KR20180024930A - Electric disk brake - Google Patents

Abstract

According to the present invention, disclosed is an electric disk brake. According to the present invention, the electric disk brake comprises a caliper housing which comprises: a carrier in which a pair of pad plates are installed to allow forward and backward movement; and a cylinder slidably installed on the carrier to have a piston, whose inside is formed in a cup shape, installed to allow forward and backward movement by a brake oil pressure. The electric disk brake comprises: a sub-cylinder installed on the cylinder to receive a separate brake oil pressure for braking for parking; a parking piston combined with the piston to be installed on the sub-cylinder to allow forward and backward movement; a reservoir for parking to store oil to supply brake oil pressure to the sub-cylinder; a housing combined with the caliper housing, which comprises a communication hole communicating with a penetrating hole which penetrates the rear side of the sub-cylinder and cylinder, and an oil flow path to connect the communication hole and reservoir for parking; and a parking driving unit placed in the housing to move forward and backward in accordance with the application of power and to pressurize and depressurize the inside of the sub-cylinder. The present invention minimizes operating noise, simplifies the composition, and improves braking responsiveness.

Description

[0001] The present invention relates to an electric disk brake,

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an electric disk brake, and more particularly, to an electric disk brake capable of simplifying a structure and improving braking responsiveness.

Generally, an electric disk brake performs a parking brake function for braking a vehicle by forcibly pressing a friction pad on both sides of a disk rotating together with a wheel of the vehicle, and for electrically operating the parking brake to keep the vehicle in a stopped state Device. The electric disk brake includes a pair of pad plates disposed on both sides of the disk for pressing the disk to generate a braking force, a carrier for supporting the pair of pad plates, A caliper housing installed as far as possible and having a piston moving by braking hydraulic pressure, and an actuator for actuating the piston by a mechanical mechanism.

The actuator of the electric disk brake is equipped with a motor, a speed reducer composed of a plurality of gears, and the like, and is used for parking brake. For example, an electric disk brake provided with an actuator is disclosed in, for example, JP-A-10-2010-0039072 and JP-A-2009-0057057. According to the disclosed document, the electric disk brake performs the parking brake by transmitting the driving force output through the motor and the speed reducer composed of the plurality of gears to the nut-spindle unit installed in the cylinder of the caliper housing.

However, such an electric disc brake has a problem that operation noise and rattle noise are generated due to the driving of the motor, the coupling relation with the plurality of gears, and the pressing structure with the piston due to the operation of the nut-spindle unit.

Open Patent KR 10-2010-0039072 (Mando Co., Ltd.) 2010. 04. 15. Open Patent KR 10-2009-0057057 (Continental Tevez) 2009. 06. 03, Drawing 2

The electric disc brake according to the embodiment of the present invention eliminates the motor and the plurality of gear assembly structures to minimize the operating noise and reduce the number of components, thereby simplifying the structure and improving the braking responsiveness.

According to an aspect of the present invention, there is provided a caliper, comprising: a carrier in which a pair of pad plates are installed so as to be movable forward and backward; and a cylinder provided slidably on the carrier and provided with a cylinder in which a cup- 1. An electric disk brake including a housing, comprising: a sub cylinder installed in the cylinder to receive a separate braking hydraulic pressure for parking brake; A parking piston coupled to the piston and installed to be movable forward and backward to the sub-cylinder; A parking reservoir in which oil is stored to supply braking hydraulic pressure to the sub cylinder; A communication hole which is coupled to the caliper housing and communicates with the through-hole passing through the sub-cylinder and the rear portion of the cylinder, and a housing having an oil flow path connecting the communication hole and the parking reservoir; And a parking driving part which is provided in the housing and moves forward and backward according to power application and presses and releases the inside of the sub cylinder.

The through hole and the communication hole are connected to each other in a straight line, and the inside of the through hole is formed as a pressurizing chamber. The parking driving unit includes a plunger movably installed in the housing. A rod installed on the plunger and moving together with the plunger to press the pressurizing chamber; And a coil assembly installed to surround the outer side of the plunger and moving the plunger forward and backward according to application of power.

The coil assembly may include: a cylindrical bobbin having the plunger movably disposed therein and having a plurality of mounting portions defined in a longitudinal direction thereof; A permanent magnet installed at a mounting portion provided at the center of the outer periphery of the bobbin; And a coil wound around a mounting portion formed on both sides of the outer periphery of the bobbin with the permanent magnet interposed therebetween.

In addition, the permanent magnet may have a first magnetic field formed from the inner center to the outer center of the bobbin.

In addition, the plunger may be provided to be positioned at one end of both ends of the housing by the first magnetic field.

The plunger is moved by a second magnetic field generated by a positive (+) power source or a negative (-) power source applied to the coil, and when the power source applied to the coil is cut off, The state of being positioned at the end can be maintained.

The front end of the parking piston may have a protrusion penetrating through the piston to be in contact with the piston, and a clip may be installed on the protrusion so that the piston and the parking piston are not separated from each other.

The electric disc brake according to an embodiment of the present invention is linearly moved according to an applied power source and presses the oil to generate a parking braking force, thereby making it possible to simplify the structure compared to a conventional motor and a plurality of gear connection structures have.

Further, by removing the structure of the conventional actuator, it is possible to minimize the operating noise as well as to reduce the number of components, thereby reducing the cost.

On the other hand, it operates according to the power application and pressurizes the oil to generate the parking brake force, thereby improving the operating responsiveness and minimizing the driving force loss for generating the parking brake force.

BRIEF DESCRIPTION OF THE DRAWINGS The present invention will be described in detail with reference to the following drawings, which illustrate preferred embodiments of the present invention, and thus the technical idea of the present invention should not be construed as being limited thereto.
1 is a side sectional view schematically showing an electric disc brake according to an embodiment of the present invention.
2 is a partially enlarged view showing a state in which a parking apparatus provided in an electric disk brake according to an embodiment of the present invention is installed in a caliper housing.
3 is a view showing an operating state of an electric disc brake according to an embodiment of the present invention in accordance with a braking hydraulic pressure.
FIGS. 4 to 6 are diagrams showing a state in which parking is actuated through a parking apparatus provided in an electric disk brake according to an embodiment of the present invention.
7 is a view illustrating a state in which the parking operation is released through a parking apparatus provided in an electric disk brake according to an embodiment of the present invention.

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 present invention to a person having ordinary skill in the art to which the present invention belongs. The present invention is not limited to the embodiments shown herein but may be embodied in other forms. For the sake of clarity, the drawings are not drawn to scale, and the size of the elements may be slightly exaggerated to facilitate understanding.

FIG. 1 is a side sectional view schematically showing an electric disc brake according to an embodiment of the present invention, and FIG. 2 is an enlarged view showing a state where a parking apparatus provided in the electric disc brake is installed in a caliper housing.

1 and 2, an electric disk brake 100 according to an embodiment of the present invention includes a pair of pad plates 111 (not shown) for pressing both sides of a disk D rotating together with a wheel A caliper housing 120 provided with a cylinder 110 slidably installed on the carrier 110 and provided with a cylinder 123 in which a piston 121 can be moved forward and backward by braking oil pressure, And a parking device for providing a separate braking hydraulic pressure to the sub cylinder 130 installed in the cylinder 123 to press the parking piston 140.

The carrier 110 is fixed to the knuckle of the vehicle body through mounting bolts (not shown), and the caliper housing 120 is slidably coupled to the both ends through a guide rod (not shown). In addition, a pair of pad plates 111 and 112 are slidably mounted in the center of the carrier 110 with a predetermined distance therebetween.

The pair of pad plates 111 and 112 are disposed so as to be in contact with the piston 121 to be described later and include an inner pad plate 111 having a friction pad 113 attached to the inner surface thereof, And an outer pad plate 112 to which a friction pad 113 is attached. At this time, the disk D is formed in a disk shape rotating together with a wheel (not shown) of an automobile, and a part of the disk D is rotated while being inserted between the pair of pad plates 111 and 112.

The caliper housing 120 is slidably mounted to the carrier 110. More specifically, the caliper housing 120 includes a fingering block 122 for operating the outer pad plate 112 and a cylinder 123 provided with a piston 121 to be slidable by the braking hydraulic pressure. The fingering member 122 and the cylinder 123 are integrally formed. At this time, the hydraulic duct 129 is formed at one end of the caliper housing 120 to receive the braking hydraulic pressure from the cylinder 123.

The fingering member 122 is formed to bend downward from the front portion of the caliper housing 120 so as to surround the outer pad plate 112 from the outside. As the caliper housing 120 is slid from the carrier 110 and moved in the right direction due to the reaction force of the piston 121 during the braking operation, the outer pad plate 112 The disc D is pushed toward the disc D so as to press the disc D.

The cylinder 123 is formed on the rear side of the caliper housing 120 to transmit the braking hydraulic pressure formed in the master cylinder (not shown) through the hydraulic duct 129, and the piston 121 is installed to move back and forth . That is, the piston 121 provided in the cylinder 123 moves back and forth in the cylinder 123 by the braking oil pressure.

The piston 121 is inserted into the cylinder 123 so as to be slidable in a cylindrical shape having a cup shape inside. The piston 121 presses the inner pad plate 111 toward the disc D by the braking hydraulic pressure. When the hydraulic pressure for braking is applied to the inside of the cylinder 123, the piston 121 is advanced to the inner pad plate 111 side to press the inner pad plate 111, and the caliper housing 120 is moved to the piston 121 so that the fingering member 122 presses the outer pad plate 112 toward the disc D to perform braking.

A sub piston 140, which will be described later, is inserted and coupled to the inner center portion of the piston 121. At this time, the piston 121 is coupled with the sub-piston 140 so as to move together with the sub-piston 140 when the piston 121 is moved by the braking oil pressure. The structure of the coupling between the piston 121 and the sub- I will explain.

Between the outer surface of the piston 121 and the inner surface of the cylinder 123, a sealing member 124 for preventing the leakage of oil is provided. The sealing member 124 serves to prevent the leakage of the brake oil flowing into the cylinder 123 and return the piston 121 to its original position upon release of the braking action.

The electric disk brake 100 is provided with a parking device that is supplied with a separate hydraulic pressure and operates according to the application of power. This parking apparatus is provided with a sub cylinder 130 installed in a cylinder 123, a parking piston 140 installed to be able to move forward and backward to the sub cylinder 130, and a sub cylinder 130 to supply a separate braking hydraulic pressure A housing 150 which is coupled to the caliper housing 120 and has a predetermined space formed therein and a housing 150 which is disposed in the sub cylinder 130 And a picking driver 170 for pressing and releasing the pressure.

The sub cylinder 130 has a cylindrical shape whose one end is opened, and is installed on the rear wall of the cylinder 123. A through hole 135 is formed in the rear portion of the sub cylinder 130. The through holes 135 are formed at positions corresponding to the through holes 125 formed in the rear portion of the cylinder 123 and are connected to each other in a straight line. The through holes 125 and 135 are communicated with the communication holes 155 formed in the housing 150 to be described later so that the oil is supplied to the through holes 125 and 135. The through holes 125 and 135 and the communication hole 155 are connected in a straight line, And the inside thereof is formed as a pressurizing chamber S. The inside of the sub cylinder 130 is partitioned from the cylinder 123 by a parking piston 140 installed on the sub cylinder 130.

The parking piston 140 is inserted into the sub cylinder 130 so as to be slidable in a cylindrical shape having a cup shape inside. Also, the parking piston 140 is provided to move together with the piston 121 as described above. According to the drawings, protrusions 141 penetrating the piston 121 are provided at the tip of the parking piston 140. At this time, a clip 142 is installed on the protrusion 141 exposed through the piston 121 so that the piston 121 and the parking piston 140 are not separated from each other. The protrusion 141 is formed in the parking piston 140 and is coupled to the piston 121 through the piston 121. The protrusion 141 is formed in the piston 121 to prevent the parking piston 140 from being engaged with the piston 121. [ As shown in FIG. Between the outer surface of the parking piston 140 and the inner surface of the sub cylinder 130, a sealing member 134 for preventing leakage of oil is provided. The sealing member 134 serves to prevent leakage of brake oil introduced into the sub-cylinder 130 and return the parking piston 140 to its original position when the braking action is released.

The housing 150 is installed on the rear outside of the caliper housing 120 and has a predetermined accommodation space therein. The housing 150 is provided with a communication hole 155 communicating with the through holes 135 and 125 passing through the sub cylinder 130 and the rear portion of the cylinder 123 and a communication hole 155 communicating with the communication hole 155 and the parking reservoir 160 The oil passage 156 is formed. At this time, the communication holes 155 are formed at positions corresponding to the through holes 125 and 135 and are connected in a straight line. As described above, the through holes 125 and 135 and the communication hole 155 are formed in the pressurizing chamber S inside thereof. The oil passage 156 is formed in the wall of the housing 150 and connected to the communication hole 155 and the parking reservoir 160. Thus, the oil for parking brake is supplied into the sub-cylinder 130 through the oil passage 156 and the pressurizing chamber S. [

The parking reservoir 160 for storing a separate oil for parking brake may be coupled to the outside of the housing 150 or may be coupled to the caliper housing 120 and connected to the oil passage 156.

The parking driving part 170 includes a plunger 171 installed in the housing 150 so as to be movable forward and backward and a rod 172 mounted on the plunger 171 and moving together with the plunger 171 to press the pressurizing chamber S, And a coil assembly 175 installed to surround the outer side of the plunger 171 and moving the plunger 171 forward and backward according to the application of power.

The plunger 171 is movably disposed within the bobbin 176 of the coil assembly 175 to be described later, and a through hole is formed at the center thereof.

The rod 172 has a predetermined length and is press-fitted into the through-hole formed in the plunger 171. The rod 172 moves together with the plunger 172 to pressurize the pressurizing chamber S. [ Thus, the end of the rod 172 is disposed in the pressurizing chamber S so as not to close the oil passage 156 before the operation. On the other hand, when the rod 172 presses the pressure chamber S, the hydraulic pressure is amplified along the principle of Pascal to provide sufficient pressure to the parking piston 140 in the sub-cylinder 130.

The coil assembly 175 includes a cylindrical bobbin 176 and a coil 178 wound around the permanent magnet 177 and the permanent magnet 177 provided on the outer periphery of the bobbin 176.

The bobbin 176 has a center through which the plunger 171 can move forward and backward, and a plurality of mounting portions 176a, 176b, and 176c are formed on the outer circumference of the bobbin 176 in the longitudinal direction. Such a bobbin 176 can be manufactured through an injection molding process with a plastic material. The permanent magnet 177 is provided on the mounting portion 176b provided at the outer periphery of the bobbin 176 and the coil 178 is wound around the mounting portions 176a and 176c formed on both sides of the outer periphery.

The permanent magnet 177 is installed to form a first magnetic field A from the inner center to the outer center of the bobbin 176. That is, the permanent magnet 177 is disposed such that the N pole is directed to the inside of the bobbin 176 and the S pole is directed to the outside of the bobbin 176. Accordingly, the first magnetic field A is formed in the N pole to the S pole direction in accordance with the characteristics of the permanent magnet 177. [ That is, the first magnetic field A is formed symmetrically with respect to the permanent magnet 177 on both sides. Therefore, the plunger 171 is kept in a state of being positioned at the rear portion of the housing 150 by the first magnetic field A before the parking driving portion 170 is operated.

The plunger 171 is moved by a power source applied to the coil 178. For example, by a second magnetic field (B ', B ") generated by a positive (+) or negative (-) power source applied to the coil 178. Depending on the power applied to the coil 178 The operation of moving the plunger 178 will be described below again.

A description will now be given of a state in which the electric disc brake 100 is operated by the braking hydraulic pressure.

3 is a view showing an operating state of an electric disc brake according to an embodiment of the present invention in accordance with a braking hydraulic pressure.

3, when the braking hydraulic pressure formed in the master cylinder (not shown) is transmitted into the cylinder 123 through the hydraulic duct 129, the piston 121 advances and the inner pad plate (see 111 in FIG. 1) . At this time, the parking piston 140 coupled with the piston 121 moves together. When the parking piston 140 moves, the sub-cylinder 130 is connected to the parking reservoir 160, and the sub-cylinder 130 is parked in accordance with the volume change in the sub-cylinder 130 as the parking piston 140 moves. The oil flows between the reservoir 160 and the reservoir 160 so that the braking operation can be performed smoothly.

Next, a state in which the parking brake force is generated through the parking brake device provided on the electric disk brake according to one aspect of the present invention will be described with reference to FIG. 4 to FIG.

2, the plunger 171 is positioned in a rear portion of the housing 150 by the first magnetic field A of the permanent magnet 177 in a state in which the power is off, . Accordingly, when a positive power is applied to the coil 178, a second magnetic field B 'is formed between the coil 178 and the permanent magnet 177 (see FIG. 4). The second magnetic field B 'is formed to flow clockwise as shown. As a result, the plunger 171 is advanced to the left as shown in Fig. At this time, the rod 172 coupled to the plunger 171 moves together with the plunger 171 and pressurizes the pressurizing chamber S, so that the amplified hydraulic pressure flows into the sub-cylinder 130 to pressurize the parking piston 140 do. That is, the parking piston 140 is pressed together with the piston 121 to bring the inner pad plate 111 into close contact with the disk D side.

When the parking brake is completed according to the movement of the plunger 171 as described above, the power applied to the coil 178 is turned off. 6, when the power is turned off in a state where the plunger 171 is moved to the front portion of the housing 150, that is, when the parking brake is completed, the plunger 171 is rotated by the first magnetic field generated from the permanent magnet 177 A in the front portion of the housing 150. The oil passage 156 connected to the parking reservoir 160 is closed by the rod 172. Accordingly, even when the power is turned off, the plunger 171 is maintained in the advanced state, so that the plunger 171 can function as a continuous parking brake.

7 is a view illustrating a state in which the parking operation is released through a parking apparatus provided in an electric disk brake according to an embodiment of the present invention.

7, when a negative power is applied to the coil 178 while the parking brake is completed, that is, when the power is off, a second magnetic field (not shown) is applied between the coil 178 and the permanent magnet 177, The second magnetic field B "flows in a direction opposite to that when the positive (+) power source is applied. That is, the second magnetic field B "flows in a counterclockwise direction when negative power is applied to the coil 178. Thus, the plunger 171 retracts to the right and the rod 172 The parking reservoir 160 and the sub cylinder 130 are communicated with each other through the oil passage 156. The oil in the sub cylinder 130 is returned to the parking reservoir 160 and the piston 121, When the negative power applied to the coil 178 is turned off after the completion of the parking brake release, the plunger 171 is returned to its original position And is held in a state of being located at the rear portion of the housing 150, as shown in Fig.

Meanwhile, as described above, the operation of applying or cutting off the power to the coil 178 can be operated through a parking switch (not shown). That is, the parking switch is provided in an off state before the parking brake. When the parking switch is pressed once for parking, the power is turned on and positive power is applied to the coil 178, When the switch is pressed, the power is turned off. In this state, when the parking brake is released to release the parking brake, the power is turned on and the negative power is applied to the coil 178. When the parking switch is pressed again, the power can be turned off . The structure of applying or cutting off the positive or negative power supply to the coil 178 through the on / off of the parking switch is a structure in which the positive power source and negative And a parking switch for applying or disconnecting a negative (-) power source.

As a result, the electric disc brake 100 according to one aspect of the present invention provides a solenoid type structure that operates according to the power on / off and a separate braking hydraulic pressure to generate the parking braking force It is possible to remarkably reduce the operating noise compared to the existing motor and gear connection structure and to simplify the configuration and to reduce the cost due to the reduction in the number of components.

While the present invention has been particularly shown and described with reference to exemplary embodiments thereof, it is to be understood that the invention is not limited to the disclosed exemplary embodiments. It will be understood that various modifications and changes may be made without departing from the scope of the appended claims.

100: electric disc brake 110: carrier
120: caliper housing 121: piston
123: cylinder 130: sub cylinder
140: parking piston 150: housing
155: communicating hole 156: oil passage
160: parking reservoir 170: parking driving part
171: plunger 172: rod
175: Coil assembly 176: Bobbin
177: permanent magnet 178: coil
A: first magnetic field B ', B ": second magnetic field
D: Disc S: Pressure chamber

Claims (7)

And a caliper housing provided with a carrier provided with a pair of pad plates so as to be movable forward and backward and a cylinder slidably mounted on the carrier and provided with a cylinder in which a cup- As a result,
A sub-cylinder installed in the cylinder to receive a separate braking hydraulic pressure for parking brake;
A parking piston coupled to the piston and installed to be movable forward and backward to the sub-cylinder;
A parking reservoir in which oil is stored to supply braking hydraulic pressure to the sub cylinder;
A communication hole which is coupled to the caliper housing and communicates with the through-hole passing through the sub-cylinder and the rear portion of the cylinder, and a housing having an oil flow path connecting the communication hole and the parking reservoir; And
And a parking driving part which is provided in the housing and moves forward and backward in response to power application and presses and releases the inside of the sub cylinder. The method according to claim 1,
The through-hole and the communication hole are connected in a straight line, and the inside thereof is formed as a pressurizing chamber,
The parking-
A plunger movably installed in the housing;
A rod installed on the plunger and moving together with the plunger to press the pressurizing chamber; And
And a coil assembly installed to surround the outside of the plunger and moving the plunger forward and backward in response to application of power. 3. The method of claim 2,
The coil assembly includes:
A cylindrical bobbin in which the plunger is arranged so as to be movable forward and backward and a plurality of mounting portions are defined in the outer periphery in the longitudinal direction;
A permanent magnet installed at a mounting portion provided at the center of the outer periphery of the bobbin; And
And a coil wound around a mounting portion formed on both sides of the outer periphery of the bobbin with the permanent magnet interposed therebetween. The method of claim 3,
Wherein the permanent magnet is installed such that a first magnetic field is formed from an inner center to an outer center of the bobbin. 5. The method of claim 4,
Wherein the plunger is positioned and held at either end of both ends of the housing by the first magnetic field. The method of claim 3,
The plunger is moved by a second magnetic field generated by a positive (+) power source or a negative (-) power source applied to the coil, and when the power source applied to the coil is interrupted, the plunger is moved to one end or the other end An electric disc brake in which the position is maintained. The method according to claim 1,
Wherein a front end portion of the parking piston has a protrusion penetrating through the piston to be in contact with the piston,
And the protrusion is provided with a clip so that the piston and the parking piston are not separated from each other.

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