Vehicle brake device

Abstract

A vehicle brake apparatus can include a caliper body fixed to a vehicle body, a driving unit fixed to the caliper body and generating a rotational force, a piston unit movably installed in the caliper body and pressing or releasing a brake pad according to a moving direction of the piston unit, a transmission gear unit connected with the driving unit and rotated by the rotational force received from the driving unit, and a planetary gear unit fixed to the caliper body and moving the piston unit forward and backward as the transmission gear unit is rotated. According to the vehicle brake apparatus, the number and weight of parts can be reduced by eliminating a separate structure such as an actuator housing.

Description

Technical Field

[0001] Exemplary embodiments of this disclosure relate to a vehicle braking device, and more specifically, to a vehicle braking device that generates braking force by converting the driver's pedal operating force into an electrical signal. Background Technology

[0002] Generally speaking, a vehicle braking system is a device that uses driving force to push a piston, causing a plate-like component and a disc-like component to press against each other and using the friction between the plate-like component and the disc-like component to brake the vehicle.

[0003] An electromechanical brake (EMB) is a device that has an electric motor-driven actuator directly mounted on the caliper and generates braking force through a mechanism such as gears or screws without using a hydraulically pressed piston. EMB can perform active and independent braking for each wheel, enabling additional functions such as Anti-lock Braking System (ABS), Electronic Stability Controller (ESC), Traction Control System (TCS), Autonomous Emergency Braking (AEB), and main braking functions, thus achieving higher performance without hydraulic transmission delay.

[0004] Traditional EMB motors use ball screws to ensure rapid piston response and high efficiency. However, due to their structural characteristics, these ball screws cannot perform a self-locking function that would limit their own rotation. Therefore, when power to the motor is cut off, the repulsive force between the plate and the piston may randomly release the braking force.

[0005] To address these issues, after the main braking system provides braking force, the EMB also includes an Electronic Parking Brake (EPB) structure, which maintains the braking state via the parking brake. However, when the EPB structure is applied to the EMB, the capacity of the motor used for the main braking increases, and the gear reduction ratio also increases. Furthermore, even with the Electronic Control Unit (ECU) and actuators including the motor and gears mounted on the caliper, the increased weight places excessive load on the caliper, and the caliper is prone to vibration due to weight concentration.

[0006] The related technology disclosed herein was disclosed in Korean Patent Application No. 10-2010-0098846, entitled "Disc Brake with Parking Function," published on September 10, 2010. Summary of the Invention

[0007] This disclosure aims to provide a vehicle braking device that can reduce overall size and ensure stability against weight concentration and vibration.

[0008] Various embodiments relate to a vehicle braking device, including: a caliper body fixed to a vehicle body; a drive unit fixed to the caliper body and generating a rotational force; a piston unit movably mounted in the caliper body and compressing or releasing brake pads according to the direction of movement of the piston unit; a transmission gear unit connected to the drive unit and rotating by the rotational force received from the drive unit; and a planetary gear unit fixed to the caliper body and moving the piston unit forward and backward with the rotation of the transmission gear unit.

[0009] The caliper body may include: a bridge-like component; fingers extending from one side of the bridge-like component; a cylinder extending from the other side of the bridge-like component and configured to face the fingers; and a mounting assembly extending from the cylinder and supporting the drive unit and the planetary gear unit.

[0010] The assembly may include: an assembly body extending radially to one side of the cylinder body; a first assembly disposed on one side of the assembly body and supporting the drive unit; and a second assembly disposed on the other side of the assembly body and supporting the planetary gear unit.

[0011] The first assembly may include: a recessed groove in the assembly body, such that the drive unit is located in the recessed groove; an insertion hole through the recess, such that the output shaft of the drive unit is inserted into the insertion hole; and a fastening hole through the assembly body, such that a fastener for fastening the drive unit is inserted into the fastening hole.

[0012] The fastening hole can face the flange extending from the drive unit.

[0013] The first assembly may also include a seal disposed between the seat groove and the drive unit to prevent foreign matter from entering the drive unit.

[0014] The seal is elastically deformable and is positioned along the inner circumferential surface of the seat groove.

[0015] The second assembly can extend from the assembly body in a direction parallel to the axial direction of the piston unit.

[0016] The second assembly can be coaxially mounted with the piston unit.

[0017] The planetary gear unit may include: a ring gear fixed to a second assembly; a sun gear rotatably supported by the ring gear and meshing and engaging with the transmission gear unit; a plurality of planet gears meshing and engaging with the ring gear and the sun gear and rotating and revolve as the sun gear rotates; and a carrier connected to the planetary gears and transmitting the rotational force of the planetary gears to the piston unit.

[0018] The ring gear may include: a fixed member into which a second assembly is inserted; and a reducer coaxially arranged with the fixed member such that the inner circumferential surface of the reducer meshes and engages with the planetary gear.

[0019] The braking device may also include a support member disposed between the fixed member and the reducer, and extending inward along the radial direction of the ring gear.

[0020] The fastener can be secured when its inner circumferential surface is pressed into the outer circumferential surface of the second assembly.

[0021] The fastener can be screwed onto the second assembly.

[0022] The second assembly may have multiple first connecting holes disposed therein, and the fastener has multiple second connecting holes coaxially aligned with the first connecting holes, wherein the second assembly and the fastener are connected to each other by fixing bolts, the fixing bolts passing sequentially through the second connecting holes and the first connecting holes.

[0023] The transmission gear unit may include: a first transmission gear that rotates together with the output shaft of the drive unit; and a second transmission gear that rotates together with the first transmission gear and meshes with and is connected to the sun gear.

[0024] The diameter of the second transmission gear can be larger than that of the first transmission gear.

[0025] The braking device may also include a housing detachably connected to the assembly, the housing covering the transmission gear unit and the planetary gear unit.

[0026] According to the vehicle braking device disclosed herein, the drive unit, transmission gear unit, and planetary gear unit can be directly fixed to the caliper body via mounting hardware, which allows for a reduction in the number of parts and weight by eliminating separate structures (such as actuator housings) found in the prior art. Furthermore, the center of gravity can be positioned close to the central region of the caliper body, which reduces weight concentration and vibration.

[0027] Furthermore, according to the vehicle braking device disclosed herein, since the ring gear is fixed on the second assembly and the overall reduction ratio of the planetary gear unit is increased, the length or size of the transmission gear unit required to increase the magnitude of the rotational force generated by the drive unit can be reduced, and the overall length of the actuator can be reduced. Attached Figure Description

[0028] Figure 1 This is a perspective view schematically illustrating the configuration of a vehicle braking device according to an embodiment of the present disclosure;

[0029] Figure 2 This is a schematic front view illustrating the configuration of a vehicle braking device according to an embodiment of the present disclosure;

[0030] Figure 3 This is a schematic cross-sectional view illustrating the configuration of a vehicle braking device according to an embodiment of the present disclosure;

[0031] Figure 4 This is a perspective view schematically illustrating the structure of an assembly according to an embodiment of the present disclosure;

[0032] Figure 5 This is a perspective view showing the structure of the assembly according to an embodiment of the present disclosure when viewed from different angles;

[0033] Figure 6 and Figure 7 This is a diagram schematically illustrating a modified example of the connection structure between the first assembly and the drive unit according to an embodiment of the present disclosure;

[0034] Figure 8 This is an exploded perspective view schematically illustrating the configuration of a planetary gear unit according to an embodiment of the present disclosure;

[0035] Figure 9 This is an unfolded cross-sectional view schematically illustrating the configuration of a planetary gear unit according to an embodiment of the present disclosure;

[0036] Figure 10 An exploded perspective view schematically illustrating a modified example of a planetary gear unit according to an embodiment of the present disclosure; and

[0037] Figure 11 This is an unfolded sectional view schematically illustrating a modified example of a planetary gear unit according to an embodiment of the present disclosure. Detailed Implementation

[0038] Throughout this specification, when an element is referred to as "connected to" or "coupled to" another element, it can indicate that an element is "directly connected or coupled to" another element, or that an element is "indirectly connected or coupled to" another element through which it is situated. In this specification, when an element "includes or has" a component, it can indicate that the element does not exclude another component, but may further include or have another component, unless otherwise stated.

[0039] In this specification, the same reference numerals can denote the same parts. Although the same or similar reference numerals are not mentioned or described in a particular drawing, the reference numerals can be described with reference to other drawings. Furthermore, although a part is not represented by a reference numeral in a particular drawing, the part can be described with reference to other drawings. In addition, the number, shape, and size of the sub-parts included in the drawings of this specification, as well as the relative differences between the dimensions, are provided for ease of description and are not intended to limit the embodiments, and can be set to various values.

[0040] Figure 1 This is a perspective view schematically illustrating the configuration of a vehicle braking device according to an embodiment of the present disclosure. Figure 2 This is a schematic front view illustrating the configuration of a vehicle braking device according to an embodiment of the present disclosure, and Figure 3 This is a schematic cross-sectional view illustrating the configuration of a vehicle braking device according to an embodiment of the present disclosure.

[0041] refer to Figures 1 to 3 According to an embodiment of the present disclosure, the vehicle braking device 1 includes a caliper body 100, a drive unit 200, a piston unit 300, a transmission gear unit 400, a planetary gear unit 500, a parking gear unit 600, a restraint unit 700, and a housing 800.

[0042] The caliper body 100 is fixed to the vehicle body by a torque member 10 and serves to support the drive unit 200, piston unit 300, transmission gear unit 400, planetary gear unit 500, and constraint unit 700, as described below. Both sides of the caliper body 100 are slidably connected to the torque member 10 via guide pins 20. In this configuration, the caliper body 100 can slide in a direction parallel to the axial direction of the brake disc (not shown). The caliper body 100 slides in a direction parallel to the axial direction of the brake disc (not shown) due to the reaction force generated when the piston unit 300 presses down on the brake pad 30, as described below.

[0043] According to an embodiment of the present disclosure, the caliper body 100 includes a bridge-shaped member 110, a finger-shaped member 120, a cylinder body 130, and an assembly 140.

[0044] The bridge-shaped member 110 forms the upper outer portion of the caliper body 100. According to embodiments of this disclosure, the bridge-shaped member 110 can be formed in the shape of a plate, with its inner surface spaced a predetermined distance from the outer circumferential surface of the brake disc, while facing the outer circumferential surface of the brake disc. The specific shape and area of ​​the bridge-shaped member 110 can be varied in design depending on the dimensions of the brake disc, etc.

[0045] A finger 120 extends from one side of the bridge-shaped member 110 and forms the front outer side of the caliper body 100. According to an embodiment of the present disclosure, the finger 120 extends vertically downward from the front end of the bridge-shaped member 110. The finger 120 has an inner surface facing a brake pad 30 disposed outside a brake disc in the lateral direction of the vehicle, the brake disc being located between a pair of brake pads 30. The finger 120 squeezes or releases the brake pad 30 while sliding on the caliper body 100.

[0046] The cylinder body 130 extends from the other side of the bridge-shaped member 110, forming the outer rear portion of the caliper body 100. The cylinder body 130 movably supports the piston unit 300, as described below. According to an embodiment of the present disclosure, the cylinder body 130 extends vertically downward from the rear end of the bridge-shaped member 110. The cylinder body 130 is formed as a hollow cylinder with one side open. The open side of the cylinder body 130 faces the brake pad 30, which is disposed inside the brake disc along the width direction of the vehicle, the brake disc being located between a pair of brake pads 30.

[0047] Mounting accessory 140 extends from cylinder block 130 and supports drive unit 200, transmission gear unit 400, and planetary gear unit 500, which will be described below. That is, mounting accessory 140 serves as a component providing mechanical connection between drive unit 200, transmission gear unit 400, and planetary gear unit 500 and caliper body 100. Through mounting accessory 140, drive unit 200, transmission gear unit 400, and planetary gear unit 500 can be directly fixed to caliper body 100 without separate structures, such as actuator housings, which reduces the number of parts. Furthermore, the center of gravity can be set close to the central region of caliper body 100, which reduces weight concentration and vibration.

[0048] Figure 4 This is a perspective view schematically illustrating the configuration of an assembly according to an embodiment of the present disclosure, and Figure 5 This is a perspective view schematically illustrating the configuration of the assembly according to an embodiment of the present disclosure when viewed from different angles.

[0049] refer to Figure 4 and Figure 5 According to an embodiment of the present disclosure, the assembly 140 includes an assembly body 150, a first assembly 160, and a second assembly 170.

[0050] The assembly body 150 forms the schematic exterior of the assembly 140. According to an embodiment of this disclosure, the assembly body 150 can be formed in the shape of a plate extending from the opposite surface of the cylinder body 130 (i.e., the surface of the cylinder body 130 that is configured to face the brake pad 30) to one radial side of the cylinder body 130. Figure 4 (Left side of the image). When manufacturing the caliper body 100, the assembly body 150 can be integrated with the cylinder body 130 by casting. Depending on the configuration of the drive unit 200, transmission gear unit 400, and planetary gear unit 500, in addition to... Figure 4 and Figure 5 In addition to the shape shown, the specific cross-sectional shape of the assembly body 150 can be changed in different ways in the design.

[0051] The first assembly 160 is located on one side of the assembly body 150 and supports the drive unit 200.

[0052] The first fitting 160 according to an embodiment of the present disclosure includes a seat groove 161, an insertion hole 162, a fastening hole 163, and a seal 164.

[0053] The seat groove 161 is formed in the shape of a recess, which is recessed from the inner surface of the mounting body 150 facing the cylinder block 130 into the interior of the mounting body 150. Figure 4 In the assembly, a mounting groove 161 is located on the left side of the mounting body 150. The mounting groove 161 has a generally circular cross-section, and its central axis is parallel to the central axis of the cylinder block 130. The drive unit 200, described below, is inserted into the mounting groove 161, with its front surface portion resting on the bottom surface of the mounting groove 161. The diameter and depth of the mounting groove 161 can be varied according to the dimensions of the drive unit 200, as described below.

[0054] The insertion hole 162 is formed into the shape of a hole through the seat groove 161. The central axis of the insertion hole 162 is coaxial with the central axis of the seat groove 161. The insertion hole 162 may have a substantially circular cross-section. The output shaft 201 (described below) extending from the front surface portion of the drive unit 200 is inserted into the insertion hole 162. The diameter of the insertion hole 162 may be varied in design depending on the diameter of the output shaft 201.

[0055] The fastening hole 163 is spaced apart from the insertion hole 162 and forms a hole through the assembly body 150. For example... Figure 4 and Figure 5 As shown, the fastening hole 163 can be located at a position where the fastening hole 163 directly passes through the seat groove 161. The fastening hole 163 can be formed as a plurality of fastening holes. The plurality of fastening holes 163 are each located at a predetermined distance from the insertion hole 162 in the radial direction and are located in the circumferential direction of the insertion hole 162 so as to be spaced apart from each other.

[0056] Fastener 165 is inserted into fastening hole 163 and fastened to drive unit 200 to fix drive unit 200 located in seat groove 161. Fastener 165 according to embodiments of the present disclosure may be formed in the shape of a bolt, with threads formed on its outer circumferential surface. Fastener 165 is provided as a plurality of fasteners inserted into various fastening holes 163. The diameter of fastening hole 163 may be varied in design depending on the diameter of fastener 165.

[0057] A seal 164 is disposed between the seat groove 161 and the drive unit 200 to prevent foreign matter from entering the drive unit 200. According to embodiments of the present disclosure, the seal 164 is substantially annular and is disposed along the inner circumferential surface of the seat groove 161. The seal 164 may be made of an elastically deformable material, such as rubber or silicone. The seal 164 is in close contact with the circumferential surface of the front surface portion of the drive unit 200 inserted into the seat groove 161. Therefore, the seal 164 can seal the gap between the drive unit 200 and the seat groove 161 to prevent foreign matter such as water or dust from entering the drive unit 200, and can elastically deform to counteract vibrations generated by the drive unit 200.

[0058] The second assembly 170 is disposed on the other side of the assembly body 150 for supporting the planetary gear unit 500. According to an embodiment of this disclosure, the second assembly 170 can be formed into a cylindrical shape, protruding from the outer surface of the assembly body 150 in a direction parallel to the axial direction of the piston unit 300, as described below. The central axis of the second assembly 170 is coaxial with the central axis of the piston unit 300. A specific connection structure between the second assembly 170 and the planetary gear unit 500 will be described below.

[0059] The drive unit 200 is fixed to the caliper body 100 and generates rotational force using power received from an external source. The drive unit 200 according to an embodiment of this disclosure can be exemplified as a cylindrical motor electrically connected to the vehicle's battery, receiving power from the battery, and generating rotational force through electromagnetic interaction between the stator and rotor. An output shaft 201 that outputs the rotational force generated when the drive unit 200 rotates on its central axis extends from the front surface portion of the drive unit 200.

[0060] In the following text, reference will be made to Figure 1 and Figure 5 The connection structure between the drive unit 200 and the first assembly 160 is described in detail.

[0061] With the output shaft 201 positioned facing the seat groove 161, the front surface portion of the drive unit 200 is inserted into the seat groove 161.

[0062] The output shaft 201, which protrudes from the front surface portion of the drive unit 200, is inserted through the insertion hole 162 and has an end that extends out of the assembly body 150.

[0063] The drive unit 200 inserted into the seat groove 161 is supported while its front surface portion edge is in close contact with the seal 164.

[0064] Fastener 165 is inserted sequentially through fastening hole 163 and front surface portion of drive unit 200, and screwed to front surface portion of drive unit 200 by threads formed on its outer circumferential surface.

[0065] Figure 6 and Figure 7 This is a diagram schematically illustrating a modified example of the connection structure between the first assembly and the drive unit according to an embodiment of the present disclosure.

[0066] In the following text, reference will be made to Figure 6 and Figure 7 A detailed description of a modified example of the connection structure between the drive unit 200 and the first assembly 160 is provided. During this process, for ease of description, Figure 4 and Figure 5 The overlapping description of the connection structure between the drive unit 200 and the first assembly 160 shown in the figure will be omitted here.

[0067] refer to Figure 6 According to this disclosure, the drive unit 200 includes a plurality of flanges 210 formed thereon.

[0068] According to embodiments of the present disclosure, the flange 210 can be formed in the shape of a plate, extending radially from the outer circumferential surface of the drive unit 200. A plurality of flanges 210 are arranged along the circumferential direction of the drive unit 200 so as to be spaced apart from each other at a predetermined distance. The number of the plurality of flanges 210 is not limited to... Figure 6 and Figure 7 The quantity shown can be changed to various values.

[0069] like Figure 7 As shown, fastening holes 163 are formed in the edge region of the seat groove 161 to directly penetrate the assembly body 150 while facing the corresponding flange 210. Multiple fastening holes 163 are provided at positions facing the corresponding flange 210.

[0070] When the front surface portion of the drive unit 200 is inserted into the seat groove 161, the flange 210 contacts the inner surface of the assembly body 150 formed along the edge region of the seat groove 161 and is supported by the inner surface of the assembly body 150.

[0071] Fastener 165 is inserted sequentially through flange 210 and fastening hole 163, and screwed to flange 210 by threads formed on its outer peripheral surface.

[0072] The piston unit 300 is movably mounted in the caliper body 100, or more specifically in the cylinder 130. Within the cylinder 130, the piston unit 300 moves forward and backward under the rotational force generated by the drive unit 200. The piston unit 300 applies or removes braking force from the vehicle, while simultaneously pressing or releasing the brake pads 30 from the brake disc according to the direction of its forward or backward movement.

[0073] According to an embodiment of the present disclosure, the piston unit 300 includes a ball screw 310, a ball nut 320, a rolling element 330, and a piston 340.

[0074] The ball screw 310 receives rotational force generated by the drive unit 200 via the planetary gear unit 500, which will be described below, and rotates by the received rotational force. According to an embodiment of this disclosure, the ball screw 310 is substantially rod-shaped and rotatably mounted in a cylinder 130. The longitudinal direction of the ball screw 310 is parallel to the longitudinal direction of the cylinder 130. The ball screw 310 has a groove formed on its outer circumferential surface such that half a circumference of the rolling element 330, which will be described below, lies within the groove. The groove extends helically in the longitudinal direction of the ball screw 310 and provides a circulation path for the rolling element 330. The rear end portion of the ball screw 310 protrudes to the outside of the second mounting 170 via the central axis of the second mounting 170. The rear end portion of the ball screw 310 is connected to the carrier 540 of the planetary gear unit 500, which will be described below. More specifically, spline teeth can be formed on the outer circumferential surface of the rear end portion of the ball screw 310 and mesh with and connect to the inner circumferential surface of the carrier 540. Therefore, when the carrier 540 rotates, the ball screw 310 can rotate together with the carrier 540 on the central axis.

[0075] As the ball screw 310 rotates, the ball nut 320 reciprocates linearly in the longitudinal direction of the ball screw 310. According to embodiments of the present disclosure, the ball nut 320 may be formed in a hollow cylindrical shape to surround the outer circumferential surface of the ball screw 310. The inner circumferential surface of the ball nut 320 is spaced a predetermined distance from the outer circumferential surface of the ball screw 310 and faces the outer circumferential surface of the ball screw 310. The ball nut 320 has a groove formed on its inner circumferential surface such that the other half of the circumference of the rolling element 330, described below, is located in the groove. The groove extends helically in the longitudinal direction of the ball nut 320 and provides a cyclic path for the rolling element 330. As the ball screw 310 rotates, the ball nut 320 reciprocates linearly in the longitudinal direction of the ball screw 310 through the cyclic motion of the rolling element 330.

[0076] A rolling element 330 is disposed between the ball screw 310 and the ball nut 320, with its two sides making rolling contact with the ball screw 310 and the ball nut 320, respectively. According to this embodiment, the rolling element 330 is substantially spherical and is mounted between the ball screw 310 and the ball nut 320. The circumference of the rolling element 330 makes rolling contact with grooves formed on the outer circumferential surface of the ball screw 310 and the inner circumferential surface of the ball nut 320. When the ball screw 310 rotates, the rolling element 330 moves cyclically along the grooves, converting the rotation of the ball screw 310 into linear reciprocating motion of the ball nut 320.

[0077] The piston 340 reciprocates linearly with the ball nut 320, compressing or releasing the brake pad 30 according to the direction of movement. According to an embodiment of this disclosure, the piston 340 is mounted in a cylinder 130 to slide in the longitudinal direction of the cylinder 130. The rear end of the piston 340 is integrally connected to the front end of the ball nut 320 and can reciprocate linearly with the ball nut 320 in the longitudinal direction of the cylinder 130. As the ball nut 320 moves forward, the front end of the piston 340 contacts the brake pad 30 and presses the brake pad 30 against the brake disc, thereby generating braking force. When the ball nut 320 moves backward, the piston 340 separates from the brake pad 30 and releases the brake pad 30, thereby eliminating the braking force.

[0078] The transmission gear unit 400 rotates by the rotational force received from the drive unit 200 and transmits the rotational force generated by the drive unit 200 to the planetary gear unit 500, which will be described below.

[0079] According to an embodiment of the present disclosure, the transmission gear unit 400 includes a first transmission gear 410 and a second transmission gear 420.

[0080] The first transmission gear 410 is connected to the output shaft 201 of the drive unit 200 and rotates together with the output shaft 201 of the drive unit 200. According to embodiments of the present disclosure, the first transmission gear 410 can be formed as a hollow helical gear or a spur gear, with teeth on its outer circumferential surface. The central axis of the first transmission gear 410 is coaxially arranged with the output shaft 201 of the drive unit 200. The output shaft 201 is inserted through the center of the first transmission gear 410. During operation of the drive unit 200, the first transmission gear 410 rotates at the same angular velocity as the output shaft 201 of the drive unit 200.

[0081] The second transmission gear 420 meshes with and is connected to the first transmission gear 410, and rotates as the first transmission gear 410 rotates. According to embodiments of this disclosure, the second transmission gear 420 can be formed as a hollow helical gear or a spur gear, with teeth on its outer circumferential surface. The second transmission gear 420 meshes with and is connected between the first transmission gear 410 and the sun gear 520 of the planetary gear unit 500, as will be described below. The central axis of the second transmission gear 420 is arranged parallel to the central axis of the first transmission gear 410. The second transmission gear 420 is rotatably supported by the mounting body 150 via a separate rotation shaft (not shown). The second transmission gear 420 is formed to have a larger diameter than the first transmission gear 410. Therefore, the second transmission gear 420 can increase the magnitude of the rotational force transmitted from the first transmission gear 410 to the planetary gear unit 500.

[0082] The planetary gear unit 500 is fixed to the caliper body 100 and moves the piston unit 300 forward and backward as the transmission gear unit 400 rotates.

[0083] Figure 8 This is an exploded perspective view schematically illustrating the configuration of a planetary gear unit according to an embodiment of the present disclosure. Figure 9 This is a schematic unfolded cross-sectional view illustrating a planetary gear unit configuration according to an embodiment of the present disclosure.

[0084] refer to Figure 8 and 9 The planetary gear unit 500 according to an embodiment of the present disclosure includes a ring gear 510, a sun gear 520, planetary gears 530, and a carrier 540.

[0085] The ring gear 510 is fixed to the second assembly 170 and supports the sun gear 520, planetary gear 530, and carrier 540, which will be described below. Therefore, the ring gear 510 can directly support the sun gear 520, planetary gear 530, and carrier 540 relative to the caliper body 100 without the need for separate structures such as actuator housings, which allows for weight and cost reduction. Furthermore, since the ring gear 510 is fixed to the second assembly 170 and increases the overall reduction ratio of the planetary gear unit 500, the length or size of the transmission gear unit 400 required to increase the magnitude of the rotational force generated by the drive unit 200 can be reduced, and the overall length of the assembly 140 can be reduced.

[0086] The ring gear 510 according to an embodiment of the present disclosure includes a fixing member 511, a reducer 512, and a support member 513.

[0087] The fastener 511 forms the outer side of one side of the ring gear 510 and is fixed to the second assembly 170. According to an embodiment of this disclosure, the fastener 511 can be formed as a hollow cylinder with openings on both sides. When the second assembly 170 is inserted into the fastener 511, the inner circumferential surface of the fastener 511 is press-fitted onto the outer circumferential surface of the second assembly 170, thereby fixing the fastener 511.

[0088] The reducer 512 forms the outer side of the other side of the ring gear 510 and meshes and engages with the planetary gear 530, as will be described below. According to an embodiment of this disclosure, the reducer 512 can be formed into a cylindrical shape with openings on both sides. The reducer 512 has gear teeth formed on its inner circumferential surface for meshing and engaging with the outer circumferential surface of the planetary gear 530. The central axis of the reducer 512 is coaxial with the central axis of the retainer 511. In this case, the ends of the retainer 511 and the reducer 512 face each other and can be connected into a single body to form a cylindrical shape that extends continuously in the axial direction of the ball screw 310.

[0089] A support member 513 is disposed between the fixing member 511 and the reducer 512 and supports the carrier 540, which will be described below. According to an embodiment of this disclosure, the support member 513 may have a disc shape extending inwardly in the radial direction of the ring gear 510 from the boundary line between the fixing member 511 and the reducer 512. The support member 513 has a through hole 514 formed at its center, such that the rear end of the ball screw 310, which protrudes outside the second assembly 170, passes through the through hole 514.

[0090] The sun gear 520 is rotatably supported by the ring gear 510 and meshes with and is connected to the transmission gear unit 400.

[0091] According to an embodiment of the present disclosure, the sun gear 520 includes a first sun gear 521 and a second sun gear 522.

[0092] The first sun gear 521 meshes with and is connected to the second transmission gear 420, and rotates as the second transmission gear 420 rotates. According to an embodiment of this disclosure, the first sun gear 521 is formed as a cylinder with an opening on one side. The first sun gear 521 is configured such that its open side faces the ring gear 510. The ring gear 510, or more specifically, the reducer 512, is inserted into the first sun gear 521, and the inner circumferential surface of the first sun gear 521 rotatably contacts the outer circumferential surface of the reducer 512. The first sun gear 521 has gear teeth extending from its outer circumferential surface and meshes with and is connected to the outer circumferential surface of the second transmission gear 420.

[0093] The second sun gear 522 extends from the first sun gear 521 and meshes with and engages with the planetary gear 530, as will be described below. According to an embodiment of this disclosure, the second sun gear 522 can be formed as a cylinder extending from the center of the first sun gear 521 to the open side of the first sun gear 521. The diameter of the second sun gear 522 is smaller than that of the first sun gear 521. The central axis of the second sun gear 522 is coaxial with the central axis of the first sun gear 521. The second sun gear 522 has gear teeth extending from its outer circumferential surface and meshes with and engages with the outer circumferential surface of the planetary gear 530.

[0094] Planetary gear 530 meshes and engages with ring gear 510 and sun gear 520, and rotates and revolves around the sun gear 520 as the sun gear 520 rotates. According to an embodiment of this disclosure, planetary gear 530 can be formed in a cylindrical shape with gear teeth formed on its outer circumferential surface. Planetary gear 530 is rotatably mounted in reducer 512. The central axis of planetary gear 530 is spaced a predetermined distance from the central axis of reducer 512 in the radial direction and is arranged parallel to the central axis of reducer 512. One side of the circumference of planetary gear 530 meshes and engages with the inner circumferential surface of reducer 512, and the other side of the circumference of planetary gear 530 meshes and engages with the outer circumferential surface of second sun gear 522. Planetary gear 530 receives rotational force from second sun gear 522 and rotates around the central axis of reducer 512 while rotating on its central axis. Planetary gear 530 can be formed as a plurality of planetary gears. The plurality of planetary gears 530 are arranged in the circumferential direction of reducer 512 so as to be spaced apart from each other by a predetermined distance. Figure 8 Four planetary gears 530 are shown. However, the number of planetary gears is not limited to this and can be changed to various values.

[0095] The carrier 540 is connected to the planetary gear 530 and transmits the rotational force of the planetary gear 530 to the piston unit 300. The carrier 540 according to an embodiment of the present disclosure is formed in a substantially disk shape and is disposed between the support member 513 and the planetary gear 530.

[0096] The carrier 540 has a connecting shaft 541 connected to the planetary gear 530. According to an embodiment of this disclosure, the connecting shaft 541 can be formed into the shape of a rod extending from one surface of the carrier 540, facing the planetary gear 530. The central axis of the connecting shaft 541 is arranged parallel to the central axis of the carrier 540. The connecting shaft 541 is inserted through the central axis of the planetary gear 530 and rotatably supports the planetary gear 530. The connecting shaft 541 is provided as a plurality of connecting shafts rotatably supporting the respective planetary gears 530. The connecting shaft 541 transmits the rotational force generated by the rotation of the planetary gear 530 to the carrier 540. Therefore, when the planetary gear 530 rotates, the carrier 540 can rotate on its central axis.

[0097] The carrier 540 has a connecting portion 542 connected to the ball screw 310. According to an embodiment of the present disclosure, the connecting portion 542 can be formed into a hole shape passing through the central axis of the carrier 540. The connecting portion 542 has a cross-section corresponding to the rear end of the ball screw 310, and splines are formed on the rear end of the ball screw 310. When the rear end of the ball screw 310 is inserted into the connecting portion 542, the connecting portion 542 engages and connects with the outer circumferential surface of the rear end of the ball screw 310. Therefore, the carrier 540 can rotate on its central axis and transmit rotational force to the ball screw 310.

[0098] Figure 10 This is an exploded perspective view schematically illustrating a modified example of a planetary gear unit according to an embodiment of the present disclosure. Figure 11 This is an unfolded sectional view schematically illustrating a modified example of a planetary gear unit according to an embodiment of the present disclosure.

[0099] In the following text, reference will be made to Figure 10 and Figure 11 A detailed description is provided of a modified example of the planetary gear unit 500 according to an embodiment of this disclosure. In this process, for ease of description, Figure 8 and 9 The overlapping description of the planetary gear unit 500 shown will be omitted here.

[0100] In this modified example, the ring gear 510 can be screwed to the second assembly 170 via a fixing bolt 516.

[0101] More specifically, the second assembly 170 has a plurality of first connecting holes 171 formed through the outer circumferential surface of the second assembly 170 in the radial direction. The plurality of first connecting holes 171 are arranged in the circumferential direction of the second assembly 170 so as to be spaced apart from each other by a predetermined distance. The first connecting holes 171 have threads formed on their inner circumferential surfaces.

[0102] The fastener 511 has a plurality of second connecting holes 515 formed in the radial direction of the fastener 511 through the outer circumferential surface of the fastener 511. The plurality of second connecting holes 515 are arranged in the circumferential direction of the fastener 511 so as to be spaced apart from each other by a predetermined distance. The second connecting holes 515 are coaxially aligned with the corresponding first connecting holes 171. The diameter of the second connecting holes 515 may be larger than the diameter of the first connecting holes 171.

[0103] The fixing bolt 516 can be formed into a bolt shape where one end has a larger diameter than the other end. The other end of the fixing bolt 516 has threads formed on its outer circumferential surface. The other end of the fixing bolt 516 is tightened sequentially through the second connecting hole 515 and the first connecting hole 171 to the inner circumferential surface of the first connecting hole 171. Since the other end of the fixing bolt 516 is fully engaged with the first connecting hole 171, one end of the fixing bolt 516 is located in the second connecting hole 515. Therefore, the fixing bolt 516 can reliably fix the ring gear 510 to the second assembly 170 without being disturbed by the rotation of the sun gear 520.

[0104] The parking gear unit 600 receives rotational force from the drive unit 200 and rotates together with the transmission gear unit 400. According to an embodiment of this disclosure, the parking gear unit 600 is coaxially arranged with the first transmission gear 410 and mounted at the end of the output shaft 201 of the drive unit 200. When the output shaft 201 rotates, the parking gear unit 600 can rotate on its centerline axis at the same angular velocity as the first transmission gear 410. Therefore, compared to when the parking gear unit 600 is connected to the second transmission gear 420 or has a planetary gear unit 500 with rotational force increased by gear ratio, the parking gear unit 600 can reduce the magnitude of the load applied to the constraint unit 700, which will be described below. The parking gear unit 600 has a plurality of parking protrusions formed on its outer circumferential surface to protrude in the radial direction of the parking gear unit 600. The plurality of parking protrusions are arranged along the circumferential direction of the parking gear unit 600 to be spaced apart from each other by a predetermined distance.

[0105] The constraint unit 700 is positioned facing the parking gear unit 600 and selectively fixed to it to restrict or allow rotation of the parking gear unit 600. More specifically, during parking braking, the constraint unit 700 is fixed to the parking gear unit 600, while the piston unit 300 pressurizes the brake pads 30 and restricts rotation of the parking gear unit 600, the drive gear unit 400, and the planetary gear unit 500. Furthermore, when the parking brake is released, the constraint unit 700 disengages from the parking gear unit 600, allowing rotation of the parking gear unit 600, the drive gear unit 400, and the planetary gear unit 500. Therefore, although the rotational force generated by the drive unit 200 ceases during parking braking, the constraint unit 700 prevents potential loss of braking force when the drive gear unit 400 and the planetary gear unit 500 rotate randomly due to the reaction force of the piston unit 300 and the brake pads 30.

[0106] According to an embodiment of the present disclosure, the constraint unit 700 includes a parking drive unit 710, a constraint rod 720, and a constraint member 730.

[0107] The parking drive unit 710 is coupled to and supported by the caliper body 100, or more specifically, the mounting assembly 140, and generates rotational force through power received from an external source. The parking drive unit 710 according to embodiments of this disclosure can be exemplified as a motor electrically connected to the vehicle's battery, receiving power from the battery, and generating rotational force through electromagnetic interaction between the stator and rotor.

[0108] The constraint rod 720 moves forward and backward according to the rotational force generated by the parking drive unit 710. According to an embodiment of this disclosure, the constraint rod 720 is formed in a substantially cylindrical shape and is disposed between the parking gear unit 600 and the parking drive unit 710. The side of the constraint rod 720 facing the parking gear unit 600 can be screwed onto the output shaft of the parking gear unit 710, converting the rotation of the parking drive unit 710 into linear reciprocating motion. The longitudinal direction of the constraint rod 720 is perpendicular to the central axis of the parking gear unit 600.

[0109] A constraint member 730 extends from the constraint rod 720 and is fixed to or separated from the parking gear unit 600 depending on the direction of movement of the constraint rod 720. According to an embodiment of the present disclosure, the constraint member 730 protrudes from the opposite edge of the constraint rod 720 facing the parking gear unit 600 toward the outer circumferential surface of the parking gear unit 600. The constraint members 730 may be provided as a pair of constraint members. The pair of constraint members 730 are spaced apart from each other relative to the central axis of the constraint rod 720, while facing each other. When the constraint rod 720 moves forward toward the parking gear unit 600 during parking braking, the pair of constraint members 730 locks onto a parking protrusion formed on the outer circumferential surface of the parking gear unit 600 and restricts rotation of the parking gear unit 600. Furthermore, when the parking brake is released, as the constraint rod 720 moves backward in a direction away from the parking gear unit 600, the pair of constraint members 730 separates from the parking protrusion and allows rotation of the parking gear unit 600. Figure 1 and Figure 2 Apart from the shape shown, the specific shape of the constraint member 730 can be varied in design as long as the constraint member 730 can be locked and connected to the parking gear unit 600.

[0110] The housing 800 is detachably connected to the assembly 140 and covers the transmission gear unit 400, planetary gear unit 500, and constraint unit 700. Therefore, the housing 800 can prevent foreign substances such as water and dust from entering the transmission gear unit 400, planetary gear unit 500, and constraint unit 700. According to an embodiment of this disclosure, the housing 800 can be formed into a hollow cover shape with one side open. The housing 800 has a cross-section corresponding to the cross-section of the assembly body 150. The open side of the housing 800 faces the assembly body 150 and is detachably connected to the assembly body 150 by screws or the like. In this case, an O-ring can be additionally installed on the contact area between the assembly body 150 and the housing 800, thus sealing the internal space of the housing 800 more effectively.

[0111] Although exemplary embodiments of this disclosure are disclosed for illustrative purposes, those skilled in the art will understand that various modifications, additions, and substitutions may be made without departing from the scope and spirit of this disclosure as defined in the accompanying technical solutions.

Claims

1. A vehicle braking device, comprising: The caliper body is fixed to the vehicle body; A drive unit, which is fixed to the caliper body, generates rotational force; A piston unit is movably mounted in the caliper body and compresses or releases the brake pads according to the direction of movement of the piston unit; A transmission gear unit, connected to the drive unit, and rotating by a rotational force received from the drive unit; and A planetary gear unit, which is fixed to the caliper body, moves the piston unit forward and backward as the transmission gear unit rotates; The planetary gear unit includes: A ring gear, which is fixed to a part of the caliper body; The sun gear is rotatably supported by the ring gear and meshes with and connects to the transmission gear unit; Multiple planetary gears, which mesh and connect with the ring gear and the sun gear, and rotate and revolve as the sun gear rotates; and The carrier is connected to the planetary gear and transmits the rotational force of the planetary gear to the piston unit; The ring gear includes: A fastener, which is fixed to a portion of the caliper body; A speed reducer, coaxially arranged with the fixed member, such that the inner circumferential surface of the speed reducer meshes and engages with the planetary gear; and A support member is disposed between the fixing member and the reducer and extends inward along the radial direction of the ring gear.

2. The vehicle braking device according to claim 1, wherein, The caliper body includes: Bridge-shaped component; Finger-like structures extending from one side of the bridge-like structure; A cylinder body extending from the other side of the bridge-like member and configured to face the fingers; and An assembly that extends from the cylinder block and supports the drive unit and the planetary gear unit.

3. The vehicle braking device according to claim 2, wherein, The assembly includes: An assembly body extends radially to one side of the cylinder body; A first assembly component, disposed on one side of the assembly body, supports the drive unit; and The second assembly is located on the other side of the assembly body and supports the planetary gear unit.

4. The vehicle braking device according to claim 3, wherein, The first assembly includes: A recessed seat is provided in the assembly body, such that the drive unit is located in the recessed seat. An insertion hole, configured to pass through the seat groove, such that the output shaft of the drive unit is inserted into the insertion hole; and A fastening hole is provided, which is configured to pass through the assembly body, such that a fastener fixed to the drive unit is inserted into the fastening hole.

5. The vehicle braking device according to claim 4, wherein, The fastening holes include a plurality of fastening holes arranged circumferentially along the insertion hole and spaced apart from each other.

6. The vehicle braking device according to claim 4, wherein, The fastening hole faces the flange extending from the drive unit.

7. The vehicle braking device according to claim 4, wherein, The first assembly also includes a seal disposed between the seat groove and the drive unit to prevent foreign matter from flowing into the drive unit.

8. The vehicle braking device according to claim 7, wherein, The seal is elastically deformable and is disposed along the inner circumferential surface of the seat groove.

9. The vehicle braking device according to claim 3, wherein, The second assembly extends from the assembly body in a direction parallel to the axial direction of the piston unit.

10. The vehicle braking device according to claim 9, wherein, The second assembly is coaxially arranged with the piston unit.

11. The vehicle braking device according to claim 3, wherein, The ring gear is fixed to the second assembly.

12. The vehicle braking device according to claim 11, wherein, The second assembly is inserted into the fastener.

13. The vehicle braking device according to claim 12, wherein, The fastener is fixed when its inner circumferential surface is pressed into the outer circumferential surface of the second assembly.

14. The vehicle braking device according to claim 12, wherein, The fastener is screwed to the second assembly.

15. The vehicle braking device according to claim 14, wherein, The second assembly has a plurality of first connecting holes disposed therein, and The fastener has multiple second connecting holes that are coaxially aligned with the first connecting hole. The second assembly and the fastener are connected to each other by fixing bolts that pass sequentially through the second connecting hole and the first connecting hole.

16. The vehicle braking device according to claim 11, wherein the transmission gear unit comprises: The first transmission gear rotates together with the output shaft of the drive unit; and The second transmission gear rotates together with the first transmission gear and meshes with and engages with the sun gear.

17. The vehicle braking device according to claim 16, wherein the diameter of the second transmission gear is larger than the diameter of the first transmission gear.

18. The vehicle braking device according to claim 2, further comprising a housing detachably connected to the assembly and covering the transmission gear unit and the planetary gear unit.

Images