A fixing device and method for processing an EGR cooler support

Abstract

The application relates to the technical field of clamps, in particular to a fixing device and method for EGR cooler support machining, which comprises a base and an EGR cooler support, further comprises a supporting rod, the side surface of the supporting rod is provided with a lower expansion clamp used for abutting against the lower part of the side surface of the EGR cooler support and an upper expansion clamp used for abutting against the upper part of the side surface of the EGR cooler support, a gas supply mechanism is used for supplying gas to the lower expansion clamp and the upper expansion clamp, so that the lower expansion clamp and the upper expansion clamp are expanded to clamp the EGR cooler support; a sliding base is slidably arranged on the base and used for bearing the supporting rod; a locking mechanism is used for locking the position of the sliding base after the lower expansion clamp and the upper expansion clamp abut against the side surface of the EGR cooler support, the locking mechanism comprises a movable abutting rod arranged in the base and an arc plate arranged in the sliding base and abutting against the abutting rod, a driving assembly is arranged in the sliding base and is driven by the arc plate to provide power for the gas supply mechanism; a rigid adjusting mechanism comprises a double-end plug rod arranged in the supporting rod and an electric push rod used for driving the double-end plug rod to move.

Description

Technical Field

[0001] This invention relates to the field of fixture technology, specifically to a fixing device and method for machining EGR cooler brackets. Background Technology

[0002] As a core supporting component of the automotive engine emission control system, the EGR (Exhaust Gas Recirculation) cooler bracket's machining precision directly determines the sealing performance and long-term reliability of the EGR system. With the stringent implementation of China VI / Euro VI emission regulations, the manufacturing precision requirements for EGR cooler brackets are increasingly stringent, particularly the demanding standards of ≤0.05mm for the flatness of the mounting surface and ≤0.1mm for the positional accuracy of the holes. This presents unprecedented challenges to the machining process. EGR cooler brackets are typically manufactured using aluminum alloy die-casting, characterized by a typical thin-walled structure (3-8mm wall thickness), multi-curved irregular contours (including complex reinforcing ribs and mounting bosses), and uneven distribution of structural strength. During CNC machining, such workpieces are highly susceptible to micro-deformation due to uneven clamping force, leading to out-of-tolerance critical dimensions. In traditional machining, the deformation of thin-walled parts often reaches 0.1-0.15mm, far exceeding process requirements and resulting in a large number of scraps. Meanwhile, there is a datum conversion problem between the mounting surface and the machining surface of the bracket. The positioning datum of the traditional fixture is difficult to coincide with the design datum, and the repeatability error is generally ≥0.05mm, resulting in a vicious cycle of "inaccurate positioning and inaccurate machining".

[0003] For example, patent document CN223338887U discloses a fixing device for processing an EGR cooler bracket, including a support plate, two side positioning modules, positioning pins, and a bottom support rod. The support plate has connecting holes at both ends; a hollow area is provided on the support plate corresponding to the back of the EGR cooler bracket to be processed; the two side positioning modules are located on the upper surface of the support plate and on the same side; each side positioning module includes a vertical plate, a horizontal plate, and a first bolt; the top center of the vertical plate is recessed downwards, forming a recessed area; one inner end of the vertical plate is higher than the outer end; the horizontal plate is fixed to the outside of the vertical plate along the length of the support plate; the first bolt is horizontally threaded onto the horizontal plate along the width direction of the support plate; the positioning pin is fixed to the support plate; the top of the bottom support plate is horizontal. This patent allows for machining on both sides, accelerating processing efficiency.

[0004] In existing technologies, EGR cooler bracket machining commonly employs a single-sided bonding positioning module. While this design can achieve initial workpiece fixation, it has fundamental drawbacks in actual multi-face continuous machining scenarios: the bracket requires milling, drilling, and tapping of at least three machining surfaces, including the mounting surface, positioning hole system, and side reinforcing ribs, while traditional positioning modules can only provide rigid constraints on a single reference surface. Each time the workpiece is flipped for multi-face machining, a complete process of disassembly, repositioning, and clamping must be performed. Therefore, this application proposes a fixing device and method for EGR cooler bracket machining. Summary of the Invention

[0005] The purpose of this invention is to provide a fixing device and method for processing EGR cooler brackets, so as to solve the problems mentioned in the background art.

[0006] To achieve the above objectives, the present invention provides the following technical solution: a fixing device for processing an EGR cooler bracket, comprising a base and an EGR cooler bracket, and further comprising:

[0007] The support rod has a lower expansion clamp for abutting against the lower part of the side of the EGR cooler bracket and an upper expansion clamp for abutting against the upper part of the side of the EGR cooler bracket.

[0008] An air supply mechanism is used to supply air to the downward expansion clamp and the upper expansion clamp, causing them to expand and clamp the EGR cooler bracket.

[0009] A slide block, which is slidably mounted on a base, is used to support a support rod;

[0010] A locking mechanism is used to lock the position of the slide after the lower expansion clamp and the upper expansion clamp abut against the side of the EGR cooler bracket. It includes a movable abutment rod disposed in the base and an arc plate disposed in the slide that abuts against the abutment rod. The slide is provided with a drive assembly that provides power to the air supply mechanism by moving the arc plate.

[0011] The rigid adjustment mechanism includes a double-ended piston rod disposed within the support rod and an electric actuator for driving the double-ended piston rod to move.

[0012] Preferably, the air supply mechanism includes an air delivery chamber opened in the slide, one end of the air delivery chamber is connected to a telescopic air pipe connected to a support rod, the support rod has a damping slot connected to the lower expansion clamp inside, the support rod has a damping hole connected to the upper expansion clamp inside, a connecting pipe is connected between the lower expansion clamp and the upper expansion clamp, and a solenoid valve is fixedly connected inside the connecting pipe.

[0013] Preferably, the drive assembly includes an air cylinder disposed on both sides of the slide and communicating with the air supply chamber, and a pressure piston rod is slidably connected inside the air cylinder, with one end of the pressure piston rod away from its piston end being fixedly connected to the arc plate.

[0014] Preferably, the locking mechanism includes an air chamber formed within the base, a piston push rod slidably connected inside the air chamber, one end of the piston push rod being fixedly connected to a stop rod, a sleeve spring for driving the piston push rod to reset itself being sleeved on the outer surface of the piston push rod, an air distributor being fixedly connected to one side of the base, an air outlet end of the air distributor having an air supply hole communicating with the air chamber, and the two ends of the double-ended plug rod extending into the inner cavities of the lower expansion clamp and the upper expansion clamp, respectively.

[0015] Preferably, the rigid adjustment mechanism includes a variable cavity that is linked to the double-ended plunger, a side cavity that communicates with the variable cavity, a pressure rod that is slidably connected in the side cavity, a rocker arm that is hinged to the pressure rod, and a stop ball disposed at the free end of the rocker arm. The volume of the variable cavity changes with the movement of the double-ended plunger.

[0016] Preferably, the pressure rod and the rocker are connected by a universal joint.

[0017] Preferably, the top of the slide is slidably connected to a fine-tuning slide shoe that is fixedly connected to a support rod, and one side of the fine-tuning slide shoe is fixedly connected to a spring that is fixedly connected to the slide.

[0018] Preferably, the upper expansion clamp is slidably connected to the outer surface of the support rod, and a tension spring connected to the lower expansion clamp is connected to one side of the upper expansion clamp.

[0019] Preferably, the top of the base is provided with a sliding groove for the slide to slide.

[0020] The present invention also provides a fixing method for processing an EGR cooler bracket, comprising the following steps:

[0021] S1. Move at least one slide block to a preset position on the base, so that the upper expansion clamp and the lower expansion clamp on the support rod abut against the top and bottom of the side of the EGR cooler bracket, respectively;

[0022] S2. Drive the locking mechanism to lock the position of the slide block, and link the air supply mechanism to supply air to the upper expansion clamp and the lower expansion clamp, so that the two expand to clamp the EGR cooler bracket from the side.

[0023] S3. When machining the upper surface of the EGR cooler bracket, control the electric push rod to drive the double-ended plunger to move in the first direction to increase the support rigidity of the lower expansion clamp and correspondingly decrease the support rigidity of the upper expansion clamp. When machining the lower surface of the EGR cooler bracket, control the electric push rod to drive the double-ended plunger to move in the second direction opposite to the first direction to increase the support rigidity of the upper expansion clamp and correspondingly decrease the support rigidity of the lower expansion clamp.

[0024] Compared with the prior art, the beneficial effects of the present invention are:

[0025] 1. The sliding groove on the top of the base supports flexible layout of multiple slides. Combined with the stepless lateral adjustment mechanism consisting of fine-tuning slippers and springs, the clamping point precisely adapts to the irregular contours of the EGR cooler bracket's side curved surface and reinforcing ribs, completely eliminating local suspension or stress concentration caused by traditional rigid clamps. The upper and lower expansion clamps are made of highly elastic composite materials. Based on the initial contact force provided by the tension spring, the expansion amount is intelligently controlled by the air supply mechanism, so that the clamping force is evenly distributed in the thin-walled area, effectively suppressing processing deformation and ensuring the flatness of the mounting surface and the position accuracy of the holes; The dual-stage throttling structure formed by the nitrous oxide and damping slots endows the clamp with excellent shock absorption and buffering characteristics, significantly improving the surface quality of the finished product. In the locking mechanism, the mechanical locking action of the stop rod and the arc plate, together with the drive components, synchronously converts the locking process into air supply power, eliminating the need for an independent air circuit control link, achieving zero-delay response of air supply upon locking, and greatly improving clamping efficiency and process reliability. The solenoid valve and pressure sensor built into the series pipe work together to form an intelligent control closed loop, supporting dynamic switching between the soft buffer mode for roughing and the rigid locking mode for finishing, so that the clamping strategy can adapt and evolve according to process requirements.

[0026] 2. Through precise linkage between the double-ended plunger and the electric actuator, dynamic differential control of the rigidity of the upper and lower expansion clamps is achieved: When machining the upper surface of the EGR cooler bracket, the electric actuator drives the double-ended plunger to move downward, compressing the inner cavity volume of the lower expansion clamp to enhance its pressure-bearing rigidity, while simultaneously slightly increasing the volume of the upper expansion clamp to avoid over-constraint at the top; when machining the lower surface, the opposite adjustment is made to eliminate micro-deformation and unloading springback in thin-walled areas caused by clamping stress imbalance at the source. At the same time, the displacement of the double-ended plunger synchronously changes the variable cavity volume, driving the pressure rod in the side cavity to pull the rocker plate to rotate via the universal joint, so that the ball accurately contacts the weak area on the side of the bracket, such as the root of the reinforcing rib or the curved transition section, constructing a three-dimensional force system closed loop of longitudinal flexible clamping and lateral rigid support, effectively suppressing cutting vibration and lateral displacement. The universal joint gives the rocker plate adaptive angle adjustment capability, ensuring that the ball always perpendicularly fits the irregular contour surface, eliminating the risk of local indentation. Attached Figure Description

[0027] Figure 1 This is a three-dimensional structural diagram of the present invention;

[0028] Figure 2 This is a top view cross-sectional structural diagram of the base in this invention;

[0029] Figure 3 For the present invention Figure 2 Enlarged structural diagram at point A;

[0030] Figure 4 This is a side view sectional structural diagram of the base in this invention;

[0031] Figure 5 For the present invention Figure 4 Enlarged structural diagram at point B;

[0032] Figure 6 This is a schematic diagram of the support rod in this invention;

[0033] Figure 7 This is a partial cross-sectional structural diagram of the support rod in this invention;

[0034] Figure 8 This is a schematic cross-sectional view of the support rod in this invention;

[0035] Figure 9 This is a schematic cross-sectional view of the lower expansion clamp in this invention.

[0036] Figure 10 For the present invention Figure 9 Enlarged schematic diagram of the structure at point C.

[0037] In the diagram: 100, base; 101, EGR cooler bracket; 200, support rod; 201, upper expansion clamp; 202, lower expansion clamp; 203, damping hole; 204, connecting pipe; 205, solenoid valve; 206, tension spring; 207, damping slot; 208, pressure sensor; 300, slide; 301, fine-tuning slipper; 302, spring; 303, air delivery chamber; 304, telescopic air pipe. 305. Air cylinder; 306. Pressure piston rod; 307. Arc plate; 308. Air chamber; 309. Piston push rod; 310. Push rod; 311. Spring sleeve; 312. Air inlet; 313. Transfer groove; 314. Air distributor; 400. Double-ended plug rod; 401. Electric push rod; 402. Side chamber; 403. Pressure rod; 404. Rocker; 405. Ball stopper; 406. Universal joint; 407. Variable cavity. Detailed Implementation

[0038] 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.

[0039] Example 1: Please refer to Figure 1 - Figure 10 The present invention provides a technical solution: a fixing device for processing an EGR cooler bracket, comprising a base 100 and an EGR cooler bracket 101.

[0040] It also includes a support rod 200. The side of the support rod 200 is provided with a lower expansion clamp 202 for contacting the lower side of the EGR cooler bracket 101 and an upper expansion clamp 201 for contacting the upper side of the EGR cooler bracket 101. The upper expansion clamp 201 is slidably connected to the outer surface of the support rod 200. One side of the upper expansion clamp 201 is connected to a tension spring 206 connected to the lower expansion clamp 202. By setting the upper expansion clamp 201 to be slidably connected to the outer surface of the support rod 200, it can slide freely, and clamp the side of the EGR cooler bracket 101 between the upper expansion clamp 201 and the lower expansion clamp 202. At the same time, the tension spring 206 provides tension to make the upper expansion clamp 201 and the lower expansion clamp 202 move closer to each other. The upper expansion clamp 201 and the lower expansion clamp 202 can expand to increase their volume and further improve the support force and strength of the EGR cooler bracket 101.

[0041] It also includes an air supply mechanism for supplying air to the lower expansion clamp 202 and the upper expansion clamp 201 to expand them and clamp the EGR cooler bracket 101. By providing the air supply mechanism, air can be continuously supplied into the upper expansion clamp 201 and the lower expansion clamp 202 to expand them.

[0042] It also includes a slide block 300, which is slidably mounted on the base 100 to support the support rod 200. The top of the base 100 has a sliding groove 313 for the slide block 300 to slide. The top of the slide block 300 is slidably connected to a fine-tuning slipper 301 that is fixedly connected to the support rod 200. One side of the fine-tuning slipper 301 is fixedly connected to a spring 302 that is fixedly connected to the slide block 300. The sliding groove 313 allows the slide block 300 to slide and thus achieves assembly. At the same time, a single sliding groove 313 can slide multiple slide blocks 300, thereby achieving multi-point clamping when dealing with irregular parts of the EGR cooler bracket 101. The cooperation between the fine-tuning slipper 301 and the spring 302 can make a small adjustment to the position of the support rod 200, thereby achieving stepless adjustment of the lateral position of the upper expansion clamp 201 and the lower expansion clamp 202.

[0043] It also includes a locking mechanism for locking the position of the slide 300 after the lower expansion clamp 202 and the upper expansion clamp 201 abut against the side of the EGR cooler bracket 101. The mechanism includes a movable abutment 310 disposed within the base 100 and an arc plate 307 disposed within the slide 300 and abutting against the abutment 310. The slide 300 is provided with a drive assembly that provides power to the air supply mechanism by moving the arc plate 307. By setting the locking mechanism, the position of the slide 300 can be fixed, thereby improving the stability of the clamping of the upper expansion clamp 201 and the lower expansion clamp 202. The abutment 310 is connected within the base 100, and the arc plate 307 is connected within the slide 300. The friction generated by the mutual abutment of the two achieves the locking of the slide 300. The drive assembly can provide air source driving force to the air supply mechanism after the abutment 310 and the arc plate 307 are locked, realizing linkage.

[0044] Furthermore, the air supply mechanism includes an air delivery chamber 303 located within the slide 300. One end of the air delivery chamber 303 is connected to a telescopic air pipe 304 connected to the support rod 200. The support rod 200 has a damping slot 207 connected to the lower expansion clamp 202 and a damping hole 203 connected to the upper expansion clamp 201. A connecting pipe 204 connects the lower expansion clamp 202 and the upper expansion clamp 201. A solenoid valve 205 is fixedly connected inside the connecting pipe 204. Both the upper expansion clamp 201 and the lower expansion clamp 202 are equipped with pressure sensors 208 to detect their own air pressure. The damping holes 203 and damping slots 207 provided respectively provide damping force to suppress the backflow of gas and enable them to have a shock absorption function. The solenoid valve 205 can close the series pipe 204 to allow the upper expansion clamp 201 and the lower expansion clamp 202 to operate independently. At the same time, the solenoid valve 205 can be opened to connect the upper expansion clamp 201 and the lower expansion clamp 202 in series, so that they can compensate each other for gas when subjected to vibration.

[0045] Furthermore, the drive assembly includes an air cylinder 305 disposed on both sides of the slide 300 and communicating with the air delivery chamber 303. A pressure piston rod 306 is slidably connected inside the air cylinder 305. One end of the pressure piston rod 306 away from its piston end is fixedly connected to the arc plate 307. By setting the cooperation between the air cylinder 305 and the pressure piston rod 306, gas can be squeezed into the air delivery chamber 303 when the arc plate 307 is moved under force, thereby delivering gas into the support rod 200.

[0046] Furthermore, the locking mechanism includes an air chamber 308 opened in the base 100. A piston push rod 309 is slidably connected inside the air chamber 308. One end of the piston push rod 309 is fixedly connected to the abutment rod 310. A sleeve spring 311 is sleeved on the outer surface of the piston push rod 309 to drive it to reset. A gas distributor 314 is fixedly connected to one side of the base 100. The gas distributor 314 has an air supply hole 312 communicating with the air chamber 308 at its outlet end. By setting an external air source for the gas distributor 314, gas can be supplied to multiple air chambers 308 through the air supply hole 312, thereby pushing the piston push rod 309 to move, so that the abutment rod 310 abuts against the arc plate 307 to complete the locking.

[0047] Initial positioning: Place the EGR cooler bracket 101 on the reference surface of the base 100, slide the slide block 300 along the sliding groove 313 to the target position, the lower expansion clamp 202 contacts the lower side of the bracket, and the upper expansion clamp 201 initially fits the upper part under the action of the tension spring 206; the fine-tuning slipper 301 adaptively fine-tunes under the guidance of the spring 302 to eliminate the contour gap.

[0048] Locking and air supply linkage: An external air source supplies air to the air chamber 308 through the air distributor 314 and the air supply hole 312, which pushes the piston push rod 309 to drive the push rod 310 to extend and tightly press against the arc plate 307 on the side wall of the slide 300 to achieve mechanical locking; when the push rod 310 continues to advance, the arc plate 307 drives the pressure piston rod 306 to compress the gas in the air cylinder 305, which is then transported to the support rod 200 through the air supply chamber 303 and the telescopic air pipe 304.

[0049] Intelligent expansion clamping: Gas preferentially enters the lower expansion clamp 202 through the damping slot 207 to expand and fit, and then is diverted to the upper expansion clamp 201 through the series pipe 204; the pressure sensor 208 monitors the air pressure in real time, and when the set value is reached, the control system closes the solenoid valve 205 to make the two clamps independently maintain pressure and obtain rigid support; if vibration is encountered during processing, the solenoid valve 205 can be opened to make the gas dynamically compensate between the clamps and suppress micro-vibration.

[0050] Reset and unloading: After processing is completed and the air is released, the sleeve spring 311 pushes the piston rod 309 to reset, the stop rod 310 retracts, the arc plate 307 is released, the upper expansion clamp 201 and the lower expansion clamp 202 retract, and the workpiece is removed.

[0051] In summary, the sliding groove 313 on the top of the base 100 supports the flexible layout of multiple slides 300. Combined with the stepless lateral adjustment mechanism formed by the fine-tuning slipper 301 and the spring 302, the clamping point can accurately adapt to the irregular contours of the side curved surface and reinforcing ribs of the EGR cooler bracket 101, completely eliminating the local suspension or stress concentration caused by traditional rigid clamps. The upper expansion clamp 201 and the lower expansion clamp 202 are made of highly elastic composite materials. Based on the initial contact force provided by the tension spring 206, the expansion amount is intelligently controlled by the air supply mechanism, so that the clamping force is evenly distributed in the thin-walled area, effectively suppressing processing deformation and ensuring the flatness of the mounting surface and the position of the holes. The damping hole 203 and the damping slot 207 form a two-stage throttling structure, giving the clamp excellent shock absorption and buffering characteristics, significantly improving the surface quality of the finished product. In the locking mechanism, the mechanical locking action of the stop rod 310 and the arc plate 307, together with the drive component, synchronously converts the locking process into air supply power, eliminating the need for an independent air circuit control link, realizing zero-delay response of air supply upon locking, and greatly improving clamping efficiency and process reliability. The solenoid valve 205 built into the series pipe 204 and the pressure sensor 208 work together to form an intelligent control closed loop, supporting dynamic switching between the roughing soft buffer mode and the finishing rigid locking mode, so that the clamping strategy can adapt and evolve with process requirements.

[0052] Example 2: Please refer to Figure 1 - Figure 10 The present invention also provides a technical solution, which differs from the technical solution of Embodiment 1 as follows: a fixing device for processing EGR cooler bracket, which further includes a rigidity adjustment mechanism, including a double-ended plunger 400 disposed in the support rod 200 and an electric push rod 401 for driving its movement. The two ends of the double-ended plunger 400 extend into the inner cavity of the lower expansion clamp 202 and the upper expansion clamp 201, respectively. By moving the double-ended plunger 400, the volume of the corresponding inner cavity at both ends can be changed, thereby adjusting the rigidity of the lower expansion clamp 202 and the upper expansion clamp 201 respectively.

[0053] Furthermore, the rigid adjustment mechanism includes a variable cavity 407 that is linked to the double-ended plunger 400, a side cavity 402 that communicates with the variable cavity 407, a pressure rod 403 that is slidably connected in the side cavity 402, a rocker plate 404 that is hinged to the pressure rod 403, and a ball stop 405 that is disposed at the free end of the rocker plate 404. The volume of the variable cavity 407 changes with the movement of the double-ended plunger 400. The pressure rod 403 and the rocker plate 404 are connected by a universal joint 406. By setting the variable cavity 407, its internal volume can be changed after the double-ended plunger 400 moves, thereby squeezing or pushing the gas flow, thereby changing the position of the pressure rod 403 and adjusting the position of the ball stop 405. This makes the ball stop 405 abut against the side of the EGR cooler bracket 101 when it is being processed, further improving its fixing strength.

[0054] The volume of the corresponding inner cavity at both ends is changed by moving the double-ended plunger 400, which in turn changes the volume of the variable cavity 407.

[0055] Surface finishing scenarios such as milling mounting surfaces:

[0056] The cutting force acts vertically downward on the EGR cooler bracket 101, triggering the electric push rod 401 to pull the double-ended piston rod 400 downward;

[0057] Longitudinal rigidity control: The volume of the inner cavity of the lower expansion clamp 202 is compressed, and the gas density increases, which improves its rigidity and strengthens its pressure-bearing capacity; at the same time, the volume of the upper expansion clamp 201 is slightly increased, reducing its constraint rigidity and avoiding micro-warping of the thin-walled area caused by excessive constraint in the upper part.

[0058] Lateral force system construction: The double-ended plunger 400 moves down, reducing the volume of the variable cavity 407. The gas pushes the pressure rod 403 outward through the gas path. The torque is transmitted through the universal joint 406 to drive the rocker 404 to rotate counterclockwise. The ball 405 precisely contacts the weak area on the side of the EGR cooler bracket 101, such as the root of the reinforcing rib, to provide lateral reaction force and suppress the lateral displacement caused by milling vibration.

[0059] Lower surface machining scenarios, such as drilling bottom positioning holes:

[0060] The electric actuator 401 pushes the double-ended piston rod 400 upward, enhancing the rigidity of the upper expansion clamp 201 to resist the upward cutting force. At the same time, the ball stop 405 presses against the bracket from the opposite side, forming a three-dimensional force system closed loop of upper pressure, lower support, and lateral resistance.

[0061] Specifically, when turning the upper surface of the EGR cooler bracket 101, the cutting force presses downwards, increasing the load-bearing capacity of the lower expansion clamp 202. At this time, the electric actuator 401 pulls the double-ended stopper 400 downwards, thereby compressing the internal space of the lower expansion clamp 202 to provide stronger rigid support. Simultaneously, the downward movement of the double-ended stopper 400 slightly reduces the rigidity of the upper expansion clamp 201 to prevent over-constraint. When turning the lower surface of the EGR cooler bracket 101, the electric actuator... The push rod 401 pushes the double-ended plug rod 400 upward, increasing the rigidity of the upper expansion clamp 201 and decreasing the rigidity of the lower expansion clamp 202. At the same time, the movement of the double-ended plug rod 400 will change the gas storage space in the variable cavity 407, thereby pushing or pulling the pressure rod 403 to move, causing the universal joint 406 to pull one end of the rocker arm 404 to move and rotate, so that the ball 405 abuts against the side of the EGR cooler bracket 101, providing lateral support and suppressing the lateral force generated during processing.

[0062] In summary, through the precise linkage of the double-ended plunger 400 and the electric push rod 401, dynamic differential control of the rigidity of the upper expansion clamp 201 and the lower expansion clamp 202 is achieved: when machining the upper surface of the EGR cooler bracket 101, the electric push rod 401 drives the double-ended plunger 400 to move downward, compressing the inner cavity volume of the lower expansion clamp 202 to enhance the pressure-bearing rigidity, and simultaneously slightly increasing the volume of the upper expansion clamp 201 to avoid over-constraint at the upper part; when machining the lower surface, the opposite adjustment is made to eliminate micro-deformation and unloading springback in the thin-walled area caused by the imbalance of clamping stress from the root. At the same time, the displacement of the double-ended plunger 400 synchronously changes the volume of the variable cavity 407, driving the pressure rod 403 in the side cavity 402 to pull the rocker 404 to rotate via the universal joint 406, so that the ball 405 accurately contacts the weak area on the side of the bracket, such as the root of the reinforcing rib or the curved transition section, constructing a three-dimensional force system closed loop of longitudinal flexible clamping and transverse rigid support, effectively suppressing cutting vibration and lateral displacement. Universal joint 406 gives rocker 404 adaptive angle adjustment capability, ensuring that ball stop 405 always fits vertically against irregular contour surface, eliminating the risk of local indentation.

[0063] Example 3: Please refer to Figure 1 - Figure 10 The present invention also provides a technical solution, which differs from the technical solution of Embodiment 1 as follows: a fixing method for processing an EGR cooler bracket, comprising the following steps:

[0064] S1. During use, the slide block 300 is slid into the transfer groove 313, so that the support rod 200 placed on top of it abuts against the side of the EGR cooler bracket 101. At the same time, the lower expansion clamp 202 on the surface of the support rod 200 abuts against the bottom of the side of the EGR cooler bracket 101, while the upper expansion clamp 201 on the surface of the support rod 200 abuts against the top of the side of the EGR cooler bracket 101, thereby achieving initial positioning.

[0065] S2. The gas distributor 314 is connected to an external gas source. High-pressure gas is delivered to the gas chamber 308 through the gas distributor 314 and the gas delivery port 312. As the gas pressure in the gas chamber 308 increases, it will push the piston rod 309 to move, which in turn will drive the push rod 310 to move and abut against the arc plate 307 on the side of the slide 300, thereby fixing the slide 300.

[0066] S3. As the push rod 310 continues to move, the piston end of the compression piston rod 306 moves within the air cylinder 305, thereby pushing the gas in the air cylinder 305 to be transported through the air delivery chamber 303 to the telescopic air pipe 304. After the gas enters the support rod 200 through the telescopic air pipe 304, it will first flow into the lower expansion clamp 202 to expand and increase the supporting force on the EGR cooler bracket 101. The gas will then be diverted to the upper expansion clamp 201 through the connecting pipe 204, so that the upper expansion clamp 201 expands synchronously. Afterwards, the solenoid valve 205 can be closed so that the upper expansion clamp 201 and the lower expansion clamp 202 obtain rigid support force.

[0067] S4. When turning the upper surface of the EGR cooler bracket 101, the cutting force will press downward and increase the load-bearing capacity of the lower expansion clamp 202. At this time, the electric push rod 401 is operated to pull the double-ended plug rod 400 downward, thereby compressing the space inside the lower expansion clamp 202 to make it obtain stronger rigid support. At the same time, the downward movement of the double-ended plug rod 400 will slightly reduce the rigidity of the upper expansion clamp 201 to prevent over-constraint. When turning the lower surface of the EGR cooler bracket 101, the electric push rod 401 can be operated to push the double-ended plug rod 400 upward, increasing the rigidity of the upper expansion clamp 201 and reducing the rigidity of the lower expansion clamp 202.

[0068] S5. Simultaneously, the movement of the double-ended plunger 400 will change the gas storage space in the variable cavity 407, thereby pushing or pulling the pressure rod 403 to move, causing the universal joint 406 to pull one end of the rocker plate 404 to move and rotate, thereby allowing the ball 405 to abut against the side of the EGR cooler bracket 101, providing lateral support and suppressing the lateral force generated during processing.

[0069] It should be noted that, in this document, relational terms such as "first" and "second" are used only to distinguish one entity or operation from another, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Furthermore, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such process, method, article, or apparatus.

[0070] Although embodiments of the invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the invention, the scope of which is defined by the appended claims and their equivalents.

Claims

1. A fixing device for machining an EGR cooler bracket, comprising a base (100) and an EGR cooler bracket (101), characterized in that, Also includes: Support rod (200), the side of which is provided with a lower expansion clamp (202) for contacting the lower part of the side of the EGR cooler bracket (101) and an upper expansion clamp (201) for contacting the upper part of the side of the EGR cooler bracket (101). An air supply mechanism is provided for supplying air to the downward expansion clamp (202) and the upper expansion clamp (201) to expand them and clamp the EGR cooler bracket (101). A slide (300) is slidably disposed on a base (100) for supporting a support rod (200). A locking mechanism is used to lock the position of the slide (300) after the lower expansion clamp (202) and the upper expansion clamp (201) abut against the side of the EGR cooler bracket (101). The mechanism includes a movable abutment (310) disposed in the base (100) and an arc plate (307) disposed in the slide (300) and abutting against the abutment (310). The slide (300) is provided with a drive assembly that provides power to the air supply mechanism by moving the arc plate (307). The rigid adjustment mechanism includes a double-ended piston rod (400) disposed in the support rod (200) and an electric actuator (401) for driving the double-ended piston rod (400) to move. The gas supply mechanism includes a gas delivery chamber (303) opened in the slide (300), one end of the gas delivery chamber (303) is connected to a telescopic air pipe (304) connected to the support rod (200), the support rod (200) has a damping slot (207) connected to the lower expansion clamp (202) inside, the support rod (200) has a damping hole (203) connected to the upper expansion clamp (201) inside, a connecting pipe (204) is connected between the lower expansion clamp (202) and the upper expansion clamp (201), and a solenoid valve (205) is fixedly connected inside the connecting pipe (204). The rigid adjustment mechanism includes a variable cavity (407) that is linked to the double-ended plunger (400), a side cavity (402) that communicates with the variable cavity (407), a pressure rod (403) that is slidably connected in the side cavity (402), a rocker (404) that is hinged to the pressure rod (403), and a stop ball (405) that is disposed at the free end of the rocker (404). The volume of the variable cavity (407) changes by the movement of the double-ended plunger (400).

2. The fixing device for machining an EGR cooler bracket according to claim 1, characterized in that: The drive assembly includes an air cylinder (305) disposed on both sides of the slide (300) and communicating with the air delivery chamber (303). A pressure piston rod (306) is slidably connected inside the air cylinder (305), and one end of the pressure piston rod (306) away from its piston end is fixedly connected to the arc plate (307).

3. The fixing device for machining an EGR cooler bracket according to claim 1, characterized in that: The locking mechanism includes an air chamber (308) opened in the base (100), a piston push rod (309) is slidably connected inside the air chamber (308), one end of the piston push rod (309) is fixedly connected to the push rod (310), and a sleeve spring (311) is sleeved on the outer surface of the piston push rod (309) to drive its own reset. A gas distributor (314) is fixedly connected to one side of the base (100), and the gas distributor (314) has an air supply hole (312) communicating with the air chamber (308) at the air outlet end. The two ends of the double-ended plug rod (400) extend into the inner cavity of the lower expansion clamp (202) and the upper expansion clamp (201), respectively.

4. The fixing device for machining an EGR cooler bracket according to claim 1, characterized in that: The pressure rod (403) and the rocker (404) are connected by a universal joint (406).

5. The fixing device for machining an EGR cooler bracket according to claim 1, characterized in that: The top of the slide (300) is slidably connected to a fine-tuning slide shoe (301) which is fixedly connected to the support rod (200), and a spring (302) which is fixedly connected to the slide (300) is fixedly connected to one side of the fine-tuning slide shoe (301).

6. The fixing device for machining an EGR cooler bracket according to claim 1, characterized in that: The upper expansion clamp (201) is slidably connected to the outer surface of the support rod (200), and a tension spring (206) connected to the lower expansion clamp (202) is connected to one side of the upper expansion clamp (201).

7. The fixing device for machining an EGR cooler bracket according to claim 1, characterized in that: The top of the base (100) is provided with a sliding groove (313) for the slide (300) to slide.

8. A fixing method for machining an EGR cooler bracket, and a fixing device for machining an EGR cooler bracket according to any one of claims 1-7, characterized in that: S1. Move at least one slide (300) to a preset position on the base (100) so that the upper expansion clamp (201) and lower expansion clamp (202) on the support rod (200) abut against the top and bottom of the side of the EGR cooler bracket (101), respectively. S2. Drive the locking mechanism to lock the position of the slide (300) and link the air supply mechanism to supply air to the upper expansion clamp (201) and the lower expansion clamp (202) so that they expand to clamp the EGR cooler bracket (101) from the side. S3. When machining the upper surface of the EGR cooler bracket (101), the electric push rod (401) is controlled to drive the double-ended plunger (400) to move in the first direction to increase the support rigidity of the lower expansion clamp (202) and correspondingly decrease the support rigidity of the upper expansion clamp (201). When machining the lower surface of the EGR cooler bracket (101), the electric push rod (401) is controlled to drive the double-ended plunger (400) to move in the second direction opposite to the first direction to increase the support rigidity of the upper expansion clamp (201) and correspondingly decrease the support rigidity of the lower expansion clamp (202).

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