A clamping structure for post-treatment of an automobile axle housing after casting forming

Abstract

This invention relates to the field of axle housing component machining fixture technology, specifically proposing a post-processing clamping structure for automotive axle housings after casting; it includes an outer positioning support, two inner support assemblies, and a pressing assembly; the outer positioning support is used for floating horizontal support of the axle housing; the two inner support assemblies are used for corresponding internal support of the two sleeve seats of the axle housing; the inner support assembly includes a base beam; a reset shaft is installed on the base beam; multiple inner support components connected to the reset shaft and used together to provide elastic support for the inner wall of the sleeve seat are assembled on the base beam; a docking cylinder is fixed at one end of the base beam; multiple circumferentially distributed locking block assemblies are installed on the docking cylinder; a push-pull docking piece that can synchronously lock and cooperate with the multiple locking block assemblies is inserted into the docking cylinder; this invention improves the machining accuracy of the half-shaft sleeve assembly holes at both ends of the axle housing by using external floating adaptive support, adopting a closed-loop cooperation method with the same reference, and also by using built-in active chip removal.

Description

Technical Field

[0001] This invention relates to the field of axle housing component processing fixtures, and specifically proposes a clamping structure for post-casting processing of automotive axle housings. Background Technology

[0002] Cast axle housing is an integral axle housing formed in one piece through casting process, with high load-bearing capacity as its core advantage. It also has advantages such as high rigidity, impact resistance, and good durability. It is mainly used in large vehicles such as heavy trucks, engineering vehicles, and heavy commercial vehicles. After the cast axle housing is cast, the blank part still needs to undergo a series of post-processing processes such as surface cleaning, heat treatment, flaw detection, precision machining, and rust prevention.

[0003] The cast axle housing body includes the axle housing in the middle and sleeve seats at both ends. The sleeve seats are used to fix and install the half-shaft sleeves. During finishing, the mating surface near the end of the sleeve seat needs to be precision bored. In current machining, a double-headed opposing boring machine is usually used to simultaneously precision bore the two sleeve seats of the axle housing. The positioning fixtures mostly use positioning through the flange holes at the axle housing, support at both ends of the sleeve seats, and lateral clamping to clamp and position the axle housing. The synchronous precision boring of the two spindles of the boring machine is relied upon to ensure the coaxiality of the half-shaft sleeve assembly holes in the two sleeve seats.

[0004] Existing positioning fixtures have a simple structure and are easy to operate, meeting the positioning accuracy requirements for most automotive cast axle housing precision machining. As an important skeleton structure of the automotive drive axle assembly, the high machining accuracy of cast axle housings can improve the stability and reliability of vehicle driving and handling, as well as improve transmission efficiency and reliability, and enhance vehicle durability. Therefore, some high-end models have higher requirements for the machining accuracy of cast axle housings, and some positioning fixtures have the following shortcomings in ensuring the machining accuracy of axle housings.

[0005] 1. There is a lack of a corresponding positioning coupling structure between the positioning structure at the bridge package location and the supporting side clamp positioning structure at both ends of the sleeve seat. Since they are relatively independent, it is impossible to use the flange structure at the bridge package that has been pre-finished as the positioning reference and to effectively constrain the coaxiality accuracy requirements of the two sleeve seats.

[0006] 2. Existing positioning fixtures are basically rigid positioning fixtures, which can cause deformation of the bridge housing due to concentrated clamping force in some areas. Precision boring is completed in a deformed state, which causes the actual accuracy of the half-shaft sleeve assembly hole to be inaccurate due to the springback of the material after machining.

[0007] 3. The boring bar has a large length-to-diameter ratio and relatively poor rigidity. It is prone to vibration during precision boring. The bridge housing is in a rigid positioning and clamping state and cannot effectively absorb and consume vibration, which can easily cause machining chatter. Ultimately, this will result in poor coaxiality and roundness of the two half-shaft sleeve assembly holes, and will also produce vibration marks on the surface of the half-shaft sleeve assembly holes, resulting in substandard surface roughness.

[0008] 4. Some high-end models also adopt a bridge housing structure design with a longer sleeve seat. The support part of the existing positioning fixture is mainly distributed at both ends of the bridge housing. The bridge housing with a longer sleeve seat is more prone to bending deformation with the middle bending downward and the ends bending upward, which further affects high-precision machining.

[0009] In addition, in the existing machining process, due to the small gap between the boring bar and the inner wall of the sleeve seat, there is a problem of poor chip removal during boring. Poor chip removal will also directly affect the machining accuracy. Usually, methods such as pausing boring and actively removing chips are used to clean up the chips, which increases the trouble of chip cleaning. Summary of the Invention

[0010] To address the aforementioned problems, this invention provides a post-casting clamping structure for automotive axle housings, which solves the problems mentioned in the background section.

[0011] To achieve the above objectives, the present invention adopts the following technical solution: a post-processing clamping structure for automotive axle housing casting, comprising an outer positioning support, two inner support assemblies, and a lowering assembly; the outer positioning support is used for floating horizontal support of the axle housing.

[0012] Two internal support assemblies are used to provide corresponding internal support for the two sleeve seats of the axle housing; the internal support assembly includes a base beam; a reset shaft is mounted on the base beam; multiple internal support components are assembled on the base beam, distributed around the central axis and used to provide elastic support for the inner wall of the sleeve seat, and the internal support components are connected to the reset shaft; a docking cylinder is fixed to one end of the base beam; multiple circumferentially distributed locking block assemblies are mounted on the docking cylinder; a push-pull docking piece is inserted into the docking cylinder, which can lock synchronously with the multiple locking block assemblies. When locked, the push-pull docking piece can push and pull the base beam into or out of the inner cavity of the sleeve seat. The pressing assembly includes a reference pressure block that presses down on the end face of the axle housing flange, and a mating pressure block is mounted on the reference pressure block. When the two base beams move in opposite directions into the two sleeve seats and are in contact with each other, when the reference pressure block is pressed against the flange end face, the mating pressure block is in horizontal pressing contact with the two base beams and is in vertical insertion positioning contact. When the mating pressure block is pressed down, it synchronously drives two reset shafts. The reset shafts indirectly drive the inner support assembly to clamp and contact the inner support of the sleeve seat. The reset shafts indirectly drive the locking block assembly to unlock the push-pull docking piece. The push-pull docking piece can be pulled out from the docking cylinder and removed from the sleeve seat.

[0013] Preferably, the base beam has a horizontally formed mating surface extending into the sleeve seat at one end, which is in horizontal pressing contact with the mating pressure block; a positioning cavity is vertically formed on the mating surface; and two driving blocks are fixed on the lower end face of the mating pressure block, which are correspondingly inserted into the positioning cavities of the two base beams.

[0014] Preferably, the reset shaft includes a mandrel slidably mounted on the base beam along the central axis, one end of the mandrel extending into the positioning cavity, and a roller is horizontally rotatably mounted on the end of the mandrel extending into the positioning cavity; a bushing is fixedly fitted on the mandrel; a reset spring is fitted on the mandrel, and the two ends of the reset spring are respectively fixed on the bushing and the base beam; two drive blocks are arranged horizontally symmetrically; the drive blocks are provided with wedge surfaces that can abut against the roller.

[0015] Preferably, the base beam is provided with multiple circumferentially distributed cantilever beams; multiple internal support assemblies are circumferentially distributed with the multiple cantilever beams; the internal support assembly includes a first connecting rod and an internal support member; the two ends of the first connecting rod are respectively hinged to the bushing and the internal support member; the internal support member is slidably installed between two adjacent cantilever beams along the radial direction of the base beam; when the mating pressure block is pressed down, the driving insertion block drives the spindle to slide through the contact roller, and the bushing drives the internal support member to clamp and contact the inner wall of the sleeve seat through the first connecting rod.

[0016] Preferably, the push-pull docking component includes a docking shaft that can be inserted into the docking cylinder; the locking block assembly includes a locking block that is radially mounted on the docking cylinder; a spring plate for resetting the locking block is connected between the locking block and the docking cylinder; and the docking shaft is provided with multiple locking holes for multiple locking blocks to be inserted into.

[0017] Preferably, a wedge block is fixed on one end of the spindle opposite to the end on which the roller is mounted; the wedge block is provided with a plurality of wedge surfaces that correspond one-to-one with the lock block; when the mating pressure block is pressed down, the drive block drives the spindle to slide by contacting the roller, and the wedge block slides by contacting the lock block through the wedge surface and moves out of the lock hole to unlock.

[0018] Preferably, a chip-expelling air disc for blowing out machining debris from the sleeve seat is fixed together between the ends of the plurality of cantilever beams; the connecting cylinder is fixedly connected to the chip-expelling air disc; and the mandrel passes through the center of the chip-expelling air disc.

[0019] Preferably, a plurality of circumferentially distributed air guns are fixedly connected to the end face of the chip removal air plate facing the sleeve seat port.

[0020] Preferably, the inner support component includes an inner support slider that is slidably installed between two adjacent cantilever beams, and the inner support slider is hinged to the first connecting rod; an elastic interlayer is embedded and fixed on the inner support slider, and an inner support block is slidably installed on the inner support slider, with the inner support block fixed to the elastic interlayer.

[0021] Preferably, the lower end face of the reference pressure block is fixed with a plurality of positioning pins corresponding to the insertion flange holes.

[0022] The above technical solution has the following advantages or beneficial effects: 1. The present invention provides a post-processing clamping structure for automotive axle housings. The pressing assembly and the two inner extension structures achieve a complete closed loop of the machining reference chain through mechanical coupling, which improves the coaxiality and overall connection between the two inner extension mechanisms. It solves the problem that the existing positioning fixtures with two-end support positioning mechanisms only play an independent support positioning role at both ends, and cannot achieve positioning and cooperation with the machining reference of the axle housing. It can effectively constrain the boring machining accuracy through the machining reference.

[0023] 2. The reference pressure block is positioned and pressed onto the axle housing, ensuring the rigid constraint of the machining reference. The two support blocks can provide adaptive floating support. The two inner extension structures are matched with the lower pressure assembly with the same reference. The two inner extension structures are clamped by internal support to enhance the overall rigidity of the two sleeve seats, effectively suppressing the structural deformation of the axle housing, which is bent downward in the middle and up at both ends. The long section of internal support along the axial direction of the sleeve seat solves the problem of accuracy distortion caused by deformation due to local clamping after machining springback. The circumferential non-rigid internal support clamping can effectively absorb and consume the vibration generated during boring, thereby suppressing chatter, improving the coaxiality and roundness of the machining at both ends, and avoiding surface chatter marks.

[0024] 3. In the inner support assembly, the unlockable design of the push-pull docking part and the inner extension structure not only realizes machining avoidance, but also facilitates the automatic movement of the inner extension structure into and out of the sleeve seat; through the same reference cooperation between the pressing assembly and the two inner extension structures, the inner support clamping and unlocking can be completed synchronously and automatically. The introduction of no electrical drive components ensures the reliability and stability of the action execution.

[0025] 4. The built-in air blowing structure can promptly remove the chips generated during machining through pulse air blowing, avoiding interference with boring due to poor chip removal, and eliminating the need to stop the tool for cleaning, thus avoiding extending the machining time.

[0026] In summary, the present invention provides a post-processing clamping structure for automotive axle housings. Through external floating adaptive support, it employs a method of pressing and positioning the middle of the axle housing, clamping and positioning the internal supports of the end sleeve seats, and closed-loop constraint with the same reference for machining. Furthermore, it improves the machining accuracy of the half-shaft sleeve assembly holes at both ends of the axle housing by incorporating an active chip removal mechanism. This ensures the coaxiality and roundness of the boring holes at both ends, making it particularly suitable for high-precision machining of axle housings for high-end vehicles and axle housings with long sleeve seats. Attached Figure Description

[0027] The invention, its features, shape, and advantages will become more apparent from the following detailed description of non-limiting embodiments with reference to the accompanying drawings. Like reference numerals denote like parts throughout the drawings, which are not intentionally drawn to scale; the focus is on illustrating the spirit of the invention.

[0028] Figure 1 This is a three-dimensional diagram of the positioning and clamping of an automotive axle housing during the post-casting and clamping process. Figure 2 yes Figure 1 A planar sectional view of the half-structure in the shown state; Figure 3 It is a three-dimensional sectional view of the assembly structure of the base beam, reset shaft, inner support assembly, docking cylinder and locking block assembly; Figure 4 It is a three-dimensional sectional view of two base beams in a coaxial docking state; Figure 5 It is a three-dimensional sectional view of the assembly relationship of the reset shaft, inner support assembly, docking cylinder and locking block assembly; Figure 6 yes Figure 5 A magnified view of a section at point A in the middle; Figure 7 It is a 3D view of the assembly of the positioning shaft and the docking shaft; Figure 8 It is a three-dimensional sectional view of the push-pull docking component in a plug-in fit with the docking cylinder and the chip discharge air plate, and in a locked fit with the locking block assembly. Figure 9 It is a three-dimensional structural diagram of the pressing block; Figure 10 This is a schematic diagram of the three-dimensional structure of the bridge shell.

[0029] In the diagram: 1. External positioning support; 11. Support block; 2. Base beam; 21. Mating surface; 211. Positioning cavity; 212. Air inlet; 22. Shaft hole; 23. Cantilever beam; 231. Notched guide groove; 232. Air passage; 24. Chip removal air disc; 241. Air gun; 25. Insert shaft; 26. Insertion hole; 3. Reset shaft; 31. Mandrel; 311. Square shaft section; 312. Round shaft section; 32. Roller; 33. Wedge block; 34. Bushing; 35. Reset spring; 4. Internal support assembly; 41. Connecting rod No. 1; 42. Internal support component; 421. 422. Inner support slider; 423. Elastic interlayer; 424. Inner support block; 425. Ball bearing; 5. Connecting cylinder; 51. Ear block; 52. Guide hole; 6. Locking block assembly; 61. Locking block; 62. Spring sheet; 7. Push-pull connecting piece; 71. Positioning shaft; 72. Connecting shaft; 721. Locking hole; 722. Alternating notch; 8. Lowering assembly; 81. Reference pressure block; 811. Positioning pin; 82. Mating pressure block; 821. Drive insertion block; 822. Air connector; 83. Guide post; 84. Compression spring; 9. Bridge housing; 91. Flange; 92. Sleeve seat. Detailed Implementation

[0030] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0031] To enable those skilled in the art to better understand the present invention, the present invention will be further described in detail below with reference to the accompanying drawings and specific embodiments.

[0032] like Figure 1 As shown, a clamping structure for post-casting processing of an automotive axle housing 9, referred to as a clamping structure, includes an outer positioning support 1, two inner support assemblies, and a lowering assembly 8. The clamping structure provided by this invention is used in conjunction with a boring machine and is mounted on the worktable of the boring machine for precision boring of the axle sleeve assembly holes within the two sleeve seats 92 of the axle housing 9. It should be noted that the boring machine used in conjunction with this structure is a double-headed opposing boring machine, which can simultaneously perform precision boring of the ports of the two sleeve seats 92. Furthermore, the clamping structure is a specialized fixture for machining and positioning axle housings 9 of a defined size, and is particularly suitable for axle housings 9 with long sleeve seats 92 in high-end vehicle models requiring high machining precision.

[0033] like Figure 1 As shown, in order to avoid the spindle of the boring machine when clamping and positioning the bridge housing 9, in this embodiment, the worktable is a horizontally movable slide table; two external positioning supports 1 are provided to provide corresponding floating support for the bottom ends of the two sleeve seats 92; the external positioning support 1 includes a base fixed to the worktable by bolts, a support block 11 is vertically slidably installed on the base, a spring is fixed between the support block 11 and the base, and the support block 11 can float elastically.

[0034] like Figure 1 , Figure 2 and Figure 10As shown, two internal support assemblies are used to provide corresponding internal support for the two sleeve seats 92 of the axle housing 9, and the two internal support assemblies are symmetrically installed on both sides of the worktable in the spindle direction of the boring machine; the pressing assembly 8 is centrally arranged between the two internal support assemblies; the pressing assembly 8 includes a mounting bracket fixed to the worktable by bolts, and a hydraulic cylinder is vertically fixed on the mounting bracket by bolts. The output end of the hydraulic cylinder is fixed with a disc-shaped reference pressure block 81 by bolts. Here, the mounting bracket and the hydraulic cylinder are not shown in the attached figure; the reference pressure block 81 is used to completely cover and press against the end face of the flange 91 of the axle housing 9, and two positioning pins 811 that can be aligned and inserted into the two flange holes are welded on the lower end face of the reference pressure block 81; it should be noted that before the two sleeve seats 92 of the axle housing 9 are precision bored, the flange 91 of the axle housing 9 has been precision machined, and the end face of the flange 91 can be used as the machining reference surface, while the flange 91 hole can be used as the machining reference hole.

[0035] like Figure 1 , Figure 2 and Figure 9 As shown, a mating block 82 is also assembled below the reference block 81; two guide posts 83 are vertically fixed to the upper end face of the mating block 82 by bolts, the guide posts 83 are vertically slidably mounted on the reference block 81, and a compression spring 84 is sleeved on the guide post 83, with the two ends of the compression spring 84 fixed to the reference block 81 and the mating block 82 respectively; two drive inserts 821 are fixed to the lower end face of the mating block 82 by screws, and the two drive inserts 821 are symmetrically arranged in the distribution direction of the two inner support assemblies.

[0036] like Figure 2 , Figure 3 and Figure 4 As shown, the inner support assembly includes a cylindrical base beam 2; the maximum radius of the base beam 2 is smaller than the inner radius of the sleeve seat 92, and the base beam 2 can extend into the sleeve seat 92; the base beam 2 has a horizontal mating surface 21 at one end extending into the sleeve seat 92, which is in horizontal pressing contact with the lower end face of the mating block 82, and the mating surface 21 is arranged facing upward; a rectangular positioning cavity 211 is vertically formed on the mating surface 21, and the positioning cavity 211 is adapted to the size of the drive insert 821; a shaft hole 22 with a rectangular cross-section is formed through the base beam 2 along the central axis, and one end of the shaft hole 22 is connected to the positioning cavity 211; four cross-shaped notched guide grooves 231 are evenly distributed around the other end of the base beam 2, and the guiding direction of the notched guide grooves 231 is the radial direction of the base beam 2. The base beam 2 is divided by the four notched guide grooves 231 to form four cantilever beams 23, two of which are vertically opposite each other, and the other two are horizontally opposite each other.

[0037] like Figure 2 , Figure 3 , Figure 4 and Figure 9As shown, in order to improve the coaxial fit between the base beams 2 of the two inner support assemblies, a plug shaft 25 is coaxially welded on the end face of one base beam 2, and a plug hole 26 for the plug shaft 25 to be inserted is coaxially opened on the end face of the other base beam 2. When the opposite end faces of the two base beams 2 are in contact, the plug shaft 25 is inserted into the plug hole 26, and the two base beams 2 maintain a coaxial fit. In addition, the positioning cavities 211 on the two base beams 2 are located directly below the two drive plug blocks 821.

[0038] like Figure 2 , Figure 3 , Figure 4 , Figure 5 , Figure 6 , Figure 8 and Figure 10 As shown, in order to facilitate active chip removal during boring, in this invention, air passages 232 extending axially along the base beam 2 are provided in the two horizontally opposite suspension beams 23. Two air inlets 212 corresponding to and communicating with the two air passages 232 are provided on the mating surface 21. A chip removal air plate 24 is fixed to the ends of the four suspension beams 23. The chip removal air plate 24 is fixed to the two vertically opposite suspension beams 23 by screws. The chip removal air plate 24 is a hollow annular disc air box structure. The chip removal air plate 24 is connected to the two air passages 232. Four air guns 241 are fixedly installed on the end of the chip removal air plate 24 facing away from the suspension beam 23. The four air guns 241 and the four suspension beams 23 are evenly distributed in a circumferential manner. The gun heads of the air guns 241 are bent laterally away from the central axis of the base beam 2, so as to blow out the machining chips in the gap between the boring bar and the half-shaft sleeve assembly hole.

[0039] like Figure 2 , Figure 4 and Figure 9 As shown, the lower end face of the drive plug 821 is also fixed with four air connectors 822 that are plugged into and cooperate with the four air inlets 212 on the two base beams 2. The four air connectors 822 are connected to the air supply compressor equipped in the processing workshop through air pipes. When the opposite end faces of the two base beams 2 are in contact, the air connectors 822 are located directly above the air inlets 212.

[0040] like Figure 2 , Figure 3 , Figure 4 , Figure 5 and Figure 6As shown, a reset shaft 3 is installed on the base beam 2; the reset shaft 3 includes a spindle 31, a bushing 34, and a reset spring 35; the spindle 31 includes a square shaft section 311 and a round shaft section 312 that are fixedly connected by welding. The square shaft section 311 is slidably fitted with the shaft hole 22 of the base beam 2. A roller 32 is horizontally rotatably mounted at the end of the square shaft section 311, and the roller 32 is located in the positioning cavity 211. For ease of installation, the roller 32 can pass through the shaft hole 22 and extend into the positioning cavity 211 together with the square shaft section 311. The lower end face of the drive insert 821 is provided with a wedge surface. When the drive insert 821... During the insertion of 21 into the corresponding positioning cavity 211, the wedge surface of the drive insert 821 can abut against the roller 32; the end of the round shaft section 312 is fixed with a wedge 33 by bolts, and the round shaft section 312 together with the wedge 33 can pass through the round hole in the center of the chip discharge plate 24; the bushing 34 is fitted on the round shaft section 312 and fixed with screws. In order to achieve circumferential positioning installation, the bushing 34 and the round shaft section 312 are keyed together; the return spring 35 is fitted on the round shaft section 312, and the two ends of the return spring 35 are fixed to the base beam 2 and the bushing 34 respectively.

[0041] like Figure 3 , Figure 5 and Figure 10 As shown, four circumferentially distributed inner support components 4 are assembled on the base beam 2; the inner support components 4 are installed one-to-one at the notch guide groove 231; the inner support component 4 includes a first connecting rod 41 and an inner support member 42 for elastic support of the inner wall of the sleeve seat 92; the inner support member 42 includes an inner support slider 421 slidably installed in the notch guide groove 231, and the two ends of the first connecting rod 41 are respectively hinged to the bushing 34 and the inner support slider 421; the inner support slider 421 is provided with an embedded cavity, which is embedded in the cavity. An elastic interlayer 422, made of rubber, is embedded in the cavity. An inner support block 423 is also slidably installed inside the cavity. The two sides of the elastic interlayer 422 are glued and fixed to the cavity and the inner support block 423, respectively. The inner support 42 and the inner support slider 421 slide in the same direction. Multiple balls 424 are movably embedded on the side of the inner support block 423 opposite to the embedded cavity. The multiple balls 424 are evenly distributed in the axial direction of the base beam 2.

[0042] During the post-casting processing of the cast bridge housing 9, the surface of the cast blank layer is cleaned and polished by methods such as sandblasting to remove molding sand, oxide scale, burrs, protrusions, flash, etc., to meet the basic roughness requirements. However, the inner wall of the sleeve seat 92 is still in a rough state after cleaning. In a single inner support assembly, four inner support members 42 jointly clamp the inner wall of the sleeve seat 92. The inner support members 42 adopt a multi-layer structure design with adaptive compressible elastic interlayer 422, and the inner support contact is achieved through multiple balls 424. First, it can adapt to the roughness of the inner wall, ensuring that the four inner support members 42 can maintain effective clamping contact with the inner wall of the sleeve seat 92. Second, the contact of the balls 424 avoids the problem of local single-point clamping caused by the top contact of burrs and protrusions on the inner wall, which could lead to the near failure of the inner support on one side.

[0043] like Figure 2 , Figure 5 , Figure 6 and Figure 8 As shown, a docking cylinder 5 is mounted on the end face of the air gun 241 mounted on the chip removal air plate 24. Four lugs 51 are evenly distributed circumferentially with the four air guns 241 on the outer wall of the docking cylinder 5. The lugs 51 are fixed to the chip removal air plate 24 by screws. A guide hole 52 is radially opened on the lug 51 along the docking cylinder 5. A locking block assembly 6 is mounted on each lug 51 of the docking cylinder 5. The locking block assembly 6 includes a locking block 61 slidably installed in the guide hole 52, with locking blocks 61 on both sides... A symmetrically mounted arc-shaped spring plate 62 is provided, with pins welded to the middle and both ends of the spring plate 62. Two extension holes are provided on the side wall of the ear block 51 to correspond to the pins at both ends of the spring plate 62. The spring plate 62 is welded and fixed to the locking block 61 by the middle pin, and the pins at both ends are slidably installed in the two extension holes. The side of the wedge block 33 is provided with four wedge surfaces that correspond to the four locking block assemblies 6. The corners of the lower end of the locking block 61 that contact the wedge surfaces are rounded.

[0044] In the inner support assembly, the reset shaft 3, inner support component 4, docking cylinder 5, and locking block component 6, which are integrated and installed on the base beam 2, together form an inner extension structure that can extend into the inner cavity of the sleeve seat 92 from the port. The half-shaft sleeve assembly hole is a small section of inner hole structure near the port of the sleeve seat 92. The total length of the inner extension structure is adapted to the bridge housing 9 to be processed. When the opposite end faces of the two base beams 2 are in contact, the two inner extension structures completely avoid the half-shaft sleeve assembly hole section, that is, they will not interfere with the precision boring of both ends.

[0045] like Figure 2 , Figure 7 and Figure 8As shown, to facilitate the automatic movement of the inner extension structure into and out of the inner cavity of the sleeve seat 92, the inner support assembly also includes a push-pull docking component 7; the push-pull docking component 7 includes a fixedly mounted base, which can be mounted on the ground or on the sliding base of the worktable, i.e., the base cannot be moved; a hydraulic cylinder is horizontally fixedly mounted on the base by bolts, and the output direction of the hydraulic cylinder is along the axis of the boring machine spindle. It should be noted that the base and the hydraulic cylinder are not shown in the figure; the push-pull docking component 7 also includes a positioning shaft 71 coaxially fixed to the output rod of the hydraulic cylinder by bolts and a docking shaft 72 coaxially welded to the end of the positioning shaft 71; a stepped end face is formed between the docking shaft 72 and the positioning shaft 71. The docking shaft 72 is a cylindrical shaft; four locking holes 721 are provided on the side wall of the docking shaft 72, which are corresponding to the four locking blocks 61 and can be inserted into the docking cylinder 5, so that the inner extension structure can be sleeved on the docking shaft 72 through the docking cylinder 5, and the docking shaft 72 is used to provide support; when the end face of the step contacts the end of the docking cylinder 5, the locking block 61 and the locking hole 721 are aligned; in order to enhance the support stability, in this embodiment, the central circular hole of the chip discharge air plate 24 is the same size as the inner hole of the docking cylinder 5, and the docking shaft 72 extends and is inserted into the central circular hole of the chip discharge air plate 24. The insertion section of the docking shaft 72 is provided with a clearance notch 722 for avoiding the wedge block 33.

[0046] The docking shaft 72 and the inner extension structure can be switched between two states: locked docking and unlocked separation. In the locked docking state, the docking shaft 72 is fully inserted into the docking cylinder 5, and the locking block 61 is stably inserted into the lock hole 721 under the elastic force of the spring plate 62. In the unlocked separation state, the locking block 61 needs to be moved out of the lock hole 721.

[0047] When clamping and positioning the bridge housing 9 using the clamping structure provided by this invention, the specific process is as follows.

[0048] With the inner extension structure and the push-pull docking piece 7 locked together, the reference pressure block 81 is moved to the position where its central axis intersects with the central axis of the base beam 2 by moving the pressing assembly 8 on the worktable. It should be noted that because the position of the push-pull docking piece 7 is fixed, the intersection position can be quickly and accurately aligned by a clearly defined worktable movement stroke; the outer support positioning moves with the worktable, which facilitates avoiding the placement of the bridge housing 9 on the boring machine spindle.

[0049] The bridge housing 9 can be lifted and placed on two support blocks 11 using a crane and lifting equipment, aligning the sleeve seat 92 with the inner support assembly. It should be noted that because the bridge housing 9 is manufactured for the same model, the weight difference between different bridge housings 9 is small. Therefore, after being placed on the two outer positioning supports 1, the height fluctuation of the support blocks 11 is negligible. Through the assembly height matching between the outer positioning supports 1 and the inner support assembly, the sleeve seat 92 port of the bridge housing 9 after placement is basically aligned with the base beam 2 in the height direction. Furthermore, the maximum radius of the inner extension structure is smaller than the inner hole radius of the sleeve seat 92, and a reasonable single-sided gap is reserved. Therefore, minor deviations in alignment do not affect the subsequent extension of the inner extension structure into the sleeve seat 92. Alternatively, a lifting base can be installed between the bottom ends of the two outer positioning supports 1 for active height alignment adjustment. Subsequently, the reference pressure block 81 can be lowered slightly to facilitate the alignment of the two flange holes 91 with the two positioning pins 811 by moving the bridge housing 9.

[0050] Next, the hydraulic cylinders in the two push-pull docking parts 7 are activated simultaneously to push the two inner extension structures closer to each other, so that the inner extension structures extend into the sleeve seat 92 until they stop when the opposite end faces of the two base beams 2 contact each other. The two base beams 2 complete the coaxial docking through the insertion fit of the insertion shaft 25 and the insertion hole 26 to enhance the connection and coaxiality between the two inner extension structures. At this time, the push-pull docking parts 7 and the inner extension structures still maintain a locked fit.

[0051] Subsequently, the reference block 81 is driven by the hydraulic cylinder to continue to descend, and the lower end face of the reference block 81 presses down to cover and adhere to the end face of the flange 91, and the two positioning pins 811 are correspondingly inserted into the holes of the two flanges 91; at the same time, the mating block 82 descends synchronously with the reference block 81, and the lower end face of the mating block 82 presses down together to adhere to the mating surface 21 of the two base beams 2, and the driving insert 821 is correspondingly inserted into the positioning cavity 211, realizing the axial locking fit of the two inner extension structures.

[0052] The air connector 822 is also simultaneously inserted into the corresponding air inlet 212, thus connecting the external air passage and the air channel 232. Airflow can enter the inner cavity of the chip removal air plate 24 along the air channel 232 and can be discharged from the four air guns 241. In this embodiment, a buffer air tank and a pulse valve are also installed in the external common air passage to perform intermittent pulse blowing. Furthermore, the boring machine used in this invention employs a built-in cooling boring bar and adopts dry boring cutting to avoid… The air blower 241 interferes with the cooling of the coolant, affecting the normal machining of the boring tool. During boring, spiral-shaped chips of equal length are easily generated. Long chips are prone to getting tangled with the boring bar or stuck in the gap between the boring bar and the inner wall of the sleeve seat 92, which not only affects the normal boring process but also makes it difficult to remove chips. Therefore, it is preferable to use a cutting head with a chip breaking groove. A chip breaking tool can also be specially installed on the boring bar as a secondary cutting head for active chip breaking, so that smaller chips can be more easily blown out.

[0053] As the drive insert 821 descends and inserts into the positioning cavity 211, the wedge surface of the drive insert 821 will abut against the roller 32, thereby pushing the roller 32 to make the spindle 31 slide closer to the sleeve seat 92 port, and the return spring 35 is in a stretched state; on the other hand, the bushing 34 moves synchronously with the spindle 31, and the bushing 34 pushes the inner support member 42 to slide away from the central axis of the base beam 2 through the first connecting rod 41, and the four inner support members 42 adaptively and elastically clamp the inner support member 92 to the sleeve seat 92. On the inner wall of 2; on the other hand, the wedge 33 also moves synchronously with the spindle 31. During the movement, the wedge surface of the wedge 33 contacts the corresponding locking block 61 and pushes the locking block 61 to be removed from the lock hole 721. The docking shaft 72 and the locking block assembly 6 achieve automatic unlocking; thus, during the process of driving the insertion block 821 and the positioning cavity 211 to complete the positioning and insertion, by driving the reset shaft 3, not only is the circumferential inner support clamping of the inner wall of the sleeve seat 92 completed, but also the automatic unlocking between the push-pull docking piece 7 and the inner extension structure is realized.

[0054] The end face of flange 91 serves as the machining reference surface, and the hole in flange 91 serves as the machining reference hole. The pressing of reference pressure block 81 with the end face of flange 91 and the insertion of positioning pin 811 into the hole in flange 91 not only achieves clamping and positioning but also completes the pickup of the machining reference. The pressing of mating pressure block 82 with mating surface 21 and the positioning insertion of drive insert block 821 into positioning cavity 211 enhance the stability and overall integrity of the coaxial mating of the two inner extension structures. This not only achieves mechanical coupling between the two inner extension structures and the lower pressure assembly 8, but also enables the coupling transmission of the machining reference from reference pressure block 81 to the two inner extension structures through mating pressure block 82. The inner extension structures then act on the bridge housing 9 again through internal support clamping, achieving a complete closed loop of the machining reference chain. This solves the problem that the existing positioning fixtures with two-end support positioning mechanisms only provide independent support and positioning at both ends and cannot achieve positioning and mating with the machining reference of the bridge housing 9. It can effectively constrain the boring machining accuracy through the machining reference.

[0055] After unlocking, the hydraulic cylinder in the push-pull docking part 7 is activated again, moving the docking shaft 72 out of the sleeve seat 92. The half-shaft sleeve assembly hole section inside the sleeve seat 92 is fully exposed, and the inner support assembly completes the machining and positioning. Subsequently, the positioning and clamping rear axle housing 9 is moved to the machining position by the worktable. The two spindles of the boring machine actively adjust their positions and complete the tool setting with the two sleeve seat 92 ports. Then, the boring bar extends into the port of the sleeve seat 92 and completes the boring machining by continuously feeding inward.

[0056] During machining, the reference pressure block 81 is positioned and pressed onto the bridge housing 9, ensuring the rigid constraint of the machining reference. The two support blocks 11 can provide adaptive floating support. The two inner extension structures and the lower pressure assembly 8 achieve the same reference fit. The two inner extension structures enhance the overall rigidity of the two sleeve seats 92 through internal support clamping, effectively suppressing the structural deformation of the bridge housing 9, which is bent downward in the middle and up at both ends. The long-segment internal support design along the axial direction of the sleeve seat 92 solves the problem of accuracy distortion caused by machining springback due to deformation caused by local clamping. The circumferential non-rigid internal support clamping can effectively absorb and consume the vibration generated during boring, thereby suppressing chatter, improving the coaxiality and roundness of the machining at both ends, and avoiding surface vibration marks. In addition, the built-in air blowing structure can discharge the machining debris in time through pulse air blowing, avoiding interference from poor chip removal during boring, and eliminating the need to stop the tool for cleaning, thus extending the machining time.

[0057] After completing the boring at both ends, the spindle retracts. While maintaining the pressure on the bridge housing 9, the worktable moves the bridge housing 9 again to the position aligned with the two push-pull docking parts 7. The two docking shafts 72 move back into the sleeve seat 92 and move until the end face of the positioning shaft 71 is close to the docking cylinder 5. The hydraulic cylinder of the pressing assembly 8 is activated to move the reference pressure block 81 upward and reset it to the initial height. The pressure block 82 moves upward synchronously, driving the insertion block 821 to move upward from the positioning cavity 211. Under the elastic force of the return spring 35, the mandrel 31 resets, and the inner support 42 automatically separates from the inner wall of the sleeve seat 92. Under the elastic force of the spring plate 62, the locking block 61 inserts into the locking hole 721, and the push-pull docking parts 7 and the inner extension structure are automatically locked together. Then, the inner extension structure can be moved out of the bridge housing 9 by pushing and pulling the docking parts 7. Finally, the boring bridge housing 9 is lifted off the machining position by a crane.

[0058] In the inner support assembly, the unlockable design of the push-pull docking part 7 and the inner extension structure not only realizes machining avoidance, but also facilitates the automatic movement of the inner extension structure into and out of the sleeve seat 92; through the same reference cooperation between the pressing assembly 8 and the two inner extension structures, the automatic inner support clamping and automatic unlocking can be realized simultaneously. The introduction of no electrical drive components ensures the reliability and stability of the action execution.

[0059] In the description of this invention, it should be understood that the terms "center," "longitudinal," "lateral," "length," "width," "thickness," "upper," "lower," "vertical," "horizontal," "top," "bottom," "inner," "outer," "clockwise," "counterclockwise," "axial," "radial," and "circumferential" indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing this invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this invention.

[0060] In the description of this invention, it should also be noted that, unless otherwise explicitly specified and limited, the terms "set," "connected," "installed," and "linked" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection of two components. Those skilled in the art will understand the specific meaning of the above terms in this invention based on the specific circumstances.

[0061] The preferred embodiments of the present invention have been described above. It should be understood that the present invention is not limited to the specific embodiments described above, and the devices and structures not described in detail should be understood as being implemented in a manner common to the art; any possible variations and modifications made by those skilled in the art without departing from the technical solution of the present invention, or equivalent embodiments with equivalent changes, do not affect the essential content of the present invention. Therefore, any simple modifications, equivalent changes, and modifications made to the above embodiments based on the technical essence of the present invention without departing from the content of the technical solution of the present invention still fall within the protection scope of the technical solution of the present invention.

Claims

1. A clamping structure for post-casting of automotive axle housings, characterized in that, include: External positioning support is used to provide floating horizontal support for the bridge shell; Two internal support assemblies are used to provide corresponding internal support for the two sleeve seats of the axle housing; The internal support assembly includes a base beam; a reset shaft is mounted on the base beam; multiple internal support components are assembled on the base beam, distributed around the central axis and used together to provide elastic support for the inner wall of the sleeve seat, and the internal support components are connected to the reset shaft; a docking cylinder is fixed at one end of the base beam; multiple circumferentially distributed locking block components are mounted on the docking cylinder; a push-pull docking piece is inserted into the docking cylinder and can be synchronously locked with the multiple locking block components. When locked, the push-pull docking piece can push and pull the base beam into or out of the inner cavity of the sleeve seat. The pressing assembly includes a reference pressure block that presses down on the end face of the axle housing flange, and a mating pressure block is mounted on the reference pressure block. When the two base beams move in opposite directions into the two sleeve seats and are in contact with each other, when the reference pressure block is pressed against the flange end face, the mating pressure block is in horizontal pressing contact with the two base beams and is in vertical insertion positioning contact. When the mating pressure block is pressed down, it synchronously drives two reset shafts. The reset shafts indirectly drive the inner support assembly to clamp and contact the inner support of the sleeve seat. The reset shafts indirectly drive the locking block assembly to unlock the push-pull docking piece. The push-pull docking piece can be pulled out from the docking cylinder and removed from the sleeve seat.

2. The clamping structure for post-casting processing of automotive axle housings according to claim 1, characterized in that: The base beam has a horizontal mating surface that is in horizontal pressing contact with the mating pressure block from one end that extends into the sleeve seat; a positioning cavity is vertically formed on the mating surface; and two drive blocks are fixed on the lower end face of the mating pressure block, which are correspondingly inserted into the positioning cavities of the two base beams.

3. The post-casting clamping structure for automotive axle housings according to claim 2, characterized in that: The reset shaft includes a mandrel that is slidably mounted on the base beam along the central axis. One end of the mandrel extends into the positioning cavity, and a roller is horizontally mounted on the end of the mandrel extending into the positioning cavity. A bushing is fixedly fitted on the mandrel. A reset spring is fitted on the mandrel, and both ends of the reset spring are fixed to the bushing and the base beam, respectively. Two drive blocks are arranged horizontally symmetrically. The drive blocks are provided with wedge surfaces that can abut against the roller.

4. The post-casting clamping structure for automotive axle housings according to claim 3, characterized in that: The base beam is provided with multiple circumferentially distributed cantilever beams; multiple internal support components are circumferentially distributed with the multiple cantilever beams; the internal support components include a first connecting rod and an internal support member; the two ends of the first connecting rod are respectively hinged to the bushing and the internal support member; the internal support member is slidably installed between two adjacent cantilever beams along the radial direction of the base beam; when the mating pressure block is pressed down, the driving insertion block drives the spindle to slide through the contact roller, and the bushing drives the internal support member to clamp and contact the internal support of the inner wall of the sleeve seat through the first connecting rod.

5. The post-casting clamping structure for automotive axle housings according to claim 3, characterized in that: The push-pull docking component includes a docking shaft that can be inserted into the docking cylinder; the locking block assembly includes a locking block that is radially mounted on the docking cylinder; a spring plate for resetting the locking block is connected between the locking block and the docking cylinder; the docking shaft is provided with multiple locking holes for multiple locking blocks to be inserted into.

6. The post-casting clamping structure for automotive axle housings according to claim 5, characterized in that: A wedge block is fixed at one end of the spindle opposite to the end on which the roller is mounted; the wedge block has multiple wedge surfaces that correspond one-to-one with the lock block; when the mating pressure block is pressed down, the drive block drives the spindle to slide by contacting the roller, and the wedge block slides by contacting the lock block through the wedge surface and moves out of the lock hole to unlock.

7. The post-casting clamping structure for automotive axle housings according to claim 4, characterized in that: A chip-expelling air disc for blowing out machining debris from the sleeve seat is fixed together at the ends of multiple cantilever beams; the connecting cylinder is fixedly connected to the chip-expelling air disc; and the mandrel passes through the center of the chip-expelling air disc.

8. The post-casting clamping structure for automotive axle housings according to claim 7, characterized in that: Multiple circumferentially distributed air guns are fixedly connected to the end face of the chip removal air plate facing the sleeve seat port.

9. The post-casting clamping structure for automotive axle housings according to claim 4, characterized in that: The inner support component includes an inner support slider that is slidably installed between two adjacent cantilever beams, and the inner support slider is hinged to the first connecting rod; an elastic interlayer is embedded and fixed on the inner support slider, and an inner support block is slidably installed on the inner support slider, with the inner support block fixed to the elastic interlayer.

10. The post-casting clamping structure for automotive axle housings according to claim 1, characterized in that: The lower end face of the reference pressure block is fixed with multiple positioning pins corresponding to the insertion flange holes.

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