Brake actuator and brake device including same

Abstract

Disclosed herein are a brake actuator and a brake device including the same. The brake actuator includes: a housing; the first motor is mounted in the shell; a transmission gear rotatably mounted in the housing and connected to the first motor; a first parking member configured to rotate together with the transfer gear; a second motor spaced apart from the first motor; and a second parking member mounted to be rotatable and linearly movable in the housing and configured to selectively restrict rotation of the first parking member by operation of the second motor. The brake actuator and the brake device according to the present disclosure can prevent damage to the second output shaft by distributing a reaction force generated between the extension portion and the latch during parking brake through the support member.

Description

Technical Field

[0001] Exemplary embodiments of the present disclosure relate to a brake actuator and a braking device including the same, and more particularly, to a brake actuator capable of ensuring stable parking brake performance and a braking device including the same. Background Art

[0002] A vehicle braking device is generally used to brake a vehicle by using a driving force to push a piston so that a pad is brought into close contact with a disk, thereby using a frictional force between the brake pad and the brake disk.

[0003] Among them, an electro mechanical brake (EMB) generates a braking force by directly mounting a motor-driven actuator to a brake caliper without using hydraulic pressure and pressing a piston through mechanisms such as gears and screws. Such an EMB can perform active braking and wheel-specific independent braking, enabling additional functions such as an antilock brake system (ABS), an electronic stability controller (ESC), a traction control system (TCS), and an autonomous emergency braking (AEB) system, as well as typical primary braking. Since there is no delay in hydraulic transmission, the EMB can also achieve higher performance.

[0004] Conventional EMBs ensure quick response and high efficiency of the piston through ball screws. However, due to their structural characteristics, these ball screws do not allow self-locking that restricts their own rotation. Therefore, if the power supply to the motor is interrupted, the braking force can be arbitrarily released by the repulsive force between the brake pad and the piston.

[0005] The related art of the present disclosure is disclosed in Korean Patent Application Publication No. 10-2010-0098846 (published on September 10, 2010, titled "DISC BRAKE WITH PARKING FUNCTION"). Summary of the Invention

[0006] The present Summary of the Invention is provided to introduce a selection of concepts that are further described below in the Detailed Description. The Summary of the Invention is not intended to identify key features or essential features of the claimed subject matter, nor is it intended to be used to assist in determining the scope of the claimed subject matter.

[0007] Various embodiments relate to a brake actuator capable of ensuring stable parking brake performance and a braking device including the same.

[0008] In one embodiment, the brake actuator includes: a housing; a first motor mounted in the housing; a transmission gear rotatably mounted in the housing and connected to the first motor; a first parking member configured to rotate with the transmission gear; a second motor spaced apart from the first motor; and a second parking member mounted to be rotatable and linearly movable in the housing and configured to selectively restrict the rotation of the first parking member by operation of the second motor.

[0009] The first parking member may include: a first parking body connected to a first output shaft of the first motor; and a plurality of extension portions extending from the first parking body and arranged along a circumferential surface of the first parking body.

[0010] Each extension portion may extend obliquely with respect to a radial direction of the first parking body.

[0011] The second parking member may include: a second parking body; a guide rail formed through the second parking body, into which a second output shaft of the second motor is inserted; and a latch that extends from the second parking body and inserts between an associated pair of adjacent extension portions when the second parking body rotates in a first rotation direction. The second parking body may rotate at the same angular velocity as the second output shaft, and when the latch inserts between an associated pair of adjacent extension portions, the second parking body may linearly move in a first direction.

[0012] A longitudinal direction of the guide rail may extend in a direction parallel to the first direction.

[0013] A width of the guide rail perpendicular to the first direction may be smaller than a width of the second output shaft perpendicular to its longitudinal direction.

[0014] The second parking member may further include: a first return member connected to the second parking body and configured to press the second parking body in a second rotation direction opposite to the first rotation direction; and a second return member connected to the second parking body and configured to press the second parking body in a second direction opposite to the first direction.

[0015] The first return member may be configured to be elastically deformable, and both ends of the first return member may be connected to the second motor and the second parking body, respectively.

[0016] The first return member may be a torsion spring.

[0017] The second return member may be configured to be elastically deformable, and both ends of the second return member may be connected to the second output shaft and the second parking body, respectively.

[0018] The second reset member can be a compression spring.

[0019] The second parking member can further include a support member configured to limit the movement range of the second parking body relative to the first direction.

[0020] The support member can include: a first stopper extending from the second parking body; and a second stopper provided to face the first stopper and configured to contact the first stopper when the second parking body moves in the first direction beyond a set distance.

[0021] The second stopper can extend from the housing.

[0022] The first parking body can be mounted to be movable in the longitudinal direction of the first output shaft. When the reaction force between an associated one of the extension portions in the extension portion and the latch increases beyond a set magnitude, the first parking body can move in a departure direction parallel to the longitudinal direction of the first output shaft.

[0023] The extension portion can have a side surface inclined with respect to the longitudinal direction of the first output shaft.

[0024] The brake actuator can further include a reset member configured to move the first parking member in a direction opposite to the departure direction.

[0025] The reset member can be configured to be elastically deformable in a direction parallel to the longitudinal direction of the first output shaft, and both ends of the reset member can contact the first parking body and the transmission gear respectively.

[0026] The reset member can be a compression spring.

[0027] In another embodiment, the braking device includes a caliper body, a piston unit movably mounted on the caliper body, and a brake actuator connected to the piston unit and configured to move the piston unit. The brake actuator includes: a housing; a first motor mounted in the housing; a transmission gear rotatably mounted in the housing and connected to the first motor; a first parking member configured to rotate together with the transmission gear; a second motor spaced apart from the first motor; and a second parking member mounted to be rotatable and linearly movable in the housing and configured to selectively limit the rotation of the first parking member by the operation of the second motor.

[0028] As is obvious from the above description, even if the operation of the first motor is released during the parking brake by the first parking member and the second parking member, the brake actuator and the braking device according to the present disclosure can maintain the parking braking force.

[0029] The brake actuator and brake device according to the present disclosure can return the second parking body to its initial position without driving the second motor through the first return member and the second return member, so that the operation of the second parking body can be controlled only by the on / off (ON / OFF) control of the second motor.

[0030] The brake actuator and brake device according to the present disclosure can prevent damage to the second output shaft by distributing the reaction force generated between the extension part and the latch during parking braking through the support member.

[0031] When the braking force cannot be smoothly released due to damage or failure of the first parking member and the second parking member, the brake actuator and brake device according to the present disclosure can prevent the vehicle from losing its driving ability by forcibly releasing the braking force through the inclined structure of the extension part and the reset member. BRIEF DESCRIPTION OF THE DRAWINGS

[0032] Figure 1 is a perspective view schematically showing the configuration of a brake device according to an embodiment of the present disclosure.

[0033] Figure 2 is a cross-sectional view schematically showing the configuration of a brake device according to an embodiment of the present disclosure.

[0034] Figure 3 is a perspective view schematically showing the configuration of a brake actuator according to an embodiment of the present disclosure.

[0035] Figure 4 is a front view schematically showing the configuration of a brake actuator according to an embodiment of the present disclosure.

[0036] Figure 5 is a perspective view schematically showing the configuration of a first parking member and a second parking member according to an embodiment of the present disclosure.

[0037] Figure 6 is a front view schematically showing the configuration of a first parking member and a second parking member according to an embodiment of the present disclosure.

[0038] Figure 7 is an enlarged view schematically showing the configuration of a guide rail according to an embodiment of the present disclosure.

[0039] Figure 8 is a view schematically showing the installation state of a reset member according to an embodiment of the present disclosure.

[0040] Figures 9 to 11 is a view schematically showing the process of generating a parking braking force.

[0041] Figures 12 to 14It is a view schematically showing the process of releasing the parking braking force.

[0042] Figure 15 and Figure 16 It is a view schematically showing the process of forcibly releasing the parking braking force. Detailed implementation manners

[0043] Hereinafter, exemplary embodiments of the present disclosure will be described with reference to the accompanying drawings.

[0044] It should be considered that, for the sake of clarity and convenience of description, the thickness of each line or the size of each component in the accompanying drawings may be shown enlarged. In addition, the terms used herein are terms defined in consideration of the functions of the present disclosure, and these terms may be changed according to the intention or practice of the user or operator. Therefore, these terms should be defined based on the entire disclosure set forth herein.

[0045] In this specification, it will be understood that when an element is referred to as being "connected (or joined)" to another element, the element may be "directly connected (or joined)" to the other element, or the element may be "indirectly connected (or joined)" to other elements, with other elements intervening therebetween. In this specification, it will be understood that when a component is referred to as "including (or containing)" any component, the component does not exclude other components, but may also include (or contain) other components, unless otherwise stated.

[0046] Throughout this specification, the same reference numerals may refer to the same components. Even if the same or similar reference numerals are not mentioned or described in a specific drawing, they may be described based on other drawings. In addition, even if there are elements in a specific drawing that are not labeled with reference numerals, the element may be described based on other drawings. Moreover, the number, shape, size, relative differences, etc. of the detailed components shown in the drawings herein are set for ease of understanding, and may be implemented in various forms without limiting its embodiments.

[0047] Figure 1 It is a perspective view schematically showing the configuration of a braking device according to an embodiment of the present disclosure. Figure 2 It is a cross-sectional view schematically showing the configuration of a braking device according to an embodiment of the present disclosure.

[0048] Referring to Figure 1 and Figure 2 , the braking device denoted by reference numeral 1 according to the present embodiment includes a caliper body 10, a piston unit 20, and a brake actuator 30.

[0049] The caliper body 10 may define the schematic appearance of the braking device and support the piston unit 20 and the brake actuator 30 as a whole.

[0050] The caliper body 10 according to this embodiment may include a bridge member 11, finger members 12, and a cylinder 13.

[0051] The bridge member 11 may define the central appearance of the caliper body 10 and support the finger members 12 and the cylinder 13. The bridge member 11 may have a lower surface facing the circumferential surface of the brake disc D, and this lower surface is spaced apart from the circumferential surface of the brake disc D by a predetermined distance. The bridge member 11 may have both sides extending in opposite directions along a direction parallel to the central axis of the brake disc D ( Figure 1 the X-axis direction in Figure 1 and Figure 2 shown). The bridge member 11 is not limited to having the

[0052] shape shown in

[0053] and can be designed and changed into various shapes.

[0052] A pair of brake pads P may be arranged on the lower side of the bridge member 11. The pair of brake pads P may be spaced apart from each other along the central axis of the brake disc D. The pair of brake pads P may face each other with the brake disc D therebetween. The pair of brake pads P may be supported on the bracket 2 or the bridge member 11 so as to be slidable in a direction parallel to the central axis of the brake disc D. Friction pads made of a material having a high coefficient of friction (such as rubber) may be attached to one surface of each brake pad P facing the brake disc D.

[0053] The bridge member 11 may be movably connected to the bracket 2 fixed to a knuckle (not shown), etc. via a guide rod 11a. During vehicle braking, the bridge member 11 may slide in a direction parallel to the central axis of the brake disc D by the reaction force generated between the piston unit 20 and the associated brake pad P.

[0054] The finger member 12 may extend downward from one side of the bridge member 11. The finger member 12 may be integrally connected to the bridge member 11 by welding, pressing, bending, etc. The finger member 12 may be provided to face one of the pair of brake pads P. The finger member 12 may press one of the pair of brake pads P against the brake disc D or release one of the pair of brake pads P from the brake disc D by sliding the bridge member 11.

[0055] The cylinder 13 may extend downward from the other side of the bridge member 11. The cylinder 13 may have a hollow cylindrical shape that is open on one side. The central axis of the cylinder 13 may be parallel to the central axis of the brake disc D. The open side of the cylinder 13 may be provided to face the remaining one of the pair of brake pads P.

[0056] The piston unit 20 can be movably mounted on the caliper body 10. Depending on the moving direction of the piston unit 20, the piston unit 20 can contact or separate from the remaining one of the pair of brake pads (P). When the piston unit 20 contacts the associated brake pad P, the piston unit 20 can press the brake pad P toward the brake disc D so that the brake pad P is in close contact with the brake disc D to apply a braking force to the vehicle. The piston unit 20 can release the pressing force applied to the brake pad P when separating from the brake pad P, so that the brake pad P separates from the brake disc D to release the braking force applied to the vehicle.

[0057] The piston unit 20 can include a piston 21, a bolt screw 22, and a nut screw 23.

[0058] The piston 21 can have a cup shape that is open on one side. The closed side of the piston 21 can point to the brake pad P that is set to face the cylinder 13. The open side of the piston 21 can point to the inner space of the cylinder 13. The piston 21 can have an outer surface that is slidably supported on the inner surface of the cylinder 13. Alternatively, the outer surface of the piston 21 can also be spaced apart from the inner surface of the cylinder 13 by a predetermined distance to form a gap therebetween.

[0059] The piston 21 can move back and forth in a direction parallel to the central axis of the cylinder 13 (in a direction parallel to the X-axis in Figure 1 ). When the piston 21 moves forward, it can protrude to the outside of the cylinder 13 and press the brake pad P that is set to face the cylinder 13 toward the brake disc D. In this case, the bridge member 11 can move in a direction opposite to the moving direction of the piston 21 by the reaction force generated between the piston 21 and the brake pad P. When the piston 21 moves backward, it can release the pressing force applied to the brake pad P and separate the brake pad P from the brake disc D.

[0060] The bolt screw 22 can be disposed inside the cylinder 13 and can be rotated by the driving force received from the brake actuator 30.

[0061] As an example, the bolt screw 22 can be in the form of a rod having a substantially circular cross-section. The bolt screw 22 can be disposed inside the cylinder 13, and the central axis of the bolt screw can be coaxially positioned with the central axis of the cylinder 13. The bolt screw 22 can have one end facing the inner end surface of the piston 21, and this end is spaced apart from the inner end surface of the piston 21 by a predetermined distance. The bolt screw 22 can have the other end protruding to the outside of the caliper body 10 through the closed side of the cylinder 13. When the brake actuator 30 is operated, the bolt screw 22 can rotate clockwise or counterclockwise about its central axis.

[0062] The bolt screw 22 may have a groove formed on its outer circumferential surface, and a circumference of the spherical rolling element is disposed in the groove. The groove may extend helically in the longitudinal direction of the bolt screw 22 to provide a circulation path for the rolling element.

[0063] The nut screw 23 may be disposed inside the cylinder 13 and may be connected to the bolt screw 22. The nut screw 23 may linearly reciprocate in a direction parallel to the longitudinal direction of the bolt screw 22 in conjunction with the rotation of the bolt screw 22 within the cylinder 13. The nut screw 23 may press the piston 21 toward the brake pad P or release the piston 21 from the brake pad P according to its moving direction.

[0064] As an example, the nut screw 23 may have a hollow cylindrical shape. The nut screw 23 may have an inner circumferential surface facing the outer circumferential surface of the bolt screw 22, and the inner circumferential surface is spaced apart from the outer circumferential surface of the bolt screw 22 by a predetermined distance. The nut screw 23 may have a groove formed on its inner circumferential surface, and another circumference of the spherical rolling element is disposed in the groove. The groove may extend helically in the longitudinal direction of the nut screw 23 to provide a circulation path for the rolling element.

[0065] The nut screw 23 may receive the rotational force of the bolt screw 22 via the rolling element. When the bolt screw 22 rotates, the nut screw 23 may move back and forth along the longitudinal direction of the bolt screw 22 by the circulating motion of the rolling element.

[0066] When the nut screw 23 moves forward, the nut screw 23 may contact the inner surface of the piston 21 to press the piston 21 toward the brake disc D. When the nut screw 23 moves backward, the nut screw 23 may separate from the inner surface of the piston 21 to release the pressing force applied to the piston 21.

[0067] The brake actuator 30 may be connected to the piston unit 20 and may move the piston unit 20. In other words, the brake actuator 30 may function as a component that generates a driving force for applying a braking force to the vehicle or releasing a braking force from the vehicle and transmits the generated driving force to the piston unit 20.

[0068] Figure 3 is a perspective view schematically showing the configuration of a brake actuator according to an embodiment of the present disclosure. Figure 4 is a front view schematically showing the configuration of a brake actuator according to an embodiment of the present disclosure.

[0069] Reference Figure 3 and Figure 4 , the brake actuator 30 according to this embodiment includes a housing 100, a first motor 200, a transmission gear 300, a first parking member 400, a second motor 500, and a second parking member 600.

[0070] The housing 100 can be fixed to the caliper body 10 and can support the first motor 200, the transmission gear 300, the first parking member 400, the second motor 500, and the second parking member 600 as a whole.

[0071] The housing 100 can include a housing body 110 and a housing cover 120.

[0072] The housing body 110 can have a hollow cylindrical shape that is open on one side. The closed side of the housing body 110 can be set to face the rear of the cylinder 13. The housing body 110 can be fixed to the rear of the cylinder 13 by various types of coupling methods (such as bolt connection, welding, and assembly). The housing body 110 is not limited to having Figure 3 and Figure 4 the shape shown in, and can be designed and changed into various shapes.

[0073] The housing cover 120 can be set to face the housing body 110 and can enclose the internal space of the housing body 110. The housing cover 120 can have a substantially plate-like shape and can be set to face the open side of the housing body 110. The housing cover 120 can be fixed to the open side of the housing body 110 by various types of coupling methods (such as bolt connection, welding, and assembly). The cross-sectional shape of the housing cover 120 can correspond to the cross-sectional shape of the housing body 110.

[0074] The first motor 200 is installed in the housing 100 and generates a rotational force to move the piston unit 20. As an example, the first motor 200 can be exemplified as various types of electric motors that can rotate the first output shaft 210 by receiving power from the outside. The first motor 200 can be fixed to the outside of the housing body 110 by various types of coupling methods (such as bolt connection, welding, and assembly). The first output shaft 210 can project into its internal space through the housing body 110. The first output shaft 210 can be set such that its longitudinal direction is parallel to the longitudinal direction of the bolt screw 22 in the cylinder 13, for example, Figure 3 the X-axis direction in. The first motor 200 can be electrically connected to the vehicle's battery or the like to receive power from it.

[0075] The transmission gear 300 is rotatably installed in the housing 100. The transmission gear 300 is connected to the first motor 200 and rotates by combining the rotational force generated by the first motor 200. The transmission gear 300 can be used as a component that transmits the rotational force generated by the first motor 200 to the piston unit 20.

[0076] The transmission gear 300 can include a first transmission gear 310, a second transmission gear 320, and a third transmission gear 330.

[0077] The first transmission gear 310 can be connected to the first output shaft 210 of the first motor 200. As an example, the first transmission gear 310 can be a hollow helical gear or a spur gear, with teeth formed on its outer peripheral surface. The central axis of the first transmission gear 310 can be set to be coaxial with the central axis of the first output shaft 210 of the first motor 200. The first transmission gear 310 can have an inner peripheral surface with a spline connected to the outer peripheral surface of the first output shaft 210. Thus, when the first motor 200 operates, the first transmission gear 310 can rotate at the same angular velocity as the first output shaft 210.

[0078] The second transmission gear 320 can mesh with the first transmission gear 310 and can rotate together with the rotation of the first transmission gear 310. As an example, the second transmission gear 320 can be a hollow helical gear or a spur gear, with teeth formed on its outer peripheral surface. The central axis of the second transmission gear 320 can be set to be parallel to the central axis of the first transmission gear 310. The second transmission gear 320 can be supported by a separate shaft (not shown) or the like to be rotatable about its central axis within the housing 100. The second transmission gear 320 can have an outer peripheral surface that meshes with the outer peripheral surface of the first transmission gear 310. When the first transmission gear 310 rotates, the second transmission gear 320 can rotate in a direction opposite to that of the first transmission gear 310. The second transmission gear 320 can have a larger diameter than the first transmission gear 310. Thus, the second transmission gear 320 can increase the magnitude of the rotational force transmitted from the first transmission gear 310.

[0079] The third transmission gear 330 can mesh with the second transmission gear 320 and can rotate together with the rotation of the second transmission gear 320. The third transmission gear 330 can be used as a component that finally transmits the rotational force generated by the first motor 200 to the piston unit 20. As an example, the third transmission gear 330 can be a hollow helical gear or a spur gear, with teeth formed on its outer peripheral surface. The central axis of the third transmission gear 330 can be set parallel to the central axis of the second transmission gear 320. The central axis of the third transmission gear 330 can be coaxially positioned with the central axis of the bolt screw 22 of the piston unit 20. The third transmission gear 330 can have an outer peripheral surface that meshes with the outer peripheral surface of the second transmission gear 320. When the second transmission gear 320 rotates, the third transmission gear 330 can rotate about its central axis in a direction opposite to that of the second transmission gear 320. The rear end of the bolt screw 22 protruding from the rear of the cylinder 13 can be inserted into the center of the third transmission gear 330. The bolt screw 22 can have an outer peripheral surface with a spline connection to the inner peripheral surface of the third transmission gear 330. Thus, when the third transmission gear 330 rotates, the bolt screw 22 can rotate with the third transmission gear 330 to move the nut screw 23 back and forth. The third transmission gear 330 can have a larger diameter than the second transmission gear 320. Therefore, when the second transmission gear 320 rotates, the third transmission gear 330 can rotate at a lower angular velocity than the second transmission gear 320, and the third transmission gear 330 can amplify the magnitude of the rotational force transmitted to the piston unit 20.

[0080] When the first output shaft 210 rotates in the direction of brake application, the rotational force of the first output shaft 210 can be sequentially transmitted to the first transmission gear 310, the second transmission gear 320, the third transmission gear 330, and the bolt screw 220, and the nut screw 23 and the piston 21 can move forward to bring the brake pad P into close contact with the brake disc D.

[0081] When the first output shaft 210 rotates in the direction of brake release, the rotational force of the first output shaft 210 can be sequentially transmitted to the first transmission gear 310, the second transmission gear 320, the third transmission gear 330, and the bolt screw 220, and the nut screw 23 and the piston 21 can move backward to separate the brake pad P from the brake disc D.

[0082] The first parking member 400 can be used as a component that rotates together with the transmission gear 300 and holds the parking braking force together with the second parking member 600.

[0083] Figure 5 is a perspective view schematically showing the configurations of the first parking member and the second parking member according to an embodiment of the present disclosure. Figure 6is a front view schematically showing the configuration of a first parking member and a second parking member according to an embodiment of the present disclosure.

[0084] Reference Figures 1 to 6 , the first parking member 400 may include a first parking body 410 and an extension portion 420.

[0085] The first parking body 410 may be connected to the first output shaft 210 of the first motor 200. For example, the first parking body 410 may be in the form of a ring with a hollow formed at its center. The central axis of the first parking body 410 may be positioned coaxially with the central axis of the first output shaft 210. The first parking body 410 may have an inner circumferential surface with splines connected to the outer circumferential surface of the first output shaft 210. When the first output shaft 210 rotates, the first parking body 410 may rotate at the same angular velocity as the first output shaft 210 and the first transmission gear 310. Therefore, compared with when the first parking body 410 is connected to the second transmission gear 320 or the third transmission gear 330 (whose rotational force is multiplied by its gear ratio), the first parking body 410 may reduce the magnitude of the load applied to the second parking member 600. When the first output shaft 210 rotates, the first parking body 410 may rotate with the first output shaft 210 in the direction of brake application or in the direction of brake release.

[0086] The extension portion 420 may be used as a component that extends from the first parking body 410 and forms an interference structure with the second parking member 600. As an example, the extension portion 420 may protrude from the circumferential surface of the first parking body 410 to the outside of the first parking body 410. The extension portion 420 may be composed of a plurality of extension portions. The plurality of extension portions 420 may be arranged at set intervals along the circumferential surface of the first parking body 410 around the central axis of the first parking body 410. The distances between adjacent extension portions 420 may all be the same.

[0087] Each extension portion 420 may extend obliquely with respect to the radial direction of the first parking body 410. As an example, the extension portion 420 may be inclined at a set angle or may extend spirally in a bent shape from the circumferential surface of the first parking body 410 in the direction of brake release (i.e., in the Figure 6 clockwise direction in). Therefore, when the extension portion 420 is fastened to the second parking member 600, the extension portion 420 may allow the first parking body 410 to rotate in the direction of brake release, and at the same time may limit the rotation of the first parking body 410 in the direction of brake release.

[0088] The second motor 500 is installed in the housing 100 and generates a rotational force to rotate the second parking member 600. As an example, the second motor 500 can be exemplified as various types of electric motors that can rotate the second output shaft 510 by receiving power from the outside. The second motor 500 can be spaced apart from the first motor 200. The second motor 500 can be disposed inside the housing body 110, or alternatively, can be disposed outside the housing body 110. The second motor 500 can be fixed to the housing body 110 by various types of coupling methods (such as bolt connection, welding, and assembly). The second output shaft 510 can be disposed in the internal space of the housing body 110. The second output shaft 510 can be disposed such that its longitudinal direction is parallel to the longitudinal direction of the first output shaft 210. Alternatively, the second output shaft 510 can be disposed such that its longitudinal direction intersects the longitudinal direction of the first output shaft 210. The second motor 500 can be electrically connected to a battery of the vehicle or the like to receive power from the battery or the like.

[0089] The second parking member 600 can be installed to be rotatable and linearly movable in the housing 100. The second parking member 600 can be rotated and linearly moved by the operation of the second motor 500, and can selectively restrict the rotation of the first parking member 400. More specifically, the second parking member 600 can allow the first parking member 400 to rotate during normal driving of the vehicle, so that the main brake is smoothly performed by the first motor 200. In addition, the second parking member 600 can restrict the rotation of the first parking member 400 during the main brake of the vehicle, so that even if the operation of the first motor 200 stops, the piston unit 20 can be prevented from losing the parking braking force due to arbitrary separation from the brake pad P.

[0090] The second parking member 600 can include a second parking body 610, a guide rail 620, and a latch 630.

[0091] The second parking body 610 can define the schematic appearance of the second parking member 600 and can support the latch 630. The second parking body 610 can be connected to the second output shaft 510 via the guide rail 620. For example, the second parking body 610 can have a substantially rod-shaped shape.

[0092] The second parking body 610 can rotate in a first rotation direction and a second rotation direction opposite to the first rotation direction as the second output shaft 510 rotates. The rotation of the second parking body 610 in the first rotation direction can refer to the second parking body 610 rotating counterclockwise around Figure 6 the central axis of the second output shaft 510 therein, and the rotation of the second parking body 610 in the second rotation direction can refer to the second parking body 610 rotating clockwise around Figure 6 the central axis of the second output shaft 510 therein.

[0093] The second parking body 610 can linearly move in the first direction and the second direction by the reaction force acting between the extension part 420 and the latch 630. Here, the first direction may refer to the direction pointing to one end of the two ends of the second parking body 610 where the latch 630 is not formed and parallel to the longitudinal direction of the second parking body 610. In addition, the second direction may refer to the direction opposite to the first direction, which points to one end of the two ends of the second parking body 610 where the latch 630 is not formed and parallel to the longitudinal direction of the second parking body 610.

[0094] The guide rail 620 can be used as a component that transmits the rotational force of the second output shaft 510 to the second parking body 610 when the second output shaft 510 rotates, so as to rotate the second parking body 610 in the first rotational direction or the second rotational direction. In addition, the guide rail 620 can be used as a component that supports the movement of the second parking body 610 in the first direction and the second direction, so as to guide the linear movement of the second parking body 610.

[0095] Figure 7 is an enlarged view schematically showing the configuration of the guide rail according to an embodiment of the present disclosure.

[0096] Reference Figures 5 to 7 , the guide rail 620 can be formed by the second parking body 610. The second output shaft 510 of the second motor 500 can be inserted into the guide rail 620. The guide rail 620 can have two ends extending in the longitudinal direction of the second parking body 610. In other words, the longitudinal direction of the guide rail 620 can extend parallel to the first direction and the second direction.

[0097] The guide rail 620 can have a width w1 perpendicular to the first direction and smaller than one of the widths of the second output shaft 510 perpendicular to its longitudinal direction. For example, as Figure 7 shown, the width w1 of the guide rail 620 perpendicular to the first direction can be smaller than the width w2 of the second output shaft 510 parallel to the first direction. Therefore, when the second output shaft 510 rotates, the second parking body 610 can rotate at the same angular velocity as the second output shaft 510 while the second output shaft 510 does not rotate relative to the guide rail 620. The cross-sectional shape of the second output shaft 510 can be designed and changed into various shapes other than the circular shape, such as an elliptical shape, a polygonal shape, or an irregular shape.

[0098] The circumferential surface of the second output shaft 510 can be in slidable contact with the inner surface of the guide rail 620. Therefore, the second output shaft 510 can guide the second parking body 610 to move smoothly and linearly along a fixed path.

[0099] The latch 630 can extend from the second parking body 610. The latch 630 can restrict or permit the rotation of the extension part 420 according to the rotation direction of the second parking body 610.

[0100] As an example, the latch 630 can extend from one end of the second parking body 610 spaced apart from the guide rail 620 in a first direction. The longitudinal direction of the latch 630 can extend obliquely with respect to the first direction. The latch 630 can have one end pointing to the first parking member 400. When the second parking body 610 rotates in the first rotation direction, the latch 630 can be inserted between any associated pair of adjacent extension parts 420. In this case, the latch 630 can latch to the associated extension part 420 to restrict the rotation of the first parking body 410. When the second parking body 610 rotates in the second rotation direction, the latch 630 can be separated from the associated pair of adjacent extension parts 420. In this case, the latch 630 can be unlocked from the associated extension part 420 to permit the rotation of the first parking body 410.

[0101] The width of the latch 630 can gradually narrow towards one end thereof. Thus, when the second parking body 610 rotates in the first rotation direction, the latch 630 can be more easily inserted between any associated pair of adjacent extension parts 420.

[0102] When the latch 630 is inserted between an associated pair of adjacent extension parts 420, a reaction force can be generated between the latch 630 and the associated extension part 420 in a direction parallel to the first direction. This reaction force can permit the second parking body 610 to linearly move in the first direction.

[0103] The second parking member 600 can further include a first return member 640 and a second return member 650.

[0104] The first return member 640 can be connected to the second parking body 610 and can press the second parking body 610 in a second rotation direction opposite to the first rotation direction. The first return member 640 can be configured to be elastically deformable. The first return member 640 can be used as a component that rotates the second parking body 610 in the second rotation direction by its own elastic restoring force when the latch 630 is unlocked from the extension part 420. Thus, when the parking brake is released, the first return member 640 can return the second parking body 610 to its initial angle without driving the second motor 500, so that the two-way rotation of the second parking body 610 can be achieved only by the on / off control of the second motor 500.

[0105] As an example, the first return member 640 may be a torsion spring that stores or releases rotational force through elastic deformation. The central axis of the first return member 640 may be positioned coaxially with the central axis of the second output shaft 510. One end of the first return member 640 may be connected to the second parking body 610. The other end of the first return member 640 may be connected to the second motor 500. However, the connection position of the other end of the first return member 640 is not limited thereto, and various designs and changes can be made thereto. For example, the other end of the first return member 640 may be connected to a part that is fixed to the housing 100 etc. when the second parking body 610 rotates.

[0106] The first return member 640 may be mounted to be compressed or tensioned in the first rotational direction in a neutral state when the latch 630 is inserted into an associated pair of adjacent extensions 420. Thus, when the parking brake is released, the first return member 640 may unlock the latch 630 from the associated extension 420 by applying a rotational force to the second parking body 610 in the second rotational direction.

[0107] One end of the first return member 640 may be connected to the second parking body 610 so as to be slidable in a direction parallel to the first direction. In this case, the other end of the first return member 640 may be fixed to the second motor 500. Thus, the first return member 640 may apply a rotational force to the second parking body 610 in the second rotational direction and, at the same time, may not interfere with the linear movement of the second parking body 610. Alternatively, one end of the first return member 640 may be fixed to the second parking body 610, and the other end of the first return member 640 may be connected to the second motor 500 so as to be slidable in a direction parallel to the first direction.

[0108] The second return member 650 may be connected to the second parking body 610 and may press the second parking body 610 in a second direction opposite to the first direction. The second return member 650 may be configured to be elastically deformable. The second return member 650 may be used as a component that linearly moves the second parking body 610 in the second direction by its own elastic restoring force when the latch 630 is unlocked from the extension 420. Thus, when the parking brake is released, the second return member 650 may return the second parking body 610 that has moved in the first direction to its initial position without the need for a separate power element.

[0109] As an example, the second return member 650 can be a compression spring that is elastically deformable in its longitudinal direction. The second return member 650 can be arranged such that its longitudinal direction is parallel to the first direction. The second return member 650 can be inserted into the guide rail 620. The second return member 650 can have two ends that are in contact with the circumferential surface of the second output shaft 510 and the inner surface of the second parking body 610, respectively. When the second parking body 610 moves in the first direction, the second return member 650 can be longitudinally compressed to store elastic energy. When the latch 630 is unlocked from the extension portion 420, the second return member 650 can press the second parking body 610 against the second output shaft 510 in the second direction by the stored elastic energy and can move the second parking body 610 in the second direction.

[0110] The second parking member 600 can further include a support member 660.

[0111] The support member 660 can limit the range of linear movement of the second parking body 610 relative to the first direction. More specifically, the support member 660 can function as a component that, when the second parking body 610 moves in the first direction by a reaction force acting between the latch 630 and the extension portion 420 beyond a set distance, restricts the movement of the second parking body 610 by supporting the second parking body 610 in a direction opposite to the reaction force acting between the latch 630 and the extension portion 420. Therefore, the support member 660 can prevent damage to the second output shaft 510 by preventing the reaction force acting between the latch 630 and the extension portion 420 from being directly transmitted to the second output shaft 510.

[0112] The support member 660 can include a first stopper 661 and a second stopper 662.

[0113] The support member 660 can extend from the second parking body 610. As an example, the support member 660 can be in the form of a rod that extends in a direction intersecting the first direction and the second direction at a position spaced apart from the latch 630.

[0114] The second stopper 662 can be spaced apart from the second parking body 610 and can face the first stopper 661. When the second parking body 610 moves in the first direction beyond the set distance, the second stopper 662 can contact one surface of the first stopper 661. For example, the second stopper 662 can be in the form of a rod that extends from the inner surface of the housing 100 toward the interior space of the housing 100.

[0115] Figure 8 is a view schematically showing the installation state of the return member according to an embodiment of the present disclosure.

[0116] Reference Figure 8, the first parking body 410 can be installed to reciprocate in the longitudinal direction of the first output shaft 210. As an example, the first parking body 410 can have an inner circumferential surface that is splined to the outer circumferential surface of the first output shaft 210.

[0117] The side surface of the extension portion 420 can be inclined with respect to the longitudinal direction of the first output shaft 210. As an example, the cross-sectional area of the extension portion 420 gradually narrows as it points upward in Figure 8 it.

[0118] The side surface of the latch 630 can be parallel to the longitudinal direction of the first output shaft 210. Alternatively, the side surface of the latch 630 can be inclined with respect to the longitudinal direction of the first output shaft 210. In this case, the side surface of the latch 630 can be formed at an angle corresponding to the side inclination of the extension portion 420 so as to make surface contact with the side surface of the extension portion 420.

[0119] A part of the reaction force acting between the extension portion 420 and the latch 630 can be transmitted in a direction parallel to the longitudinal direction of the first output shaft 210 through the inclination angle of the side surface of the extension portion 420. In this case, when the reaction force acting between the extension portion 420 and the latch 630 increases beyond a set magnitude, the first parking body 410 can linearly move in a deviation direction parallel to the longitudinal direction of the first output shaft 210. When the first parking body 410 moves in the deviation direction, the extension portion 420 can be separated from the latch 630. As an example, the deviation direction can be the Figure 8 downward direction in it. Therefore, if the second parking body 610 does not rotate smoothly in the second rotation direction due to the extrusion between the extension portion 420 and the latch 630 or damage to the first return member 640, the extension portion 420 can be separated from the latch 630 by the forced rotation of the first output shaft 210.

[0120] The brake actuator 30 can further include a reset member 700.

[0121] After the first parking body 410 of the first parking member 400 moves in the deviation direction, the reset member 700 can move the first parking body 410 in a direction opposite to the deviation direction. Therefore, the reset member 700 can return the first parking body 410 to its initial position after the extension portion 420 and the latch 630 are forcibly separated, thereby preventing permanent loss of the main brake maintaining performance of the brake actuator 30.

[0122] As an example, the return member 700 can be a compression spring that is elastically deformable in its longitudinal direction. The return member 700 can be arranged such that its longitudinal direction is parallel to the longitudinal direction of the first output shaft 210. The central axis of the return member 700 can be positioned coaxially with the central axis of the first output shaft 210. The return member 700 can have two ends that respectively contact the upper surface of the first parking body 410 and the lower surface of the first transmission gear 310. Alternatively, the two ends of the return member 700 can respectively contact the lower surface of the first parking body 410 and the upper surface of the first motor 200.

[0123] When the first parking body 410 is in its initial position, the return member 700 can be installed in an untensioned or uncompressed neutral state. When the first parking body 410 moves in a deviated direction, the return member 700 can be longitudinally tensioned or compressed to accumulate elastic energy. After the extension portion 420 and the latch 630 are forcibly separated, the return member 700 can press or pull the first parking body 410 in a direction opposite to the deviated direction by the accumulated elastic energy, so that the first parking body 410 returns to its initial position. When the second parking body 610 rotates in the first rotation direction, the initial position of the first parking body 410 can be designed and changed in various ways within the range of the position where the latch 630 can be inserted between a pair of adjacent extension portions 420 associated therewith.

[0124] Although an example has been described above in which the first parking body 410 is installed to reciprocate in the longitudinal direction of the first output shaft 210, the present disclosure is not limited thereto. For example, the second parking body 610 can also be installed to reciprocate in the longitudinal direction of the second output shaft 510.

[0125] In this case, the return member 700 can be arranged such that its longitudinal direction is parallel to the longitudinal direction of the second output shaft 510, and can have two ends that respectively contact the second parking body 610 and the second motor 500 or the second parking body 610 and the housing 100.

[0126] The brake actuator 30 can also include a control module.

[0127] The control module is connected to the first motor 200 and the second motor 500, and controls the operations of the first motor 200 and the second motor 500. More specifically, the control module can control the operations of the first motor 200 and the second motor 500 based on a braking signal or a brake release signal generated by the driver's brake pedal operation or a parking brake command. The control module can be implemented as an integrated circuit (IC), a microcontroller (μC), a microprocessor, an application specific integrated circuit (ASIC), or a combination thereof, which can be electrically connected to the first motor 200 and the second motor 500 and can control whether the first output shaft 210 and the second output shaft 510 rotate, the rotational speeds of the first output shaft 210 and the second output shaft 510, etc. The control module can control the rotational directions of the first output shaft 210 and the second output shaft 510 in only one direction through on / off operations. Alternatively, the control module can control the rotational directions of the first output shaft 210 and the second output shaft 510 bidirectionally through multiple circuits. The control module can be disposed inside the housing 100, or can be coupled to the outer surface of the housing 100.

[0128] Hereinafter, the operation of the brake actuator 30 according to an embodiment of the present disclosure will be described.

[0129] Figures 9 to 11 is a view schematically showing a process of generating a parking braking force.

[0130] Reference Figures 1 to 11 , during parking braking, in a state where the second parking body 610 is in its initial position, the first motor 200 can rotate the first output shaft 210 in the direction of brake application ( Figure 9 the counterclockwise direction in

[0131] When the first output shaft 210 rotates in the direction of brake application, the rotational force of the first output shaft 210 can be transmitted to the piston unit 20 through the transmission gear 300, and the brake pad P can contact the brake disc D to generate a braking force in the vehicle.

[0132] In this case, the first parking member 400 can rotate in the direction of brake application together with the first output shaft 210.

[0133] Then, the second motor 500 can rotate the second output shaft 510 in the first rotational direction ( Figure 10 the counterclockwise direction in

[0134] When the second output shaft 510 rotates in the first rotation direction, the second parking body 610 rotates in the first rotation direction together with the second output shaft 510, and the latch 630 moves toward the first parking member 400.

[0135] When the second parking body 610 rotates in the first rotation direction by more than a set angle, the latch 630 can be inserted between any associated pair of adjacent extension portions 420.

[0136] When the second parking body 610 rotates in the first rotation direction, the first return member 640 can be elastically deformed to accumulate elastic energy to rotate the second parking body 610 in the second rotation direction.

[0137] Then, the operation of the first motor 200 is stopped, and a rotational force is generated in the brake release direction ( Figure 11 the clockwise direction in

[0138] the first output shaft 210 by the reaction force acting between the brake disc D and the brake pad P.

[0139] By the rotational force applied to the first output shaft 210 in the brake release direction, the extension portion 420 and the latch 630 are unlocked from each other, and a reaction force is generated in the first direction between the extension portion 420 and the latch 630. Figure 11 The second parking body 610 linearly moves in the first direction (

[0140] the right direction in

[0141] this) by the reaction force acting between the extension portion 420 and the latch 630.

[0142] When the second parking body 610 linearly moves in the first direction, the first return member 640 can be elastically deformed in a direction parallel to the first direction to accumulate elastic energy to linearly move the second parking body 610 in the second direction.

[0143] Then, the rotational force applied to the first output shaft 210 in the brake release direction can be offset by the locking force between the extension portion 420 and the latch 630 and the supporting force of the second stopper 662 relative to the first stopper 661, and the parking brake can be maintained by limiting the rotation of the first parking body 410 and the first output shaft 210.

[0144] Figures 12 to 14 is a view schematically showing a process of releasing the parking brake force.

[0145] refer to Figures 1 to 14 , when the parking brake is released, Figure 11 In the state, the first motor 200 can make the first output shaft 210 in the direction of brake application ( Figure 12 counterclockwise in the image) by a certain angle.

[0146] When the first output shaft 210 rotates in the brake application direction, the magnitude of the reaction force acting between the extension portion 420 and the latch 630 decreases.

[0147] Due to this reduction in the reaction force, the second parking body 610 can rotate in the second rotation direction ( Figure 13 The first return member 640 and the second return member 650 can be rotated in the clockwise direction in the second direction (in the clockwise direction in ... Figure 13 Linear movement (left direction in the figure).

[0148] When the second parking body 610 rotates in the rotation direction and linearly moves in the second direction, the latch 630 is separated from a pair of adjacent extension portions 420 , and rotation of the first parking body 410 and the first output shaft 210 is allowed.

[0149] Then, the first output shaft 210 can be moved in the brake release direction ( Figure 14 ) to release the parking brake.

[0150] Figure 15 and Figure 16 is a view schematically showing a process of forcibly releasing the parking brake force.

[0151] refer to Figures 1 to 16 , if the first output shaft 210 is not in the direction of brake application ( Figure 14 The second parking body 610 does not rotate in the second rotation direction (in the counterclockwise direction) due to the compression between the extension portion 420 and the latch 630 or the damage of the first return member 640. Figure 14 The first motor 200 forcibly rotates the first output shaft 210 in the direction of brake release (Figure 14 rotate in the clockwise direction (in the figure).

[0152] When the first output shaft 210 rotates in the direction of brake release, the magnitude of the reaction force acting between the extension part 420 and the latch 630 increases.

[0153] A part of the reaction force acting between the extension part 420 and the latch 630 is transmitted through the inclination angle of the side surface of the extension part 420 in a direction parallel to the longitudinal direction of the first output shaft 210.

[0154] When the reaction force acting between the extension part 420 and the latch 630 increases beyond the set magnitude, the first parking body 410 linearly moves in the deviation direction parallel to the longitudinal direction of the first output shaft 210 ( Figure 16 in the downward direction in the figure).

[0155] The extension part 420 can move relative to the latch 630 in the longitudinal direction of the first output shaft 210, and the extension part 420 and the latch 630 can be separated from each other.

[0156] During this process, the reset member 700 is elastically deformed in the longitudinal direction of the first output shaft 210 to accumulate elastic energy, thereby restoring the first parking body 410 to its initial position.

[0157] When the extension part 420 and the latch 630 are separated from each other, the first output shaft 210 can rotate in the direction of brake release.

[0158] Then, when the second parking body 610 returns to its initial position by the elastic restoring force of the first return member 640, the driving force of the second motor 500, or manually, the first parking body 410 can move in the direction opposite to the deviation direction ( Figure 16 in the upward direction in the figure), and can return to its original position.

[0159] Although the present disclosure has been described with respect to the embodiments shown in the drawings, it will be apparent to those skilled in the art that such embodiments are provided only by way of example. Those skilled in the art will understand that various modifications and other equivalent embodiments can be made without departing from the spirit and scope of the present disclosure defined in the claims.

Claims

1. A brake actuator, comprising: case; a first motor mounted in the housing; a transmission gear rotatably mounted in the housing and connected to the first motor; a first parking member configured to rotate together with the transmission gear; a second motor spaced apart from the first motor; as well as A second parking member is installed to be rotatable and linearly movable within the housing and is configured to selectively restrict rotation of the first parking member through operation of the second motor.

2. The brake actuator according to claim 1, wherein: The first parking structure comprises: A first parking body connected to a first output shaft of the first motor; and A plurality of extending portions extend from the first parking body and are arranged along a circumferential surface of the first parking body.

3. The brake actuator according to claim 2, wherein: Each of the extending portions extends obliquely with respect to a radial direction of the first parking body.

4. The brake actuator according to claim 2, wherein: The second parking structure comprises: A second parking body; a guide rail formed by the second parking body, the second output shaft of the second motor being inserted into the guide rail; and a latch extending from the second parking body and inserted between an associated pair of adjacent extending portions when the second parking body is rotated in a first rotation direction, The second parking body rotates at the same angular velocity as the second output shaft, and when the latch is inserted between an associated pair of adjacent extensions, the second parking body moves linearly in a first direction.

5. The brake actuator according to claim 4, wherein: The longitudinal direction of the guide rail extends in a direction parallel to the first direction.

6. The brake actuator according to claim 4, wherein: A width of the guide rail perpendicular to the first direction is smaller than one of a width of the second output shaft perpendicular to the longitudinal direction thereof.

7. The brake actuator according to claim 4, wherein: The second parking structure further comprises: a first return member connected to the second parking body and configured to press the second parking body in a second rotation direction opposite to the first rotation direction; and A second return member is connected to the second parking body and is configured to press the second parking body in a second direction opposite to the first direction.

8. The brake actuator according to claim 7, wherein: The first return member is configured to be elastically deformable, and both ends of the first return member are respectively connected to the second motor and the second parking body.

9. The brake actuator according to claim 8, wherein: The first return member is a torsion spring.

10. The brake actuator according to claim 7, wherein: The second return member is configured to be elastically deformable, and both ends of the first return member are respectively connected to the second output shaft and the second parking body.

11. The brake actuator according to claim 10, wherein: The second return member is a compression spring.

12. The brake actuator according to claim 4, wherein: The second parking body further includes a supporting member configured to limit a moving range of the second parking body relative to the first direction.

13. The brake actuator according to claim 12, wherein: The supporting member comprises: a first stopper extending from the second parking body; and A second stopper is disposed to face the first stopper and is configured to contact the first stopper when the second parking body moves in the first direction over a set distance.

14. The brake actuator according to claim 13, wherein: The second stop extends from the housing.

15. The brake actuator of claim 4, wherein: The first parking body is installed to be movable in the longitudinal direction of the first output shaft; and When a reaction force acting between an associated one of the plurality of extending portions and the latch increases beyond a set magnitude, the first parking body moves in a deviating direction parallel to a longitudinal direction of the first output shaft.

16. The brake actuator according to claim 15, wherein: The extending portion has a side surface inclined with respect to a longitudinal direction of the first output shaft. 17 . The brake actuator of claim 15 , further comprising a return member configured to move the first parking member in a direction opposite to the deviation direction.

18. The brake actuator according to claim 17, wherein: The return member is configured to be elastically deformable in a direction parallel to a longitudinal direction of the first output shaft, and both ends of the return member are in contact with the first parking body and the transmission gear, respectively.

19. The brake actuator according to claim 18, wherein: The return member is a compression spring.

20. A braking device, comprising: Caliper body; a piston unit movably mounted on the caliper body; as well as a brake actuator connected to the piston unit and configured to move the piston unit, Wherein, the brake actuator comprises: case; a first motor mounted in the housing; a transmission gear rotatably mounted in the housing and connected to the first motor; a first parking member configured to rotate together with the transmission gear; a second motor spaced apart from the first motor; and A second parking member is installed to be rotatable and linearly movable within the housing and is configured to selectively restrict rotation of the first parking member through operation of the second motor.

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