A hydraulic punching device for aluminum die K plate

Abstract

The application discloses a hydraulic driving punching device for aluminum mold K plate and relates to the technical field of aluminum mold K plate punching, which comprises a workbench, a hydraulic punching mechanism arranged above the workbench and a hydraulic motor assembly, the hydraulic punching mechanism comprises a mounting seat, a hydraulic cylinder and a K plate hole die, the K plate hole die comprises a lower die seat and a punch driven by the hydraulic cylinder, a material stripping column is arranged outside the punch, the hydraulic cylinder is a double-section hydraulic cylinder, and a material pressing piston column and a punching piston column which can independently move relative to each other are arranged in the hydraulic cylinder. The application improves the problems in the prior art, such as the fact that the edge of a bolt fixing hole is often deformed upward due to the increased friction force of the punch sidewall wear during the hydraulic punching process of the aluminum mold K plate, and the fact that the connection quality is affected. The application has the advantages that the material stripping column and the punch sequentially act through hydraulic driving, the stable pressing force of the workpiece is maintained during the tool withdrawal stage, the upward deformation of the hole edge during the tool withdrawal is effectively prevented, and the punching quality is improved.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of aluminum mold K plate punching, in particular to a hydraulic driving punching device for aluminum mold K plate. BACKGROUND

[0002] The aluminum mold K plate is a key component of the building aluminum mold plate system, and is a core accessory for ensuring the accurate erection of the high-rise building outer wall mold. In the processing of the aluminum mold K plate, bolt fixing holes for connection need to be punched thereon, and the processing quality of the holes is crucial, and the flatness of the hole mouth directly affects the fastening effect of the subsequent bolt and the stability of the entire mold system.

[0003] In the prior art, the punching of the aluminum mold K plate generally adopts hydraulic punching technology, such as a kind of aluminum mold K plate automatic punching machine with application number 201910728060.8, that is, the punch is driven downward by the hydraulic cylinder to cooperate with the lower die to complete the blanking. However, in this dynamic process, the side wall of the punch will continuously rub against the inner wall of the product hole just formed. With the long-time operation of the equipment, the side wall of the punch and the cutting edge will inevitably be worn, resulting in a significant increase in the friction between them and the hole wall. When the friction force accumulates to a certain extent, in the moment when the punch completes the blanking and retreats upward, the excessive friction force will drive the plate material at the hole mouth to be raised upward, resulting in local "upward convex" deformation of the edge of the bolt fixing hole. This uneven defect will directly affect the smooth installation and effective locking of the bolt. In order to ensure the final quality, an additional leveling process often needs to be added, which not only increases the production cost, but also reduces the overall processing efficiency.

[0004] In view of the above technical problems, the present application discloses a hydraulic driving punching device for aluminum mold K plate, which has the advantages of sequential action of the stripper post and the punch driven by hydraulic pressure, maintaining stable pressing force on the workpiece during the tool withdrawal stage, effectively preventing upward convex deformation of the hole edge during tool withdrawal, and improving punching quality. SUMMARY

[0005] The present application aims to overcome the shortcomings of the prior art and provides a hydraulic driving punching device for aluminum mold K plate to solve the technical problems in the prior art that the increased friction force during tool withdrawal due to the wear of the side wall of the punch often causes upward convex deformation of the edge of the bolt fixing hole, thereby affecting the connection quality and increasing the leveling process. The present application has the advantages of sequential action of the stripper post and the punch driven by hydraulic pressure, maintaining stable pressing force on the workpiece during the tool withdrawal stage, effectively preventing upward convex deformation of the hole edge during tool withdrawal, and improving punching quality.

[0006] The hydraulic punching device for the aluminum mold K plate is characterized in that the hydraulic punching device comprises a workbench, a hydraulic punching mechanism arranged above the workbench and a hydraulic motor assembly, the hydraulic punching mechanism comprises a mounting seat, a hydraulic cylinder and a K plate hole die, the K plate hole die comprises a lower die seat and a punch driven by the hydraulic cylinder, the punch is externally sleeved with a stripping column, the hydraulic cylinder is a double-section hydraulic cylinder, and a pressing piston column and a punching piston column capable of moving independently relative to each other are arranged in the hydraulic cylinder.

[0007] The pressing piston column is drivingly connected with the stripping column, and the punching piston column is drivingly connected with the punch.

[0008] The device is provided with a hydraulic oil circuit which is configured to be capable of controlling the pressing piston column and the punching piston column to perform sequential actions, so that the stripping column first presses the workpiece tightly during punching, and then the punch performs punching.

[0009] Further, a telescopic cavity is formed in the pressing piston column, and the punching piston column is slidingly arranged in the telescopic cavity.

[0010] Further, the hydraulic oil circuit comprises a cylinder chamber liquid inlet and a cavity liquid inlet channel, the cylinder chamber liquid inlet is used for supplying liquid to the inner cavity of the cylinder sleeve, and the cavity liquid inlet channel is configured to be communicated with the telescopic cavity only after the pressing piston column is extended and drives the stripping column to press the workpiece tightly, so as to supply oil to the telescopic cavity and drive the punching piston column and the punch to perform punching.

[0011] Further, the cavity liquid inlet channel comprises an outer tube fixed to the inner top of the cylinder sleeve and a sliding column fixedly connected with the top end of the pressing piston column, a liquid hole is axially formed in the sliding column and communicated with the telescopic cavity, and a communication hole is formed in the bottom of the wall of the outer tube; when the pressing piston column drives the stripping column to press the workpiece tightly, the sliding column moves downward, so that the radial hole in the side wall of the sliding column is aligned with the communication hole.

[0012] Further, the hole diameter of the cylinder chamber liquid inlet is greater than the hole diameter of the liquid hole, and the hole diameter of the cylinder chamber liquid outlet of the hydraulic oil circuit is smaller than the hole diameter of the liquid hole in the cylinder chamber liquid outlet, so that when the punching piston column is reset and moves upward, a throttling effect is generated in the process that the oil is discharged from the telescopic cavity into the inner cavity of the cylinder sleeve, a back pressure is formed in the inner cavity of the cylinder sleeve, and the back pressure acts on the pressing piston column to keep the pressing force of the pressing piston column on the workpiece during the exit of the punch.

[0013] Further, the hydraulic oil circuit further comprises a reset liquid inlet channel, the reset liquid inlet channel comprises a first reset liquid inlet used for driving the punching piston column to reset and a second reset liquid inlet used for driving the pressing piston column to reset, and the liquid inlet actions of the first reset liquid inlet and the second reset liquid inlet are sequentially controlled by an electric control valve.

[0014] Further, a pressing plate is further arranged below the stripping column, the pressing plate is movably connected with the stripping column through a limiting rod, and a spring providing elastic support is arranged between the pressing plate and the stripping column.

[0015] Further, the pressing piston column and the punching piston column stroke position are detected by a position sensor.

[0016] Further, the mounting seat is provided with a material discharge groove below the blanking hole, and an inclined guide plate is arranged in the material discharge groove.

[0017] Further, the bottom end of the punching piston column is connected with the punch through a fixing plate, and the material ejection column is sleeved outside the punch and is in clearance fit with the fixing plate and the punch.

[0018] The present application has the following advantages:

[0019] (1) The present application realizes the separation of pressing and punching actions through the collaborative setting of the double-section hydraulic cylinder and the sequential control oil circuit. Before punching, the material ejection column first presses the workpiece and provides continuous and stable hydraulic downward pressure, effectively inhibiting the local flow and bending of the plate; during the punch retreat stage, the back pressure generated by adjusting the oil circuit aperture ratio maintains or even enhances the pressing force, fundamentally overcoming the problem of convexity of the hole material caused by increased friction due to punch wear, and improving the flatness of the bolt fixing hole and the overall punching quality.

[0020] (2) The present application realizes the full-process automation of "pressing-punching-punch retreat-releasing pressing" through real-time monitoring of the piston column position by the proximity switch and switching the oil circuit action by the electric control valve in parallel, thereby reducing the dependence on the skills of the operator and avoiding the downward pressure attenuation caused by fatigue of the traditional spring pressing, and being suitable for large-scale and high-quality production requirements of aluminum mold K plate. BRIEF DESCRIPTION OF DRAWINGS

[0021] Figure 1 It is a schematic diagram of the overall structure of the present application;

[0022] Figure 2 It is a schematic diagram of the hydraulic punching mechanism structure of the present application;

[0023] Figure 3 It is a schematic diagram of the internal structure of the hydraulic cylinder of the present application;

[0024] Figure 4 It is a schematic diagram of the A local enlarged structure of the present application; Figure 3

[0025] Figure 5 It is a schematic diagram of the partial section structure of the hydraulic cylinder of the present application;

[0026] Figure 6 It is a schematic diagram of the C local enlarged structure of the present application; Figure 5

[0027] It is a schematic diagram of the C local enlarged structure of the present application; Figure 7 Figure 3 ​​A magnified schematic diagram of the structure at point B.

[0028] In the diagram: 1. Workbench; 2. Hydraulic punching mechanism; 3. Hydraulic motor assembly; 4. Sheet metal; 5. Die hole; 6. Discharge chute; 7. Guide plate; 8. Stripper column; 9. Telescopic cavity; 10. Flange; 11. Connecting rod; 12. Position sensor; 13. Pressure plate; 14. Limiting rod; 15. Spring; 16. Electrically controlled valve; 101. Table; 102. Support bracket; 201. Mounting base; 202. Hydraulic cylinder; 203. K-plate die; 231. Lower die base; 23 2. Upper die; 2321. Punch; 2322. Fixing plate; 221. Cylinder liner; 222. Pressing piston; 223. Blanking piston; 224. Hydraulic circuit; 2241. Cylinder chamber inlet; 2242. Cavity inlet channel; 2243. Reset inlet channel; 2244. Cylinder chamber outlet; 2421. Outer tube; 2422. Sliding column; 2423. Liquid hole; 2424. Connecting hole; 2431. First reset inlet; 2432. Second reset inlet. Detailed Implementation

[0029] The embodiments of the present invention are described in detail below. These embodiments are implemented based on the technical solution of the present invention, and provide detailed implementation methods and specific operation processes. However, the scope of protection of the present invention is not limited to the following embodiments. In the description of the present invention, words such as "front", "rear", "left", and "right" that indicate orientation or positional relationship are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on the present invention.

[0030] This embodiment discloses a hydraulically driven punching device for aluminum mold K plates, such as... Figures 1-7 As shown, it mainly consists of a workbench 1, a hydraulic punching mechanism 2 mounted on top of the workbench 1, and a hydraulic motor assembly 3 located behind the workbench 1. During the punching operation, the operator places the aluminum mold K plate workpiece at the punching station, and after starting the hydraulic motor assembly 3, the hydraulic punching mechanism 2 can complete the punching operation under hydraulic drive.

[0031] Specifically, such as Figure 1 As shown, the workbench 1 includes a tabletop 101 and a support bracket 102 below it. The bracket consists of four vertical support legs and reinforcing connecting rods between them. The overall structure is stable and can ensure that the tabletop is at a suitable operating height, facilitating processing by the operator. The hydraulic motor assembly 3 is located at the rear of the workbench 1 and is fixedly installed via an independent base frame. It provides a stable power source for the hydraulic punching mechanism 2.

[0032] like Figure 1 andFigure 2 As shown, the hydraulic punching mechanism 2 consists of a mounting base 201, a hydraulic cylinder 202, and a K-plate punching die 203. The mounting base 201 is fixed above the worktable 101, with its front end serving as the punching station. The main body is composed of two parallel plates 4. The hydraulic cylinder 202 is installed above the punching station, and the K-plate punching die 203 is installed below it. This die includes a lower die base 231 and an upper die 232. The lower die base 231 is detachably mounted to the punching position of the mounting base 201 by bolts. It has a concave die hole 5 inside, which penetrates the upper and lower end faces of the lower die base 231. Its lower part has a gradually expanding discharge hole structure, which facilitates the smooth falling of waste material. The mounting base 201 has a discharge groove 6 below the discharge hole. This groove utilizes the natural gap between the two parallel plates 4 and has an inclined guide plate 7 inside, which facilitates the waste material to slide down along the guide plate 7 into the waste frame placed in front of the worktable 1.

[0033] like Figure 3 and Figure 4 As shown, the upper die 232 consists of a fixed plate 2322 and a punch 2321. The fixed plate 2322 is fixedly connected to the piston end of the hydraulic cylinder 202, and the punch 2321 is mounted on the fixed plate 2322, maintaining a precise punching clearance fit with the die hole 5 of the lower die base 231. During the punching operation, the aluminum die K plate is placed on the upper surface of the lower die base 231, and the hydraulic cylinder 202 is activated to drive the punch 2321 to press down, working together with the die hole 5 to complete the punching. The resulting scrap is guided through the blanking hole, the discharge groove 6, and the guide plate 7, and finally falls into the scrap box, achieving a continuous and clean punching operation.

[0034] In actual punching operations, the punch 2321 rubs against the inner wall of the formed hole during each pass and retraction after punching. As the equipment continues to run, the cutting edge and sidewalls of the punch 2321 gradually wear down, leading to a significant increase in friction between it and the hole wall. When the wear reaches a certain level, the increased friction during retraction will exert an upward pulling force on the edge of the hole, causing localized upward deformation of the hole edge. This results in unevenness in the bolt fixing hole area, which in turn affects the subsequent tightening effect of the bolts.

[0035] Therefore, to solve the above problems, this embodiment includes a stripper post 8 fitted outside the punch 2321, with its lower end face always lower than the bottom surface of the punch 2321. During the punching process, the stripper post 8 first clamps the workpiece, and then the punch 2321 moves down to complete the punching. After the punching is completed, the punch 2321 retracts first, at which point the stripper post 8 still maintains a clamping state on the workpiece. This effectively prevents the workpiece from moving upward with the punch 2321 due to friction, and also maintains the flatness of the workpiece, thereby significantly reducing the risk of hole deformation.

[0036] In this embodiment, the stripper column 8 and the punch 2321 are movably connected, allowing the punch 2321 to move up and down relative to the stripper column 8. However, if the stripper column 8 is provided with downward pressure by the spring 15 as in the prior art, its effect in suppressing the upward deformation of the punched hole in the product is directly limited by the performance of the spring 15. While a greater spring 15 force results in better workpiece clamping, there are still shortcomings: First, the spring 15 will experience fatigue during long-term repeated compression cycles, causing its pre-pressure to gradually decrease, thus reducing the clamping effect. Second, the force provided by the spring 15 is not constant; its pressure value fluctuates with changes in the compression stroke, making it difficult to maintain a consistent optimal clamping force throughout the stamping process. Furthermore, relying solely on the spring 15 force for flattening is relatively passive and lacks reliability in dealing with severe friction. Therefore, relying entirely on the spring 15 to provide downward pressure has limitations in long-term stability and flattening effect.

[0037] Therefore, this embodiment uses a hydraulic drive to provide downward pressure to the stripper column 8, replacing the traditional spring 15 pressing structure, to ensure that a stable and continuous downward pressure is applied to the workpiece during the punching process, effectively maintaining the flatness of the plate 4, and avoiding the impact on punching quality due to fluctuations or fatigue attenuation of the spring 15 force.

[0038] In specific implementation, such as Figure 3 and Figure 4 As shown, the hydraulic cylinder 202 adopts a two-stage pressing and punching structure, mainly including a cylinder liner 221, a pressing piston column 222, a punching piston column 223, and corresponding hydraulic oil circuits 224. The cylinder liner 221 is fixed on the mounting base 201, and its interior is provided with an axially retractable pressing piston column 222. The piston column has a telescopic cavity 9 inside, and the punching piston column 223 can move axially along the cavity. The hydraulic oil circuit 224 is used to supply oil to the two piston columns in a segmented sequence. During operation, the hydraulic system starts supplying oil, and the pressing piston column 222 extends first, driving the stripping column 8 connected to it to move downward. At this time, although the punch 2321 moves downward synchronously, its lower end face is always higher than the lower end face of the stripping column 8, and the two maintain a preset relative height. After the stripper column 8 presses the workpiece and establishes a stable downward pressure, the oil circuit is switched to supply oil to the telescopic cavity 9 inside the pressure piston column 222, pushing the punching piston column 223 to extend, thereby driving the punch 2321 connected to it to complete the punching.

[0039] During the retraction process, the system controls the punching piston 223 to retract first, causing the punch 2321 to exit the workpiece. Meanwhile, the pressure piston 222 remains pressed down, ensuring the stripper column 8 always presses firmly against the workpiece. Only after the punch 2321 has fully retracted to the preset safe position does the pressure piston 222 begin to retract, causing the stripper column 8 to separate from the workpiece. This sequential action mechanism maintains effective pressure on the workpiece throughout the entire retraction process, thereby suppressing hole edge deformation caused by friction between the punch 2321 and the hole wall.

[0040] Specifically, in the initial state of this embodiment, a flange 10 is fixedly installed on the outer wall of one end of the pressure piston 222 outside the cylinder liner 221. The flange 10 is rigidly connected to the stripper column 8 via multiple connecting rods 11. A fixing plate 2322 is bolted to the bottom end of the punching piston 223. The fixing plate 2322 has a through hole, and the punch 2321 is supported and installed in this through hole with its stepped structure, with the cutting edge of the punch 2321 facing downwards. The stripper column 8 is located below the fixing plate 2322 and is integrally sleeved on the outer periphery of the punch 2321. The through hole of the fixing plate 2322 and the inner hole of the stripper column 8 are both clearance-fitted with the outer wall of the punch 2321, thereby ensuring that the punch 2321 can move smoothly axially relative to the stripper column 8.

[0041] It should be noted that in this embodiment, the piston end of the pressure piston 222 achieves a sliding seal with the inner wall of the cylinder liner 221 through a seal. Simultaneously, a seal is also provided at the opening at one end of the cylinder liner 221, allowing the cylinder body of the pressure piston 222 to form a sliding seal with the opening; hydraulic oil can be supplied through this opening to drive the pressure piston 222 to retract and reset. The piston end of the punching piston 223 maintains a sliding seal with the telescopic cavity 9 inside the pressure piston 222 through a seal. This telescopic cavity 9 penetrates the lower end face of the pressure piston 222 and also has a seal at its port, forming a sealing fit with the cylinder body of the punching piston 223, thus constituting a complete multi-layer sealing system.

[0042] like Figures 3-7As shown, the hydraulic circuit 224 in this embodiment mainly consists of a cylinder chamber inlet 2241, a cavity inlet channel 2242, a reset inlet channel 2243, and a cylinder chamber outlet 2244. The cylinder chamber inlet 2241 is located on the top wall of the cylinder liner 221 and is connected to the hydraulic motor circuit system via an oil pipe. It is used to supply fluid to the inside of the cylinder liner 221, driving the piston end of the pressing piston column 222 to move downward and extend outward. The cavity inlet channel 2242 is used to supply oil to the telescopic cavity 9 inside the pressing piston column 222. It should be noted that the channel is designed with a timing control function; the channel only connects to the telescopic cavity 9 after the pressing piston column 222 extends and the stripping column 8 connected to its bottom end presses the workpiece, thereby pushing the punching piston column 223 to extend and driving the punch 2321 to complete the punching. Furthermore, this sequential action mechanism ensures that the workpiece is fully clamped and positioned by the stripper column 8 before the punching begins, effectively preventing workpiece displacement during the punching process.

[0043] After the blanking operation is completed, the system injects pressurized oil through the reset inlet channel 2243, driving the blanking piston column 223 and the pressing piston column 222 to retract and reset sequentially. The cylinder outlet 2244 is located on the wall of the cylinder liner 221 and communicates with the inner cavity of the cylinder liner 221. During the piston column reset process, it is responsible for discharging the oil in the cylinder liner 221 from the system, thereby completing a complete working cycle.

[0044] Specifically, the cavity liquid inlet channel 2242 in this embodiment mainly consists of an outer tube 2421, a sliding column 2422, a liquid hole 2423, and a connecting hole 2424. The outer tube 2421 is fixedly installed on the top of the inner cavity of the cylinder liner 221 and located directly above the pressure piston column 222, with an open bottom end. The sliding column 2422 is slidably inserted into the outer tube 2421, achieving dynamic sealing through a sealing element, and its bottom end is concentrically fixedly connected to the top end of the pressure piston column 222. The sliding column 2422 and the pressure piston column 222 have interconnected liquid holes 2423 coaxially arranged inside each other along the axial direction. The liquid hole 2423 extends downwards directly to the telescopic cavity 9 inside the pressure piston column 222, and upwards through a radial hole on the side wall of the sliding column 2422 to communicate with the outside. A connecting hole 2424 is provided at the bottom of the outer tube 2421, and its axis is aligned with the radial hole on the sliding column 2422. In the initial state, the two holes are misaligned; when the pressure piston 222 moves down and drives the stripper 8 to press the workpiece, the sliding column 2422 moves down synchronously to align the two holes. At this time, the pressure oil can enter the telescopic cavity 9 through this channel and push the punching piston 223 and punch 2321 down to complete the punching.

[0045] It should be noted that, to further enhance the pressing effect, such as Figures 3-5As shown, a pressure plate 13 is added below the stripper column 8. A through hole coaxial with the inner hole of the stripper column 8 is formed on the plate, and both are clearance-fitted with the punch 2321. The pressure plate 13 is longitudinally movably connected to the stripper column 8 via a limiting rod 14, and is provided with downward elastic support by a spring 15, maintaining a certain distance between it and the stripper column 8. The diameter of the cylinder inlet 2241 is set to be larger than the diameter of the liquid hole 2423 and the radial hole at one end. When the liquid hole 2423 is aligned with the connecting hole 2424, the inner cavity of the cylinder liner 221 maintains a high pressure, pushing the pressure piston column 222 to continue to move slightly downward, compressing the spring 15, so that the pressure plate 13 and the stripper column 8 together apply a continuous and stable clamping force to the workpiece. In addition, the connecting hole 2424 on the outer tube 2421 is designed as an axially elongated strip structure to ensure that the liquid hole 2423 and the connecting hole 2424 remain connected throughout the entire working stroke of the pressure piston 222, thereby providing reliable pressure guarantee throughout the punching process.

[0046] The core improvement of this embodiment lies in controlling the pressure of the hydraulic circuit 224 during the punch 2321 reset phase to ensure that the pressure piston 222 can continuously apply a stable downward pressure to the workpiece. Specifically, the diameter of the cylinder chamber outlet 2244 is set to be smaller than the diameter of the internal liquid hole 2423. When the punching piston 223 retracts and moves upward, the oil in the telescopic cavity 9 is discharged into the inner cavity of the cylinder liner 221 through the liquid hole 2423, while the oil in the inner cavity of the cylinder liner 221 needs to be discharged through the smaller outlet. This difference in diameter creates a throttling effect when the oil flows out, thereby forming and maintaining a certain back pressure in the inner cavity of the cylinder liner 221. This back pressure continuously acts on the pressure piston 222, ensuring that it maintains a clamping force on the workpiece throughout the punch 2321 retraction process. Compared to the traditional solution that relies on the spring 15 for clamping (which weakens when the punch 2321 resets), this embodiment effectively avoids the upward deformation of the punch hole edge caused by insufficient clamping force.

[0047] To further optimize the blanking effect, in other embodiments, the diameter ratio of the liquid hole 2423 to the cylinder chamber outlet 2244 can be set to be greater than the diameter ratio of the cylinder chamber inlet 2241 to the liquid hole 2423. This diameter ratio makes the throttling effect on the oil flowing into the cylinder liner 221 cavity more significant during the shrinkage phase of the punching piston 223, thereby establishing a higher pressure in the cylinder liner 221 cavity. As a result, the blanking piston 222 can obtain an additional enhanced downward pressure during the reset process of the punch 2321, achieving active leveling of the workpiece and further suppressing hole edge deformation.

[0048] It should be noted that, to control the above actions, both the cylinder chamber inlet 2241 and the outlet are managed by electrically controlled valves 16 in this embodiment. During operation, when the pressing piston 222 needs to extend to press material, the cylinder chamber inlet 2241 opens to allow liquid inflow, while the outlet remains closed to establish the required pressure within the cylinder liner 221. After the punching action is completed, the inlet closes; the outlet opens to drain liquid only when the punch 2321 resets. This ensures that the hydraulic power acts on the correct chamber at the correct time, thereby guaranteeing the reliability of the sequential actions and the stability of the pressing force.

[0049] like Figures 3-7 As shown, the reset inlet channel 2243 of this embodiment includes a first reset inlet 2431 and a second reset inlet 2432. The first reset inlet 2431 is located on the tube wall of the pressure piston column 222, communicating with its internal telescopic cavity 9, and is located below the flange 10. When the pressure piston column 222 is in the initial retracted state, the inlet is located outside the cylinder liner 221; after the punching piston column 223 extends to its maximum stroke to complete the punching, the first reset inlet 2431 is located below the piston end of the punching piston column 223. An electrically controlled valve 16 is provided at this port, which, when opened, allows pressurized oil to be introduced, driving the punching piston column 223 to move upward and reset. The second reset inlet 2432 is located on the bottom section of the tube wall of the cylinder liner 221, communicating with the inner cavity of the cylinder liner 221. Its position is configured such that when the pressure piston column 222 extends to its maximum stroke (i.e., the stripper column 8 presses the workpiece), the inlet is located below the piston end of the pressure piston column 222. Both the first and second reset inlets 2432 are connected to the hydraulic motor system via pipelines to control the flow of hydraulic fluid.

[0050] During the reset operation, hydraulic fluid is first introduced through the first reset inlet 2431, pushing the punching piston 223 upwards within the telescopic cavity 9 to reset. Below, the fluid is discharged into the cylinder liner 221 through the fluid hole 2423. Once the punching piston 223 is fully retracted and the punch 2321 has reset to its position, the first reset inlet 2431 stops supplying fluid, and its electronically controlled valve 16 closes. This uses hydraulic pressure to lock the position of the punching piston 223, preventing accidental downward movement. This operation effectively creates a closed cavity composed of incompressible hydraulic oil within the telescopic cavity below the punching piston 223. Due to the incompressible nature of the liquid, this closed oil cavity acts as a rigid solid support, effectively supporting and fixing the punching piston 223 at the reset endpoint. Subsequently, the second reset inlet 2432 begins supplying fluid, pushing the pressure piston 222 upwards to reset. During this process, since the first reset inlet 2431 is closed, the oil inside the cylinder liner 221 can be effectively prevented from flowing back into the telescopic cavity 9 through the liquid hole 2423, thereby eliminating the unexpected downward movement of the punching piston 223. In addition, while the second reset inlet 2432 is being filled, the electrically controlled valve 16 of the cylinder chamber inlet 2241 can be opened simultaneously to increase the cross-sectional area of ​​the drain channel inside the cylinder liner 221 and accelerate the reset speed of the pressing piston 222.

[0051] To achieve automatic control of the punching process, multiple proximity switches are installed as position sensors 12 at corresponding locations in this system. When the punching piston 223 moves down to complete the punching, the proximity switch installed on the top of the stripper column 8 is triggered when it contacts the fixing plate 2322. This signal indicates that the punch 2321 has reached its maximum stroke and the punching action is complete. Immediately, the system closes the cylinder inlet 2241 to stop oil supply and opens the first reset inlet 2431 to supply oil, driving the punching piston 223 to begin resetting. To detect the fully retracted state of the punching piston 223, another proximity switch is installed above its bottom flange face. When this switch contacts the bottom end of the pressure piston 222, it is confirmed that the punching piston 223 has been reset to the correct position. The system then closes the first reset inlet 2431 and simultaneously opens the second reset inlet 2432 to move the pressure piston 222 upward to reset. Furthermore, a proximity switch installed on the top surface of the flange 10 on the outer wall of the pressure piston column 222 is used to monitor its reset endpoint position, thus forming a complete closed-loop control sequence. In other embodiments, a pressure sensor can also be installed inside the cylinder liner 221 to monitor the oil pressure status in real time, and also serve as overload protection for the system.

[0052] In this embodiment, during operation: First, the operator places the aluminum mold K plate workpiece on the punching station of the lower mold base 231 on the workbench 1. After starting the system, the hydraulic motor supplies oil to the inner cavity of the cylinder liner 221 through the inlet at the top of the cylinder liner 221, driving the pressure piston 222 to extend first, causing the stripper 8 at its bottom to move down and press the workpiece. After the stripper 8 presses the workpiece, the system switches the oil circuit, allowing pressurized oil to enter the telescopic cavity 9 inside the pressure piston liner 222 through the connected cavity inlet channel 2242, pushing the punching piston 223 and the punch 2321 downward to complete the punching. At this time, the stripper 8 always remains in a pressed state to prevent the workpiece from shifting.

[0053] After blanking is completed, the system enters the reset phase. Driven by the oil supply from the first reset inlet 2431, the blanking piston 223 moves upwards to reset, and the punch 2321 exits the workpiece. At this time, the pressure piston 222, under the back pressure within the cylinder liner 221 (maintained by the throttling effect generated by the smaller-diameter cylinder outlet 2244), maintains its clamping force on the workpiece, effectively preventing the punch 2321 from bulging and deforming at the hole edge due to friction during exit. Once the blanking piston 223 has fully reset (confirmed by the proximity switch above its flange 10), the first reset inlet 2431 closes. Subsequently, the second reset inlet 2432 opens, supplying oil to the cylinder liner 221, pushing the pressure piston 222 to move the stripper column 8 upwards to reset. During this process, the cylinder outlet 2241 can be opened simultaneously to expand the drainage area and accelerate the reset.

[0054] This enables an automated sequence of actions: "pressing first, then punching; retracting the punch 2321, then releasing the pressure material," ensuring stable and reliable punching quality.

[0055] It will be apparent to those skilled in the art that the present invention is not limited to the details of the exemplary embodiments described above, and that the invention can be implemented in other specific forms without departing from its spirit or essential characteristics. Therefore, the embodiments should be considered in all respects as exemplary and non-limiting, and the scope of the invention is defined by the appended claims rather than the foregoing description. Thus, all variations falling within the meaning and scope of equivalents of the claims are intended to be included within the present invention. No reference numerals in the claims should be construed as limiting the scope of the claims.

Claims

1. A hydraulically driven punching device for aluminum mold K-plate, comprising a worktable (1), a hydraulic punching mechanism (2) disposed above the worktable (1), and a hydraulic motor assembly (3), wherein the hydraulic punching mechanism (2) comprises a mounting base (201), a hydraulic cylinder (202), and a K-plate die (203), wherein the K-plate die (203) comprises a lower die base (231) and a punch (2321) driven by the hydraulic cylinder (202), characterized in that, The punch (2321) is fitted with a stripper column (8) on its outside. The hydraulic cylinder (202) is a two-stage hydraulic cylinder (202), which is equipped with a pressing piston column (222) and a blanking piston column (223) that can move relatively independently. The hydraulic cylinder (202) also includes a cylinder liner (221), which is fixed on the mounting base (201) and has an axially retractable pressure piston column (222) inside. The pressing piston (222) is driven to connect with the stripping piston (8), and the punching piston (223) is driven to connect with the punch (2321); The device is provided with a hydraulic circuit (224), which is configured to control the pressing piston (222) and the punching piston (223) to perform sequential actions, so that during punching, the stripper (8) first presses the workpiece, and then the punch (2321) performs punching. The pressure piston (222) has a telescopic cavity (9) inside, and the punching piston (223) is slidably disposed in the telescopic cavity (9); the hydraulic circuit (224) includes a cylinder chamber inlet (2241) and a cavity inlet channel (2242). The cylinder chamber inlet (2241) is used to supply liquid to the inner cavity of the cylinder liner (221). The cavity inlet channel (2242) is configured to communicate with the telescopic cavity (9) only after the pressure piston (222) extends and drives the stripper (8) to press the workpiece, so as to supply oil to the telescopic cavity (9) and drive the punching piston (223) and punch (2321) to perform punching; The cavity liquid inlet channel (2242) includes an outer tube (2421) fixed to the top of the cylinder liner (221) and a sliding column (2422) fixedly connected to the top of the pressure piston column (222). The sliding column (2422) has an axial liquid hole (2423) inside that communicates with the telescopic cavity (9). The bottom of the outer tube (2421) has a connecting hole (2424). When the pressure piston column (222) drives the stripper column (8) to press the workpiece, the sliding column (2422) moves down so that the radial hole on its side wall aligns with the connecting hole (2424). The diameter of the cylinder inlet (2241) is larger than the diameter of the liquid hole (2423), and the diameter of the cylinder outlet (2244) of the hydraulic oil circuit (224) is smaller than the diameter of its internal liquid hole (2423). This is so that when the punching piston (223) is reset and moved upward, the oil is discharged from the telescopic cavity (9) into the inner cavity of the cylinder liner (221) and a throttling effect is generated, forming a back pressure in the inner cavity of the cylinder liner (221). This back pressure acts on the pressing piston (222) so that it maintains the clamping force on the workpiece during the punch (2321) withdrawal stage.

2. The hydraulically driven punching device for aluminum mold K-plate as described in claim 1, characterized in that, The hydraulic circuit (224) further includes a reset inlet channel (2243), which includes a first reset inlet (2431) for driving the punching piston (223) to reset and a second reset inlet (2432) for driving the pressing piston (222) to reset. The inlet action of the first reset inlet (2431) and the second reset inlet (2432) is sequentially controlled by an electronic control valve (16).

3. The hydraulically driven punching device for aluminum mold K-plate as described in claim 1, characterized in that, A pressure plate (13) is also provided below the stripping column (8). The pressure plate (13) is movably connected to the stripping column (8) through a limiting rod (14), and a spring (15) is provided between the pressure plate (13) and the stripping column (8) to provide elastic support.

4. The hydraulically driven punching device for aluminum mold K-plate as described in claim 1, characterized in that, The stroke positions of the pressing piston (222) and the punching piston (223) are detected by the position sensor (12).

5. The hydraulically driven punching device for aluminum mold K-plate as described in claim 1, characterized in that, The mounting base (201) is provided with a discharge groove (6) below the discharge hole, and an inclined guide plate (7) is provided in the discharge groove (6).

6. The hydraulically driven punching device for aluminum mold K-plate as described in claim 1, characterized in that, The bottom end of the punching piston column (223) is connected to the punch (2321) through the fixing plate (2322). The stripping column (8) is sleeved on the outside of the punch (2321) and is clearance-fitted with both the fixing plate (2322) and the punch (2321).

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