Single-cylinder electronic parking brake

Abstract

The utility model discloses a single-cylinder electronic parking brake which comprises a driving mechanism assembly, a shell assembly, a transmission mechanism assembly, a friction plate assembly and a support assembly. The driving mechanism assembly outputs motor torque through a single output end; the shell assembly serves as an external structure of the brake, accommodates and fixes internal mechanical components, and is thinned at a stress concentration position; the transmission mechanism assembly comprises a single transmission mechanism, and motor torque output by the output end of the driving mechanism assembly is converted into axial motion to drive a piston to move. The friction plate assemblies comprise an inner friction plate assembly and an outer friction plate assembly which are driven by the piston to clamp the brake disc; the support assembly is connected with the shell assembly through bolts, fixes and supports the brake, and guides and limits path movement of a piston and a friction plate in the braking process. And the bracket assembly is slotted in an area where stress is not concentrated.

Description

Technical Field

[0001] This utility model belongs to the field of vehicle brake technology and relates to a single-cylinder electronic parking brake. Background Technology

[0002] With the rapid development of electrification technology, the application of new energy vehicles is gradually becoming more widespread. Especially in the automotive industry, the widespread adoption of electric drive systems ("three-electric systems") has become a crucial factor driving the electrification of vehicles. However, with the introduction of the three-electric systems, particularly the increased weight of the battery pack and motor system, the overall weight of new energy vehicles also increases. Studies suggest that for the same vehicle model, the introduction of the three-electric systems may lead to an increase in overall vehicle weight of approximately 200-300 kg, posing a significant challenge to the vehicle's energy efficiency and power performance.

[0003] The braking system, especially the electronic parking brake, accounts for a significant proportion of the overall chassis or unsprung weight of a car. Most existing electronic parking brakes employ a relatively traditional design, which has several significant drawbacks:

[0004] Heavy and energy-intensive: Traditional braking systems are often not designed with lightweighting and energy efficiency in mind, resulting in a heavy overall system and increased vehicle energy consumption. With the trend towards electrification, new energy vehicles have more stringent energy efficiency requirements, and heavy, energy-intensive braking designs can no longer meet market demands.

[0005] High cost: Existing electronic parking brake designs typically employ complex structures and materials, resulting in high manufacturing costs. This is particularly true in the production of new energy vehicles, where manufacturers need to balance performance, cost, and weight; existing braking solutions struggle to effectively reduce costs while maintaining braking performance.

[0006] Bulky structure and large space occupation: Most electronic parking brakes currently use a relatively bulky structural design, occupying a large amount of space. This not only increases the weight of the brake itself, but may also adversely affect the overall spatial layout of the vehicle, especially in the design of new energy vehicles, where the limited interior space places even stricter requirements on weight reduction and layout.

[0007] Therefore, the shortcomings of existing electronic parking brake designs in terms of weight, energy efficiency, and cost have become urgent technical problems to be solved in the development of new energy vehicles. In order to improve the energy efficiency of new energy vehicles, reduce overall weight, and lower energy consumption, there is an urgent need for a more compact and lightweight electronic parking brake design. Utility Model Content

[0008] To address the shortcomings of existing technologies, the purpose of this invention is to provide a single-cylinder EPB electronic parking brake; through structural optimization, a compact and lightweight design is achieved.

[0009] This utility model provides a single-cylinder EPB electronic parking brake, the brake comprising: a drive mechanism assembly, a housing assembly, a transmission mechanism assembly, a friction pad assembly, and a bracket assembly;

[0010] The drive mechanism assembly outputs motor torque through a single output end; a single motor is used as the drive source. The motor starts and outputs torque under set current and voltage conditions. The torque is amplified by the reduction gearbox and transmitted to the output shaft, and then drives the transmission mechanism assembly through a transmission chain or direct coupling.

[0011] The housing assembly serves as the external structure of the brake, housing and securing the internal mechanical components, and is thinned at stress concentration points; it also ensures that the braking system operates normally and reliably during vehicle operation and parking.

[0012] The transmission assembly includes a single transmission mechanism that converts the motor torque output from the drive assembly into axial motion, driving the piston. Specifically, through the cooperation and operation of the components, the transmission mechanism ensures that, under the control of the drive assembly, the rotational motion of the motor is effectively converted into axial thrust, thereby driving the piston and achieving precise driving and parking braking functions. The connection and cooperation between the components ensure the reliability, stability, and efficiency of the braking system.

[0013] The friction pad assembly includes two friction pad assemblies, inner and outer, which clamp the brake disc under the drive of the piston;

[0014] The bracket assembly is connected to the housing assembly by bolts to fix and support the brake, guide and restrict the path movement of the piston and friction pads during braking; the bracket assembly is slotted in areas where stress is not concentrated.

[0015] The housing assembly is provided with a housing cylinder bore;

[0016] The stress concentration locations include the bridge back and the chuck; the chuck abuts against the friction plate, the bridge back connects the cylinder bore and the chuck, and the bridge back and the chuck are subjected to force. By hollowing out the bridge back and / or the chuck, the weight of the housing assembly is reduced.

[0017] The transmission mechanism assembly is installed in the cylinder bore of the housing and includes: a retaining ring, a bushing, an O-ring seal, an upper gasket, a needle roller bearing, a lower gasket, an adjusting bolt, an adjusting nut, a piston, a piston seal, a dust cover, and a cage.

[0018] The adjusting bolt and the adjusting nut cooperate to convert the torque output by the motor in the drive mechanism assembly into axial output, driving the piston to push the friction plate and achieve the braking function; and / or,

[0019] The adjusting bolt is provided with a bolt base;

[0020] One end of the adjusting bolt is provided with a spline feature, and a retaining ring, bushing, O-ring seal, upper washer, needle roller bearing, and lower washer are sequentially fitted along the spline feature to the bolt base. After the fitting is completed, the upper end of the retaining ring does not exceed the lower edge of the spline feature, ensuring that the spline feature can be stably engaged with the spline at the output end of the drive mechanism assembly.

[0021] The piston has a hollow internal structure with at least two sets of reinforcing ribs symmetrically arranged on its inner wall. At least one set of opposing reinforcing ribs has a slot along the length of the piston. The end of the adjusting nut has a reinforcing feature that matches the shape and size of the reinforcing ribs. The adjusting nut is inserted into the internal space of the piston. The bottom of the piston's interior is machined with a concave hemisphere that matches the hemispherical shape of the end of the adjusting nut. A piston sealing ring is fitted onto the outer wall of the piston. A dust cover and a retainer are provided at the bottom. Grooves matching the piston sealing ring, the dust cover, and the retainer are opened at corresponding positions in the cylinder bore of the housing.

[0022] The retaining ring axial fixing and adjusting assembly has a limiting function;

[0023] The bushing is made of copper and has a low coefficient of friction; when the adjusting bolt rotates in the bushing, the bushing can reduce friction compared to the direct contact between the shaft and the ductile iron housing.

[0024] The O-ring is used for top sealing to prevent brake fluid leakage;

[0025] The upper shim is matched with the needle roller bearing and its function is to adjust the clearance, distribute the load evenly, prevent leakage, and provide buffer protection.

[0026] The needle roller bearing reduces friction, withstands radial loads, and provides high load-bearing capacity;

[0027] The dimensions, material, and function of the lower gasket are the same as those of the upper gasket.

[0028] The piston seal ring is made of rubber and can serve to seal and return to its original position.

[0029] The dust cover is made of rubber and can serve as a waterproof and dustproof cover.

[0030] The cage secures the dust cover during braking.

[0031] The friction plate assembly includes: an inner noise-dampening plate, an inner back plate, an inner friction plate, an outer friction plate, an outer back plate, and an outer noise-dampening plate;

[0032] The inner silencing plate, the inner back plate, and the inner friction plate together constitute the inner friction plate assembly, and the outer silencing plate, the outer back plate, and the outer friction plate together constitute the outer friction plate assembly;

[0033] The inner or outer silencing plate has a protruding portion extending beyond the friction plate at its lower part. The protruding portion wraps around the friction plate, securing the silencing plate to the back plate and the friction plate.

[0034] The inner silencing plate, the inner back plate, the inner friction plate or the outer silencing plate, the outer back plate, and the outer friction plate are connected and fixed together by protrusions provided in the structure and through holes that match the size and shape of the protrusions;

[0035] The inner or outer friction pad is the part of the friction pad assembly that directly contacts the brake disc. It is made of a material with a high coefficient of friction and is used to generate friction to achieve the braking function. The inner or outer backplate is located on the back of the inner and outer friction pads, respectively, providing a support structure for the friction pads to ensure that the friction material does not deform during braking and to evenly transmit braking force to the friction pads. The inner or outer noise-absorbing pad is attached to the inner and outer backplates, respectively, to absorb and reduce noise and vibration generated during braking and improve braking comfort.

[0036] The thickness of the inner friction plate or the outer friction plate is approximately 9-12 mm;

[0037] In one specific embodiment, the thickness of the inner friction plate and the outer friction plate is 7 mm.

[0038] The U-shaped clamp of the bracket assembly includes stress-free areas on both sides, and grooves are provided therein;

[0039] The bracket assembly is connected to the housing assembly by bolts, which fixes and supports the brake, guides the piston and friction pads to move along the correct path during braking, and restricts their unnecessary movement.

[0040] This utility model also provides a method for braking using the above-mentioned single-cylinder electronic parking brake, the method comprising the following steps:

[0041] Step 1: Initiate braking command

[0042] When the driver presses the brake pedal or the parking button, the electronic control unit (ECU) receives the command and begins braking.

[0043] Step 2: Generating braking force

[0044] Service brake: The hydraulic system generates pressure, which pushes the piston outward to clamp the friction pads and brake disc, thereby achieving deceleration or stopping.

[0045] Parking brake: The motor drives the adjusting bolt to rotate, pushing the piston to move outward, clamping the friction pads and brake disc to achieve parking brake.

[0046] Step 3: Maintain braking.

[0047] Service brake holding: The hydraulic system continuously maintains pressure to keep the brakes in place.

[0048] Parking brake holding: Adjust the bolts and nuts to lock and keep the friction pads clamped to the brake disc.

[0049] Step 4: Release the brakes

[0050] When the driver releases the brake or releases the parking command, the piston retracts, the friction pads release the brake disc, and the brake is released.

[0051] Step 5: System Reset

[0052] All components returned to their initial positions, ready for the next braking action.

[0053] The beneficial effects of this utility model include: the electronic parking brake caliper of this utility model has significant advantages in terms of compact structure, lightweight, and reduced cost; the compact design of the caliper structure allows it to adapt more flexibly to the wheel-side arrangement of different vehicle models, providing greater design space and higher integration; compared with traditional calipers, the lightweight design of this utility model caliper reduces its overall weight, significantly reducing the burden on the vehicle under the same cylinder diameter and brake disc thickness conditions, which helps to improve the energy efficiency and range of new energy vehicles; the optimized design and material selection reduce the production cost of the caliper, effectively reducing manufacturing costs and providing new energy vehicle manufacturers with a more competitive cost advantage. In one specific embodiment, when using the same cylinder diameter, the brake in this utility model weighs 4.5 kg, while that in the prior art weighs approximately 5.2 kg. Attached Figure Description

[0054] To more clearly illustrate the technical solutions in the embodiments of this utility model or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this utility model. For those skilled in the art, other drawings can be obtained from these drawings without creative effort.

[0055] Figure 1 This is a schematic diagram of the overall three-dimensional structure of the brake of this utility model.

[0056] Figure 2 This is an exploded view of the overall structure of this utility model.

[0057] Figure 3 This is an exploded view of the transmission mechanism assembly structure of this utility model.

[0058] Figure 4 This is a structural diagram of the housing assembly of this utility model.

[0059] Figure 5 This is a schematic diagram of the friction plate assembly of this utility model.

[0060] Figure 6 This is a three-dimensional view of the piston structure of this utility model.

[0061] Figure 7 This is a schematic diagram of the adjusting nut insertion piston structure of this utility model and a cross-sectional view of the section in the AA direction.

[0062] Figure 8 This is a schematic diagram of the bracket assembly structure of this utility model.

[0063] Figure 9 This is a schematic diagram of the overall structure of the brake of this utility model from another angle.

[0064] In the diagram, 1-drive mechanism assembly, 2-housing assembly, 3-transmission mechanism assembly, 3.1-retaining ring, 3.2-shaft sleeve, 3.3-O-ring seal, 3.4-upper gasket, 3.5-needle roller bearing, 3.6-lower gasket, 3.7-adjusting bolt, 3.8-adjusting nut, 3.9-piston, 3.10-piston seal, 3.11-dust cover, 3.12-cage, 4-friction plate assembly, 4.1-inner silencer plate, 4.2-inner back plate, 4.3-inner friction plate, 4.4-outer friction plate, 4.5-outer back plate, 4.6-outer silencer plate, 5-bracket assembly. Detailed Implementation

[0065] The utility model will be further described in detail below with reference to the specific embodiments and accompanying drawings. Except for the content specifically mentioned below, the processes, conditions, and experimental methods for implementing this utility model are all common knowledge and general knowledge in the field, and this utility model has no particular limitations.

[0066] This utility model is a collection of technical means to solve the problems of heavy weight and high cost of traditional electronic parking calipers. The design scheme further reduces the cost of parts and the weight of the entire wheel end by optimizing the structural features of the caliper's components and the price and manufacturing process of the components, thereby achieving the requirement of lightweighting.

[0067] In the process of realizing this utility model, stress analysis of the structure, including the housing assembly and the bracket assembly, will be performed using NX software.

[0068] The optimized parts of this utility model mainly involve the housing assembly 2 of the brake caliper, the bracket assembly 5, the piston 3.9 in the transmission mechanism assembly, the adjustment components (including the adjustment bolt 3.7, the adjustment nut 3.8, etc.) and the friction plate assembly 4.

[0069] The axial length of housing assembly 2 defines the overall height of the caliper, therefore reducing the axial length of the housing assembly is crucial for structural optimization. By calculating the working extension length of the adjustment component and piston 3.9, plus system clearance and dimensional chain, the axial length of the housing cylinder bore is reasonably calculated, thus clarifying the axial length of housing assembly 2. Simultaneously, the external shape of housing assembly 2 also affects the overall weight. Through initial design of the housing appearance, combined with finite element structural strength analysis and topology analysis, the key areas of stress concentration can be identified, especially the bridge back and caliper features. Based on this stress information, materials with minimal impact on overall structural strength can be removed while ensuring component safety. If the stress in a certain area is significantly lower than the allowable stress of the material, the material thickness in that area can be appropriately reduced or a lower-density material can be used to achieve weight reduction. Topology optimization automatically generates the optimal material distribution scheme based on the given design space, boundary conditions, and load conditions. It abstracts the chassis structure into a model composed of finite elements, and through continuous iteration using mathematical algorithms, finds an optimal material distribution topology, thereby achieving caliper weight reduction.

[0070] Secondly, there is the piston 3.9. Piston 3.9 moves axially in conjunction with the adjusting assembly. Besides reducing the axial dimension, this design also optimizes the internal structure of the piston cylinder. In this invention, a four-rib design with grooves on both sides ensures the radial clearance between the adjusting assembly and the piston while also achieving weight reduction. The bottom of piston 3.9 and the head of adjusting nut 3.8 have spherical contact, resulting in a relatively uniform stress distribution around the contact point. Compared to planar contact, where stress tends to concentrate at the edges of the contact area under pressure, leading to excessive local stress, spherical contact, due to its curved surface, allows pressure to spread more evenly across the contact surface. Spherical contact reduces excessive fatigue and damage to local materials during parking clamping, extending the service life of the parts.

[0071] The thickness of the friction pads and brake discs affects the height of the bracket assembly. With the widespread use of electric vehicles, energy recovery systems greatly contribute to the thinning of the friction pads, primarily by reducing the frequency of use and lowering the operating temperature of the friction pads. When the energy recovery system is working, it can share some of the braking load, converting the vehicle's kinetic energy into stored electrical energy. This reduces the frequency of use of the caliper friction pads and lowers their operating temperature, thus reducing wear and slowing down the rate of friction pad thinning. Therefore, this invention uses a friction pad thinning solution, resulting in a shorter axial length of the caliper assembly compared to existing technologies. Furthermore, by slotting the stress-dissipated areas on both sides of the U-shaped caliper body in the bracket assembly, unnecessary material is removed, making it lighter. Simultaneously, due to the thinning of the friction pads, the bracket also becomes thinner; in one specific embodiment, the bracket thins as the friction pads are thinned.

[0072] In one specific implementation, the friction plate and piston assembly are thinned by 10 mm, thus shortening the housing by 10 mm.

[0073] Furthermore, in actual implementation, the manufacturing process of the parts for the single-cylinder EPB electronic parking brake of this utility model has been optimized, reducing the cost of the parts.

[0074] Example 1

[0075] A schematic diagram of the electronic parking brake structure described in this utility model is shown below. Figure 1 and 2 As shown, the electronic parking brake consists of 5 parts, including drive mechanism assembly 1, housing assembly 2, transmission mechanism assembly 3, bracket assembly 5, and friction plate assembly 4.

[0076] This invention aims to design a compact and lightweight caliper, such as... Figure 4 and Figure 7 The brake housing assembly 2 and bracket assembly 5 were optimized in terms of shape characteristics through finite element analysis and other methods, achieving lightweight design while meeting strength requirements. For example... Figure 6 The piston 3.9, through a shortened axial length and internal feature design, along with several reinforcing ribs, achieves reduced overall weight while maintaining strength. The bottom of the piston 3.9 and the head of the adjusting nut 3.8 have spherical contact, resulting in relatively uniform stress distribution around the contact point. This spherical contact reduces excessive fatigue and damage to localized materials during parking clamping, extending the component's service life. Figure 5 The friction plate has a specially designed sound-absorbing plate that is pasted on the surface of the friction plate. The sound-absorbing plate is wrapped around the back plate and sandwiched between the friction plate and the bracket for sliding between the friction plate and the bracket.

[0077] Specifically, this embodiment provides a single-cylinder electronic parking brake, such as... Figure 9 As shown, the brake includes: a drive mechanism assembly 1, a housing assembly 2, a transmission mechanism assembly 3, a friction plate assembly 4, and a bracket assembly 5;

[0078] The drive mechanism assembly 1 outputs motor torque through a single output end;

[0079] The housing assembly 2 serves as the external structure of the brake, housing and fixing the internal mechanical components, and is thinned at stress concentration points;

[0080] The transmission mechanism assembly 3 includes a single transmission mechanism that converts the motor torque output from the output end of the drive mechanism assembly 1 into axial motion to drive the piston.

[0081] The friction plate assembly 4 includes two friction plate assemblies, inner and outer, which clamp the brake disc under the drive of the piston;

[0082] The bracket assembly 5 is connected to the housing assembly 2 by bolts, which fixes and supports the brake, guides and restricts the path movement of the piston and friction pads during braking; the bracket assembly 5 is slotted in areas where stress is not concentrated.

[0083] The drive mechanism assembly 1 includes a motor and a reduction gearbox. The torque output by the motor is amplified by the reduction gearbox and transmitted to the output shaft, and drives the transmission mechanism assembly 3 through a transmission chain or direct coupling.

[0084] The housing assembly 2 is provided with a housing cylinder bore; and / or,

[0085] The diameter of the cylinder bore in the housing is 48 mm; and / or,

[0086] In housing assembly 2, the stress concentration locations include the bridge back and the claw; the bridge back and / or the claw are hollowed out;

[0087] The transmission mechanism assembly 3 is installed in the cylinder bore of the housing, such as Figure 3 As shown, it includes: retaining ring 3.1, bushing 3.2, O-ring seal 3.3, upper gasket 3.4, needle roller bearing 3.5, lower gasket 3.6, adjusting bolt 3.7, adjusting nut 3.8, piston 3.9, piston seal ring 3.10, dust cover 3.11, and cage 3.12.

[0088] The adjusting bolt 3.7 and the adjusting nut 3.8 cooperate to convert the torque output by the motor in the drive mechanism assembly 1 into axial output, driving the piston 3.9 to push the friction plate and achieve the braking function; and / or,

[0089] A bolt base is provided on the adjusting bolt 3.7;

[0090] One end of the adjusting bolt 3.7 is provided with a spline feature. A retaining ring 3.1, a bushing 3.2, an O-ring seal 3.3, an upper washer 3.4, a needle roller bearing 3.5, and a lower washer 3.6 are sequentially fitted along the spline feature to the bolt base. After the fitting is completed, the upper end of the retaining ring 3.1 does not exceed the lower edge of the spline feature, ensuring that the spline feature can be stably engaged with the spline at the output end of the drive mechanism assembly 1.

[0091] The piston 3.9 has a hollow internal structure, with at least two sets of reinforcing ribs symmetrically arranged on its inner wall. At least one set of opposing reinforcing ribs has a slot along the length of the piston. The end of the adjusting nut 3.8 has a reinforcing feature that matches the shape and size of the reinforcing ribs. The adjusting nut 3.8 is inserted into the internal space of the piston 3.9. The bottom of the piston 3.9 has a concave hemisphere that matches the hemispherical shape of the end of the adjusting nut 3.8. A piston sealing ring 3.10 is fitted onto the outer wall of the piston 3.9. A dust cover 3.11 and a retainer 3.12 are provided at the bottom. Grooves matching the piston sealing ring 3.10, the dust cover 3.11, and the retainer 3.12 are opened at corresponding positions in the cylinder bore of the housing.

[0092] The friction plate assembly 4 includes: an inner noise-absorbing plate 4.1, an inner back plate 4.2, an inner friction plate 4.3, an outer friction plate 4.4, an outer back plate 4.5, and an outer noise-absorbing plate 4.6;

[0093] The inner silencing plate 4.1, the inner back plate 4.2, and the inner friction plate 4.3 together form the inner friction plate assembly, and the outer silencing plate 4.6, the outer back plate 4.5, and the outer friction plate 4.4 together form the outer friction plate assembly.

[0094] The lower part of the inner silencing plate 4.1 or the outer silencing plate 4.6 is provided with a protruding portion that extends beyond the friction plate, and the protruding portion wraps around and fixes the friction plate.

[0095] The inner silencing plate 4.1, the inner back plate 4.2, the inner friction plate 4.3 or the outer silencing plate 4.6, the outer back plate 4.5, and the outer friction plate 4.4 are connected and fixed together by protrusions and through holes that match the size and shape of the protrusions.

[0096] The thickness of the inner friction plate 4.3 and the outer friction plate 4.4 is 9-12 mm.

[0097] The left and right sides of the U-shaped clamp body of the bracket assembly 5 are stress-free areas, and grooves are provided there, such as... Figure 8 As shown.

[0098] Example 2

[0099] In one specific implementation, the main functions of housing assembly 2 include the following:

[0100] 1) Support and fix internal components

[0101] The housing assembly 2 provides structural support and fixation for the internal components of the parking brake, including components such as pistons, transmission mechanisms (e.g., adjusting bolts and adjusting nuts), friction pad assemblies, motor drive devices, and reduction gearboxes. The housing assembly 2 ensures that all internal components maintain their relative positions during operation by providing a robust external frame, preventing displacement or loosening during braking.

[0102] 2) Contains hydraulic system

[0103] The housing assembly 2 is designed with an internal housing bore, which serves as the main container for the hydraulic system, holding the brake fluid and transmitting hydraulic pressure. The hydraulic system transmits hydraulic fluid through channels and chambers within the housing assembly. This hydraulic fluid acts on pistons, pushing them outward to press against the friction pads, thus achieving vehicle braking. The housing assembly design also ensures the hydraulic fluid is sealed, preventing leakage and maintaining the stability and efficiency of the hydraulic system.

[0104] 3) Protect internal components

[0105] The housing assembly 2 protects the internal mechanical and hydraulic components from external environmental factors (such as mud, rain, dust, chemicals, etc.) and physical impacts. The housing is typically made of high-strength materials (such as cast iron, aluminum alloy, or steel) capable of withstanding external physical impacts and pressures, while also possessing corrosion resistance and high-temperature resistance. This protection extends the service life of the brake components and ensures the brake's normal operation in harsh environments.

[0106] 4) Heat dissipation function

[0107] During braking, a large amount of heat is generated between the friction pads and the brake disc. The housing assembly 2 can also help dissipate this heat quickly to prevent the braking system from overheating. Since the housing assembly 2 is usually designed with heat sinks or uses materials with good thermal conductivity, it helps to dissipate the heat generated when the internal components are working.

[0108] 5) Force transmission and distribution

[0109] The housing assembly 2 is a crucial medium for transmitting braking force and parking force throughout the braking system. Through its internal structural design (such as the housing bore and mounting bracket), the housing assembly 2 can evenly distribute the forces generated during braking to components such as the friction pads, pistons, and transmission mechanisms. This ensures that the pressure on each component is within its design range, thereby improving the efficiency and stability of the braking system.

[0110] 6) Installation and Integration

[0111] The housing assembly 2 provides a mounting interface for securing the brake to the vehicle's suspension system or axle; through precise mounting holes and bracket design, the housing assembly ensures that the brake can be securely mounted to the vehicle's chassis or wheel support structure, maintaining its precise alignment with the brake disc.

[0112] In one specific implementation, the adjusting bolt 3.7 in the transmission mechanism is used to convert the rotational motion of the motor into axial thrust, and to move the piston by cooperating with the adjusting nut; the adjusting nut 3.8 and the adjusting bolt 3.7 are threaded together, and the axial displacement is achieved by the rotational motion of the adjusting bolt 3.7, which pushes the piston 3.9 to move outward; the piston 3.9 is pushed by the axial thrust of the adjusting nut 3.8 to push the friction plate against the brake disc, thereby achieving braking.

[0113] The adjusting bolt 3.7 is connected to the output shaft of the reduction gearbox. When the motor drives it, the adjusting bolt 3.7 rotates and drives the adjusting nut 3.8 to move along its thread. The axial movement of the adjusting nut 3.8 generates a thrust on the piston 3.9, which pushes the piston 3.9 to move outward.

[0114] The adjusting nut 3.8 directly pushes the piston 3.9 through its axial displacement, causing the piston 3.9 to move outward, press against the friction plate, and generate braking force;

[0115] In practical applications, the transmission mechanism is used in electronic parking brakes as follows:

[0116] 1. Braking process:

[0117] When the electronic control unit (ECU) receives a braking command, the motor drive starts, and the output torque is transmitted to the adjusting bolt 3.7 through the reduction gearbox. The adjusting bolt 3.7 rotates, and the threaded structure drives the adjusting nut 3.8 to move axially.

[0118] 2. Generates axial thrust:

[0119] The axial movement of the adjusting nut 3.8 generates thrust, pushing the piston 3.9 outward. During this process, the needle roller bearing 3.5 reduces friction between the adjusting bolt 3.7 and the adjusting nut 3.8, ensuring smooth rotational movement.

[0120] 3. Piston movement and generation of braking force:

[0121] Piston 3.9 moves outward under the action of adjusting nut 3.8, pressing the inner and outer friction pads into contact with the brake disc, generating friction force, thereby realizing the vehicle's braking or parking function.

[0122] 4. Maintaining and releasing the braking state:

[0123] When the braking force reaches the preset parking force (e.g., 28000N), the adjusting bolt 3.7 and adjusting nut 3.8 stop moving and remain in a mechanically locked state, ensuring that the friction pads clamp the brake disc and achieve parking braking.

[0124] When the brake needs to be released, the motor rotates in the reverse direction, the adjusting bolt 3.7 rotates in the reverse direction, the adjusting nut 3.8 moves axially in the reverse direction, the piston 3.9 retracts, the friction pads release the brake disc, and the vehicle can move normally.

[0125] In one specific implementation, the main functions of the support assembly 5 include the following:

[0126] 1. Fix and support the brake.

[0127] The main function of the bracket assembly 5 is to fix the brake to the vehicle's suspension system or axle, ensuring that the brake and brake disc maintain the correct relative position.

[0128] The bracket assembly 5 provides a connection point to the vehicle mounting surface, typically secured to the axle or suspension system with bolts or other fasteners. During vehicle operation, the bracket assembly withstands braking forces and vibrations from the brakes, thus possessing sufficient strength and rigidity to ensure that the brakes do not shift or loosen.

[0129] 2. Absorbing and dispersing braking force

[0130] Brake assembly 5 is responsible for absorbing and dispersing the braking force and vibration generated during braking, reducing stress concentration in the braking system, and protecting other components.

[0131] When the brakes apply braking force, the frictional force generated between the brake disc and the friction pads is transmitted to the bracket assembly 5 through the caliper. The bracket assembly 5 must be able to effectively absorb these forces and distribute them evenly to the frame or suspension system to prevent fatigue damage caused by stress concentration.

[0132] 3. To guide and restrict the movement of the piston and friction plates.

[0133] The structural design of the bracket assembly 5 ensures that the piston 3.9 and friction pads move along the correct path during braking and limits their unnecessary movement.

[0134] The bracket assembly 5 acts as a guide within the caliper, ensuring that the piston 3.9 and the friction pads move along their designed axes during braking and release, without tilting or jamming. By providing this guiding function, the bracket assembly 5 ensures maximum contact area between the friction pads and the brake disc, improving braking efficiency and reducing uneven wear and friction pad wear.

[0135] 4. Provides installation and positioning functions.

[0136] The bracket assembly 5 provides mounting points and positioning functions for various components inside the caliper (such as piston 3.9, friction plates, and transmission mechanism), ensuring that these components function properly within their design scope.

[0137] These installation and positioning functions not only simplify the assembly and maintenance process of the brakes, but also ensure the coordinated operation of the components during braking, thereby improving the overall reliability and safety of the braking system.

[0138] 5. Heat dissipation function

[0139] The bracket assembly 5 helps dissipate the heat generated during braking, preventing the braking system from overheating and maintaining the stability of braking performance.

[0140] During braking, the friction between the friction pads and the brake disc generates a large amount of heat. The bracket assembly 5 can help dissipate the heat quickly through its material selection and design optimization, preventing heat accumulation that could lead to a decrease in braking performance (such as heat fade).

[0141] The design of bracket assembly 5 typically considers heat sinks or other heat dissipation structures to increase heat dissipation area and airflow, thereby enhancing heat dissipation efficiency.

[0142] 6. Improve the durability of the braking system

[0143] The bracket assembly 5 extends the service life of other components in the braking system through its structural design and material selection.

[0144] By providing stable support, guidance, and positioning functions, the bracket assembly 5 reduces abnormal wear and fatigue damage to components during braking, thereby improving the durability of the entire braking system.

[0145] The bracket assembly 5 is typically designed using high-strength materials (such as alloy steel or aluminum alloy), which have good fatigue resistance and corrosion resistance, making them suitable for long-term use under complex vehicle operating conditions.

[0146] In the description of this utility model, it should be noted that the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inner", "outer", etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing this utility model and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this utility model.

[0147] In the description of this utility model, it should be noted that, unless otherwise explicitly specified and limited, the terms "installation," "connection," and "joining" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection of two components. Those skilled in the art can understand the specific meaning of the above terms in this utility model based on the specific circumstances.

[0148] Furthermore, when an element is referred to as being "on" another element, the element may be directly on the other element, or it may be indirectly on the other element with one or more intermediate elements inserted between them. Additionally, when an element is referred to as being "connected" to another element, the element may be directly connected to the other element, or it may be indirectly connected to the other element with one or more intermediate elements inserted between them.

[0149] The scope of protection of this utility model is not limited to the above embodiments. Any variations and advantages that can be conceived by those skilled in the art without departing from the spirit and scope of the utility model are included in this utility model and are protected by the appended claims.

Claims

1. A single-cylinder electronic parking brake, characterized in that, The brake includes: a drive mechanism assembly (1), a housing assembly (2), a transmission mechanism assembly (3), a friction plate assembly (4), and a bracket assembly (5); The drive mechanism assembly (1) outputs motor torque through a single output end; The housing assembly (2) serves as the external structure of the brake, housing and fixing the internal mechanical components, and is thinned at stress concentration points; The transmission mechanism assembly (3) includes a single transmission mechanism that converts the motor torque output from the output end of the drive mechanism assembly (1) into axial motion to drive the piston to move. The friction plate assembly (4) includes two friction plate assemblies, inner and outer, which clamp the brake disc under the drive of the piston; The bracket assembly (5) is connected to the housing assembly (2) by bolts to fix and support the brake, guide and restrict the path movement of the piston and friction pad during the braking process; the bracket assembly (5) is slotted in the stress-free area.

2. The brake as claimed in claim 1, characterized in that, The drive mechanism assembly (1) includes a motor and a reduction gearbox. The torque output by the motor is amplified by the reduction gearbox and transmitted to the output shaft, and drives the transmission mechanism assembly (3) through a transmission chain or direct coupling.

3. The brake as described in claim 1, characterized in that, The housing assembly (2) is provided with a housing cylinder bore; and / or, In the housing assembly (2), the stress concentration locations include the bridge back and the claw; the bridge back and / or the claw are hollowed out.

4. The brake as claimed in claim 1, characterized in that, The transmission mechanism assembly (3) is installed in the cylinder bore of the housing and includes: a retaining ring (3.1), a bushing (3.2), an O-ring seal (3.3), an upper gasket (3.4), a needle roller bearing (3.5), a lower gasket (3.6), an adjusting bolt (3.7), an adjusting nut (3.8), a piston (3.9), a piston seal (3.10), a dust cover (3.11), and a cage (3.12).

5. The brake as described in claim 4, characterized in that, The adjusting bolt (3.7) and the adjusting nut (3.8) cooperate to convert the torque output by the motor in the drive mechanism assembly (1) into axial output, driving the piston (3.9) to push the friction plate and realize the braking function; and / or, The adjusting bolt (3.7) is provided with a bolt base; One end of the adjusting bolt (3.7) is provided with a spline feature, and a retaining ring (3.1), a bushing (3.2), an O-ring seal (3.3), an upper washer (3.4), a needle roller bearing (3.5), and a lower washer (3.6) are sequentially sleeved and installed along the spline feature to the bolt base. After the sleeved installation is completed, the upper end of the retaining ring (3.1) does not exceed the lower edge of the spline feature, ensuring that the spline feature can be stably engaged with the spline at the output end of the drive mechanism assembly (1).

6. The brake as claimed in claim 4, characterized in that, The piston (3.9) has a hollow internal structure, with at least two sets of reinforcing ribs symmetrically arranged on its inner wall. At least one set of opposing reinforcing ribs has a slot along the length of the piston. The end of the adjusting nut (3.8) has a reinforcing feature that matches the shape and size of the reinforcing rib. The adjusting nut (3.8) is inserted into the internal space of the piston (3.9). The bottom of the piston (3.9) is machined with a concave hemisphere that matches the hemispherical shape of the end of the adjusting nut (3.8). A piston sealing ring (3.10) is fitted onto the outer wall of the piston (3.9). A dust cover (3.11) and a retainer (3.12) are provided at the bottom. Grooves matching the piston sealing ring (3.10), the dust cover (3.11), and the retainer (3.12) are opened at corresponding positions in the cylinder bore of the housing.

7. The brake as claimed in claim 4, characterized in that, The friction plate assembly (4) includes: an inner silencing plate (4.1), an inner back plate (4.2), an inner friction plate (4.3), an outer friction plate (4.4), an outer back plate (4.5), and an outer silencing plate (4.6); The inner silencing plate (4.1), the inner back plate (4.2), and the inner friction plate (4.3) together form the inner friction plate assembly, and the outer silencing plate (4.6), the outer back plate (4.5), and the outer friction plate (4.4) together form the outer friction plate assembly; The lower part of the inner silencing plate (4.1) or the outer silencing plate (4.6) is provided with a protruding part that extends beyond the friction plate, and the protruding part wraps around and fixes the friction plate.

8. The brake as claimed in claim 7, characterized in that, The inner silencing plate (4.1), the inner back plate (4.2), the inner friction plate (4.3) or the outer silencing plate (4.6), the outer back plate (4.5), and the outer friction plate (4.4) are connected and fixed together by protrusions provided in the structure and through holes that match the size and shape of the protrusions.

9. The brake as claimed in claim 7, characterized in that, The thickness of the inner friction plate (4.3) and the outer friction plate (4.4) is 9-12 mm.

10. The brake as claimed in claim 1, characterized in that, The U-shaped clamp of the bracket assembly (5) includes stress-free areas on both sides and has grooves.

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