Low-liquid-amount automobile brake caliper and liquid casting and forging forming method

Abstract

The invention discloses a low-liquid-volume automobile brake caliper and a liquid casting and forging forming method, and relates to the technical field of automobile brake calipers and casting and forging forming, the low-liquid-volume automobile brake caliper comprises a caliper body and a caliper body support, bolts are arranged on the left side and the right side of the caliper body and the left side and the right side of the caliper body support, and the bolts are used for fixing the caliper body and the caliper body support; an oil cylinder is arranged in the center of the top of the caliper body, a piston is arranged in the oil cylinder, a brake block is arranged in the piston, an inner friction plate and an outer friction plate are embedded into the upper end and the lower end of the caliper body support respectively, a fixing ring is welded to the center of back steel on the top of the inner friction plate, and a first reset structure is arranged in the center of the fixing ring which is fixedly connected with the piston. Reset structures II are arranged at the two ends of the inner friction plate and the outer friction plate; through the reset structure, the idle stroke of the brake pedal is reduced, the dragging torque is reduced, the response speed of the brake system is increased, and the overall efficiency and performance of the brake system are improved.

Description

Technical Field

[0001] The invention relates to the technical field of automobile brake calipers and casting and forging, and in particular to a low-liquid automobile brake caliper and a liquid casting and forging method. Background Art

[0002] In modern automotive design, the braking system is a core component for ensuring driving safety. Due to their structural characteristics, traditional brake caliper assemblies often require high hydraulic pressure to achieve effective braking and are prone to generating drag torque, which not only affects the vehicle's fuel economy but can also adversely affect the durability of the braking system and the driving experience. When the vehicle brakes, the brake fluid pressure is released, and the piston needs to return to its original position, the elastic restoring force of the sealing ring and the force of the piston spring alone cannot ensure that the piston returns completely and accurately to its original position. This results in incomplete return of the brake piston, resulting in a certain degree of contact friction between the inner and outer friction plates and the brake disc.

[0003] This residual contact friction persists during vehicle operation, increasing wear on the friction pads and brake discs, shortening their service life, and causing additional brake fluid consumption. Incomplete piston return alters the pressure balance within the brake system, requiring constant fluid replenishment to maintain proper braking performance, impacting the economy and reliability of the brake system.

[0004] When conventional casting processes are used to produce automotive brake calipers, the metal grain size formed is generally larger than 50μm due to process limitations. The coarse grain structure makes it difficult for the hardness of key parts of the brake caliper, such as the cylinder wall, to meet high-performance braking requirements. Its Rockwell hardness is generally lower than 85HRB, and it is prone to wear or deformation under long-term high-pressure braking conditions.

[0005] The traditional die-casting process relies on a single pressure parameter for filling. Due to insufficient pressure matching during the flow of molten metal, the filling of precision structures such as the internal oil circuit and piston mounting holes of the caliper body is insufficient, which easily forms defects such as air holes and shrinkage, affecting the sealing and structural strength of the brake caliper.

[0006] Existing forging technology does not achieve pressure gradient control during the forming process. The forging force exerted on the metal material in different areas is not uniform enough, resulting in differences in the internal density of the product. Some areas have loose structures due to insufficient pressure. Under the action of alternating stress generated by high-frequency braking, they are prone to become the origin of fatigue cracks, significantly affecting the fatigue life of the brake caliper. Summary of the Invention

[0007] The invention provides a low-liquid-volume automobile brake caliper and a liquid casting and forging method.

[0008] A low-fluid automobile brake caliper comprises: a caliper body, a caliper body bracket, a circular through hole 1 being provided on both sides of the caliper body, a circular through hole 2 being provided on both sides of the caliper body bracket, a bolt 1 and a bolt 2 being respectively passed through and fixedly provided between the circular through hole 1 and the circular through hole 2 on both sides, the bolt 1 and the bolt 2 being used to fix the caliper body and the caliper body bracket, an oil cylinder being provided at the center of the top of the caliper body, a piston being provided in the oil cylinder, a brake pad being provided inside the piston, an inner friction plate and an outer friction plate being respectively embedded at the upper and lower ends of the caliper body bracket, a fixing ring being welded at the center of the back steel of the top of the inner friction plate, a reset structure 1 being provided at the center of the fixing ring, the fixing ring being fixedly connected to the piston, and a reset structure 2 being provided at both ends of the inner friction plate and the outer friction plate; The reset structure 1 is composed of three oblique metal pieces extending from a triangular metal piece. The triangular metal piece is embedded in the brake pad, and the other end of the oblique metal piece is buckled on the contact annular surface between the brake pad and the piston. The reset structure 1 is used to return the piston together with the friction plate when it is assembled; The reset structure 2 is composed of metal springs. Four groups of reset structures 2 are respectively arranged at both ends of the inner friction plate and the outer friction plate. The reset structure 2 is used to allow the friction plate to return to its original position and disengage from the brake disc through the elastic force of the reset structure 2 after the piston returns when the brake is not pressed.

[0009] Preferably, the ring diameter of the contact annular surface between the brake block and the piston is set to 11.5 mm, and the ring diameter of the contact annular surface is set to 11.5 mm.

[0010] Preferably, a rectangular groove of the caliper body is provided at the connection between the bottom end of the inner wall of the cylinder and the piston, and a rectangular groove of the caliper body is provided at the connection between the bottom end of the inner wall of the cylinder and the piston. The rectangular groove in the caliper body is set to C0.42 chamfer, C0.8 chamfer and 0.3×30°, and the width of the rectangular groove is set to 4.19mm.

[0011] Preferably, a liquid inlet is provided at the top end of the caliper body, and the liquid inlet is used to input brake fluid.

[0012] Preferably, the bolts 1 and 2 pass through the circular through hole 1 and the circular through hole 2 and are provided with shock-absorbing sleeves in the middle part thereof. The shock-absorbing sleeves are used to protect the bolts while absorbing the vibration energy of the automobile brake caliper.

[0013] A liquid forging and casting method for a low-liquid-volume automobile brake caliper, the method being used to prepare the automobile brake caliper, comprising the following steps: S1. Mold preparation and pretreatment: A casting and forging mold is composed of a main mold body and a detachable combined cavity module. The shape of the combined cavity module is the same as that of an automobile brake caliper. The casting and forging mold is mounted on an intelligent CNC casting and forging hydraulic press for mold pretreatment. S2. Mold Closing and Sealing: Start the mold closing cylinder of the intelligent CNC casting and forging hydraulic press, push the movable crossbeam to drive the movable mold of the casting and forging mold downward to close the mold with the fixed mold, and set a sealing strip on the mold parting surface to prevent leakage of aluminum alloy liquid; S3. Preparation and treatment of aluminum alloy liquid: adding aluminum alloy raw materials into electromagnetic induction holding furnace for melting, and controlling the temperature of aluminum alloy liquid at 700-850℃; S4, segmented injection molding: The treated aluminum alloy liquid is poured into the injection barrel with heating and heat preservation function, and the injection cylinder of the intelligent CNC casting and forging hydraulic press is started. The first and second segmented injection molding is performed towards the cavity of the casting and forging mold; S5. Multi-stage forging: When the aluminum alloy liquid fills the entire cavity of the casting and forging die and solidifies, the forging cylinder is started to perform multi-stage forging; S6, mold cooling and mold opening: After the forging is completed, the mold cooling system is started. After the cooling is completed, the forging cylinder and the injection cylinder are started in sequence, and then the mold closing cylinder is started to separate the movable mold and the fixed mold of the casting and forging mold; S7. Ejection and subsequent processing: Start the ejection cylinder of the intelligent CNC casting and forging hydraulic press, push the ejector rod to eject the cast and forged aluminum alloy caliper, perform preliminary surface cleaning on the ejected caliper, and then perform aging treatment.

[0014] Preferably, the pretreatment of the mold in S1 includes: starting the mold preheating system to preheat the mold to uniformly increase the mold temperature to 250-350°C, and simultaneously performing ultrasonic cleaning and drying on the mold cavity to remove surface oil and impurities.

[0015] Preferably, in the first stage of filling in S4, the injection punch advances at a speed of 2-6 cm per second, and the filling pressure is controlled at 3000-8000 N. When the aluminum alloy liquid fills 60%-70% of the cavity volume, it enters the second stage of filling, the injection punch speed is increased to 7-12 cm per second, and the filling pressure is increased to 800-1500 kN until the aluminum alloy liquid fills the cavity.

[0016] Preferably, in the multi-stage forging in S5, during the first stage forging, the forging punch descends at a slower speed, the forging force is controlled at 1500-3000 kN, the forging time is 2-6 seconds, the forging stroke is controlled at 0.5-2 mm, and the aluminum alloy liquid is pre-forged to preliminarily refine the grains; then the second stage forging is performed, the forging punch accelerates the downward speed, the forging force is increased to 3000-5000 kN, the forging time is 3-8 seconds, the forging stroke is controlled at 1-3 mm, and final forging is performed.

[0017] Preferably, the preliminary surface cleaning of the ejected caliper in S7 includes: removing burrs and flash, and the aging treatment includes: controlling the aging temperature at 180-220° C. for 4-8 hours. The aging treatment is used to improve the strength and hardness of the brake caliper.

[0018] Compared with the prior art, the present invention has the following beneficial effects: The first reset mechanism consists of three inclined metal plates extending from a triangular metal plate. The triangular metal plate is embedded in the brake pad, and the other end of the inclined metal plate is buckled onto the contact ring surface between the brake pad and the piston. When the piston completes the braking action and needs to return to its original position, the first reset mechanism can work closely together and drive the inner friction plate back to its original position. Compared to traditional brake calipers, where the friction pads rely on indirect piston movement or self-elastic return, the first reset mechanism achieves synchronous return of the piston and inner friction pad, ensuring that the inner friction pads accurately and promptly disengage from the brake disc as the piston returns. This synchronized return mechanism effectively avoids continuous contact and friction with the brake disc caused by delayed or incomplete return of the friction pads, significantly improving return efficiency and accuracy, fundamentally reducing brake fluid consumption caused by residual contact between the friction pads and the brake disc, and enhancing the stability and reliability of the braking system.

[0019] The second reset mechanism is composed of metal springs, with four sets of second reset mechanisms located at each end of the inner and outer friction plates. When the vehicle is not braking, after the piston has returned to its original position due to the action of the first reset mechanism, the second reset mechanism, with its own elastic properties, further pushes the inner and outer friction plates back to their original position, completely disengaging them from the brake disc.

[0020] This dual-reset mechanism design overcomes the drawback of traditional brake calipers, which rely solely on piston return while ignoring the independent return of the friction pads. Reset mechanism II applies additional force to the friction pads after the piston returns, ensuring that the pads completely separate from the brake disc even without brake fluid pressure, relying on the elastic force of reset mechanism II. This eliminates any residual contact between the pads and disc. This not only effectively reduces energy loss during braking and minimizes wear on the friction pads and discs, but also reduces excess brake fluid consumption, improving the overall performance and service life of the braking system and providing a more reliable guarantee for safe braking.

[0021] The segmented injection molding process achieves precise filling of the mold cavity with molten metal through differentiated speed and pressure control. During the first filling stage, the injection punch is propelled at a low speed of 2-6 cm / s and a low pressure of 3000-8000 N, allowing the aluminum alloy liquid to smoothly fill 60%-70% of the mold cavity volume. This effectively reduces splashing and turbulence caused by high-speed flow, preventing air from being drawn into the cavity and forming pores. It also provides ample flow buffer time for the hollowed-out areas and bolt hole channels of the caliper body bracket, ensuring the complete formation of the basic contour. In the second filling stage, the injection speed is increased to 7-12 cm / s and the pressure is increased to 800-1500 kN. The kinetic energy of high speed and high pressure is used to overcome flow resistance at the end of the mold cavity, especially in the subtle corners of deep cavity structures such as the caliper body top cylinder, allowing the molten metal to completely fill the entire cavity. This solves the problems of end-of-mold shortage and blurred contours in traditional single-pressure filling, significantly improves the filling completeness of complex cavities, and lays a foundation for a uniform and dense structure for subsequent forging and forming.

[0022] Multi-stage forging achieves gradient optimization of metal structure through staged pressure and stroke control. In the first pre-forging stage, the forging punch descends at a relatively slow speed, maintaining a short forging stroke of 0.5-2 mm for 2-6 seconds at a forging force of 1500-3000 kN. This continuous micro-pressure action crushes the grains of the aluminum alloy in the early stages of solidification, forcing the coarse primary grains to be refined into uniform equiaxed grains, fundamentally improving the basic mechanical properties of the material. In the second final forging stage, the forging punch accelerates, increasing the forging force to 3000-5000 kN, and completing a high-force forging stroke of 1-3 mm in 3-8 seconds. The high-pressure densification effect closes tiny internal shrinkage cavities, eliminates intergranular gaps, and increases the material density from less than 95% in conventional processes to over 99%. This graded forging mechanism not only avoids the mold damage and metal streamline disorder that may be caused by single high-pressure forging, but also through the synergistic effect of "pre-forging refined grains-final forging dense structure", the Rockwell hardness of the cylinder wall and bolt connection hole of the brake caliper can be stably reached above 90HRB, and the fatigue strength is improved by 30% compared with the traditional process, which significantly enhances the reliability and service life of the brake caliper under high-frequency braking conditions. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] Figure 1 A schematic diagram showing the three-dimensional structure of a low-fluid automobile brake caliper according to an embodiment of the present disclosure is shown; Figure 2 An exploded perspective structural diagram of a low-fluid automobile brake caliper according to an embodiment of the present disclosure is shown; Figure 3 A schematic diagram showing the rear perspective structure of a low-fluid-volume automobile brake caliper according to an embodiment of the present disclosure is shown; Figure 4A partially cutaway perspective structural diagram of a low-fluid-volume automobile brake caliper according to an embodiment of the present disclosure is shown; Figure 5 A schematic diagram showing the three-dimensional structure of a caliper body bracket, inner friction plates, and outer friction plates of a low-fluid volume automobile brake caliper according to an embodiment of the present disclosure is shown; Figure 6 A schematic diagram of a partially cutaway planar structure of a piston of a low-fluid-volume automobile brake caliper according to an embodiment of the present disclosure is shown; Figure 7 Schematic diagrams showing the front and back of the optimized annular diameter of the contact annular surface between the brake pad and the piston of a low-fluid automobile brake caliper according to one embodiment of the present disclosure; Figure 8 A schematic diagram of a partial cross-sectional structure of a caliper body of a low-fluid-volume automobile brake caliper according to an embodiment of the present disclosure is shown; Figure 9 Schematic diagrams showing the front and back views of the optimized rectangular groove of a caliper body of a low-fluid-volume automobile brake caliper according to an embodiment of the present disclosure; Figure 10 A flow chart of a liquid forging method for a low-fluid-volume automobile brake caliper according to an embodiment of the present disclosure is shown.

[0024] Among them: 1. Caliper body; 101. Circular through hole 1; 102. Liquid inlet; 2. Caliper body bracket; 201. Circular through hole 2; 301. Inner friction plate; 302. Outer friction plate; 401. Bolt 1; 402. Bolt 2; 403. Shock-absorbing sleeve; 5. Piston; 502. Fixed ring; 7. Reset structure 1; 8. Reset structure 2; 9. Brake pad; 10. Rectangular groove of the caliper body. DETAILED DESCRIPTION

[0025] Various exemplary embodiments, features, and aspects of the present disclosure will be described in detail below with reference to the accompanying drawings. The same reference numerals in the accompanying drawings represent elements with the same or similar functions. Although various aspects of the embodiments are shown in the accompanying drawings, the drawings are not necessarily drawn to scale unless otherwise indicated.

[0026] The word “exemplary” is used exclusively herein to mean “serving as an example, example, or illustration.” Any embodiment described herein as “exemplary” is not necessarily to be construed as preferred or advantageous over other embodiments.

[0027] In addition, numerous specific details are provided in the following detailed description to better illustrate the present disclosure. Those skilled in the art will appreciate that the present disclosure can be practiced without certain specific details. In some instances, methods, means, components, and circuits well known to those skilled in the art are not described in detail in order to highlight the main points of the present disclosure.

[0028] See also Figures 1-9As shown, a low-fluid-volume automotive brake caliper comprises a caliper body 1 and a caliper body bracket 2, which are connected via a first bolt 401 and a second bolt 402. Specifically, the caliper body 1 has circular through-holes 101 on its left and right sides, and the caliper body bracket 2 has circular through-holes 201 on its left and right sides. The two bolts pass through their corresponding through-holes and secure the caliper. A shock-absorbing sleeve 403 is mounted in the middle of the bolts. This sleeve protects the bolts while absorbing vibration energy during braking, thereby improving the stability of the braking system.

[0029] A hydraulic cylinder is located in the center of the top of the caliper body 1, housing a piston 5. A brake pad 9 is embedded within the piston. The inner and outer friction plates 301 and 302 are embedded in the upper and lower ends of the caliper body bracket 2, respectively. A fixed ring 502 is welded to the center of the inner friction plate's backing steel. A reset mechanism 7 is located at its center. This mechanism consists of three slanted metal pieces extending from a triangular metal piece. These are embedded in the brake pad 9, and the other ends of the slanted metal pieces snap onto the contact annular surface (11.5mm in diameter) between the brake pad and the piston, ensuring that the inner friction plate is reset when the piston returns. Reset mechanisms 8 are located at both ends of the inner and outer friction plates. These four sets of metal springs push the friction plates completely off the brake disc after the piston returns, creating a dual reset mechanism.

[0030] A fluid inlet 102 is located at the top of the caliper body 1 for the introduction of brake fluid. A rectangular groove 10 is located at the bottom of the cylinder's inner wall, where it connects to the piston 5. By reducing the chamfer and width of the rectangular groove, the compression of the rectangular ring is reduced, thereby reducing the required fluid volume of the brake caliper assembly and achieving the low-fluid design goal.

[0031] In some examples, the diameter of the contact ring surface in the contact area between the piston 5 and the brake pad 9 is precisely set to 11.5 mm (refer to Figure 7 This dimension design enables the inclined metal sheet of the reset structure 7 to be more tightly fastened to the contact annular surface, ensuring that the piston and the inner friction plate 301 maintain synchronous movement during the return process, avoiding the return lag problem caused by the fit clearance, and further improving the return efficiency and accuracy.

[0032] In some examples, the chamfer angle of the rectangular groove 10 of the caliper body is reduced from the traditional C0.5 and C1.4 to 0.3×30°, and the groove width is reduced to 4.19 mm (refer to Figure 9 This parameter adjustment reduces the compression of the rectangular ring within the groove, and the volume of brake fluid in the cylinder is reduced. The measured fluid volume in the brake caliper assembly is 15% less than that of a conventional design, reducing brake fluid consumption while also improving the sealing and response speed of piston 5 during movement.

[0033] In some examples, the triangular metal sheet and the oblique metal sheet of the reset structure 1 7 are made of high-strength spring steel, and the hardness reaches HRC45-50 after heat treatment; the metal spring sheet of the reset structure 2 8 is made of memory alloy material (refer to Figure 6 The spring steel material ensures that the reset structure maintains stable elastic deformation under high-frequency braking conditions. The shape-memory alloy spring has excellent fatigue resistance and can maintain a constant elastic force even after long-term use. This ensures the reliability of the dual reset mechanism and effectively avoids friction plate return failure due to material fatigue.

[0034] Reference Figure 10 As shown, a liquid forging method for a low-fluid-volume automobile brake caliper according to this embodiment includes the following steps: S1. Mold Preparation and Pretreatment: The casting and forging mold consists of a main mold body and a removable combined cavity module. The cavity profile of the combined cavity module fully matches the geometric features of the brake caliper 1 and caliper body bracket 2. The mold is bolted to the worktable of an intelligent CNC casting and forging hydraulic press. The mold preheating system is activated, raising the mold temperature uniformly to 280°C at a rate of 5°C / min. Simultaneously, the cavity surface is cleaned with a 40kHz ultrasonic cleaning solution using an aqueous degreasing agent, followed by drying with high-pressure nitrogen.

[0035] S2. Mold Closing and Sealing: Activate the hydraulic press's mold-closing cylinder, pushing the movable crossbar downward at a speed of 0.8 m / s to close the movable and fixed molds. Install high-temperature resistant silicone sealing strips around the parting surface. This preload creates a dynamic seal, preventing aluminum alloy liquid from leaking through complex boundaries, such as the rectangular groove 10 and circular through-hole 101 in the caliper body.

[0036] S3. Preparation and treatment of aluminum alloy liquid: A356.2 aluminum alloy ingot was selected and smelted in an electromagnetic induction holding furnace to 760°C. 0.1% Sr modifier was added and degassed by passing argon through a rotary degasser for 10 minutes to reduce the hydrogen content to below 0.12 mL / 100 g.

[0037] S4. Segmented injection molding: The aluminum alloy liquid is transferred to the injection barrel. In the first stage of filling, the injection punch advances at a speed of 4 cm / s and a filling pressure of 5000 N. The aluminum liquid fills the cavity to 65% of its volume. In the second stage, the filling speed is switched to 10 cm / s and the filling pressure is increased to 1200 kN. The aluminum liquid penetrates the deep cavity of the top cylinder of the caliper body at high speed and completely fills the cavity.

[0038] S5. Multi-stage forging: The first stage forging uses a forging force of 1800kN, with the punch moving down 1.2mm at a speed of 0.5mm / s and holding pressure for 4 seconds; the second stage forging is switched to a forging force of 4000kN, with the punch speed increased to 2mm / s, the stroke 2.5mm, and holding pressure for 6 seconds, so that the density of the thick wall area of the caliper body reaches 99.3%.

[0039] S6. Mold cooling and mold opening: Start the internal circulating water cooling system of the mold. After the casting temperature drops to 200℃, retract the forging cylinder and injection cylinder in sequence, and finally open the mold closing cylinder to separate the movable and fixed molds.

[0040] S7. Ejection and subsequent processing: The ejection cylinder drives the ejector rod assembly to eject the casting, and the flash at the liquid inlet 102 is cut and removed. Then, a T6 heat treatment is performed in an aging furnace at 200°C for 6 hours to increase the hardness of the caliper body to 95HRB.

[0041] The working principle of a low-fluid automobile brake caliper in the present invention is: When the driver depresses the brake pedal, brake fluid enters the cylinder through the fluid inlet 102 at the top of the caliper body 1. This hydraulic pressure acts on the piston 5, pushing it forward. The brake pad 9 inside the piston 5 moves synchronously with the piston, driving the inner friction plate 301 to press against the brake disc via the retaining ring 502. Simultaneously, the outer friction plate 302, constrained by the caliper body bracket 2, clamps against the brake disc with the inner friction plate 301, generating a braking friction torque that decelerates the vehicle.

[0042] During this process, bolt 1 401 and bolt 2 402 pass through the circular through holes of the caliper body 1 and the caliper body bracket 2. The shock-absorbing sleeve 403 in the middle absorbs the vibration energy during braking, reduces the rigid impact between components, and improves braking smoothness.

[0043] When the brake pedal is released, the hydraulic system pressure is released, and the piston 5 begins to return due to the return of brake fluid and the elastic force of the rectangular ring. The triangular metal piece of the reset structure 7 is embedded in the brake pad 9. Three extended beveled metal pieces, with a diameter of 11.5mm, clasp the contact ring between the brake pad and the piston, forming a rigid linkage. When the piston returns, the reset structure 7 directly pulls the fixed ring 502, driving the inner friction plate 301 backward synchronously. This ensures that the inner friction plate and the piston are simultaneously disengaged from the brake disc, avoiding the hysteresis caused by the indirect piston movement in traditional structures.

[0044] After the independent return piston of reset structure 2 has returned to its original position, reset structure 2 (8) at both ends of the inner and outer friction plates 301 and 302 come into play. Four sets of metal springs, leveraging their own elastic force, apply reverse thrust to the inner and outer friction plates, respectively, pushing them completely off the brake disc surface. This design overcomes the shortcomings of a single piston return mechanism. Even with slight piston displacement deviations, the elastic force of reset structure 2 ensures complete separation of the friction plates, eliminating residual contact that could cause abnormal wear and brake fluid consumption.

[0045] The rectangular groove 10 in the caliper body, where the bottom of the inner wall of the oil cylinder connects to the piston 5, has been optimized by optimizing the chamfer angles C0.42, C0.8, 0.3×30°, and a width of 4.19mm, reducing the compression of the rectangular ring. In traditional brake calipers, excessive compression of the rectangular ring increases the volume of the oil cylinder, resulting in an increase in the amount of brake fluid filled. This design reduces the compression of the rectangular ring by 30% during initial installation by reducing the size of the groove body. The measured brake caliper assembly fluid volume is 25% lower than that of the traditional solution. At the same time, the contact annulus ring diameter is precisely set to 11.5mm to ensure that the contact area between the reset structure and the piston is minimized, further reducing the amount of fluid required for piston movement and achieving the goal of low fluid volume.

[0046] While various embodiments of the present disclosure have been described above, the foregoing description is intended to be illustrative, non-exhaustive, and not limited to the disclosed embodiments. Many modifications and variations will be apparent to those skilled in the art without departing from the scope and spirit of the described embodiments. The terminology used herein is selected to best explain the principles of the embodiments, their practical applications, or technological improvements in the marketplace, or to enable others skilled in the art to understand the embodiments disclosed herein.

Claims

1. A low-fluid automobile brake caliper, characterized in that: include: The caliper body (1) and the caliper body bracket (2) are provided with a circular through hole (101) on both sides of the caliper body (1), and a circular through hole (201) on both sides of the caliper body bracket (2). A bolt (401) and a bolt (402) are respectively fixedly provided through the middle of the circular through hole (101) and the circular through hole (201) on both sides. The bolt (401) and the bolt (402) are used to fix the caliper body (1) and the caliper body bracket (2). An oil cylinder is provided at the center of the top of the caliper body (1). A piston (5) is provided in the cylinder, a brake block (9) is provided inside the piston (5), an inner friction plate (301) and an outer friction plate (302) are respectively embedded in the upper and lower ends of the caliper body bracket (2), a fixed ring (502) is welded to the center of the back steel on the top of the inner friction plate (301), a reset structure (7) is provided in the center of the fixed ring (502), the fixed ring (502) is fixedly connected to the piston (5), and reset structures (8) are provided at both ends of the inner friction plate (301) and the outer friction plate (302); The reset structure (7) is composed of three oblique metal sheets extending from a triangular metal sheet. The triangular metal sheet is embedded in the brake block (9). The other end of the oblique metal sheet is buckled on the contact annular surface between the brake block (9) and the piston (5). The reset structure (7) is used to realize the return of the piston together with the friction plate after assembly.

2. A low-fluid automobile brake caliper according to claim 1, characterized in that: The ring diameter of the contact annular surface between the brake block (9) and the piston (5) is set to 11.5 mm, and the ring diameter of the contact annular surface is set to 11.5 mm; The reset structure 2 (8) is composed of metal springs. Four sets of reset structures 2 (8) are respectively arranged at the two ends of the inner friction plate (301) and the outer friction plate (302). The reset structure 2 (8) is used for the friction plate to return to its original position and separate from the brake disc by the elastic force of the reset structure 2 (8) after the piston returns when the brake is not applied.

3. The low-fluid-volume automobile brake caliper according to claim 1, characterized in that: A caliper body rectangular groove (10) is provided at the connection between the bottom end of the inner wall of the oil cylinder and the piston. The rectangular groove in the caliper body rectangular groove (10) is set to C0.42 chamfer, C0.8 chamfer and 0.3×30°, and the width of the rectangular groove is set to 4.19 mm. The caliper body rectangular groove (10) reduces the required amount of fluid of the brake caliper assembly by reducing the compression amount of the rectangular ring.

4. The low-fluid-volume automobile brake caliper according to claim 1, characterized in that: The top end of the caliper body (1) is provided with a liquid inlet (102), and the liquid inlet (102) is used for inputting brake fluid.

5. The low-fluid automobile brake caliper according to claim 1, characterized in that: Bolt 1 (401) and bolt 2 (402) pass through circular through hole 1 (101) and circular through hole 2 (201), and a shock-absorbing sleeve (403) is provided in the middle part thereof. The shock-absorbing sleeve (403) is used for protecting the bolts and absorbing the vibration energy of the automobile brake caliper at the same time.

6. A liquid forging method for a low-liquid automobile brake caliper, characterized in that: The method is used to prepare the automobile brake caliper according to any one of claims 1 to 5, and the method comprises the following steps: S1. Mold preparation and pretreatment: A casting and forging mold is composed of a main mold body and a detachable combined cavity module. The shape of the combined cavity module is the same as that of an automobile brake caliper. The casting and forging mold is mounted on an intelligent CNC casting and forging hydraulic press for mold pretreatment. S2. Mold Closing and Sealing: Start the mold closing cylinder of the intelligent CNC casting and forging hydraulic press, push the movable crossbeam to drive the movable mold of the casting and forging mold downward to close the mold with the fixed mold, and set a sealing strip on the mold parting surface to prevent leakage of aluminum alloy liquid; S3. Preparation and treatment of aluminum alloy liquid: adding aluminum alloy raw materials into electromagnetic induction holding furnace for melting, and controlling the temperature of aluminum alloy liquid at 700-850℃; S4, segmented injection molding: The treated aluminum alloy liquid is poured into the injection barrel with heating and heat preservation function, and the injection cylinder of the intelligent CNC casting and forging hydraulic press is started. The first and second segmented injection molding is performed towards the cavity of the casting and forging mold; S5. Multi-stage forging: When the aluminum alloy liquid fills the entire cavity of the casting and forging die and solidifies, the forging cylinder is started to perform multi-stage forging; S6, mold cooling and mold opening: After the forging is completed, the mold cooling system is started. After the cooling is completed, the forging cylinder and the injection cylinder are started in sequence, and then the mold closing cylinder is started to separate the movable mold and the fixed mold of the casting and forging mold; S7. Ejection and subsequent processing: Start the ejection cylinder of the intelligent CNC casting and forging hydraulic press, push the ejector rod to eject the cast and forged aluminum alloy caliper, perform preliminary surface cleaning on the ejected caliper, and then perform aging treatment.

7. The liquid forging method for a low-liquid-volume automobile brake caliper according to claim 6, characterized in that: The pretreatment of the mold in S1 includes: starting the mold preheating system to preheat the mold to uniformly increase the mold temperature to 250-350° C., and simultaneously performing ultrasonic cleaning and drying on the mold cavity to remove surface oil and impurities.

8. The liquid forging method for a low-liquid-volume automobile brake caliper according to claim 6, characterized in that: In the first filling stage of S4, the injection punch moves forward at a speed of 2-6 cm / s, and the filling pressure is controlled at 3000-8000 N. When the aluminum alloy liquid fills 60%-70% of the cavity volume, it enters the second filling stage, the injection punch speed is increased to 7-12 cm / s, and the filling pressure is increased to 800-1500 kN until the aluminum alloy liquid fills the cavity.

9. The liquid forging method for a low-liquid-volume automobile brake caliper according to claim 6, characterized in that: In the multi-stage forging in S5, during the first stage forging, the forging punch descends at a relatively slow speed, the forging force is controlled at 1500-3000 kN, the forging time is 2-6 seconds, and the forging stroke is controlled at 0.5-2 mm, so as to pre-forge the aluminum alloy liquid and preliminarily refine the grains; then, the second stage forging is carried out, the forging punch accelerates the downward speed, the forging force is increased to 3000-5000 kN, the forging time is 3-8 seconds, and the forging stroke is controlled at 1-3 mm, so as to perform final forging.

10. The liquid forging method for a low-liquid-volume automobile brake caliper according to claim 6, characterized in that: The preliminary surface cleaning of the ejected caliper in S7 includes removing burrs and flash, and the aging treatment includes controlling the aging temperature at 180-220° C. for 4-8 hours. The aging treatment is used to improve the strength and hardness of the brake caliper.

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