Brake caliper of automobile

Abstract

The invention relates to the technical field of vehicle brake devices, in particular to an automobile brake caliper which comprises a caliper body and brake pads, 2N hydraulic cavities are formed in the caliper body, N is a positive integer, linear pistons are coaxially installed in the hydraulic cavities in a sliding mode, the two brake pads are arranged in the caliper body, and the linear pistons are coaxially installed in the hydraulic cavities in a sliding mode. The two brake pads are arranged on the left side and the right side of a wheel brake disc, the multiple linear pistons are symmetrically arranged on the left side and the right side of the brake disc, and the linear pistons are fixedly connected with the brake disc. According to the brake caliper, the second-type piston driven by the electromagnetism is arranged on the caliper body, a single hydraulic braking mode of a traditional brake caliper is converted into an electromagnetism and hydraulic cooperative braking composite mode, the braking response speed is increased, the braking force is increased, meanwhile, the braking dragging phenomenon caused by limited reset force of a sealing ring and rubber aging is avoided, and the service life of the brake caliper is prolonged. The consumption of vehicle endurance electric energy caused by braking dragging is reduced, and the energy utilization efficiency of the vehicle is improved.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of vehicle braking devices, in particular to a brake caliper of an automobile. BACKGROUND

[0002] The hydraulic brake caliper of the prior art mainly comprises a caliper body, a piston, a hydraulic chamber and brake pads. During braking, brake fluid is pressed into the hydraulic chamber to push the piston to clamp the brake pads against the brake disc, thereby generating friction to achieve braking. When the braking is released, the hydraulic pressure is removed, and the piston relies on the slight elastic deformation of its sealing ring to reset, so that the brake pads are separated from the brake disc. This passive reset mode has inherent defects. First, the reset force of the sealing ring is limited and decreases with the aging of the rubber, which easily leads to the brake pads failing to reset completely, resulting in continuous friction, i.e., the "braking drag" phenomenon. The braking drag not only aggravates the wear of the brake pads and the brake disc, but also generates unnecessary driving resistance. For a pure electric vehicle, which is crucial for the cruising range, the braking drag will directly lead to the unnecessary loss of electric energy and shorten the cruising range.

[0003] In addition, to meet the parking requirement, the vehicle usually needs to be equipped with an independent electronic parking system. Currently, the mainstream solution is to additionally integrate an electronic parking motor and a speed reduction mechanism on the rear wheel brake caliper, such as an EPB caliper, or in a few cases to use a cable type hand brake. Although the EPB caliper realizes electronic control, as an independent module attached to the traditional caliper, it leads to problems such as complex structure, weight increase, cost increase, and large space occupation.

[0004] Therefore, there is an urgent need in the art for an innovative brake caliper solution that can fundamentally solve the problem of braking drag and achieve high integration of basic braking and auxiliary functions to adapt to the development trend of new energy vehicles. SUMMARY

[0005] The present application relates to the technical field of vehicle braking devices, in particular to a brake caliper of an automobile.

[0006] To achieve the above-mentioned purpose, the present application provides the following technical solutions: The utility model provides a kind of brake caliper of car, including caliper body and brake pad, 2N hydraulic chambers are provided in the caliper body, N is positive integer, a plurality of the hydraulic chamber is coaxially slidingly installed with a type piston, two brake pads are provided in the caliper body, two brake pads are located on the left and right sides of wheel brake disc, a plurality of the piston of a type is symmetrically arranged on the left and right sides of brake disc, and the piston of a type is fixedly connected with brake disc;Specifically, a plurality of the hydraulic chamber two are a group of symmetrically arranged, and each group of hydraulic chamber is communicated, the side wall of the caliper body away from wheel is screw-connected with sleeve, the sleeve is slidingly connected with two type pistons, the end of the two type pistons away from brake disc is coaxially screw-connected with permanent magnet rod, the end of the sleeve away from brake disc is coaxially screw-connected with electromagnet, the end of the permanent magnet rod away from brake disc extends to the outside of electromagnet, the electromagnet is electrically connected with vehicle-mounted ECU by H bridge circuit, the inside of the sleeve is communicated with a group of symmetrically arranged hydraulic chambers, and the hydraulic chamber not communicated with the inside of sleeve is communicated with the brake hydraulic system of vehicle by hydraulic pipe.

[0007] By setting two type pistons on caliper body, when braking, vehicle-mounted ECU controls electromagnet to be electrified, electromagnet generates repulsive magnetic field force with permanent magnet rod, the magnetic field force generated by electromagnet pushes permanent magnet rod to move towards brake disc, permanent magnet rod pushes two type pistons to move towards brake disc, the inside of sleeve is communicated with a group of symmetrically arranged hydraulic chambers, the movement of two type pistons towards brake disc improves the hydraulic pressure in the group of hydraulic chambers, and then pushes the piston of a type fixedly connected with brake disc to move towards brake disc, so that brake pad clamps brake disc to realize braking, so as to improve the response speed of brake, and improve the extrusion force of brake pad on brake disc and brake intensity, so as to improve the brake intensity of brake caliper.

[0008] When braking is released, vehicle-mounted ECU controls the current direction through electromagnet, electromagnet generates attractive magnetic field force to permanent magnet rod, the magnetic field force generated by electromagnet pushes permanent magnet rod to move away from brake disc, at this time, two type pistons follow permanent magnet rod to move away from brake disc, the hydraulic pressure in sleeve reduces, two type pistons reset under the action of hydraulic counterforce, drive the piston of a type to reset, so that brake pad is separated from brake disc, two type pistons are directly communicated with communicated piston chamber, the hydraulic pressure in sleeve drops faster than the hydraulic pressure drop speed of brake hydraulic system of vehicle, so as to accelerate the reset speed of brake pad, avoid the brake drag problem caused by limited reset force of sealing ring and rubber aging in traditional brake caliper, and reduce the consumption of brake drag on vehicle endurance electric energy.

[0009] By setting the auxiliary electric drive brake structure on the basic brake structure of the traditional brake caliper, the flexible adjustment of the brake force and the brake speed is realized by adjusting the energization parameters of the electromagnet and the control strategy of the H-bridge circuit, so as to meet the brake requirements in different driving scenes; when the vehicle is normally running, the vehicle-mounted ECU disconnects the current of the electromagnet, and the permanent magnet rod is adsorbed in the electromagnet under the action of the magnetic force, so as to avoid the consumption of the extra electric energy of the vehicle by the electromagnet when the vehicle is normally running, and to ensure that the endurance electric energy of the vehicle is not consumed.

[0010] Preferably, the conical frustum end of the second type of piston is adjacent to the brake disc, a plurality of mounting holes are formed in the outer side wall of the sleeve, the plurality of mounting holes are arranged in a ring shape, and the plurality of mounting holes penetrate through the inner and outer sides of the sleeve, a limiting slide rod is slidably connected in the mounting hole, the two ends of the plurality of limiting slide rods extend to the inner and outer sides of the sleeve respectively, a tapered surface is arranged on the side of the end of the limiting slide rod extending into the sleeve and facing the electromagnet, the taper of the conical frustum end of the second type of piston is the same as that of the tapered surface, a sealing tube is threadedly connected to the outer side wall of the sleeve, the inner side wall of the sealing tube, the outer side wall of the sleeve and the side wall of the caliper body form a sealing cavity, a piston ring is coaxially arranged in the sealing cavity, the inner and outer sides of the piston ring are slidably connected with the outer side wall of the sleeve and the inner side wall of the sealing tube respectively, an oil inlet is formed in the side wall of the sealing tube, the oil inlet penetrates through the inner and outer sides of the sealing tube, the oil inlet is arranged on the side wall of the piston ring away from the brake disc, the oil inlet is in communication with the brake hydraulic system of the vehicle through a hydraulic pipe, a plurality of wedge-shaped blocks are arranged on the side wall of the piston ring close to the brake disc, the plurality of wedge-shaped blocks are inclined toward the outer side of the sealing tube, an embedding groove is formed in the side wall of the end of the plurality of limiting slide rods extending to the outside of the sleeve, the wedge-shaped surface of the wedge-shaped block is slidably connected with the embedding groove, and a limiting groove is coaxially formed in the conical frustum side wall of the second type of piston.

[0011] By setting the limiting slide rod on the side wall of the sleeve, and setting the limiting groove on the side wall of the second type of piston near the brake disc, when the vehicle is running normally, the second type of piston is in the initial position under the adsorption of the permanent magnet rod and the electromagnet, ensuring the stability of the second type of piston when the vehicle is running normally, preventing it from moving accidentally due to vehicle vibration or external factors, at this time, the embedded groove of the limiting slide rod and the wedge block on the piston ring are in a free and non-stressed state. When the vehicle is braking during driving, the electromagnet generates a magnetic field force to push the second type of piston to move towards the brake disc direction, the conical end of the second type of piston will gradually extrude the taper surface of the limiting slide rod, so that the limiting slide rod moves to the outside of the sleeve, at the same time, the piston ring moves towards the brake disc under the action of hydraulic pressure, the wedge block on the piston ring slides with the embedded groove of the limiting slide rod, the wedge block pushes the limiting slide rod to move outward to the sleeve, cooperating with the linear motion of the second type of piston to convert into radial movement of the limiting slide rod, further improving the brake response speed. When the brake is released, with the change of the direction of the magnetic field force of the electromagnet, the second type of piston returns under the attraction of the permanent magnet rod, the limiting groove moves away from the brake disc, after passing through the vertical projection range of the limiting slide rod, the limiting slide rod returns under the action of hydraulic pressure in the sleeve, the piston ring and the wedge block return under the action of hydraulic pressure in the sealed cavity, the system returns to the initial state, ready for the next brake, realizing precise control and efficient return during braking, effectively solving the brake drag problem existing in the traditional brake caliper, reducing the consumption of vehicle endurance power caused by brake drag.

[0012] Further, when the vehicle is running and the brake hydraulic system of the vehicle fails, the vehicle ECU detects the failure of the brake hydraulic system, the vehicle ECU alerts the driver through the instrument panel signal, the driver steps on the brake pedal, and the vehicle ECU detects the brake signal. Since the brake hydraulic system fails at this time, there is no hydraulic pressure in the hydraulic chamber that is not communicated with the inside of the sleeve. At this time, the electromagnet is energized to generate a magnetic field force to push the second type of piston to move towards the brake disc. The conical end of the second type of piston will gradually extrude the conical surface of the limiting slide rod, so that the limiting slide rod moves to the outside of the sleeve. At the same time, the limiting slide rod moves to the outside of the sleeve under the action of the hydraulic pressure in the sleeve. When the second type of piston moves towards the brake disc, the hydraulic pressure in the hydraulic chamber communicated with the inside of the sleeve rises, the first type of piston in the hydraulic chamber communicated with the inside of the sleeve moves towards the brake disc, and pushes the brake pad to move towards the brake disc, thereby realizing the brake effect. Although the braking force is weaker than the normal braking force of the vehicle, it still ensures the braking ability of the vehicle when the brake hydraulic system of the vehicle fails, thereby ensuring the safety of the vehicle and the people in the vehicle. Further, since there is no hydraulic pressure in the sealing chamber at this time, the piston disc does not move towards the brake disc, the wedge-shaped block cannot push the limiting slide rod to move to the outside of the sleeve, the limiting groove moves towards the brake disc along with the second type of piston, and the limiting slide rod slides into the limiting groove after the limiting groove moves to the vertical projection range of the limiting slide rod. Thus, the limiting slide rod limits the movement of the second type of piston away from the brake disc, thereby maintaining the braking effect and avoiding the loss of braking force of the vehicle after the driver releases the brake pedal, further ensuring the safety of the vehicle and the people in the vehicle.

[0013] Preferably, the permanent magnet rod comprises a mounting section and a magnet section, the mounting section is fixedly connected with the magnet section, and the mounting section is threadedly connected with the second type of piston, and the magnet section extends to the outside of the electromagnet at the end away from the mounting section. The magnet section is made of neodymium magnetic material.

[0014] By setting the permanent magnet rod as a mounting section and a magnet section, and using neodymium magnetic material with high magnetic performance for the magnet section, a stable and strong magnetic field can be generated to provide reliable and lasting driving force for the second type of piston. The mounting section is responsible for stable connection with the second type of piston to ensure that there is no loosening or falling between the permanent magnet rod and the second type of piston during braking, thereby ensuring the stability and reliability of the entire braking system. At the same time, this segmented design also facilitates subsequent maintenance and replacement. If the magnet section has problems such as reduced magnetism due to long-term use or other reasons, only the magnet section needs to be replaced, without the need to replace the entire permanent magnet rod, thereby reducing maintenance costs.

[0015] Preferably, a resilient ring is coaxially arranged in the sealing chamber, the inner and outer sidewalls of the resilient ring are fixedly connected with the outer sidewall of the limiting slide rod and the inner sidewall of the sealing tube respectively, and the resilient ring has a hollow structure.

[0016] By setting the elastic ring in the sealed cavity, when the two type pistons move to drive the limiting slide rod to move radially, the elastic ring can be elastically deformed to provide certain buffer and rebound force for the movement of the limiting slide rod; during braking, when the limiting slide rod is pushed by the conical end of the two type pistons or the wedge-shaped block on the piston ring to move outward of the sleeve, the elastic ring is compressed and stores elastic potential energy; when the brake is released, the two type pistons return, and the limiting slide rod needs to return, the elastic ring releases the elastic potential energy to help the limiting slide rod quickly return to the initial position, ensuring that the limiting slide rod can accurately cooperate with the two type pistons and the piston ring during the next braking, and the hollow structure of the elastic ring has certain flexibility and can maintain good elastic performance under different pressures and deformation conditions, and is not prone to elastic failure after long-term use, further improving the reliability and durability of the brake caliper and effectively ensuring the stable operation of the brake system under various working conditions.

[0017] Preferably, a heat dissipation pipe is coaxially sleeved on the outer side wall of the electromagnet, and a plurality of circumferentially distributed heat dissipation fins are arranged on the outer side wall of the heat dissipation pipe.

[0018] By arranging the heat dissipation fins on the outer side wall of the electromagnet, the electromagnet will heat up due to the magnetic field force generated by the current during braking. If the heat cannot be dissipated in time, the temperature of the electromagnet will rise, which will affect its magnetic properties and service life. The arrangement of the heat dissipation pipe and the heat dissipation fins can effectively increase the heat dissipation area of the electromagnet and speed up the heat dissipation speed. The heat dissipation pipe is in close contact with the electromagnet, which can quickly conduct the heat generated by the electromagnet to the heat dissipation fins. The heat dissipation fins exchange heat with the surrounding air through their large surface area, dissipate heat to the air, thereby reducing the temperature of the electromagnet, ensuring that it is always in good working condition, and improving the overall performance and reliability of the brake caliper.

[0019] Preferably, the pressure receiving area of the one type piston is S1, the pressure receiving area of the conical end of the two type piston is S2, and 2.5·S2≤S1≤3.5·S2.

[0020] The area ratio design can realize optimal hydraulic transmission effect in the braking process, when the electromagnet is powered to drive the movement of the second type of piston, the second type of piston is pressed by the area S2 and the hydraulic pressure in the hydraulic chamber, which generates the force to push the first type of piston, due to the proportional relationship between S1 and S2, the first type of piston can obtain sufficient and appropriate force to push the brake pad to clamp the brake disc, so as to realize efficient braking. If S1 is less than 2.5*S2, the hydraulic transmission generated by the movement of the second type of piston to the first type of piston may not provide sufficient braking force, resulting in poor braking effect, which may not be able to stop the vehicle in time in the case of emergency braking, increasing the risk of accidents. If S1 is greater than 3.5*S2, although the braking force may increase, the excessive braking force may cause the brake to be too sharp, causing discomfort to the vehicle passengers, and may also cause excessive wear to the brake pad and brake disc, shorten its service life and increase the use cost; the proportional design avoids excessive hydraulic fluctuation caused by unreasonable area ratio, thereby ensuring the uniformity and consistency of the braking force, enabling the driver to more accurately control the braking process, improving the safety and comfort of driving.

[0021] Preferably, a filter screen is arranged between the sleeve and the communicating hydraulic chamber, and the filter screen is fixedly installed at one end of the sleeve close to the brake disc.

[0022] By arranging the filter screen between the sleeve and the hydraulic chamber, during the braking process, metal particles are easily generated due to the rigid friction between the second type of piston and the limiting slide rod, and the hydraulic oil flows between the sleeve and the hydraulic chamber, the filter screen can effectively intercept impurities, metal particles and wear debris generated during braking in the hydraulic oil, and if the impurities enter the hydraulic chamber, they may block the hydraulic channel, affect the normal flow of the hydraulic oil, and thus reduce the hydraulic transmission efficiency of the brake caliper, resulting in slow braking response or even brake failure, and the presence of the filter screen can ensure that the hydraulic oil entering the hydraulic chamber is clean, guaranteeing the smooth operation of the hydraulic system and improving the reliability and stability of the brake caliper; at the same time, the filter screen can also prevent impurities from causing wear to the first type of piston, the second type of piston and other precision components, prolonging the service life of these components, reducing the maintenance cost and failure rate of the brake caliper, and further ensuring the braking safety of the vehicle.

[0023] Compared with the prior art, the present application has the following advantages: 1. The application converts the single hydraulic brake mode of the traditional brake caliper into a composite mode of electromagnetic and hydraulic cooperative braking by setting a two-type piston driven by electromagnet on the caliper body, improves the brake response speed and brake force, avoids the brake drag phenomenon caused by the limited reset force of the sealing ring and the aging of rubber, reduces the consumption of vehicle endurance power caused by brake drag, and improves the energy utilization efficiency of the vehicle.

[0024] 2. The application sets a limiting slide rod on the side wall of the sleeve, and sets a limiting groove on the side wall of the two-type piston close to the brake disc, utilizes the taper surface cooperation of the two-type piston with the limiting slide rod and the sliding cooperation of the wedge-shaped block on the piston ring with the embedded groove of the limiting slide rod, effectively converts the linear motion of the two-type piston into the radial movement of the limiting slide rod, further improves the brake response speed, and realizes accurate and efficient return of the system when the brake is released, effectively solves the brake drag problem of the traditional brake caliper, and guarantees the braking performance and endurance of the vehicle.

[0025] 3. The application sets a fault emergency brake mechanism, when the vehicle brake hydraulic system fails, the vehicle ECU can detect the fault and alert the driver through the instrument panel signal, the driver steps on the brake pedal, the electromagnet is powered to generate a magnetic field force to drive the two-type piston to move, to achieve a certain degree of brake effect, guarantee the braking ability of the vehicle when the brake hydraulic system fails, at the same time, the limiting slide rod slides into the limiting groove to limit the return of the two-type piston, avoids the vehicle losing braking force after the driver releases the brake pedal, and ensures the safety of the vehicle and the people inside. DETAILED DESCRIPTION

[0026] Figure 1 It is the overall structure diagram of the automobile brake caliper of the application; Figure 2 It is the front view of the automobile brake caliper of the application; Figure 3 It is Figure 2 the full cross-sectional view at A-A; Figure 4 It is Figure 3 the local enlarged view at B; Figure 5 It is Figure 3 the full cross-sectional view at C-C; Figure 6 It is the state diagram of the two-type piston and the limiting slide rod when the vehicle is parking brake; Figure 7 It is the state diagram of the two-type piston and the limiting slide rod when the vehicle is stepping on the brake pedal before starting and releasing the parking brake; Figure 8 It is the state diagram of the two-type piston and the limiting slide rod when the vehicle is running.

[0027] In the diagram: 1. Caliper body; 101. Hydraulic chamber; 2. Brake pad; 3. Type I piston; 4. Brake disc; 5. Sleeve; 501. Mounting hole; 6. Type II piston; 601. Limiting groove; 7. Permanent magnet; 701. Mounting section; 702. Magnet section; 8. Electromagnet; 9. Limiting slide bar; 901. Conical surface; 902. Embedded groove; 10. Sealing tube; 1001. Sealing chamber; 1002. Oil inlet; 11. Piston ring; 12. Wedge block; 13. Elastic ring; 14. Cooling tube; 1401. Cooling fins; 15. Filter screen. Detailed Implementation

[0028] Please see Figures 1 to 8 This invention provides a brake caliper for automobiles, the technical solution of which is as follows: A type of automotive brake caliper, please refer to Figures 1 to 5 The system includes a caliper body 1 and brake pads 2. The caliper body 1 contains 2N hydraulic chambers 101, where N is a positive integer. A type I piston 3 is coaxially and slidably mounted within each of the hydraulic chambers 101. Two brake pads 2 are located on the left and right sides of the wheel brake disc 4. Multiple type I pistons 3 are symmetrically arranged on the left and right sides of the brake disc 4 and are fixedly connected to it. The hydraulic chambers 101 are arranged in pairs symmetrically, and each pair is interconnected. A sleeve 5 is threaded onto the side wall of the caliper body 1 away from the wheel. A type II piston 6 is slidably connected within the sleeve 5. A permanent magnet rod 7 is coaxially threaded onto the end of the type II piston 6 away from the brake disc 4. An electromagnet 8 is coaxially threaded onto the end of the sleeve 5 away from the brake disc 4. A heat dissipation pipe 14 is coaxially sleeved on the side wall. Multiple circumferentially distributed heat dissipation fins 1401 are provided on the outer side wall of the heat dissipation pipe 14. The permanent magnet rod 7 includes an installation section 701 and a magnet section 702. The installation section 701 and the magnet section 702 are fixedly connected, and the installation section 701 is threadedly connected to the type II piston 6. The end of the magnet section 702 away from the installation section 701 extends to the outside of the electromagnet 8. The magnet section 702 is made of neodymium magnet material. The electromagnet 8 is electrically connected to the vehicle ECU through an H-bridge circuit. The inner side of the sleeve 5 is connected to a set of symmetrically arranged hydraulic chambers 101. A filter screen 15 is provided between the sleeve 5 and the connected hydraulic chambers 101. The filter screen 15 is fixedly installed at the end of the sleeve 5 near the brake disc 4. The hydraulic chambers 101 that are not connected to the inner side of the sleeve 5 are connected to the vehicle's brake hydraulic system through hydraulic pipes.

[0029] Please see Figure 3 and Figure 4The second-type piston 6 has a frustoconical end near the brake disc 4. The pressure-bearing area of ​​the first-type piston 3 is 528 mm², and the pressure-bearing area of ​​the frustoconical end of the second-type piston 6 is 176.7 mm². Multiple mounting holes 501 are formed on the outer wall of the sleeve 5 in a circular array, penetrating both the inner and outer sides of the sleeve 5. Limiting rods 9 are slidably connected within the mounting holes 501. The two ends of the limiting rods 9 extend to the inner and outer sides of the sleeve 5, respectively. A conical surface 901 is provided on the side of the limiting rod 9 extending into the sleeve 5 and facing the electromagnet 8. The frustoconical end of the second-type piston 6 and the conical surface 901 have the same taper. A sealing tube 10 is threaded onto the outer wall of the sleeve 5. The inner wall of the sealing tube 10, the outer wall of the sleeve 5, and the side wall of the caliper body 1 form a sealing cavity 1001. A piston ring 11 is coaxially arranged within the sealing cavity 1001. The inner and outer sides of the piston ring 11 are... The piston ring 11 is slidably connected to the outer wall of the sleeve 5 and the inner wall of the sealing tube 10. An oil inlet 1002 is provided on the side wall of the sealing tube 10, penetrating both the inner and outer sides of the sealing tube 10. The oil inlet 1002 is located on the side wall of the piston ring 11 away from the brake disc 4. The oil inlet 1002 is connected to the vehicle's brake hydraulic system via a hydraulic pipe. Multiple wedge-shaped blocks 12 are provided on the side wall of the piston ring 11 near the brake disc 4, and all wedge-shaped blocks 12 face the sealing tube. The outer side of the tube 10 is inclined, and multiple limiting slide rods 9 extend to the side wall of one end of the sleeve 5 and are provided with an embedding groove 902. The wedge-shaped surface of the wedge block 12 is slidably connected to the embedding groove 902. An elastic ring 13 is coaxially provided in the sealing cavity 1001. The inner and outer walls of the elastic ring 13 are fixedly connected to the outer wall of the limiting slide rod 9 and the inner wall of the sealing tube 10, respectively. The elastic ring 13 is a hollow structure. A limiting groove 601 is coaxially provided on the conical side wall of the type II piston 6.

[0030] Working principle: Please refer to Figures 1 to 8When the parking brake is applied, the driver presses the electronic parking button, and the vehicle's ECU energizes the electromagnet 8. The energized electromagnet 8 generates a magnetic field that repels the permanent magnet 7. This magnetic field pushes the permanent magnet 7 towards the brake disc 4, which in turn pushes the type-two piston 6 towards the brake disc 4. The cone-shaped end of the type-two piston 6 gradually presses against the cone surface 901 of the limiting slide rod 9, causing the limiting slide rod 9 to move outward from the sleeve 5. Under the influence of the hydraulic pressure inside the sleeve 5, the limiting slide rod 9 moves outward from the sleeve 5. As the type-two piston 6 moves towards the brake disc, the hydraulic pressure in the hydraulic chamber 101, which is connected to the inside of the sleeve 5, increases. The type-one piston 3 in the hydraulic chamber 101, which is connected to the inside of the sleeve 5, moves towards the brake disc. The piston disc moves towards the brake disc, pushing the brake pads 2 towards the brake disc. However, the vehicle's ECU does not activate the vehicle's hydraulic brake system. There is no hydraulic pressure in the hydraulic chamber 101, which is not connected to the inside of the sleeve 5, and no hydraulic pressure in the sealing chamber 1001. The piston disc does not move towards the brake disc, and the wedge block 12 cannot push the limiting slide rod 9 outward from the sleeve 5. The limiting groove 601 follows the second-type piston 6 towards the brake disc, and after the limiting groove 601 moves into the vertical projection range of the limiting slide rod 9, the limiting slide rod 9 slides into the limiting groove 601. Thus, the limiting slide rod 9 restricts the second-type piston 6 from moving away from the brake disc, thereby maintaining the braking effect and achieving the parking brake effect. Figure 6 state.

[0031] Before starting the vehicle, the driver depresses the brake pedal, and the onboard ECU again energizes the electromagnet 8. At this time, the magnetic force generated by the electromagnet 8 is in the same direction as when the parking brake is applied, still pushing the permanent magnet 7 and the type II piston 6 towards the brake disc 4. The cone end of the type II piston 6 continuously presses against the cone surface 901 of the limiting slide rod 9. However, since the limiting slide rod 9 had already slid into the limiting groove 601 during the previous parking brake application, it will first undergo some relative sliding adjustment within the limiting groove 601 under the push of the type II piston 6. As the type II piston 6 moves further, the hydraulic pressure in the hydraulic chamber 101, which is connected to the inside of the sleeve 5, continues to rise. The type I piston 3 in the hydraulic chamber 101 pushes the brake pad 2 to fit more tightly against the brake disc 4. Simultaneously, the vehicle's ECU activates the vehicle's brake hydraulic system. Hydraulic pressure begins to build in the hydraulic chamber 101, which is not connected to the inner side of the sleeve 5, and hydraulic pressure is also generated in the sealing chamber 1001. Under the action of hydraulic pressure, the piston ring 11 moves towards the brake disc 4. The wedge-shaped block 12 on the piston ring 11 slides into the groove 902 on the limiting slide rod 9, assisting in pushing the limiting slide rod 9 out of the sleeve 5, causing the limiting slide rod 9 to gradually slide out of the limiting groove 601. Figure 7State. When the limiting slide bar 9 has completely slid out of the limiting groove 601, the type II piston 6 is no longer restricted by it. After the driver releases the brake pedal, the vehicle ECU controls the direction of the current through the electromagnet 8. The electromagnet 8 generates an attractive magnetic field force on the permanent magnet 7. The magnetic field force generated by the electromagnet 8 pushes the permanent magnet 7 to move away from the brake disc 4. At this time, the type II piston 6 follows the permanent magnet 7 to move away from the brake disc 4. The hydraulic pressure in the sleeve 5 decreases, and the type II piston 6 returns to its original position under the action of hydraulic reaction force, driving the type I piston 3 to return to its original position, causing the brake pad 2 to separate from the brake disc 4. The type II piston 6 then directly connects with the... With the piston chamber connected, the hydraulic pressure in sleeve 5 decreases faster than the hydraulic pressure in the vehicle's brake hydraulic system. The limiting groove 601 moves away from the brake disc, and after passing the vertical projection range of the limiting slide rod 9, the limiting slide rod 9 returns to its original position under the hydraulic pressure within sleeve 5. The piston ring 11 and wedge block 12 also return to their original positions under the hydraulic pressure within the sealing cavity 1001. The system returns to its initial state, releasing the brakes and preparing for the next braking action. The vehicle can then start and drive normally. During normal vehicle operation, the onboard ECU disconnects the current to the electromagnet 8, and the permanent magnet rod 7 is attracted to the electromagnet 8 under magnetic force. Figure 8 state.

[0032] During vehicle operation, when the driver presses the brake pedal, the electromagnet 8 is energized, generating a magnetic field that pushes the type II piston 6 towards the brake disc 4. The cone end of the type II piston 6 gradually presses against the cone surface 901 of the limiting slide rod 9, causing the limiting slide rod 9 to move outward from the sleeve 5. Simultaneously, the piston ring 11 moves towards the brake disc 4 under hydraulic pressure. The wedge block 12 on the piston ring 11 slides against the insertion groove 902 of the limiting slide rod 9, pushing the limiting slide rod 9 outward from the sleeve 5. As the type II piston 6 continues to move towards the brake disc 4, the hydraulic pressure in the hydraulic chamber 101, which is connected to the inside of the sleeve 5, continuously increases. The type I piston 3 in the hydraulic chamber 101 is pushed by the hydraulic pressure, which in turn pushes the brake pad 2 to tightly adhere to the brake disc 4, generating braking force to decelerate the vehicle. At the same time, the vehicle's brake hydraulic system is also working. Hydraulic pressure is also established in the hydraulic chamber 101, which is not connected to the inside of the sleeve 5. All the hydraulic chambers 101 work together to achieve vehicle braking. When the driver releases the brake pedal, the vehicle's ECU quickly changes the direction of the current to the electromagnet 8. The magnetic force generated by the electromagnet 8 becomes attractive to the permanent magnet 7, pushing the permanent magnet 7 and the type-II piston 6 away from the brake disc 4. At this time, the hydraulic pressure in the sleeve 5 begins to decrease, and the type-II piston 6 returns to its original position under the action of the magnetic force of the electromagnet 8. As the type-II piston 6 returns to its original position, the hydraulic pressure in the hydraulic chamber 101, which is connected to the inside of the sleeve 5, decreases, and the type-I piston 3 also returns to its original position. The brake pad 2 separates from the brake disc 4, the vehicle's braking is released, and normal driving continues. Moreover, because the return speed of the type II piston 6 is relatively fast, the hydraulic pressure in the sleeve 5 drops faster than the hydraulic pressure in the vehicle's brake hydraulic system. During the return process of the type II piston 6, the limiting groove 601 moves away from the brake disc. After passing the vertical projection range of the limiting slide rod 9, the limiting slide rod 9 automatically returns to its original position under the action of hydraulic pressure in the sleeve 5. The piston ring 11 and the wedge block 12 also return to their initial positions under the action of hydraulic pressure in the sealing cavity 1001. The entire braking system returns to the standby state, ready to respond to the next braking demand at any time.

[0033] The specific embodiment of the present invention has been described in detail above with reference to the accompanying drawings, but the present invention is not limited to the embodiments described above. For those skilled in the art, various changes, modifications, substitutions, and variations made to these embodiments without departing from the principles and ideas of the present invention should still fall within the protection scope of the present invention.

Claims

1. A brake caliper for an automobile, comprising a caliper body (1) and brake pads (2), wherein the caliper body (1) is provided with 2N hydraulic chambers (101), where N is a positive integer, and a type-1 piston (3) is coaxially slidably mounted in each of the hydraulic chambers (101), wherein two brake pads (2) are provided in the caliper body (1), the two brake pads (2) are located on the left and right sides of a wheel brake disc (4), and the type-1 pistons (3) are symmetrically arranged on the left and right sides of the brake disc (4), and the type-1 pistons (3) are fixedly connected to the brake disc (4), characterized in that, Multiple hydraulic chambers (101) are arranged symmetrically in pairs, and each set of hydraulic chambers (101) is connected. A sleeve (5) is threadedly connected to the side wall of the caliper body (1) away from the wheel. A type II piston (6) is slidably connected inside the sleeve (5). A permanent magnet rod (7) is coaxially threaded to the end of the type II piston (6) away from the brake disc (4). An electromagnet (8) is coaxially threaded to the end of the sleeve (5) away from the brake disc (4). The end of the permanent magnet rod (7) away from the brake disc (4) extends to the outside of the electromagnet (8). The electromagnet (8) is electrically connected to the vehicle ECU through an H-bridge circuit. The inside of the sleeve (5) is connected to a set of symmetrically arranged hydraulic chambers (101). The hydraulic chambers (101) not connected to the inside of the sleeve (5) are connected to the vehicle's brake hydraulic system through hydraulic pipes.

2. The brake caliper for an automobile according to claim 1, characterized in that, The second-type piston (6) is truncated cone-shaped at the end near the brake disc (4). Multiple mounting holes (501) are provided on the outer wall of the sleeve (5). These mounting holes (501) are arranged in a circular array and penetrate both the inner and outer sides of the sleeve (5). Limiting rods (9) are slidably connected within the mounting holes (501). The two ends of the limiting rods (9) extend to the inner and outer sides of the sleeve (5), respectively. A conical surface (901) is provided on the side of the sleeve (5) facing the electromagnet (8). The cone end of the type II piston (6) and the cone surface (901) have the same taper. A sealing tube (10) is threaded onto the outer wall of the sleeve (5). The inner wall of the sealing tube (10), the outer wall of the sleeve (5), and the side wall of the caliper body (1) form a sealing cavity (1001). A piston ring (11) is coaxially arranged in the sealing cavity (1001). The inner and outer sides of the piston ring (11) are slidably connected to the outer side wall of the sleeve (5) and the inner side wall of the sealing tube (10), respectively. An oil inlet (1002) is provided on the side wall of the sealing tube (10), and the oil inlet (1002) penetrates the inner and outer sides of the sealing tube (10). The oil inlet (1002) is located on the side wall of the piston ring (11) away from the brake disc (4). The oil inlet (1002) is connected to the vehicle's brake hydraulic system through a hydraulic pipe. The piston ring (11) has multiple wedge blocks (12) on one side wall near the brake disc (4). The multiple wedge blocks (12) are inclined towards the outside of the sealing tube (10). The multiple limiting slide rods (9) have an embedding groove (902) on the side wall of one end extending outside the sleeve (5). The wedge surface of the wedge block (12) is slidably connected to the embedding groove (902). The second type piston (6) has a limiting groove (601) coaxially opened on the cone side wall.

3. The brake caliper for an automobile according to claim 1, characterized in that, The permanent magnet rod (7) includes an installation section (701) and a magnet section (702). The installation section (701) and the magnet section (702) are fixedly connected, and the installation section (701) is threadedly connected to the type II piston (6). The end of the magnet section (702) away from the installation section (701) extends to the outside of the electromagnet (8). The magnet section (702) is made of neodymium magnet material.

4. A brake caliper for automobiles according to claim 2, characterized in that, An elastic ring (13) is coaxially arranged inside the sealing cavity (1001). The inner and outer walls of the elastic ring (13) are fixedly connected to the outer wall of the limiting slide rod (9) and the inner wall of the sealing tube (10), respectively. The elastic ring (13) has a hollow structure.

5. A brake caliper for an automobile according to claim 1, characterized in that, A heat dissipation tube (14) is coaxially sleeved on the outer wall of the electromagnet (8), and multiple circumferentially distributed heat dissipation fins (1401) are provided on the outer wall of the heat dissipation tube (14).

6. A brake caliper for an automobile according to claim 1, characterized in that, The pressure-bearing area of ​​the first-type piston (3) is S1, and the pressure-bearing area of ​​the frustum-shaped end of the second-type piston (6) is S2, where 2.5·S2≤S1≤3.5·S2.

7. A brake caliper for automobiles according to claim 2, characterized in that, A filter screen (15) is provided between the sleeve (5) and the connected hydraulic chamber (101), and the filter screen (15) is fixedly installed at one end of the sleeve (5) near the brake disc (4).

Images