A second interference portion provided on an outer peripheral surface of the piston body portion and configured to interfere with the retainer.
3. The braking device for a vehicle according to claim 2, wherein: The first interference portion is formed to protrude from an inner peripheral surface of the piston body portion, and The second interference portion is formed to be recessed on an outer peripheral surface of the piston body portion.
4. A braking apparatus for a vehicle according to claim 3, wherein the second interference portion extends along a central axis of the piston.
5. The braking device for a vehicle according to claim 2, wherein the bolt screw includes: a bolt body portion coupled to the nut screw by a ball member; A bolt head portion configured to pressurize the piston body portion, and And a third interference portion provided on an outer peripheral surface of the bolt head portion and capable of being brought into contact with the first interference portion.
6. The brake device for a vehicle according to claim 5, wherein the third interference portion is formed as a flat surface by cutting out a part of an outer peripheral surface of the bolt head portion.
7. The braking device for a vehicle according to claim 2, wherein the retainer includes: a retainer body portion having an annular shape and disposed between the cylinder and the piston, and And a fourth interference portion provided on an inner peripheral surface of the holder body portion and capable of contacting the second interference portion.
8. The braking device for a vehicle according to claim 7, wherein the fourth interference portion is formed to protrude from an inner peripheral surface of the holder body portion.
9. The brake device for a vehicle according to claim 7, wherein the retainer further includes a damper portion coupled to the retainer body portion and contactable with the piston.
10. The braking apparatus for a vehicle according to claim 9, wherein the damper portion is further provided with a convex portion that is disposed on the piston.

Description

Brake device for vehicle Technical Field Exemplary embodiments of the present disclosure relate to a brake apparatus for a vehicle, and more particularly, to a brake apparatus for a vehicle that can ensure stable braking performance. Background In general, a vehicle braking device pushes a piston by a driving force to bring a pad and a disc into close contact, and brakes a vehicle using friction between the pad and the disc. In a vehicle braking device, an electromechanical brake (electro mechanical brake, EMB) does not use hydraulic pressure, but has a motor-driven actuator mounted on a caliper for pressurizing a piston to generate braking force by a mechanism that converts rotational movement of a screw into linear movement of a nut or converts rotational movement of a nut into linear movement of a screw. The EMB is capable of active braking and independent braking of each wheel, thereby enabling not only general main braking, but also each additional function such as an anti-lock braking system (anti-lock brake system, ABS), electronic stability control (electric stability control, ESC), traction control system (traction control system, TCS) and automatic emergency braking (automatic emergency braking, AEB), and higher performance due to the absence of hydraulic transmission delays. The related art of the present disclosure is disclosed in korean patent application laid-open No. 10-2024-0054695 (published at 26 of 4/2024 and entitled "brake apparatus for vehicle"). Disclosure of Invention An object of the present disclosure is to provide a brake device for a vehicle, which can ensure stable braking performance. A brake device for a vehicle according to the present disclosure includes a caliper body provided with a cylinder, a nut screw rotatably disposed on the cylinder, a bolt screw movable in a first direction or in a second direction opposite to the first direction with rotation of the nut screw, a piston movably disposed in the cylinder and configured to be moved in the first direction by pressurization of the bolt screw, and the piston interfering with the bolt screw to limit rotation of the bolt screw, and a retainer fastened to the cylinder and configured to interfere with the piston to limit rotation of the piston. The piston may include a piston body portion into which the bolt screw is inserted, a first interference portion provided on an inner circumferential surface of the piston body portion and configured to interfere with the bolt screw, and a second interference portion provided on an outer circumferential surface of the piston body portion and configured to interfere with the retainer. The first interference portion may be formed to protrude from an inner peripheral surface of the piston body portion, and the second interference portion may be formed to be recessed on an outer peripheral surface of the piston body portion. The second interference portion may extend in a direction parallel to the first direction and the second direction. The bolt screw may include a bolt body portion coupled to the nut screw through a ball member, a bolt head portion configured to pressurize the piston body portion, and a third interference portion provided on an outer peripheral surface of the bolt head portion and capable of contacting the first interference portion. The third interference portion may be formed as a flat surface by cutting out a part of the outer peripheral surface of the bolt head portion. The retainer may include a retainer body portion having an annular shape disposed between the cylinder and the piston, and a fourth interference portion provided on an inner peripheral surface of the retainer body portion and capable of contacting the second interference portion. The fourth interference portion may be formed to protrude from an inner peripheral surface of the holder body portion. The retainer may further include a damper portion coupled to the retainer body portion and contactable with the piston. The damper portion may be further provided with a convex portion disposed on the piston. By the present disclosure, the second interference portion formed on the piston interferes with the fourth interference portion formed on the retainer to prevent rotation of the piston, and the third interference portion formed on the bolt head portion interferes with the first interference portion formed on the piston to prevent rotation of the bolt shank. With the present disclosure, the elastic force of the convex portion formed on the damper portion is applied to the piston toward the center portion of the piston, thereby keeping the piston centered. With the present disclosure, the grooves formed between the plurality of convex portions may serve as grease (lubricant) pockets to form a stable lubricating film when the piston moves, thereby minimizing frictional resistance of the piston. Drawings Fig. 1 is a perspective view of a brake device for a vehicle according to an embodiment of the present d