An automobile drive axle housing casting static pressure molding forming device

Abstract

The application discloses a kind of static pressure molding forming device of automobile drive axle housing casting, including fixed frame, the lower end of fixed frame is fixed with bearing plate, the upper end of fixed frame is fixed with two symmetrical static pressure cylinder, the lower end of static pressure cylinder is detachably connected with upper mould, the lower end of upper mould is provided with lower mould, lower mould is slidably connected on bearing plate, the left and right ends of lower mould are respectively provided with clamping assembly, clamping assembly is slidably connected on bearing plate, the lower end of upper mould, the upper end of lower mould is respectively provided with mould groove, the front and rear ends of lower mould are respectively fixed with two left and right symmetrical stand, the upper end of lower mould is respectively provided with sliding groove in four corners, and the four-stage positioning system of vertical guidance of stand, initial positioning of sliding groove and sliding block, centering of butt joint and butt joint groove, locking of limiting column and limiting groove can constrain the relative position of mould from front and rear, left and right, vertical multidimensional, effectively solve the problem that traditional static pressure forming mould is prone to wrong edge, transverse movement, and the problem that parting surface is not tightly fitted.

Description

Technical Field

[0001] This invention relates to the field of hydrostatic technology, specifically to a hydrostatic molding apparatus for automotive drive axle housing castings. Background Technology

[0002] The axle housing of an automobile drive axle is a core casting that bears the load of the entire vehicle and transmits power. Currently, the industry generally uses a seamless steel pipe hydrostatic bulging process to complete the axle housing forming, and the corresponding traditional hydrostatic molding equipment has been widely used. Existing conventional molding equipment mostly uses a split-type mold with an end water injection structure to achieve pipe bulging. However, in actual production, two prominent defects have been exposed: First, traditional equipment relies on a simple single-level positioning structure to achieve mold alignment between the upper and lower molds, lacking a multi-dimensional hierarchical guiding and locking structure. During mold closing, the mold is prone to shifting and moving in the front-to-back and left-to-right directions, resulting in poor fit of the parting surface. After molding, the bridge housing casting is prone to quality defects such as flash on the parting surface, asymmetrical shape and size, and insufficient cavity filling. In batch production, the workpiece size consistency is poor, and the scrap rate remains high. Second, traditional molding equipment does not have an independent cavity venting and energy storage and automatic drainage integrated structure. During pipe bulging, the air inside the cavity cannot be discharged in an orderly manner. The trapped gas is very likely to form defects such as gas numbness and dents on the outer wall of the bridge housing. Moreover, a large amount of high-pressure water remains inside the bridge housing after molding. Drainage can only be completed by manually turning the workpiece, which not only increases the labor intensity of operators and lengthens the production cycle of a single piece, but also makes it easy to bump the newly formed thin-walled bridge housing during manual drainage, further increasing the probability of product scrap. In addition, traditional equipment end seals are mostly single rigid seal structures, which are suitable for pipe materials with narrow tolerance ranges and are prone to water leakage and pressure loss under high pressure expansion conditions; the sealing effect of the mold docking air circuit is poor, and gas leakage during exhaust cannot store pressure, requiring an additional lifting cylinder to complete the lifting of the workpiece. The overall structure of the equipment is complex and the manufacturing and maintenance costs are relatively high. Summary of the Invention

[0003] To address the above problems, this invention provides a static pressure molding apparatus for automotive drive axle housing castings.

[0004] To achieve the above objectives, the present invention provides the following technical solution: a static pressure molding device for automotive drive axle housing castings, comprising a fixed frame, a receiving plate fixed at the lower end of the fixed frame, two symmetrical static pressure cylinders fixed at the upper end of the fixed frame, an upper mold detachably connected to the lower end of the static pressure cylinders, a lower mold provided at the lower end of the upper mold, the lower mold being slidably connected to the receiving plate, and clamping assemblies provided at the left and right ends of the lower mold, the clamping assemblies being slidably connected to the receiving plate; The lower end of the upper mold and the upper end of the lower mold are respectively provided with mold grooves. Two symmetrical columns are fixed at the front and rear ends of the lower mold. Slide grooves are respectively provided at the four corners of the upper end of the lower mold. Connecting parts corresponding to the slide grooves are fixed at the lower end of the upper mold. The lower mold is divided into a left mold and a right mold. The clamping assembly includes a U-shaped frame. A hydraulic cylinder is fixed on the U-shaped frame. The telescopic end of the hydraulic cylinder is fixedly connected to the fixed frame.

[0005] Preferably, two symmetrically arranged light rods are fixedly connected to the U-shaped frame, and a fixed plate is slidably connected to the light rods. A water gun head is fixedly connected to the fixed plate, and a sealing sleeve is fixedly connected to the left end of the water gun head. Two symmetrically arranged telescopic cylinders are located at the right end of the fixed plate, and the other end of the telescopic cylinders is fixedly connected to the U-shaped frame. A connecting plate is slidably connected to the U-shaped frame, and a baffle plate that is detachably connected to the lower mold is fixed to one end of the connecting plate.

[0006] Preferably, the connecting component at the bottom of the upper mold includes a limiting post, a slider is slidably connected to the limiting post, a guide rod is fixedly connected to the center of the limiting post, the lower end of the guide rod passes through the slider and is slidably connected to the slider, and a spring is provided on the outer side of the guide rod, the spring being located at the upper end of the slider.

[0007] Preferably, the slide groove corresponds one-to-one with the slider, the lower end of the slide groove is provided with a limiting groove, the limiting groove corresponds one-to-one with the limiting post, the lower end of the lower mold is provided with pulleys at the four corners, the upper end of the receiving plate is provided with two symmetrical grooves, and the lower mold slides in the grooves by means of the pulleys.

[0008] Preferably, the left end of the right mold has two symmetrical butt joints fixed thereon, and the right end of the left mold has two butt grooves that correspond one-to-one with the butt joints.

[0009] Preferably, the left mold has a first air passage inside, and the right mold has a second air passage, a chamber, and a third air passage inside. One end of the first air passage is provided with a connecting sleeve, and one end of the first air passage is connected to one end of the second air passage through the connecting sleeve. The other ends of the first and second air passages are provided with one-way valves. The first and second air passages are respectively connected to the chamber. The third air passage is connected to the upper end of the chamber. The other end of the third air passage is connected to both ends of the mold groove.

[0010] Preferably, a piston is slidably connected inside the chamber, a connecting rod is fixedly connected to the upper end of the piston, a U-shaped support plate is connected to the upper end of the connecting rod, an air bladder is fixedly connected to the outer wall of the piston, sealing rubber rings fixedly connected to the piston are respectively provided on both sides of the upper end of the air bladder, and a channel is opened inside the piston, the channel is connected to the second air passage, and a filter screen is provided at the connection between the channel and the second air passage.

[0011] Preferably, the right end of the left mold is provided with an anti-detachment groove, the right end of the left mold and the left end of the right mold are respectively provided with slots, the inner side of the slots is respectively provided with insertion grooves, the outer side of the connecting sleeve is provided with an anti-detachment platform corresponding to the anti-detachment groove, and the left and right ends of the connecting sleeve are respectively provided with insertion connectors corresponding to the slots and insertion rings corresponding to the insertion grooves.

[0012] Preferably, a sealing water ring is provided at one end of the water gun head near the lower mold, and a water channel is provided inside the water gun head and the sealing sleeve. The water channel is connected to the sealing water ring and the water gun head, and a solenoid valve is provided inside the water channel.

[0013] Compared with the prior art, the beneficial effects of the present invention are as follows: 1. This device possesses high-precision mold positioning capabilities. Through a four-level positioning system consisting of vertical guide columns, initial positioning of slides and sliders, centering of butt joints and mating grooves, and locking of limit columns and limit grooves, it can constrain the relative position of the mold from multiple dimensions including front and back, left and right, and vertical. This effectively solves the problems of misalignment, lateral movement, and poor fit of parting surfaces that are common in traditional static pressure molding molds. Combined with the split lower mold structure, it not only ensures the dimensional accuracy of the bridge housing casting and the forming quality of the parting surface, but also enables convenient lateral loading and demolding of tubular blanks, significantly improving the finished product qualification rate and dimensional consistency.

[0014] 2. This device constructs a multi-reliable sealing system. The end adopts a dual structure of external sealing sleeve and internal expansion sealing of water ring with water pressure self-tightening. The higher the internal water pressure, the stronger the sealing fit. It can adapt to a certain range of pipe inner diameter tolerances and avoid water leakage failure under high pressure conditions. The air circuit connection adopts a double plug-in sealing structure, and the piston part adopts air bladder self-tightening dynamic sealing. It comprehensively ensures the stability of water pressure and air pressure during the expansion process, solves the defects of traditional rigid sealing structure that is easy to wear and insufficient pressure holding capacity, and improves the reliability and adaptability of continuous operation of the equipment.

[0015] 3. This device integrates exhaust energy storage and automatic drainage functions. During the steel pipe bulging process, it can exhaust the air in the cavity and compress and store it in the chamber. This avoids gas stagnation in the cavity, which can cause quality problems such as gas numbness and incomplete molding on the workpiece surface. It also converts the pressure of the gas that was originally directly discharged into the lifting power. After molding and mold opening, the stored high-pressure gas can be used to automatically lift one end of the workpiece to achieve tilt drainage. There is no need to configure an additional lifting drive device or manually flip the workpiece for drainage. This realizes the organic combination of energy recovery and utilization and process automation.

[0016] 4. The device has good production adaptability and economical operation and maintenance. Both the upper and lower molds are designed to be detachable and replaceable, and can be adapted to the production of various specifications of drive axle housings by changing the cavity mold, which improves the versatility of the equipment. The entire processing procedure is smooth and controllable. The pulley guide structure greatly reduces the frictional resistance of mold movement. The protective design such as the filter screen can effectively extend the service life of sealing components. In mass production scenarios, it can effectively shorten the production cycle, reduce the intensity of manual labor and equipment maintenance costs, and has high practical value and production efficiency. Attached Figure Description

[0017] Figure 1 This is a schematic diagram of the overall structure of the present invention; Figure 2 This is a schematic diagram of the upper and lower molds of the present invention; Figure 3 This is a schematic diagram of the clamping assembly of the present invention; Figure 4 This is a schematic diagram showing the separation of the upper and lower molds of the present invention; Figure 5 This is a schematic diagram of the connector of the present invention; Figure 6 This is a schematic diagram of the lower mold separation according to the present invention; Figure 7 This is a partially enlarged schematic diagram of the present invention; Figure 8 This is a cross-sectional schematic diagram of the water gun head of the present invention.

[0018] Figure labeling: 1. Fixed frame; 2. Upper mold; 3. Lower mold; 4. Clamping assembly; 5. Mold groove; 6. Column; 7. Connecting sleeve; 8. Pulley; 11. Support plate; 12. Static pressure cylinder; 21. Limiting post; 22. Slider; 23. Guide rod; 24. Spring; 31. Slide groove; 32. Limiting groove; 33. Connecting joint; 34. Connecting groove; 35. First air passage; 36. Second air passage; 37. Chamber; 38. Third air passage; 39. U-shaped support plate; 41. U-shaped frame; 42. Water 43. Gun head; 44. Fixing plate; 45. Polished rod; 46. Telescopic cylinder; 47. Hydraulic cylinder; 48. Sealing sleeve; 49. Connecting plate; 70. Baffle plate; 71. Anti-detachment platform; 72. Insertion ring; 73. Insertion connector; 111. Groove; 311. Slot; 312. Insertion groove; 313. Anti-detachment groove; 391. Connecting rod; 392. Compression spring; 393. Piston; 394. Airbag; 395. Channel; 396. Filter screen; 471. Sealing water ring; 472. Water channel; 473. Solenoid valve. Detailed Implementation

[0019] The embodiments of the present invention will be described in further detail below with reference to the accompanying drawings and examples. The following examples are for illustrative purposes only and should not be construed as limiting the scope of the invention.

[0020] Please see Figure 1 , Figure 2 , Figure 3 , Figure 4 and Figure 5 A static pressure molding device for automotive drive axle housing castings includes a fixed frame 1, with a support plate 11 fixed to the lower end of the fixed frame 1. The two are assembled together to form a gantry-type rigid load-bearing frame, providing a stable installation benchmark and force support for the entire device. This effectively counteracts the reverse force generated by high-pressure expansion during static pressure molding, solving the problems of easy deformation and difficulty in maintaining molding accuracy in traditional split frames. Two symmetrical static pressure cylinders 12 are fixed to the upper end of the fixed frame 1, using a dual-cylinder synchronous drive arrangement. This ensures uniform force distribution during the lifting and lowering of the upper mold, effectively avoiding the defects of uneven load tilting and uneven force distribution on the mold closing surface that are prone to occur with single-cylinder drive. The lower end of the static pressure cylinder 12 is detachably connected to the upper mold 2. This method facilitates the rapid replacement of the corresponding cavity mold body according to different models of bridge housing products, significantly improving the product adaptability and mold changing efficiency of the device; the lower end of the upper mold 2 is provided with a lower mold 3, which is slidably connected to the receiving plate 11. It adopts a split lower mold structure that can be opened and closed in the horizontal direction, which facilitates the lateral placement of tubular blanks and the removal of workpieces after molding, solving the problems of cumbersome loading and unloading operations and difficult demolding of integral molds; the left and right ends of the lower mold 3 are respectively provided with clamping components 4, which are slidably connected to the receiving plate 11. The clamping components 4 arranged symmetrically on both sides can synchronously drive the lower mold 3 to complete the mold closing and opening actions, ensuring that the left and right forces are symmetrical and uniform during the mold closing process, and avoiding the mold offset and misalignment problem caused by unilateral drive.

[0021] Please see Figure 2 , Figure 3 , Figure 4 and Figure 5The upper mold 2 and the lower mold 3 are respectively provided with mold grooves 5 at their lower ends. After the molds are closed, the mold grooves 5 on both sides together form a closed forming cavity that perfectly matches the shape of the target bridge shell, providing a precise forming benchmark for the bulging deformation of the steel pipe blank, which can effectively ensure the consistency and interchangeability of the bridge shell shape dimensions during mass production. The lower mold 3 is fixed with two symmetrical columns 6 at its front and rear ends. The columns 6 extend upward and cooperate with the guide holes at the corresponding positions of the upper mold 2, providing vertical guiding constraints during the mold closing process. This can strictly limit the front-rear displacement of the upper mold 2, solving the problem of front-rear offset and cavity misalignment that easily occur when the mold is closed in traditional devices, and greatly improving the accuracy of mold closing alignment. The upper end of the lower mold 3 is provided with four corners of the sliding groove 31, and the lower end of the upper mold 2 is fixed with the sliding groove 31. The connecting piece corresponding to the slide groove 31 achieves secondary precision positioning during the mold closing process through the insertion and engagement of the slide groove 31 and the connecting piece, further eliminating mold closing position deviation and ensuring cavity docking accuracy; the lower mold 3 is divided into a left mold and a right mold, which can perform horizontal opening and closing actions along the receiving plate 11, adapting to the lateral placement of tubular blanks and the part removal process after forming, avoiding the cumbersome operation of inserting the blank from the end of the mold; the clamping assembly 4 includes a U-shaped frame 41, on which a hydraulic cylinder 46 is fixed, and the telescopic end of the hydraulic cylinder 46 is fixedly connected to the fixed frame 1. The hydraulic cylinder 46 provides a stable and continuous mold closing thrust, which can effectively offset the lateral opening force on the mold during the expansion process, ensuring that the left and right molds are always tightly fitted, and preventing defects such as flash and dimensional deviations in the workpiece caused by the mold parting surface opening during expansion.

[0022] Please see Figure 2 , Figure 3 , Figure 4 and Figure 5Two symmetrically arranged smooth rods 44 are fixedly connected to the U-shaped frame 41. A fixed plate 43 is slidably connected to the smooth rods 44. The parallel guiding structure of the two smooth rods 44 ensures that the fixed plate 43 slides smoothly in the horizontal direction, avoiding skew and swaying when the filling head moves. This solves the problem of high-pressure water leakage caused by inaccurate positioning of the traditional filling head and uneven force on the sealing surface. A water gun head 42 is fixedly connected to the fixed plate 43. The water gun head 42 serves as an injection channel for high-pressure water, which can stably deliver high-pressure water output from an external high-pressure water pump to the inside of the steel pipe blank, providing a continuous and controllable power source for static pressure expansion. A sealing sleeve 47 is fixedly connected to the left end of the water gun head 42. The sealing sleeve 47 can fit tightly against the outer wall of the end of the steel pipe blank, forming the first end sealing barrier and initially blocking the path of high-pressure water overflowing from the pipe end. Two symmetrical telescopic cylinders 45 are located at the right end of the fixed plate 43. The other end of each telescopic cylinder 45 is fixedly connected to the U-shaped frame 41. The telescopic cylinders 45 independently drive the forward and backward movement of the filling end, which can be executed in steps with the mold closing action of the lower mold 3. This ensures that the sealing end can be accurately inserted into the tube blank, and avoids structural interference caused by the synchronous movement of the filling end with the lower mold 3, thereby improving the flexibility and reliability of the device. A connecting plate 48 is slidably connected to the U-shaped frame 41. One end of the connecting plate 48 is fixed with a baffle 49 that is detachably connected to the lower mold 3. The connecting plate 48 and the baffle 49 realize the transmission connection between the clamping assembly 4 and the lower mold 3. At the same time, the sliding structure of the connecting plate 48 can keep the lower mold 3 stable when the filling end moves independently, realizing independent control of the mold closing action and the filling and sealing action without interference.

[0023] Please see Figure 2 , Figure 3 , Figure 4 and Figure 5The connecting component at the bottom of the upper mold 2 includes a limiting post 21, on which a slider 22 is slidably connected. The slider 22 can slide freely vertically along the body of the limiting post 21. A guide rod 23 is fixedly connected to the center of the limiting post 21. The lower end of the guide rod 23 passes through the slider 22 and is slidably connected to the slider 22. The guide rod 23 can provide precise linear guidance for the sliding of the slider 22, avoiding jamming and wobble during the sliding process of the slider 22, and ensuring the fit accuracy and smooth operation. A spring 24 is provided on the outside of the guide rod 23, and the spring 24 is located at the upper end of the slider 22. This elastic sliding connector specifically solves the problem that traditional rigid positioning structures cannot adapt to the step-by-step action of "initial mold closing, lower mold closing, and final mold locking": In the initial stage of mold closing, the slider 22 first extends into the slide groove 31 to complete the guiding positioning. When the upper mold 2 continues to press down, the slider 22 can retract relatively, leaving space for the left and right mold closing of the lower mold 3. At the same time, the spring 24 continuously provides downward pressure to ensure that the upper and lower molds always maintain positioning and fit during the mold closing process, and there will be no misalignment. After the lower mold 3 is fully closed, the upper mold 2 can continue to press down to make the limiting post 21 insert into the limiting groove 32 to complete the final locking, thus achieving compatibility between guiding positioning and step-by-step mold closing.

[0024] Please see Figure 3 , Figure 4 , Figure 5 and Figure 6 The slide groove 31 corresponds one-to-one with the slider 22, forming the first-level guiding and positioning structure for the mold closing process, which can quickly complete the rough alignment of the upper and lower molds in the early stage of mold closing; the lower end of the slide groove 31 is provided with a limiting groove 32, which corresponds one-to-one with the limiting post 21, forming the second-level limiting structure for mold closing and locking, which can achieve rigid constraint on the lower mold 3 in the left and right directions after the mold is closed; the two-level positioning structures work together to ensure smooth guidance in the early stage of mold closing and to restrict the left and right movement of the lower mold 3 after the mold is closed, which can effectively resist the lateral movement force of the lower mold 3 during the expansion process and prevent the left and right molds from lateral misalignment leading to workpiece scrap; the lower mold 3 is provided with pulleys 8 at the four corners of the lower end, and the upper end of the receiving plate 11 is provided with two symmetrical grooves 111, and the lower mold 3 slides in the grooves 111 through the pulleys 8. The rolling engagement between pulley 8 and groove 111 significantly reduces the frictional resistance of the lower mold 3 movement, making the mold closing and opening actions smoother and more stable. At the same time, the lateral limiting effect of groove 111 can constrain the movement trajectory of the lower mold 3, ensuring that the lower mold 3 always moves back and forth along a straight line, avoiding front and back offset during the movement, and further improving the mold closing alignment accuracy.

[0025] Please see Figure 6 , Figure 7 and Figure 8The left end of the right mold has two symmetrical butt joints 33 fixed to it, and the right end of the left mold has two mating grooves 34 corresponding to the butt joints 33. When the molds are closed, the butt joints 33 are precisely embedded in the mating grooves 34, achieving precise alignment of the left and right molds during mold closing. This eliminates height differences and misalignment between the left and right molds, ensuring complete fit of the mold parting surface. This improves the sealing of the cavity and avoids defects such as excessive flash and asymmetrical shape on the parting surface of the bridge shell casting caused by mold misalignment, effectively improving the appearance quality and dimensional accuracy of the formed workpiece. The left mold has a first air passage 35 inside, and the right mold has a second air passage 36, a chamber 37, and a third air passage 38 inside. One end of the first air passage 35 is provided with a connecting sleeve 7. The first air passage 35 is connected to one end of the second air passage 36 via the connecting sleeve 7, so that the air passages inside the left and right molds form a complete connecting channel after the mold is closed, ensuring that the gas in the cavity can be smoothly discharged; the other end of the first air passage 35 and the second air passage 36 is provided with a one-way valve. The one-way valve only allows the gas inside the cavity to flow out into the air passage, preventing the gas from flowing back into the cavity, thus avoiding the gas backflow during the molding process from affecting the surface quality of the workpiece; the first air passage 35 and the second air passage 36 are respectively connected to the cavity 37, the third air passage 38 is connected to the upper end of the cavity 37, and the other end of the third air passage 38 is connected to both ends of the mold groove 5. This air passage and pressure storage structure specifically solves the problems of poor air venting in the cavity and difficulty in draining water from the workpiece after molding in traditional static pressure molding: During the expansion process of the steel tube, the air between the cavity and the tube blank is compressed and enters the first air passage 35 and the second air passage 36 through a one-way valve, and finally flows into the chamber 37 for storage, avoiding gas stagnation in the cavity that could cause defects such as gas numbness and incomplete molding on the workpiece surface; at the same time, the gas is sealed in the chamber 37 to form high-pressure energy storage, which provides power for subsequent workpiece lifting and drainage, eliminating the need for an additional lifting drive device, simplifying the equipment structure, and realizing the integration of exhaust energy storage and automatic drainage functions.

[0026] Please see Figure 6 , Figure 7 and Figure 8A piston 393 is slidably connected inside the chamber 37. A connecting rod 391 is fixedly connected to the upper end of the piston 393. A U-shaped support plate 39 is connected to the upper end of the connecting rod 391. The arc-shaped support surface of the U-shaped support plate 39 is adapted to the shape of the end of the bridge housing, which can stably support the end of the workpiece and avoid scratching the surface of the workpiece during lifting. An air bladder 394 is fixedly connected to the outer wall of the piston 393. Sealing rubber rings are respectively provided on both sides of the upper end of the air bladder 394 and fixedly connected to the piston 393. The air bladder 394 and the sealing rubber rings together form a dynamic sealing structure between the piston 393 and the inner wall of the chamber 37. A channel 395 is opened inside the piston 393. The channel 395 communicates with the second air passage 36. A filter screen 396 is provided at the connection between the channel 395 and the second air passage 36. The advantages of this structure are as follows: During the expansion process, the high-pressure gas in the second air passage 36 can enter the air bladder 394 through the channel 395, causing the air bladder 394 to expand and tightly adhere to the inner wall of the chamber 37. The higher the air pressure, the stronger the sealing force, which completely solves the problems of easy leakage and insufficient pressure holding capacity of traditional piston seals after long-term wear. The filter screen 396 can filter dust and metal debris in the gas, preventing impurities from entering the channel 395 and the air bladder 394 and causing blockage or wear, thus extending the service life of the sealing structure. After molding is completed and the mold is opened and pressure is released, the high-pressure gas stored in the chamber 37 can push the piston 393 upward, and lift one end of the bridge housing through the U-shaped support plate 39, making the bridge housing tilted and automatically discharging the residual high-pressure water inside. There is no need for manual turning and drainage, which greatly improves production efficiency and avoids water residue affecting subsequent processing steps.

[0027] Please see Figure 7 and Figure 8 The left mold has an anti-detachment groove 313 on its right end, and slots 311 are respectively provided on the right end of the left mold and the left end of the right mold. Insertion grooves 312 are respectively provided on the inner side of the slots 311. The outer side of the connecting sleeve 7 is provided with an anti-detachment platform 71 corresponding to the anti-detachment groove 313. The left and right ends of the connecting sleeve 7 are respectively provided with a plug 73 corresponding to the slot 311 and a plug ring 72 corresponding to the plug groove 312. This double-plug sealing structure solves the problems of poor sealing and easy air leakage at the air passage connection of the split mold, as well as the easy detachment and loss of the connecting parts after mold opening: the engagement of the anti-detachment platform 71 and the anti-detachment groove 313 can keep the connecting sleeve 7 always on the left mold, and it will not fall off with the right mold when the mold is opened. There is no need for repeated manual installation and alignment, which improves the efficiency of operation and the convenience of equipment use; when the mold is closed, the plug 73 is embedded in the slot 311 to form the first radial seal, and the plug ring 72 is embedded in the plug groove 312 to form the second axial seal. The two sealing structures work together to ensure the high pressure sealing at the air passage connection, avoid gas leakage during the expansion and exhaust process, and ensure that sufficient air pressure can be accumulated in the chamber 37 for subsequent lifting and drainage.

[0028] Please see Figure 7 and Figure 8 A sealing water ring 471 is provided at one end of the water gun head 42 near the lower mold 3. A water channel 472 is provided inside the water gun head 42 and the sealing sleeve 47. The water channel 472 is connected to the sealing water ring 471 and the water gun head 42. A solenoid valve 473 is provided inside the water channel 472. This water-pressure self-tightening end sealing structure solves the problems of poor adaptability to pipe size tolerances and easy leakage under high pressure in traditional rigid seals: In the initial stage of filling, some high-pressure water enters the sealing water ring 471 through the water channel 472, causing the sealing water ring 471 to expand and tightly fit against the inner wall of the steel pipe, forming an internal expansion seal. The higher the internal water pressure, the stronger the sealing force of the sealing water ring 471, and the higher the sealing reliability. It can adapt to a certain range of pipe inner diameter tolerances, reducing the requirements for blank size accuracy. The solenoid valve 473 can control the opening and closing of the water channel 472. During the pressure holding stage, the solenoid valve 473 is closed to maintain the expansion state of the sealing water ring 471. During the pressure release stage, the solenoid valve 473 is opened to release the water pressure, causing the sealing water ring 471 to contract, making it easy for the filling end to be smoothly pulled out of the steel pipe, avoiding scratching the inner wall of the workpiece end during demolding.

[0029] When using this invention: When the device is in the initial standby position, the static pressure cylinder 12 remains in the retracted state, driving the upper mold 2 to stay in the high position; the two hydraulic cylinders 46 retract synchronously, and through the connecting plate 48 and the baffle 49, the left and right molds of the lower mold 3 are pulled to separate along the groove 111 to both sides, and are in the fully open mold state; the telescopic cylinder 45 is in the retracted position, driving the water gun head 42 and the sealing sleeve 47 to retract to the inside of the U-shaped frame 41; the solenoid valve 473 remains closed, and the sealing water ring 471 is in the contracted state; the piston 393 in the chamber 37 stays at the lower limit position under the action of the compression spring 392, and the U-shaped support plate 39 is stored inside the lower mold 3, with the top surface not exceeding the bottom surface of the mold groove 5 to avoid interfering with the placement of the blank.

[0030] The operator or loading robot places the seamless steel pipe blank along the axial direction between the left and right molds of the lower mold 3, so that the pipe blank falls into the lower half cavity of the mold groove 5. The position of the pipe blank is adjusted so that its two ends are roughly aligned with the end of the mold cavity, and the loading is completed.

[0031] The hydraulic cylinders 46 on both sides extend synchronously, pushing the U-shaped frame 41 to move towards the center along the receiving plate 11. The U-shaped frame 41 drives the left and right molds to move towards each other through the connecting plate 48 and the baffle 49. The pulley 8 at the bottom of the lower mold rolls in the groove 111, greatly reducing the frictional resistance of the movement. The groove 111 also constrains the movement trajectory of the lower mold, preventing it from shifting back and forth. When the left and right molds move to initially support the billet and the billet does not wobble significantly, the hydraulic cylinders 46 stop, completing the pre-positioning of the billet. At this time, the left and right molds are not completely fitted together, leaving room for subsequent mold closing.

[0032] Two hydrostatic cylinders 12 extend synchronously, pushing the upper mold 2 vertically downwards. During the downward movement, the columns 6 on the front and rear sides of the lower mold 3 first insert into the corresponding guide holes of the upper mold 2, forming a front-to-back guiding constraint on the upper mold and preventing it from shifting or misaligning. When the slider 22 at the bottom of the upper mold 2 aligns with and extends into the slide groove 31 at the upper end of the lower mold, the hydrostatic cylinder 12 pauses, completing the initial alignment of the upper and lower molds. At this time, the slider 22 is at the lower end of the limiting post 21 under the elastic force of the spring 24, only inserted into the upper part of the slide groove 31. The limiting post 21 has not yet entered the limiting groove 32, leaving sliding space for the lower mold to subsequently close left and right.

[0033] Hydraulic cylinder 46 continues to extend synchronously, pushing the left and right molds to move towards each other. Slider 22 slides relative to each other in the groove 31, always maintaining the positioning and fit of the upper and lower molds without dislodging. During the mold closing process, the joint 33 at the left end of the right mold is precisely embedded in the mating groove 34 at the right end of the left mold, performing secondary alignment of the left and right molds to eliminate misalignment in the front-to-back and height directions, ensuring that the parting surfaces are completely aligned. When the parting surfaces of the left and right molds are tightly fitted, hydraulic cylinder 46 maintains thrust, the lower mold is fully closed, and the billet is centered and clamped by the left and right molds, coinciding with the axis of the mold groove 5. At the same time as the mold is closed, the connecting sleeve 7 at the end of the left mold is connected to the air passage interface of the right mold: the plug 73 is embedded in the slot 311 to form the first radial seal, and the plug ring 72 is embedded in the plug groove 312 to form the second axial seal, so that the first air passage 35 and the second air passage 36 are completely connected; the anti-detachment platform 71 on the outside of the connecting sleeve is engaged in the anti-detachment groove 313 to ensure that the connecting sleeve is always fixed on the left mold when the mold is opened and will not fall off or be lost.

[0034] The static pressure cylinder 12 continues to extend downwards, pushing the upper mold 2 to press down continuously. At this time, the slider 22 is blocked by the bottom surface of the slide groove 31 and slides upwards relative to the limiting post 21, compressing the spring 24 along the guide rod 23. The guide rod 23 ensures that the slider slides smoothly without jamming. The limiting post 21 moves down synchronously with the upper mold and inserts into the limiting groove 32 at the bottom of the slide groove 31, forming a rigid lock in the left and right directions for the left and right molds. This can resist the lateral force during the expansion process and prevent the left and right molds from shifting laterally. When the lower end face of the upper mold 2 is completely fitted with the upper end face of the lower mold 3, the mold groove 5 forms a completely closed molding cavity. The static pressure cylinder 12 maintains the set pressure, completing the mold locking.

[0035] The two telescopic cylinders 45 extend synchronously, pushing the fixed plate 43 horizontally along the smooth rod 44 towards the mold. The two smooth rods 44 provide precise linear guidance for the fixed plate, ensuring that the water gun head 42 is coaxial with the tube blank and avoiding misalignment that could lead to seal failure. The fixed plate drives the water gun head 42 and the sealing sleeve 47 to move forward synchronously. The sealing sleeve 47 first covers the outer wall of the steel pipe end, forming the first external seal. When the end of the water gun head 42 extends into the steel pipe to the preset depth, the telescopic cylinders 45 stop and maintain thrust, completing the liquid filling end positioning.

[0036] The double-sealed end system activates an external high-pressure water pump, injecting high-pressure water into the steel pipe through the water nozzle 42. Simultaneously, a portion of the high-pressure water flows into the water channel 472 and into the sealing water ring 471, causing the sealing water ring 471 to expand and tightly adhere to the inner wall of the steel pipe, forming a second internal expansion seal. Once the sealing water ring is fully expanded, the solenoid valve 473 closes, maintaining the internal water pressure of the sealing water ring. This self-tightening water seal enhances the sealing effect as the internal pressure increases, adapts to pipe inner diameter tolerances, and solves the problem of easy leakage under high pressure.

[0037] As the water pressure inside the steel pipe continues to rise, the pipe wall undergoes plastic deformation and gradually adheres to the inner wall of the mold cavity 5. During the bulging process, the air between the outer wall of the steel pipe and the mold cavity is compressed and enters the first air passage 35 and the second air passage 36 through the air port at the end of the cavity. It then flows into the lower space of the chamber 37 through the one-way valve, preventing gas from stagnating in the cavity and causing defects such as gas numbness and incomplete forming on the workpiece surface.

[0038] As gas continuously flows into the cavity, the pressure in the lower part of chamber 37 gradually increases, forming high-pressure energy storage. Simultaneously, some of the high-pressure gas enters the air bladder 394 through channel 395, causing the air bladder to inflate and tightly adhere to the inner wall of chamber 37. The higher the pressure, the stronger the sealing force, solving the problem of leakage caused by long-term wear of traditional sealing rings. The filter screen 396 at the channel inlet filters dust and metal debris from the gas, preventing channel blockage and air bladder wear.

[0039] When the steel pipe is fully expanded and tightly fits the inner wall of the mold groove 5, the high-pressure water pump enters the pressure holding state. The static pressure cylinder 12 and the hydraulic cylinder 46 synchronously maintain the set pressure to eliminate material springback within the pressure holding time, ensuring that the bridge housing has stable external dimensions and is fully formed.

[0040] After the pressure holding period ends, the high-pressure water pump stops and releases pressure; at the same time, the solenoid valve 473 opens, and the high-pressure water in the sealing water ring 471 flows back through the water channel 472 to release pressure, and the sealing water ring contracts and resets; then the telescopic cylinder 45 retracts, driving the water gun head 42 and the sealing sleeve 47 to be pulled out from the end of the steel pipe and return to the initial position.

[0041] After the telescopic cylinder resets, the static pressure cylinder 12 drives the upper mold 2 to rise slightly upwards, and the limiting post 21 is pulled out from the limiting groove 32, releasing the left and right locking of the lower mold; the slider 22 slides down along the limiting post 21 to reset under the rebound action of the spring 24, and the lower end remains in the sliding groove 31, maintaining the guiding relationship between the upper and lower molds. Since the cavity side of the first air passage 35 and the second air passage 36 is equipped with a one-way valve, the high-pressure gas in the lower part of the chamber 37 cannot flow back to the cavity. The high-pressure gas pushes the piston 393 to slide upwards along the cavity, compressing the compression spring 392; the piston drives the U-shaped support plate 39 to rise upwards through the connecting rod 391, supporting one end of the bridge housing and tilting it. The high-pressure water remaining inside flows out from the lower end pipe under the action of gravity, realizing automatic drainage without the need for manual turnover of the workpiece. During the upward movement of the piston, the air in the upper part of the chamber 37 is discharged to the cavity through the third air passage 38 to avoid the formation of negative pressure that hinders the movement of the piston.

[0042] After drainage is completed, hydraulic cylinder 46 retracts synchronously, driving U-shaped frame 41 to move to both sides, pulling the left and right molds apart along groove 111. After the left and right molds separate, the first air passage 35 and the second air passage 36 disconnect, and the high-pressure gas in the lower part of chamber 37 is released outward from the disconnection point, and the pressure drops rapidly; under the combined action of the bridge housing's own weight and the rebound force of compression spring 392, piston 393 drives U-shaped support plate 39 to move downward and reset, and air is drawn into the upper part of the chamber through the third air passage 38, and piston returns to the initial lower limit position. During the separation of the left and right molds, slider 22 always slides relative to each other in the slide groove 31, maintaining the positional constraint of the upper and lower molds until the left and right molds are completely separated.

[0043] After the lower mold is fully opened, the hydrostatic cylinder 12 continues to retract, causing the upper mold 2 to rise continuously. The slider 22 completely disengages from the slide groove 31, and the column 6 is pulled out from the guide hole of the upper mold. The upper mold returns to its highest standby position. At this time, the formed bridge housing casting is placed in the lower mold cavity, and the operator or robot can directly lift the workpiece to complete the single-piece processing.

[0044] Hydraulic cylinder 46 remains in the retracted mold-open state, all drive components return to the initial standby position, and the device waits for the next loading to enter the next processing cycle.

[0045] Although embodiments of the invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the invention, the scope of which is defined by the appended claims and their equivalents.

Claims

1. A static pressure molding device for automotive drive axle housing castings, characterized in that: Includes a fixed frame (1), the lower end of which is fixed with a support plate (11), the upper end of which is fixed with two symmetrical static pressure cylinders (12), the lower end of which is detachably connected with an upper mold (2), the lower end of which is provided with a lower mold (3), the lower mold (3) is slidably connected on the support plate (11), and the left and right ends of the lower mold (3) are respectively provided with clamping components (4), the clamping components (4) are slidably connected on the support plate (11); The lower end of the upper mold (2) and the upper end of the lower mold (3) are respectively provided with mold grooves (5). The front and rear ends of the lower mold (3) are respectively fixed with two left and right symmetrical columns (6). The four corners of the upper end of the lower mold (3) are respectively provided with sliding grooves (31). The lower end of the upper mold (2) is fixed with a connecting piece corresponding to the sliding groove (31). The lower mold (3) is divided into a left mold and a right mold. The clamping assembly (4) includes a U-shaped frame (41). A hydraulic cylinder (46) is fixed on the U-shaped frame (41). The telescopic end of the hydraulic cylinder (46) is fixedly connected to the fixed frame (1).

2. The static pressure molding device for automotive drive axle housing castings according to claim 1, characterized in that: Two symmetrical light rods (44) are fixedly connected to the U-shaped frame (41). A fixed plate (43) is slidably connected to the light rods (44). A water gun head (42) is fixedly connected to the fixed plate (43). A sealing sleeve (47) is fixedly connected to the left end of the water gun head (42). Two symmetrical telescopic cylinders (45) are located at the right end of the fixed plate (43). The other end of the telescopic cylinder (45) is fixedly connected to the U-shaped frame (41). A connecting plate (48) is slidably connected to the U-shaped frame (41). A baffle (49) that is detachably connected to the lower mold (3) is fixed to one end of the connecting plate (48).

3. The static pressure molding device for automotive drive axle housing castings according to claim 1, characterized in that: The connecting piece at the bottom of the upper mold (2) includes a limiting post (21), a slider (22) is slidably connected to the limiting post (21), a guide rod (23) is fixedly connected to the center of the limiting post (21), the lower end of the guide rod (23) passes through the slider (22) and is slidably connected to the slider (22), and a spring (24) is provided on the outside of the guide rod (23), the spring (24) is located at the upper end of the slider (22).

4. The static pressure molding device for automotive drive axle housing castings according to claim 3, characterized in that: The slide groove (31) corresponds one-to-one with the slider (22). The lower end of the slide groove (31) is provided with a limiting groove (32). The limiting groove (32) corresponds one-to-one with the limiting post (21). The lower end of the lower mold (3) is provided with pulleys (8) at the four corners. The upper end of the receiving plate (11) is provided with two symmetrical grooves (111). The lower mold (3) slides in the grooves (111) through the pulleys (8).

5. The static pressure molding apparatus for automotive drive axle housing castings according to claim 1, characterized in that: The left end of the right mold has two symmetrical butt joints (33) fixed, and the right end of the left mold has two butt grooves (34) that correspond one-to-one with the butt joints (33).

6. The static pressure molding apparatus for automotive drive axle housing castings according to claim 1, characterized in that: The left mold has a first air passage (35) inside, and the right mold has a second air passage (36), a chamber (37) and a third air passage (38) inside. One end of the first air passage (35) is provided with a connecting sleeve (7). One end of the first air passage (35) is connected to one end of the second air passage (36) through the connecting sleeve (7). The other ends of the first air passage (35) and the second air passage (36) are provided with a one-way valve. The first air passage (35) and the second air passage (36) are respectively connected to the chamber (37). The third air passage (38) is connected to the upper end of the chamber (37). The other end of the third air passage (38) is connected to both ends of the mold groove (5).

7. The static pressure molding apparatus for automotive drive axle housing castings according to claim 6, characterized in that: A piston (393) is slidably connected inside the chamber (37). A connecting rod (391) is fixedly connected to the upper end of the piston (393). A U-shaped support plate (39) is connected to the upper end of the connecting rod (391). An air bladder (394) is fixedly connected to the outer wall of the piston (393). Sealing rubber rings that are fixedly connected to the piston (393) are respectively provided on both sides of the upper end of the air bladder (394). A channel (395) is opened inside the piston (393). The channel (395) communicates with the second air passage (36). A filter screen (396) is provided at the connection between the channel (395) and the second air passage (36).

8. The static pressure molding apparatus for automotive drive axle housing castings according to claim 6, characterized in that: The right end of the left mold is provided with an anti-detachment groove (313), the right end of the left mold and the left end of the right mold are respectively provided with slots (311), the inner side of the slots (311) is respectively provided with insertion slots (312), the outer side of the connecting sleeve (7) is provided with an anti-detachment platform (71) corresponding to the anti-detachment groove (313), and the left and right ends of the connecting sleeve (7) are respectively provided with a plug (73) corresponding to the slot (311) and a plug ring (72) corresponding to the insertion slot (312).

9. The static pressure molding apparatus for automotive drive axle housing castings according to claim 1, characterized in that: A sealing water ring (471) is provided at one end of the water gun head (42) near the lower mold (3). A water channel (472) is provided inside the water gun head (42) and the sealing sleeve (47). The water channel (472) is connected to the sealing water ring (471) and the water gun head (42). A solenoid valve (473) is provided inside the water channel (472).

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