A multi-angle machining tool for steering knuckle

Abstract

This application discloses a multi-angle machining fixture for steering knuckles, relating to the field of machining technology. To address the problem of workpieces being scrapped due to forced clamping caused by unstable workpiece seating, this fixture mainly includes a base plate, a central positioning mechanism, an airtightness detection mechanism, and a control system. The central positioning mechanism includes a central positioning column, grippers, and a first positioning plate. The first positioning plate has a pneumatic detection hole. When the steering knuckle is stably seated and the hole is completely blocked, the air pressure increases, triggering a seating position signal, at which point the control system allows the grippers to clamp. The fixture also includes a pusher block and a receiving groove design that converts the downward pressure potential energy of the steering knuckle into a chip-removing airflow, as well as a floating support mechanism that first floats and adheres to the bottom side and then presses down on the top side, and an outer clamping mechanism. This application achieves error-proof detection and automatic cleaning during machining, eliminates machining scrap caused by raised chips, and reduces the impact of steering knuckle deformation through flexible clamping, ensuring machining accuracy.

Description

Technical Field

[0001] This application relates to the field of modern machining, and in particular to a machine tool fixture for multi-angle machining of steering knuckles. Background Technology

[0002] The automotive steering knuckle is a core safety component in the automotive steering system, with numerous holes and complex spatial angles. When machining it on a five-axis CNC machining center, the main bearing blank hole at the center of the steering knuckle and its bottom end face are usually used as the primary positioning reference. Positioning is achieved through a central tensioning fixture, while external hydraulic cylinders provide auxiliary support and clamping.

[0003] In the prior art CN112692599B, ​​a special fixture for a five-axis machining center of automotive steering knuckles is disclosed. This typically involves setting multiple fixed support columns on the fixture body and using hydraulic control to press the steering knuckle from above via multiple telescopic fixing blocks. However, this prior art still has shortcomings in actual industrial automated production: steering knuckles are usually irregular castings with draft angles or uneven surfaces on their bottom. The existing technology uses "rigid fixed support columns," and when the upper cylinder presses down forcefully, the bottom surface is not fully supported, causing internal stress and slight bending deformation in the workpiece, leading to dimensional deviations after machining. Furthermore, traditional hydraulic fixtures are covered with oil pipes, which easily cause interference between the tool and the pipes when machining parts like steering knuckles with multiple interference characteristics. Metal chips also tend to accumulate, and if clamping is forced before proper placement due to chip interference, the entire batch of products will be scrapped. Summary of the Invention

[0004] To address the problem of machining defects caused by forced clamping due to raised iron filings or skewed workpiece placement in existing technologies, this application provides a multi-angle machining tooling for steering knuckles.

[0005] The technical solution provided in this application for a multi-angle machining tooling fixture for steering knuckles is as follows: A multi-angle machining fixture for steering knuckles includes: a base plate with an internal hydraulic system; a center positioning mechanism including a central positioning post vertically mounted on the base plate and a gripper positioned on top of the central positioning post, the central positioning post having a first positioning disc on its periphery for supporting the bottom side of the steering knuckle, the gripper being connected to the hydraulic system for controlling the gripper to clamp the steering knuckle from its center; and an airtightness testing mechanism including a detection air path connected to a pneumatic pressure detection element, the top surface of the first positioning disc having a pneumatic detection element communicating with the detection air path. A measuring hole and a control system electrically connected to the air pressure detection element and the hydraulic system are configured to: in response to receiving a seating position signal sent by the air pressure detection element, trigger the hydraulic system to drive the gripper to clamp the steering knuckle; wherein, the seating position signal corresponds to the steering knuckle seating on the first positioning plate, thereby blocking the pneumatic detection hole and causing the air pressure in the detection air circuit to rise to a preset threshold; if the pneumatic detection hole is not completely blocked and the seating position signal is not received, the control system does not output a trigger command to keep the gripper in a released state.

[0006] By adopting the above technical solution, and utilizing the electronic control linkage between the airtightness detection mechanism and the control system and hydraulic system, automatic foolproof detection of the steering knuckle's seated state is achieved. Only when the bottom surface of the steering knuckle is completely and stably attached to the first positioning plate, and all pneumatic detection holes are sealed to ensure the air pressure meets the standard, will the control system allow the clamping action to be triggered, preventing forced clamping and batch processing defects caused by iron filings being raised or the knuckle being placed crookedly.

[0007] Optionally, a receiving groove is provided circumferentially on the outer wall of the central positioning post between the gripper and the first positioning disk. A push block is slidably fitted in the receiving groove. A reset member is provided between the push block and the inner wall of the receiving groove. The reset member provides elastic potential energy to the push block to move away from the receiving groove, so that when the steering knuckle is lowered, the weight of the steering knuckle presses the push block to overcome the elastic potential energy of the reset member and move it closer to the inner wall of the receiving groove. The push block abuts against the inner sidewall of the steering knuckle's central hole for center positioning.

[0008] By adopting the above technical solution, the push block protrudes from the outer wall of the central positioning column under the elastic force of the reset component. When the steering knuckle falls, the inner wall of its central hole contacts the push block, and the steering knuckle's own weight compresses the push block inward. The push block abuts against the inner wall of the central hole to achieve flexible pre-positioning and buffer guidance, thereby improving the accuracy of placement.

[0009] Optionally, when the steering knuckle is not positioned, the bottom surface of the push block is located above the pneumatic detection hole. When the airflow in the detection air path is sprayed upward through the pneumatic detection hole, the airflow is blocked by the bottom surface of the push block and thus shot towards the top surface of the first positioning plate.

[0010] By adopting the above technical solution, when the pusher is idle, its bottom surface is suspended directly above the pneumatic detection hole, forming a physical shield to protect the pneumatic detection hole and prevent cutting fluid or iron filings from falling directly into and clogging the pneumatic detection hole; at the same time, the detection airflow continuously output by the detection air path is blocked by the bottom surface of the pusher and changes direction to shoot towards the top surface of the first positioning plate, forming a continuous airflow cleaning and chip shielding on the surface of the positioning plate.

[0011] Optionally, the bottom surface of the pusher block is provided with an outwardly expanding slope so that the airflow reflected by the outwardly expanding slope is sprayed away from the center of the pneumatic detection hole.

[0012] By adopting the above technical solution, the outward-expanding inclined surface guides the detection airflow to the outer direction away from the center of the pneumatic detection hole, increasing the coverage of the airflow on the top surface of the first positioning disk, further enhancing the active purging and chip removal effect, and effectively preventing the accumulation of fine debris on the surface of the positioning disk.

[0013] Optionally, a blowing channel is provided inside the central positioning column, and a blowing hole is provided circumferentially on the side wall of the central positioning column near the first positioning disk. One end of the blowing channel is connected to the receiving groove, and the other end is connected to the blowing hole, so that the pusher squeezes the air in the receiving groove through the blowing channel and sprays it out from the blowing hole, forming a chip removal airflow on the top surface of the first positioning disk.

[0014] By adopting the above technical solution, the piston compression effect generated when the push block is pressed into the receiving groove by the gravity of the steering knuckle is used to spray the air in the receiving groove out of the blowing hole at high speed through the blowing channel, forming a pulsed chip removal airflow on the top surface of the first positioning plate. The positioning surface can be automatically cleaned by utilizing the instantaneous potential energy of the workpiece falling, ensuring the accuracy of subsequent airtightness testing and workpiece placement.

[0015] Optionally, a floating support mechanism is also included. The floating support mechanism is mounted on the base plate and distributed around the central positioning column. The floating support mechanism is driven by the hydraulic system and is used to support the steering knuckle. The floating support mechanism is controlled to rise upward to abut against the bottom surface of the steering knuckle away from the gripper.

[0016] By adopting the above technical solution, a hydraulically driven, liftable floating support is arranged around the center positioning perimeter. This support can adapt to the uneven contours of the irregular casting bottom surface, providing a uniform and stable bottom lifting force. This avoids the local suspension problem caused by the uneven bottom surface of traditional rigid support columns, and prevents the workpiece from bending and deforming when subjected to processing forces.

[0017] Optionally, the floating support mechanism includes a first support member, a second support member, a third support member, a fourth support member, and a fifth support member; the first and second support members are used to position the bottom side of the front portion of the steering knuckle, the third support member is used to position the bottom side of the middle portion of the steering knuckle, and the fourth and fifth support members are used to position the bottom side of the rear portion of the steering knuckle; the first, second, third, fourth, and fifth support members can sequentially operate to support the bottom side of the steering knuckle.

[0018] By adopting the above technical solution, the five support components provide multi-point distributed support for the three areas of the steering knuckle: the front, middle, and rear. They move sequentially and gradually fit together, which can more evenly support the complex-shaped bottom surface of the steering knuckle. This avoids workpiece displacement or tilting that may be caused by simultaneous movements, and further improves the stability and fitting accuracy of the bottom support.

[0019] Optionally, it also includes a peripheral clamping mechanism, which is mounted on the base plate and driven by the hydraulic system. The peripheral clamping mechanism is used to press down on the steering knuckle, and the downward clamping force of the peripheral clamping mechanism and the upward supporting force of the floating support mechanism form an up-and-down clamping tendency on the steering knuckle.

[0020] By adopting the above technical solution, a downward clamping mechanism is added to the floating support. The forces from the upper and lower parts counteract each other to form a flexible vertical clamping. No bending stress is generated inside the steering knuckle, which greatly enhances the overall clamping rigidity during multi-angle cutting and effectively suppresses the vibration caused by tool cutting.

[0021] Optionally, the peripheral clamping mechanism includes a first lever clamping member, a second lever clamping member, a first steering clamping member, and a second steering clamping member. The first lever clamping member is used to clamp the top side of the head of the steering knuckle, the second lever clamping member is used to clamp the top side of the middle of the steering knuckle, and the first and second steering clamping members are used to clamp the top side of the tail of the steering knuckle. The first lever clamping member, the second lever clamping member, the first steering clamping member, and the second steering clamping member can be activated sequentially to press down on the top side of the steering knuckle. When positioning, the floating support mechanism is activated first, and the peripheral clamping mechanism is activated later.

[0022] By adopting the above technical solution, the action sequence of the floating support and the outer clamping is standardized. First, the bottom floating support adaptively lifts the bottom surface of the workpiece. After the bottom is fully attached and locked, the top clamping component presses down in sequence. This flexible clamping logic of lifting first and then pressing completely eliminates the internal stress of the workpiece caused by the hard pressure of traditional clamps, and ensures the final dimensional accuracy after the clamps are released.

[0023] Optionally, it also includes a first contour positioning component and a second contour positioning component. The first contour positioning component is mounted on the base plate and is located at the center position enclosed by the floating support mechanism and the central positioning column. The first contour positioning component abuts against the head of the steering knuckle. The second contour positioning component is located on the side of the base plate away from the central positioning column and abuts against the tail of the steering knuckle. The first and second contour positioning components are used for radial positioning of the head and tail of the steering knuckle.

[0024] By adopting the above technical solution, contour-following positioning components that conform to the outline of the steering knuckle are added at both ends, which effectively restricts the radial offset of the steering knuckle in the horizontal plane and the degree of freedom of rotation around the center. In conjunction with the center positioning mechanism, the absolute spatial position accuracy of the steering knuckle is ensured during the five-axis CNC machining process.

[0025] In summary, this application includes at least one of the following beneficial technical effects: 1. This application realizes the electronic control linkage anti-foolproof mechanism between air tightness detection and hydraulic gripper. The control system will only trigger the gripper action when the steering knuckle is completely and smoothly seated, without iron filings, and all pneumatic detection holes are blocked, thus eliminating forced clamping and batch processing scrap caused by misalignment.

[0026] 2. This application designs a push block structure with a reset component around the central positioning post. The outwardly expanding inclined surface of the bottom of the push block forms a chip-proof shield to protect the pneumatic detection hole. Furthermore, by utilizing the micro-cylinder effect generated when the workpiece presses down on the push block, the air in the receiving groove is squeezed out of the blowing hole through the blowing channel to form a pulse chip removal airflow. At the same time, the push block retracts inward to buffer and flexibly pre-align the central hole, achieving adaptive cleaning and guiding positioning without the need for an additional air source.

[0027] 3. This application constructs a step-by-step clamping sequence in which the bottom floating support first fits in and the top clamping mechanism then clamps. Multiple floating support components adapt to the irregular bottom surface of the casting and lock in sequence. With the upper clamping component pressing down in sequence, a vertical clamping is formed, which completely eliminates the bending deformation of the workpiece caused by the hard pressure of traditional rigid support and ensures the final dimensional accuracy after the clamp is released. Attached Figure Description

[0028] Figure 1 This is a structural diagram of a steering knuckle in related technologies.

[0029] Figure 2 This is a schematic diagram of the overall structure of a multi-angle machining tool for steering knuckles.

[0030] Figure 3 This is another view of the overall structure of a multi-angle machining tool for steering knuckles.

[0031] Figure 4 This is another view of the tooling structure of a multi-angle machining machine tool for steering knuckles.

[0032] Figure 5 yes Figure 4 Enlarged diagram of point A in the middle.

[0033] Figure 6 This is a side view of the overall structure of a multi-angle machining tool fixture for steering knuckles.

[0034] Figure 7 It is along Figure 6 Sectional view along the AA direction.

[0035] Figure 8 yes Figure 7 Enlarged diagram of point B in the middle.

[0036] Figure 9 yes Figure 6 Enlarged diagram of point C in the middle.

[0037] Figure 10 This is a side view of the tooling structure of a multi-angle machining machine tool for steering knuckles.

[0038] Figure 11 yes Figure 10 Enlarged diagram of point D in the middle.

[0039] Explanation of reference numerals in the attached figures: 100. Steering knuckle; 110. Steering knuckle head; 111. Steering knuckle head fixing hole; 120. Steering knuckle middle; 121. Steering knuckle center hole; 130. Steering knuckle tail; 131. Steering knuckle tail fixing hole; 10. Base plate; 20. Hydraulic system; 30. Air tightness testing mechanism; 31. Pneumatic testing hole; 32. Testing air passage; 33. Air pressure testing element; 40. Center positioning mechanism; 41. Center positioning column; 42. First positioning plate; 43. Gripper; 44. Receiving groove; 45. Push block; 451 46. ​​Outwardly expanding inclined surface; 47. Reset component; 48. Purge channel; 50. Purge hole; 51. Floating support mechanism; 52. First support component; 53. Second support component; 54. Third support component; 55. Fourth support component; 56. Fifth support component; 60. Peripheral clamping mechanism; 61. First lever clamping component; 62. Second lever clamping component; 63. First steering clamping component; 64. Second steering clamping component; 70. First contour positioning component; 71. Head positioning post; 80. Second contour positioning component; 81. Tail support post. Detailed Implementation

[0040] The following is in conjunction with the appendix Figure 1-11 This application will be described in further detail.

[0041] This application discloses a multi-angle machining tooling for steering knuckles.

[0042] Reference Figure 1 First, the workpiece processed by this tooling will be described. The steering knuckle 100 is a core safety component in the automotive steering system. It has an irregular casting shape and comprises three areas: the steering knuckle head 110, the steering knuckle middle 120, and the steering knuckle tail 130. The steering knuckle head 110 is the relatively wide end, with a steering knuckle head fixing hole 111 at its center. The steering knuckle middle 120 is the main body area, with a steering knuckle center hole 121 at its center. This center hole 121 is the main bearing blank hole and serves as the primary positioning reference for five-axis CNC machining. The steering knuckle tail 130 is the slender end, with a steering knuckle tail fixing hole 131 machined on its bottom side. Because the steering knuckle 100 is a casting, its bottom surface typically exhibits casting draft angles and unevenness, which places high demands on the tooling's positioning and clamping.

[0043] Reference Figure 2 and Figure 3A multi-angle machining tool fixture for steering knuckles includes an integral structure of a base plate 10, which is bolted to the worktable of a five-axis CNC machining center. The base plate 10 integrates an oil circuit system 20, which includes a hydraulic pump station (not shown), a hydraulic control valve group (not shown), and hydraulic oil passages (not shown) built into the base plate 10, providing power to various hydraulic actuators on the fixture. The base plate 10 is connected to an airtightness testing mechanism 30, which is connected to an external air source (not shown). The air source continuously outputs a constant-pressure test airflow into the airtightness testing mechanism 30. A center positioning mechanism 40 is located at the center of the base plate 10, and the airtightness testing mechanism 30 is mounted on the center positioning mechanism 40 and extends downwards to the base plate 10, used for error-proofing detection of the seating state of the steering knuckle 100. The tooling also includes a control system (not shown in the figure) located outside the tooling. The control system is preferably a PLC programmable logic controller. The control system is electrically connected to the hydraulic control valve group and the airtightness detection mechanism 30 of the oil circuit system 20, respectively. On the base plate 10, a floating support mechanism 50, an outer pressing mechanism 60, a first contour positioning component 70, and a second contour positioning component 80 are also provided in the outward direction from the central positioning mechanism 40 for auxiliary positioning.

[0044] Reference Figure 4 and Figure 5 Specifically, the center positioning mechanism 40 serves as the first reference for placing the steering knuckle 100, and includes a center positioning post 41 vertically fixed to the center of the base plate 10. The center positioning post 41 is a cylindrical structure, vertically mounted on the base plate 10 via a flange and bolts, with its axis perpendicular to the mounting surface of the base plate 10. The top of the center positioning post 41 is provided with tensioning grippers 43. In this embodiment, three grippers 43 are evenly spaced along the circumference of the center positioning post 41, with a 120° equidistant distribution. The inner end of each gripper 43 is connected to a hydraulic rod inside the center positioning post 41, and the hydraulic rod is connected to the hydraulic oil passage of the oil circuit system 20. When the oil circuit system 20 supplies oil to the hydraulic rod, the hydraulic rod moves axially, driving the three grippers 43 to expand radially synchronously, thereby clamping the inner wall of the steering knuckle center hole 121 from the inside out. The center positioning column 41 is fitted with a first positioning plate 42 by interference fit. The first positioning plate 42 is a ring platform structure with its top surface precision ground to support the bottom end face of the steering knuckle center hole 121 and serve as the axial positioning reference of the steering knuckle 100.

[0045] Reference Figure 4 and Figure 5To ensure that the steering knuckle 100 sits smoothly and without chip interference before machining, an airtightness testing mechanism 30 is designed. A pneumatic testing hole 31 is provided on the top surface of the first positioning disk 42. In this embodiment, three pneumatic testing holes 31 are evenly spaced along the circumferential direction of the top surface of the first positioning disk 42. The positions of the three pneumatic testing holes 31 correspond to the positions of the three grippers 43, that is, each pneumatic testing hole 31 is located within a fan-shaped area between two adjacent grippers 43. The diameter of each pneumatic testing hole 31 is preferably 1-2 mm to ensure testing sensitivity while minimizing the impact on the flatness of the positioning surface.

[0046] Reference Figure 4 , Figure 7 and Figure 8 Inside the central positioning column 41, a detection air passage 32 extends downward below each pneumatic detection hole 31. The detection air passage 32 is an air channel that penetrates the interior of the central positioning column 41, and its lower end is connected to an external air source. A pressure detection element 33 is provided in the detection air passage 32. The pressure detection element 33 is mounted on the base plate 10 and connected to the detection air passage 32. The pressure detection element 33 is preferably a precision pressure sensor with a range of 0-1 MPa and an accuracy class of 0.5.

[0047] The control system is configured with the following operating logic: an external air source continuously supplies a constant pressure of detection airflow, preferably compressed air at 0.3 MPa, to the detection air passage 32. When the steering knuckle 100 is not placed or not smoothly seated, the detection airflow freely exits upward from the three pneumatic detection holes 31, and the air pressure in the detection air passage 32 remains at a low level. When the steering knuckle 100 accurately and smoothly lands on the first positioning plate 42, the bottom surface of the steering knuckle 100 completely blocks the three pneumatic detection holes 31, and the air pressure in the detection air passage 32 rapidly increases. When the air pressure detection element 33 detects that the air pressure in the detection air passage 32 has increased to a preset threshold, preferably 0.4 MPa, the air pressure detection element 33 sends a seating signal to the control system. Only after receiving the seating signal does the control system allow the output of a trigger command to control the hydraulic control valve group of the oil circuit system 20 to switch, drive the hydraulic tie rod inside the center positioning column 41 to move, and cause the three grippers 43 to synchronously expand radially to clamp the center hole 121 of the steering knuckle.

[0048] Conversely, if there are iron filings on the top surface of the first positioning plate 42 or the steering knuckle 100 is misaligned, causing one or more of the three pneumatic detection holes 31 to be incompletely blocked, the detection airflow can still leak out from the unblocked pneumatic detection holes 31. The air pressure in the detection air circuit 32 cannot rise to the preset threshold, and the air pressure detection element 33 will not send a positioning signal. At this time, the control system does not output a trigger command, the hydraulic system 20 does not operate, the three grippers 43 remain in the released state, and the control system can simultaneously issue a warning to the operator via an alarm light or display screen, indicating that the workpiece needs to be repositioned or the positioning surface cleaned. Through this electronically controlled linkage design, processing defects caused by forced clamping due to improper placement are eliminated at the source.

[0049] Reference Figure 7 and Figure 8 Specifically, a receiving groove 44 is provided circumferentially on the outer wall of the central positioning post 41 between the gripper 43 and the first positioning disk 42. In this embodiment, three receiving grooves 44 are also provided corresponding to the positions of the three grippers 43. Each receiving groove 44 extends radially along the central positioning post 41 and has a rectangular cross-section groove structure. A push block 45 is slidably fitted inside each receiving groove 44. The push block 45 is a cuboid stainless steel block, and its side facing the outer side of the central positioning post 41 is preferably designed as an inclined guide surface that is smaller at the top and larger at the bottom. A reset member 46 is provided between the push block 45 and the inner wall of the receiving groove 44. The reset member 46 is preferably a stainless steel compression spring and can provide elastic potential energy to the push block 45 away from the inner wall of the receiving groove 44.

[0050] When the steering knuckle 100 is placed downwards, the inner wall of the steering knuckle center hole 121 first contacts the inclined guide surface of the outer surface of the three push blocks 45. Since the inclined guide surface has a sloping shape that is smaller at the top and larger at the bottom, the steering knuckle 100 uses its own weight to slide down the inclined guide surface while simultaneously pressing the push blocks 45 radially inwards. The push blocks 45 overcome the elastic force of the reset member 46 and retract into the receiving groove 44. During this process, the three push blocks 45 simultaneously abut against the inner wall of the steering knuckle center hole 121 from three directions, providing a flexible initial center alignment for the steering knuckle 100, making the axis of the steering knuckle center hole 121 basically aligned with the axis of the center positioning post 41, providing guidance and buffering for the subsequent precise clamping of the gripper 43.

[0051] Reference Figure 6 , Figure 8 and Figure 9When the steering knuckle 100 is not positioned, that is, when the push block 45 extends outward to its maximum stroke position under the elastic force of the reset member 46, the bottom surface of the push block 45 is directly above the pneumatic detection hole 31. At this time, the bottom surface of the push block 45 covers and blocks the pneumatic detection hole 31 in the vertical direction. The detection airflow continuously output from the detection air passage 32 is sprayed upward from the pneumatic detection hole 31. After being blocked by the bottom surface of the push block 45, the airflow changes direction and is shot from the gap between the bottom surface of the push block 45 and the top surface of the first positioning plate 42 to the top surface of the first positioning plate 42. This structural design makes the push block 45 form a physical shielding barrier against the pneumatic detection hole 31 when idle, effectively preventing the cutting fluid or iron filings splashed during the machining process from falling directly into the pneumatic detection hole 31 from above and causing blockage, thus ensuring the long-term stable operation of the detection air passage 32.

[0052] Specifically, the bottom surface of the push block 45 is provided with an outwardly expanding inclined surface 451. The outwardly expanding inclined surface 451 is preferably an arc-shaped curved surface structure protruding towards the first positioning disk 42, with its generatrix radiating outward from the central axis of the pneumatic detection hole 31. When the detection airflow is sprayed upward from the pneumatic detection hole 31 and contacts the outwardly expanding inclined surface 451 on the bottom surface of the push block 45, the airflow is blocked by the arc-shaped outwardly expanding inclined surface 451 and reflected along the arc surface. The reflected airflow then diffuses outward in a direction away from the center of the pneumatic detection hole 31. This design not only enhances the chip protection effect of the pneumatic detection hole 31 but also utilizes the outwardly diffused reflected airflow to actively sweep away fine debris near the top surface of the first positioning disk 42, forming a continuous airflow expulsion shielding layer above the top surface of the first positioning disk 42, further ensuring the cleanliness of the top surface of the first positioning disk 42.

[0053] Specifically, to fully utilize the air compression effect generated when the pusher block 45 is pressed in to achieve automatic chip removal, a purge channel 47 is provided inside the central positioning post 41. The purge channel 47 is an air passage located inside the central positioning post 41, with one end connected to the bottom of the receiving groove 44 and the other end extending downwards to the side wall of the central positioning post 41 near the first positioning disk 42. A purge hole 48 is provided circumferentially on the side wall of the central positioning post 41 at the junction of the first positioning disk 42 and the central positioning post 41. The purge hole 48 is preferably an elongated slit-like opening, extending circumferentially along the central positioning post 41 to ensure that the discharged chip-removing airflow covers as much of the top surface of the first positioning disk 42 as possible. The lower end of the purge channel 47 communicates with the purge hole 48.

[0054] When the steering knuckle 100 is lowered and the pusher 45 is pressed inward into the receiving groove 44, the cavity volume of the receiving groove 44 is compressed, and the air inside the cavity is squeezed by the pusher 45. The compressed air flows downward along the blowing channel 47 and is ejected at high speed from the blowing hole 48, forming a pulsed chip removal airflow on the top surface of the first positioning plate 42. This chip removal airflow can blow away any iron filings that may remain on the top surface of the first positioning plate 42, ensuring the cleanliness of the top surface of the first positioning plate 42 before the steering knuckle 100 is seated.

[0055] Specifically, a sloping guide design is preferably implemented inside the central positioning post 41, above the blow-out hole 48. When the push block 45 is instantly pressed into the receiving groove 44 by the steering knuckle 100, the air inside the receiving groove 44 is violently compressed. The compressed air flows downward through the blow-out channel 47 and, upon contact with the sloping guide structure, is better gathered and guided downward, forming a stronger and more concentrated chip-removing airflow that is discharged at high speed from the blow-out hole 48 to the top surface of the first positioning disk 42, thereby enhancing the chip removal effect. This design can directly utilize the instantaneous potential energy of the workpiece during unloading to squeeze the air out of the receiving groove 44, achieving chip removal by blowing away air from the top surface of the first positioning disk 42.

[0056] Specifically, when the steering knuckle 100 is removed after machining, the push block 45 is reset and ejected under the elastic force of the reset member 46. To prevent the generation of instantaneous negative pressure in the receiving groove 44 and the inhalation of external chips, the continuously discharged detection airflow in the detection air path 32 can form a positive pressure environment around the central positioning column 41, thereby effectively preventing external impurities from being sucked into the purging channel 47 or the receiving groove 44 by negative pressure, ensuring the long-term reliable operation of the detection air path and the mechanical structure.

[0057] Reference Figure 1 , Figure 10 and Figure 11 Because the bottom surface of the steering knuckle 100 has casting draft angles and uneven surface features, a floating support mechanism 50 is also provided on the base plate 10 to prevent bending deformation caused by forced compression at the top. The floating support mechanism 50 is installed on the base plate 10 and distributed around the periphery of the central positioning column 41, including a first support member 51, a second support member 52, a third support member 53, a fourth support member 54, and a fifth support member 55. Each support member of the floating support mechanism 50 is preferably a hydraulically driven floating support column, which has a hydraulic piston cylinder inside. The piston cylinder is connected to the hydraulic oil passage of the oil circuit system 20, and the top of the support column has a flat contact head to adapt to the irregular bottom surface contour of the steering knuckle 100.

[0058] Reference Figure 1 and Figure 10Specifically, the first support member 51 and the second support member 52 are disposed on the bottom side area of ​​the steering knuckle head 110, respectively supporting the steering knuckle head 110 from both sides; the third support member 53 is disposed on the bottom side area of ​​the steering knuckle middle 120, that is, the bottom surface position around the steering knuckle center hole 121; the fourth support member 54 and the fifth support member 55 are disposed on the bottom side area of ​​the steering knuckle tail 130, respectively supporting the steering knuckle tail 130 from both sides.

[0059] Reference Figure 7 , Figure 10 and Figure 11 To enhance the overall clamping rigidity during multi-angle cutting and prevent vibration caused by tool cutting, a peripheral clamping mechanism 60 is also provided on the base plate 10. The peripheral clamping mechanism 60 includes a first lever clamping member 61, a second lever clamping member 62, a first steering clamping member 63, and a second steering clamping member 64.

[0060] The first lever clamping member 61 is located on one side of the steering knuckle head 110 and is mounted on a support on the base plate 10 via a hinge shaft. It is driven by a hydraulic cylinder in the oil circuit system 20. The piston rod of the hydraulic cylinder pushes the lever arm to rotate around the hinge shaft, causing the clamping end of the lever arm to swing downward and clamp the top side of the steering knuckle head 110. The second lever clamping member 62 is located on one side of the steering knuckle middle 120. Its structure is similar to that of the first lever clamping member 61, and it also clamps the top side of the steering knuckle middle 120 downward through the lever principle.

[0061] The first steering clamping member 63 and the second steering clamping member 64 are sequentially disposed on the same side of the steering knuckle tail 130. Both are mounted on the base plate 10 via supports and are driven by hydraulic cylinders in the oil circuit system 20. The first steering clamping member 63 and the second steering clamping member 64 are preferably angle hydraulic cylinder type clamping members. When their piston rods extend, they first rotate a certain angle, preferably 90°, to rotate the clamping arm above the steering knuckle tail 130, and then push it axially downward to clamp the top side of the steering knuckle tail 130.

[0062] Specifically, refer to Figure 10 and Figure 11To limit the radial displacement and rotational freedom of the steering knuckle 100 in the horizontal plane, a first contouring positioning member 70 and a second contouring positioning member 80 are provided on the base plate 10. The first contouring positioning member 70 is installed on the side of the base plate 10 near the central positioning post 41, and is located at the center position enclosed by the first support member 51, the second support member 52, and the central positioning post 41. The first contouring positioning member 70 is preferably a contouring positioning post, which is fixed to the base plate 10 by bolts. The top shape of the first contouring positioning member 70 is adapted to the inner wall contour of the steering knuckle head fixing hole 111. When the steering knuckle 100 is lowered, the steering knuckle head fixing hole 111 fits into the top of the first contouring positioning member 70, and the first contouring positioning member 70 abuts against the inner wall of the steering knuckle head fixing hole 111, limiting the displacement of the steering knuckle head 110 in the horizontal plane.

[0063] Reference Figure 7 and Figure 11 The second contour positioning element 80 is disposed on the base plate 10 on the side away from the central positioning post 41 and is fixed to the base plate 10 by bolts. The second contour positioning element 80 is preferably a positioning post structure, with its sidewall machined into an arc-shaped contact surface that matches the arc-shaped contour of the corresponding position of the steering knuckle tail 130. When the steering knuckle 100 is positioned, the arc-shaped contact surface of the second contour positioning element 80 abuts against the outer arc-shaped contour of the steering knuckle tail 130, restricting the displacement of the steering knuckle tail 130 in the horizontal plane. The first contour positioning element 70 and the second contour positioning element 80 together restrict the rotational freedom of the steering knuckle 100 around the central positioning post 41 from both ends, achieving precise radial pre-positioning at both ends.

[0064] Reference Figure 1 , Figure 10 Hehe Figure 11 In this embodiment, to achieve more comprehensive radial positioning of the irregularly shaped steering knuckle 100, a head positioning post 71 is provided on the outer wall of the first contour positioning member 70. The head positioning post 71 is located on the side of the first contour positioning member 70 away from the central positioning post 41. The head positioning post 71 is preferably a hydraulically driven telescopic positioning post, which is used to abut against the bottom side of the steering knuckle head 110 for auxiliary support positioning. A tail support post 81 is provided on the second contour positioning member 80. The tail support post 81 is located on the side of the second contour positioning member 80 near the central positioning post 41. The tail support post 81 is also preferably a hydraulically driven telescopic support post, and the top of the support post is provided with a ball head contact head, which is adapted to the inner wall of the steering knuckle tail fixing hole 131 for abutting against the steering knuckle tail fixing hole 131 for auxiliary support positioning. Both the head positioning post 71 and the tail support post 81 are driven and controlled by the hydraulic control valve group of the oil circuit system 20 to provide all-round radial positioning assistance for the steering knuckle 100.

[0065] Specifically, the floating support mechanism 50, the head positioning column 71, and the tail support column 81 are all in a low-position retracted state in the initial state. When the control system receives the seat positioning signal and drives the gripper 43 to clamp, the hydraulic system 20 controls the operation of each support component in sequence according to the preset timing program: First, the head positioning column 71 rises upward to abut the bottom side of the steering knuckle head 110; then, the first support component 51 rises upward to abut the bottom surface of the steering knuckle head 110; next, the second support component 52 rises upward; then, the third support component 53 rises upward to abut the bottom surface of the steering knuckle middle 120; after that, the fourth support component 54 and the fifth support component 55 rise upward in sequence to abut the bottom surface of the steering knuckle tail 130; finally, the tail support column 81 rises upward to abut the steering knuckle tail fixing hole 131. After each support component's hydraulic piston cylinder end contacts the bottom surface of the steering knuckle 100, the hydraulic lock valve in the hydraulic control valve group closes via the self-locking function of the hydraulic system, locking the support component in its current raised position and forming a rigid support point. Through the above-mentioned sequential actions, gradual contact, and individual locking, the five floating support components, along with the head positioning column 71 and the tail support column 81, together constitute a stable, rigid bottom support that adapts to the irregular bottom contour of the steering knuckle 100.

[0066] The peripheral clamping mechanism 60 operates strictly after the floating support mechanism 50. After all the supporting components of the floating support mechanism 50 have been raised and hydraulically self-locked, the hydraulic system 20 then controls the first lever clamping component 61 to press down on the top side of the steering knuckle head 110, the second lever clamping component 62 to press down on the top side of the steering knuckle middle 120, the first steering clamping component 63 to press down on the top side of the steering knuckle tail 130, and the second steering clamping component 64 to press down on the top side of the steering knuckle tail 130, according to a preset timing sequence. The downward clamping force applied to the steering knuckle 100 by the peripheral clamping mechanism 60 and the upward supporting force applied to the steering knuckle 100 by the floating support mechanism 50 create a vertically opposing clamping force, firmly holding the steering knuckle 100 between the two forces, achieving flexible positioning and clamping of the steering knuckle 100 from all directions and multiple angles.

[0067] The implementation principle of a multi-angle machining tooling fixture for steering knuckles in this application embodiment is as follows: First, the operator or robot aligns the steering knuckle center hole 121 of the steering knuckle 100 with the center positioning post 41, while simultaneously aligning the steering knuckle head fixing hole 111 with the first contour positioning member 70 and the steering knuckle tail 130 with the arc-shaped contact surface of the second contour positioning member 80, and then lowers the steering knuckle 100. During the descent, the inner wall of the steering knuckle center hole 121 contacts the inclined guide surface of the outer surface of the three push blocks 45, and the steering knuckle 100 slides smoothly down along the inclined guide surface. Then, the steering knuckle 100, relying on its own weight, pushes the three push blocks 45 radially inward into their respective receiving grooves 44. The moment the pusher block 45 is pressed in, the air in each receiving groove 44 is violently compressed. The compressed air flows downward through each blowing channel 47, and after contacting the inclined guide structure above the blowing hole 48 inside the central positioning post 41, it is gathered and guided, and ejected from each blowing hole 48 as a high-speed airflow, directly blowing away any iron filings that may remain on the positioning surface. At the same time, the detection airflow continuously output from the detection air path 32 is discharged upward through each pneumatic detection hole 31. It is blocked and reflected by the arc-shaped outwardly expanding inclined surface 451 at the bottom of the pusher block 45, and the reflected airflow is blown towards the outer edge area of ​​the top surface of the first positioning plate 42, further realizing the anti-clogging protection of the pneumatic detection holes 31 and the auxiliary cleaning of the top surface of the first positioning plate 42. Then, the steering knuckle 100 continues to fall until its bottom surface is completely in contact with the top surface of the first positioning plate 42, and the bottom surface of the steering knuckle 100 completely seals the three pneumatic detection holes 31. The air pressure in the detection air circuit 32 rapidly rises to a preset threshold. After the air pressure detection element 33 detects that the air pressure has reached the standard, it sends a seat positioning signal to the control system. Upon receiving the seat positioning signal, the control system outputs a trigger command, controlling the hydraulic control valve group of the oil circuit system 20 to switch direction, driving the hydraulic tie rod inside the center positioning column 41 to move. The three grippers 43 simultaneously expand radially, firmly locking the center hole 121 of the steering knuckle. After the grippers 43 have clamped, the oil circuit system 20 controls the first positioning column 71, the first support member 51, the second support member 52, the third support member 53, the fourth support member 54, the fifth support member 55, and the rear support column 81 to float and lift upward one by one according to a preset timing sequence. After the hydraulic piston cylinder of each support member adaptively and flexibly abuts against the uneven bottom surface of the steering knuckle 100 at its support end, the hydraulic lock valve closes to perform hydraulic self-locking, and each support member is locked in its respective raised position, together forming a solid bottom rigid support. Once the floating support mechanism 50 is fully locked, the hydraulic system 20 sequentially controls the first lever clamping member 61 to press down on the top side of the steering knuckle head 110, the second lever clamping member 62 to press down on the top side of the steering knuckle middle 120, and the first steering clamping member 63 and the second steering clamping member 64 to press down on the top side of the steering knuckle tail 130 in sequence. The downward clamping force provided by the outer clamping mechanism 60 and the upward supporting force provided by the floating support mechanism 50 form a counterbalance in the vertical direction, and the steering knuckle 100 is flexibly clamped in all directions, without generating bending stress inside.At this point, the positioning and clamping are complete, and the spindle of the five-axis CNC machining center can begin multi-angle heavy-duty milling. After machining, the components are released in reverse order of clamping: first, the outer clamping mechanism 60 is released, followed by the second steering clamping component 64, the first steering clamping component 63, the second lever clamping component 62, and the first lever clamping component 61. Then, the floating support mechanism 50 is released, and the tail support column 81, the fifth support component 55, the fourth support component 54, the third support component 53, the second support component 52, the first support component 51, and the head positioning column 71 retract sequentially. Finally, the gripper 43 is released. The push block 45 pops out and resets under the elastic force of the reset component 46. The arc-shaped outwardly expanding inclined surface 451 at the bottom of the push block 45 hovers again to shield and protect the pneumatic detection holes 31. The fixture returns to standby mode, awaiting the placement of the next workpiece.

[0068] The above are all preferred embodiments of this application, and are not intended to limit the scope of protection of this application. Therefore, all equivalent changes made in accordance with the structure, shape and principle of this application should be covered within the scope of protection of this application.

Claims

1. A machine tool fixture for multi-angle machining of steering knuckles, characterized in that, include: A base plate (10) is provided with an oil circuit system (20); The center positioning mechanism (40) includes a center positioning column (41) vertically mounted on the base plate (10) and a gripper (43) mounted on the top of the center positioning column (41). The center positioning column (41) is provided with a first positioning disc (42) around its periphery for supporting the bottom side of the steering knuckle (100). The gripper (43) is connected to the oil circuit system (20). The oil circuit system (20) is used to control the gripper (43) to clamp the steering knuckle (100) from the center of the steering knuckle (100). An airtightness testing mechanism (30) includes a testing air path (32), which is connected to a pressure testing element (33). The top surface of the first positioning disk (42) is provided with a pneumatic testing hole (31) that communicates with the testing air path (32). The control system is electrically connected to the air pressure detection element (33) and the oil circuit system (20), and the control system is configured as follows: In response to receiving a seated signal from the air pressure detection element (33), the hydraulic system (20) is triggered to drive the gripper (43) to clamp the steering knuckle (100); wherein, the seated signal corresponds to the steering knuckle (100) being seated on the first positioning plate (42) to block the pneumatic detection hole (31) and causing the air pressure in the detection air passage (32) to rise to a preset threshold. If the pneumatic detection hole (31) is not completely blocked, resulting in the failure to receive the seat position signal, the control system will not output a trigger command so that the gripper (43) remains in the released state.

2. The tooling fixture for multi-angle machining of steering knuckles according to claim 1, characterized in that, A receiving groove (44) is provided circumferentially on the outer wall of the central positioning post (41) between the gripper (43) and the first positioning disk (42). A push block (45) is slidably fitted in the receiving groove (44). A reset member (46) is provided between the push block (45) and the inner wall of the receiving groove (44). The reset member (46) provides elastic potential energy to the push block (45) to move away from the receiving groove (44) so ​​that when the steering knuckle (100) is placed, the gravity of the steering knuckle (100) presses the push block (45) to overcome the elastic potential energy of the reset member (46) and move it closer to the inner wall of the receiving groove (44). The push block (45) abuts against the inner side wall of the steering knuckle center hole (121) for center positioning.

3. The tooling fixture for multi-angle machining of steering knuckles according to claim 2, characterized in that, When the steering knuckle (100) is not positioned, the bottom surface of the push block (45) is above the pneumatic detection hole (31). When the airflow in the detection air passage (32) is sprayed upward through the pneumatic detection hole (31), the airflow is blocked by the bottom surface of the push block (45) and thus shot towards the top surface of the first positioning plate (42).

4. The multi-angle machining fixture for steering knuckles according to claim 3, characterized in that, The bottom surface of the pusher (45) is provided with an outwardly expanding inclined surface (451) so that the airflow reflected by the outwardly expanding inclined surface (451) is sprayed away from the center of the pneumatic detection hole (31).

5. The tooling for machining steering knuckles at multiple angles according to claim 2, characterized in that, A blowing channel (47) is provided inside the central positioning post (41). A blowing hole (48) is provided circumferentially on the side wall of the central positioning post (41) near the first positioning disk (42). One end of the blowing channel (47) is connected to the receiving groove (44), and the other end is connected to the blowing hole (48), so that the push block (45) squeezes the air in the receiving groove (44) and sprays it out from the blowing hole (48) through the blowing channel (47), forming a chip removal airflow on the top surface of the first positioning disk (42).

6. The tooling for multi-angle machining of steering knuckles according to claim 1, characterized in that, It also includes a floating support mechanism (50), which is mounted on the base plate (10) and distributed around the central positioning post (41). The floating support mechanism (50) is driven by the oil circuit system (20). The floating support mechanism (50) is used to support the steering knuckle (100). The floating support mechanism (50) is controlled to rise upward to abut against the bottom surface of the steering knuckle (100) away from the gripper (43).

7. The multi-angle machining fixture for steering knuckles according to claim 6, characterized in that, The floating support mechanism (50) includes a first support member (51), a second support member (52), a third support member (53), a fourth support member (54), and a fifth support member (55); the first support member (51) and the second support member (52) are used to position the bottom side of the head of the steering knuckle (110), the third support member (53) is used to position the bottom side of the middle part (120) of the steering knuckle, and the fourth support member (54) and the fifth support member (55) are used to position the bottom side of the tail of the steering knuckle (130); the first support member (51), the second support member (52), the third support member (53), the fourth support member (54), and the fifth support member (55) can move sequentially to support the bottom side of the steering knuckle (100).

8. The multi-angle machining fixture for steering knuckles according to claim 6, characterized in that, It also includes an external clamping mechanism (60), which is mounted on the base plate (10) and driven by the oil circuit system (20). The external clamping mechanism (60) is used to press down the steering knuckle (100). The downward clamping force of the external clamping mechanism (60) and the upward supporting force of the floating support mechanism (50) form an up-and-down clamping tendency on the steering knuckle (100).

9. The multi-angle machining fixture for steering knuckles according to claim 8, characterized in that, The peripheral clamping mechanism (60) includes a first lever clamping member (61), a second lever clamping member (62), a first steering clamping member (63), and a second steering clamping member (64). The first lever clamping member (61) is used to clamp the top side of the steering knuckle head (110), the second lever clamping member (62) is used to clamp the top side of the steering knuckle middle (120), and the first steering clamping member (63) and the second steering clamping member (64) are used to clamp the top side of the steering knuckle tail (130). The first lever clamping member (61), the second lever clamping member (62), the first steering clamping member (63), and the second steering clamping member (64) can sequentially press down on the top side of the steering knuckle (100). When positioning, the floating support mechanism (50) moves first, and the peripheral clamping mechanism (60) moves later.

10. The multi-angle machining tooling fixture for steering knuckles according to claim 7, characterized in that, It also includes a first contour positioning component (70) and a second contour positioning component (80). The first contour positioning component (70) is mounted on the base plate (10) and is located at the center position enclosed by the floating support mechanism (50) and the central positioning column (41). The first contour positioning component (70) abuts against the head (110) of the steering knuckle. The second contour positioning component (80) is located on the side of the base plate (10) away from the central positioning column (41) and abuts against the tail (130) of the steering knuckle. The first contour positioning component (70) and the second contour positioning component (80) are used for radial positioning of the head and tail of the steering knuckle (100).

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