KR20210083672A - Electromechanical brake - Google Patents

Abstract

An electromechanical brake comprises: an electric actuator; a gear unit having a plurality of gears configured to be connected to the electric actuator to transmit rotational power of the electric actuator; a linear driving unit connected to the gear unit to convert the rotational power transmitted through the gear unit into linear power to be operated to provide force of compressing a brake pad; a housing storing the gear unit; and an emergency releasing member of which a portion is disposed in the outside of the housing and configured to rotate a driving element of the linear driving unit to release a braking state.

Description

electromechanical brake

The present invention relates to an electromechanical brake of a vehicle.

BACKGROUND ART An electromechanical brake of a vehicle, so-called electromechanical brake (EMB), has a method of driving a brake pad by the power of a motor and is in the spotlight as a brake system that can replace the conventional hydraulic brake. An EMB in which a motor is installed in a caliper is also called a Motor on caliper brake (MoC) or an Electric parking brake (EPB).

The electromechanical brake requires a structure for transmitting the rotational force of the motor to the brake pad, and an electromechanical brake having a gear unit for transmitting the rotational force of the motor and a spindle structure operating in conjunction with the gear unit has been proposed. The spindle shaft is configured to rotate by the gear unit, and the spindle nut screwed to the spindle shaft is configured to make a linear motion by the rotation of the spindle shaft. The linear movement of the spindle nut causes a linear movement of the piston configured to press the brake pad, and the brake pad is pressed by the linear movement of the piston to compress the brake disc, thereby braking by frictional force. The piston is arranged to move linearly in a cylinder housing, and a seal and a boot are arranged between the cylinder housing and the piston for sealing and preventing foreign substances from entering.

An emergency parking release function is required in case the EMB does not work due to battery discharge, gear unit failure, or other reasons. Existing electromechanical brakes have a structure that has no choice but to release the parking state by forcibly turning the spindle by disassembling the motor to release emergency braking. Due to this, there was a problem that the emergency release operation requires a lot of time.

Unexamined Patent Publication No. 2014-0003839 (published date: 2014.01.10) Unexamined Patent Publication No. 2019-0043173 (published date: 2019.04.29)

SUMMARY OF THE INVENTION An object of the present invention is to provide an electromechanical brake configured to release a parking state in a simple manner without disassembling the motor.

An electromechanical brake according to an embodiment of the present invention includes an electric actuator, a gear unit connected to the electric actuator and configured to transmit rotational power of the electric actuator, a gear unit including a plurality of gears, the gear unit is connected to the gear unit A linear drive unit operable to convert rotational power transmitted through a linear power to linear power to provide force for pressing the brake pad, a housing for accommodating the gear unit, and a part disposed outside the housing and the braking state is released and an emergency release member configured to be able to rotate the drive element of the linear drive unit so as to be possible.

The emergency release member may be configured to be connected to an output element of the gear unit that transmits a driving force to a drive element of the linear drive unit to rotate the output element.

The gear unit may include a planetary gear set that transmits the driving force of the electric actuator to the linear drive unit, and the driving element may be a carrier of the planetary gear set.

The linear drive unit may include a spindle shaft fastened to the carrier to rotate with the carrier, and a spindle nut screwed to the spindle shaft and configured to linearly move by rotation of the spindle shaft.

The emergency release member may include a shaft portion coupled to the driving element, and a manipulation portion provided at an end of the shaft.

The manipulation unit may include a polygonal protrusion.

The manipulation unit may include a polygonal fastening groove.

The manipulation unit may have a curved shape from the manipulation unit.

According to the present invention, the driving element of the linear drive unit can be rotated without disassembling the electric actuator, so that the braking state can be released through a simple operation.

1 is a perspective view of an electromechanical brake according to an embodiment of the present invention;
FIG. 2 is a cross-sectional view taken along line II-II of FIG. 1 .
3 is a perspective view of an electromechanical brake according to another embodiment of the present invention.
4 is a cross-sectional view taken along line IV-IV of FIG. 3 .
5 is a perspective view of an electromechanical brake according to another embodiment of the present invention.
6 is a cross-sectional view taken along line VI-VI of FIG. 5 .

Hereinafter, an embodiment of the present invention will be described in detail with reference to the accompanying drawings.

An electromechanical brake (EMB) according to an embodiment of the present invention implements braking by using a driving force of an electric actuator, for example, the motor 10 . The electromechanical brake may be implemented in the form of a caliper brake, and may be configured to press the brake pad by the driving force of the motor 10 to adhere to the disc to achieve braking.

1 and 2 , the motor 10 may be disposed in the housing 100 , and the motor 10 may include an output shaft 11 for outputting rotational power.

The gear unit 20 is connected to the motor 10 and configured to transmit rotational power of the motor 10 . The gear unit 20 may include a motor output gear 21 , a first intermediate gear 22 , a second intermediate gear 23 , and a planetary gear set 24 connected to the output shaft 11 of the motor 10 . can

The motor output gear 21 may be coupled to the output shaft 11 to rotate together with the output shaft 11 of the motor 10 . The first intermediate gear 22 may be configured to be rotated while being meshed with the motor output gear 21 . The second intermediate gear 23 is meshed with the first intermediate gear 22 , and may be configured to transmit rotational power to the planetary gear set 24 . The planetary gear set 24 includes a sun gear 241 , a planetary gear 242 , a ring gear 243 , and a carrier 244 connected to the planetary gear 243 . may include The ring gear 243 of the planetary gear set 20 may be configured to act as a stationary element and the carrier 244 to act as a rotating element, through which the rotational power is transmitted to the linear drive unit 30 . can be

The linear drive unit 30 converts rotational power transmitted through the gear unit 20 into linear power. The drive unit 30 may be implemented with a conventionally known spindle structure that converts a rotational motion into a linear motion. Referring to FIG. 2 , the linear driving unit 30 may include a spindle shaft 31 and a spindle nut 32 .

The spindle shaft 31 may be connected to the carrier 244 for rotation with the carrier 244 of the planetary gear set 24 . For example, the carrier 243 and the spindle shaft 244 of the planetary gear set 24 may be fastened to each other through spline coupling, whereby the carrier 243 and the spindle shaft 31 may rotate together. .

The spindle shaft 31 is installed to pass through the spindle nut 32 , and the spindle shaft 31 and the spindle nut 32 are fastened to each other by screw coupling. When rotation of the spindle shaft 31 occurs, the spindle nut 32 is installed to enable linear movement in a state in which rotation is blocked so that linear movement of the spindle nut 32 can occur by screwing. As shown in FIG. 2 , the spindle nut 32 may be constrained to the piston 33 capable of pressing the brake pad 200 installed in the caliper housing 400 by linear movement, and the piston 33 may It may be installed to enable linear movement in a state in which rotation is blocked. When the piston 34 moves downward in FIG. 2 and presses the brake pad 200 , the brake pad 200 is in close contact with a disk (not shown) and braking is performed. The rotational power of the motor 10 is transmitted to the spindle shaft 31 of the linear drive unit 30 through the gear unit 20 , and the rotation of the spindle shaft 31 is a linear movement of the screwed spindle nut 32 . causes As the piston 34 moves linearly with the spindle nut 32 , the brake pad 200 is pressed.

The piston 33 is arranged movably linearly within the cylinder housing 34 . The cylinder housing 34 is formed so that the side facing the brake pad 200 is opened, and the piston 33 may be disposed in the cylinder housing 34 so that the tip is exposed through the open inlet of the cylinder housing 34 . . A boot 35 and a seal 36 may be disposed between the piston 33 and the cylinder housing 34 . The piston 33 passes through the base 341 of the cylinder housing 34 , and a bearing 37 may be installed between the piston 33 and the base 341 . The bearing 37 may be disposed between the piston 33 and the base 341 of the cylinder housing 34 to rotatably support the spindle shaft 32 in the axial direction.

According to an embodiment of the present invention, an emergency release member 40 for rotating the spindle shaft 31 in the braking release direction from the outside of the housing 100 is included. 1 and 2 , the emergency release member 40 is configured in the form of a shaft and is an output element of the gear unit 20 fastened to the spindle shaft 31 , that is, the carrier 244 of the planetary gear set 24 . can be connected to The emergency release member 40 may include a shaft part 41 connected to the carrier 244 to rotate together with the carrier 244 , and an operation part 42 provided at an outer end of the shaft part 41 . 1 and 2 , the manipulation unit 42 may be disposed outside the housing 100 to be operable from the outside. The manipulation unit 42 may be formed to be rotated by a tool such as a wrench, and may be formed of, for example, a polygonal (eg, hexagonal) protrusion. The spindle shaft 31 can be rotated in the braking releasing direction by rotating the emergency releasing member 40 in the braking releasing direction by fastening the operating part 42 with a tool such as a wrench, thereby releasing the braking state.

Hereinafter, another embodiment of the present invention will be described with reference to FIGS. 3 and 4 . Since parts except for the emergency release member 140 are the same as in the embodiments of FIGS. 1 and 2 , descriptions of the same parts will be omitted.

The emergency release member 140 includes a shaft portion 141 and a manipulation unit 142 , and the manipulation unit 142 includes a fastening groove 143 for fastening with an external tool. The emergency release member 140 may be rotated by fastening the tool to the fastening groove 143 .

Hereinafter, another embodiment of the present invention will be described with reference to FIGS. 5 and 6 . Since parts except for the emergency release member 240 are the same as in the embodiments of FIGS. 1 and 2 , a description of the same parts will be omitted.

The emergency release member 240 includes a shaft portion 241 and a manipulation unit 242 , and the manipulation unit 242 has a shape bent from the shaft unit 241 . The emergency release member 240 may be rotated by holding the bent manipulation unit 242 using a tool.

Although the embodiment of the present invention has been described above, the scope of the present invention is not limited thereto, and it is easily changed by a person skilled in the art from the embodiment of the present invention and recognized as equivalent. including all changes and modifications to the scope of

10: motor
100: housing
20: gear unit
21: motor output gear
22: first intermediate gear
23: second intermediate gear
24: planetary gear set
30: linear drive unit
31: spindle shaft
32: spindle nut
33: piston
34: cylinder housing
35: boot
36: seal
37: bearing
40, 140, 240: emergency release member
41, 141, 241: shaft part
42, 142, 242: control panel
200: brake pad

Claims (8)

electric actuator,
a gear unit connected to the electric actuator and including a plurality of gears configured to transmit rotational power of the electric actuator;
a linear drive unit connected to the gear unit and operative to convert rotational power transmitted through the gear unit into linear power to provide a force capable of pressing the brake pads;
a housing accommodating the gear unit; and
an emergency release member, a portion of which is disposed outside the housing and configured to rotate a drive element of the linear drive unit to release a braking state
electromechanical brakes comprising In claim 1,
and the emergency release member is connected to an output element of the gear unit that transmits a driving force to a drive element of the linear drive unit and is configured to rotate the output element. In claim 2,
the gear unit includes a planetary gear set for transmitting the driving force of the electric actuator to the linear driving unit;
The drive element is a carrier of the planetary gear set.
electromechanical brake. In claim 3,
The linear drive unit is
a spindle shaft coupled to the carrier for rotation with the carrier; and
A spindle nut screwed to the spindle shaft and configured to linearly move by rotation of the spindle shaft
electromechanical brakes comprising In claim 1,
The emergency release member is
a shaft portion fastened to the drive element; and
an operation unit provided at the end of the shaft
electromechanical brakes comprising In claim 5,
The operation unit is an electromechanical brake including a polygonal protrusion. In claim 5,
The operation part is an electromechanical brake including a polygonal fastening groove. In claim 5,
The operation part is an electromechanical brake having a shape bent from the operation part.

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