Clamping and lifting device for moving the table of a punch press, hydraulic system and control method

Abstract

The application discloses a clamping and jacking device, a hydraulic system and a control method for a punch moving workbench, and relates to the technical field of stamping equipment. The device comprises a workbench, a moving table, a jacking module, a clamping module and a linkage module. The moving table is provided with walking wheels at the bottom. The workbench is provided with guide rails with positioning ports. The jacking oil cylinder of the jacking module drives the lifting plate to rise to the top surface of the guide rails to block the positioning ports and form a continuous track. The clamping oil cylinder of the clamping module drives the clamping plate to clamp the moving table in cooperation with the pressing edge. The hydraulic system is integrated in a valve block and comprises an electromagnetic reversing valve and a hydraulic control check valve. The valve block is provided with a branch oil channel that is connected with the jacking control oil channel and the control oil port of the hydraulic control check valve, thereby realizing linkage control of automatic release of clamping during jacking. The application also discloses a control method of the device. The application has the functions of jacking and clamping, is compact in structure, reliable in action, and effectively improves the stability of the moving table during moving in and moving out, and the positioning accuracy and safety of stamping operation.

Description

Technical Field

[0001] This invention relates to the field of stamping equipment technology, and more specifically, to a clamping and lifting device, hydraulic system, and control method for a moving worktable of a punch press. Background Technology

[0002] In the field of stamping, the movable worktable, as an important auxiliary equipment for punch presses, is widely used in large-scale stamping production lines. After the mold installation and workpiece loading and unloading are completed outside the punch press, the movable worktable moves along the guide rail into the working area of ​​the punch press to perform stamping operations. Its application significantly shortens the auxiliary time for mold changing and workpiece loading and unloading, effectively improving the overall efficiency of the stamping production line.

[0003] In existing technologies, the precise positioning and reliable clamping of the moving worktable on the punch press worktable are crucial for ensuring the accuracy and safety of stamping processes. Currently, the positioning method for the moving worktable typically involves the traveling wheels falling into pre-set positioning slots on the guide rails to achieve initial positioning, while clamping mechanisms located around the worktable apply clamping force to prevent displacement of the moving worktable during the stamping process.

[0004] However, existing technologies still have many shortcomings. First, when the moving platform moves into or out of the worktable, the traveling wheels need to cross the positioning openings on the guide rails. If the positioning openings are not effectively blocked, the traveling wheels will experience severe vibrations and impacts when passing through, which not only affects the stability of the moving platform's movement but also easily leads to premature wear of the traveling wheels and guide rails, shortening the equipment's service life. Second, the clamping circuit and lifting circuit often use two independent hydraulic pump sources or are controlled by components such as sequence valves and accumulators. This not only results in a large number of system components, complex piping, and a large space occupation, but also requires the hydraulic pumps to run continuously under pressure-holding conditions, causing energy waste and oil overheating. Third, for clamping cylinders that use spring reset, in order to ensure smooth oil return from the rod chamber when releasing the clamp, a separate control pressure is usually required to open the hydraulic check valve. Sometimes, an additional control oil source or an increase in the number of directional valve stages is required, which further increases the complexity of the system and manufacturing costs.

[0005] Therefore, a new solution is needed to address this problem. Summary of the Invention

[0006] To solve the above-mentioned technical problems, the present invention provides a clamping and lifting device, a hydraulic system and a control method for a moving worktable of a punch press.

[0007] The technical solution of this invention is: A clamping and lifting device for a moving worktable of a punch press, characterized in that: it includes a worktable mounted on the punch press body and a movable stage that can be moved onto the worktable; the bottom of the movable stage is provided with a plurality of traveling wheels arranged in a rectangular array; a guide rail that cooperates with the traveling wheels is fixedly connected to the worktable; the guide rail has positioning holes corresponding one-to-one with the plurality of traveling wheels; a plurality of clamping modules for clamping the movable stage are provided on the worktable; and a lifting module for lifting the movable stage to disengage the traveling wheels from the positioning holes is provided at the bottom of the worktable; it also includes a linkage module for driving the clamping modules and the lifting module, the linkage module including a power source module and a control logic module; the lifting module includes a vertical... The clamping module includes several lifting cylinders vertically installed at the bottom of the worktable and located on one side of the guide rail. The input end of the power source module is connected to the oil tank. The control logic module includes an electromagnetic reversing valve and a hydraulic check valve. The output end of the power source module is connected to the input end of the electromagnetic reversing valve. The return end of the electromagnetic reversing valve is also connected to the oil tank. The electromagnetic reversing valve has two output ends. One output end is connected to several clamping cylinders through the hydraulic check valve. The other output end is connected to the lifting cylinder and is connected in parallel with the control port of the hydraulic check valve, so as to forcibly open the hydraulic check valve when oil is introduced into the lifting cylinder, so as to unload oil from the clamping cylinder.

[0008] The invention is further configured such that the number of lifting cylinders corresponds to the number of traveling wheels, and a lifting plate is fixedly connected to the drive end of the lifting cylinder, with the top of the lifting plate contacting the outer peripheral wall of the traveling wheel; when the drive end of the lifting cylinder moves to the maximum stroke position, the lifting plate rises to the top and its top surface is flush with the top surface of the guide rail, forming a continuous track and sealing the positioning port.

[0009] The invention is further configured such that the lifting cylinder is vertically arranged and the hydraulic oil is connected to the rodless chamber of the lifting cylinder. When there is no pressure oil in the lifting cylinder, the driving end of the lifting cylinder is reset by its own gravity, which drives the lifting plate to descend and makes the positioning port fully open.

[0010] The invention is further configured such that the piston rod end of the clamping cylinder passes through the worktable and is fixedly connected to a clamping plate, and a through groove is provided on the moving table for the clamping plate and the piston rod of the clamping cylinder to pass through, and pressing edges that cooperate with the clamping plate are symmetrically arranged on the inner side wall of the through groove.

[0011] The invention is further configured such that the bottom surface of the pressing edge is flush with the bottom surface of the moving stage, and the piston rod of the clamping cylinder drives the clamping plate to press down and abut against the pressing edge, thereby applying a downward clamping force to the moving stage.

[0012] The present invention is further configured such that a compression spring is provided in the rodless chamber of the clamping cylinder. When oil enters the rod chamber of the clamping cylinder and the piston rod retracts, the piston rod applies an external force to the compression spring, causing it to compress and deform. When oil is discharged from the rod chamber of the clamping cylinder, the compression spring resets, pushes the piston rod to extend, and drives the clamping plate away from the pressing edge.

[0013] The invention is further configured such that the control logic module is integrated onto a valve block, the valve block having an oil outlet for the clamping cylinder and an oil outlet for the lifting cylinder on its side, and the valve block having an oil inlet passage, an oil return passage, a clamping cylinder control passage, and a lifting cylinder control passage inside; the output end of the power source module is connected to the oil inlet passage of the valve block, the oil return passage of the valve block is connected to the oil tank via a pipeline, the oil return end of the electromagnetic directional valve is connected to the oil return passage, the input end of the electromagnetic directional valve is connected to the oil inlet passage, and one of the output ends of the electromagnetic directional valve is connected to the clamping cylinder control passage via a hydraulic check valve. The oil passage is connected at one end and at the other end to the control oil passage of the lifting cylinder; a branch oil passage is also provided in the valve block, one end of which is connected to the control oil passage of the lifting cylinder and the other end is connected to the control oil port of the hydraulic check valve, so as to force the hydraulic check valve to open when oil enters the control oil passage of the lifting cylinder. The oil outlet of the clamping cylinder is connected to the control oil passage of the clamping cylinder, and the oil outlet of the lifting cylinder is connected to the control oil passage of the lifting cylinder. The oil outlet of the clamping cylinder is connected to the rod chamber of each clamping cylinder through a pipeline, and the oil outlet of the lifting cylinder is connected to the rodless chamber of each lifting cylinder through a pipeline.

[0014] The present invention is further configured such that the electromagnetic directional valve is a two-position four-way electromagnetic directional valve, wherein its P port is connected to the oil inlet channel, its T port is connected to the oil return channel, its A port is connected to the oil inlet of the hydraulic control check valve, and its B port is connected to the control oil channel of the lifting cylinder.

[0015] The present invention is further configured such that the power source module includes a motor, a pressure-compensated variable pump and a first check valve, the output shaft of the motor is driven to be connected to the input shaft of the pressure-compensated variable pump, the oil inlet of the pressure-compensated variable pump is used to be submerged below the oil level in the oil tank, its oil outlet is connected to the inlet of the first check valve through a pipeline, and the outlet of the first check valve is connected to the oil inlet of the valve block.

[0016] The present invention is further configured such that the control logic module includes a pressure relay, which is mounted on the valve block and has two detection ports, which are respectively connected to the clamping cylinder control oil passage and the lifting cylinder control oil passage, so as to detect the clamping pressure and the lifting pressure and convert the pressure signal into an electrical signal.

[0017] The present invention is further configured such that a main pipe is connected between the valve block and several clamping cylinders, and a tee is connected to the main pipe. One end of the tee is connected to each clamping cylinder through various pipes, and the other end is connected to a maintenance solenoid valve. The end of the maintenance solenoid valve away from the tee is connected to the oil tank.

[0018] The technical solution of this invention is still: A control method for a clamping and lifting device for a moving worktable of a punch press, the device comprising a worktable, a movable stage movably disposed on the worktable, a lifting module for lifting the movable stage, a clamping module for clamping the movable stage, and a linkage module for driving the clamping module and the lifting module, the clamping module comprising a clamping cylinder with a compression spring, characterized by comprising the following steps: S1: Drive the lifting module through the linkage module to make the lifting module rise and block the positioning port to form a continuous track, and move the moving platform into the worktable. S2: Control the linkage module to reset the lifting module, and the moving platform descends to make the walking wheels fall into the positioning port, thereby realizing the initial positioning of the moving platform on the worktable; S3: The clamping module is driven by the linkage module to apply clamping force to the moving table, thereby fixing the moving table to the worktable for stamping operation; S4: After stamping is completed, the lifting action and clamping release action are performed synchronously through the linkage module. That is, the linkage module drives the lifting module to lift the moving platform, and at the same time, the linkage module controls the clamping module to release the clamping of the moving platform. S5: Move the mobile stage off the worktable.

[0019] The present invention is further configured such that, in step S4, the linkage module supplies oil to the rodless chamber of the lifting cylinder to drive the lifting module to lift the moving platform, and at the same time supplies oil to the control port of the hydraulic check valve through the branch oil passage opened in the valve block, forcibly opening the hydraulic check valve, so that the rod chamber of the clamping cylinder is connected to the oil tank through the return oil end of the hydraulic check valve and the solenoid reversing valve, and the piston rod of the clamping cylinder is reset under the action of the compression spring in the rodless chamber, driving the clamping plate away from the pressing edge, and releasing the clamping of the moving platform.

[0020] The beneficial technical effects of this invention are: The lifting plate is raised to be flush with the top surface of the guide rail by the lifting cylinder, which completely blocks the positioning port to form a continuous track. The traveling wheels can pass smoothly through the original positioning port position via the lifting plate, which effectively avoids the vibration and impact generated when the traveling wheels cross the positioning port, reduces the wear between the traveling wheels and the guide rail, and extends the service life of the equipment.

[0021] By integrating the solenoid directional valve, the hydraulic check valve, and the internal oil passage into a single valve block, the sequential linkage control of clamping and lifting actions is achieved through only one two-position four-way solenoid directional valve in conjunction with the hydraulic check valve and the built-in branch oil passage. This significantly reduces the number of pipeline connections and independent components, resulting in a more compact system structure and lower cost.

[0022] By directly controlling the hydraulic check valve through the branch oil passage led from the lifting cylinder control oil passage, the clamping cylinder can be automatically and reliably released at the same time as the lifting action is initiated. This achieves mechanical-hydraulic linkage interlock between clamping and lifting, avoiding misoperation and ensuring high safety and reliability.

[0023] The lifting module adopts a design where the hydraulic cylinder drives the module to reset by its own gravity, and the clamping module uses a compression spring inside the rodless cavity to achieve reset. Neither of them requires an external reset power source, resulting in a simple and reliable structure that significantly reduces manufacturing and maintenance costs.

[0024] The motor is started and stopped by a pressure-compensated variable pump and a pressure relay. The motor stops running when the pressure is maintained, which realizes on-demand oil supply and energy-saving operation, and effectively avoids oil heating and energy waste. Attached Figure Description

[0025] Figure 1 This is a schematic diagram of the structure of the present invention; Figure 2 yes Figure 1 Enlarged view of point A in the middle; Figure 3 This is a schematic diagram of the structure of the concealed mobile platform under broken rail conditions according to the present invention; Figure 4 yes Figure 3 Enlarged view at point B in the middle; Figure 5 This is a schematic diagram of the structure of the hidden mobile platform in the rail-connected state of the present invention; Figure 6 yes Figure 5 Enlarged view of point C in the middle; Figure 7 This is a hydraulic schematic diagram of the present invention; Figure 8 This is a schematic diagram of the valve block of the present invention.

[0026] In the diagram, 1. Workbench; 11. Guide rail; 111. Positioning port; 12. Extension rail; 2. Moving table; 21. Traveling wheel; 22. Clamping edge; 3. Lifting cylinder; 31. Lifting plate; 4. Clamping cylinder; 41. Clamping plate; 5. Motor; 6. Pressure-compensated variable pump; 7. First check valve; 8. Valve block; 81. Solenoid directional valve; 82. Hydraulic check valve; 83. Pressure relay; 9. Pressure gauge switch; 91. Pressure gauge; 100. Maintenance solenoid valve. Detailed Implementation

[0027] In order to better understand the technical means of the present invention and to implement it in accordance with the contents of the specification, the specific embodiments of the present invention will be described in further detail below with reference to specific examples. The following examples are used to illustrate the present invention, but are not intended to limit the scope of the present invention.

[0028] A clamping and lifting device for a moving worktable of a punch press, such as Figures 1-6 As shown, the press includes a worktable 1 fixedly mounted on the press body and a movable stage 2 movably mounted on the worktable 1. The worktable 1 is the fixed working platform of the press, and its upper surface is flat. The movable stage 2 is a trolley structure that can move along the worktable 1 and is used to carry molds or workpieces. The bottom of the movable stage 2 is provided with several traveling wheels 21 arranged in a rectangular array. The traveling wheels 21 are used to cooperate with the guide rails 11 on the worktable 1 to realize the rolling movement of the movable stage 2 on the worktable 1. The guide rails 11 that cooperate with the traveling wheels 21 are fixedly connected to the worktable 1, and the guide rails 11 extend along the moving direction of the movable stage 2. The guide rails 11 have positioning holes 111 that correspond one-to-one with the traveling wheels 21. The shape and size of the positioning holes 111 are adapted to the outer contour of the traveling wheels 21. When the traveling wheel 21 moves to the position of the positioning hole 111, the traveling wheel 21 falls into the positioning hole 111, realizing the initial positioning of the movable stage 2 on the worktable 1. At this time, the bottom surface of the moving table 2 can fit against the top surface of the worktable 1, ensuring that the moving table 2 is in the correct stamping working position.

[0029] The worktable 1 is provided with several clamping modules for clamping the moving stage 2, and a lifting module for raising the moving stage 2 is provided at the bottom of the worktable 1. An extension rail 12 that communicates and cooperates with the guide rail 11 is also fixedly connected to one side of the worktable 1. The extension rail 12 extends the movable distance of the moving stage 2, making it more convenient to move the moving stage 2 in and out.

[0030] The lifting module includes several lifting cylinders 3 disposed at the bottom of the worktable 1. The number of lifting cylinders 3 corresponds to the number of traveling wheels 21. In this embodiment, there are four traveling wheels 21, and correspondingly, there are also four lifting cylinders 3, which are respectively disposed directly below the four traveling wheels 21. Each lifting cylinder 3 is vertically arranged, and its cylinder body is fixedly installed at the bottom of the worktable 1. Its drive end extends out of the worktable 1 and is located at the positioning port 111 of the guide rail 11.

[0031] A lifting plate 31 is fixedly connected to the drive end of each lifting cylinder 3, and the top of the lifting plate 31 contacts the outer peripheral wall of the traveling wheel 21. The shape and size of the lifting plate 31 are adapted to the positioning port 111. When the drive end of the lifting cylinder 3 is in the retracted state, the lifting plate 31 is located inside the positioning port 111 and its top surface is lower than the top surface of the guide rail 11. At this time, the positioning port 111 is open, and the traveling wheel 21 can fall into the positioning port 111. When the drive end of the lifting cylinder 3 extends and moves to the maximum stroke position, the lifting plate 31 is pushed to the top. At this time, the top surface of the lifting plate 31 is flush with the top surface of the guide rail 11. The lifting plate 31 completely blocks the positioning port 111, forming a track surface continuous with the guide rail 11. The traveling wheel 21 can smoothly pass through the original position of the positioning port 111 via the lifting plate 31 without vibration or impact.

[0032] The lifting cylinder 3 is set vertically, and the hydraulic oil is connected to the rodless chamber of the lifting cylinder 3. When there is no pressure oil in the rodless chamber of the lifting cylinder 3, the driving end of the lifting cylinder 3 naturally resets downward under its own weight and the weight of the moving platform 2, driving the lifting plate 31 to descend, so that the positioning port 111 is fully opened, and the traveling wheel 21 can fall back into the positioning port 111. The clamping module includes several clamping cylinders 4 disposed at the bottom of the worktable 1 and located on one side of the guide rail 11. In this embodiment, four clamping cylinders 4 are arranged in a rectangular array, located at the four corners of the moving platform 2. Each clamping cylinder 4 is vertically mounted, its cylinder body fixedly installed at the bottom of the worktable 1, and its piston rod (i.e., the end of the piston rod) extends upward from the worktable 1 and is fixedly connected to a clamping plate 41. The clamping plate 41 is a horizontally arranged plate-shaped component with an area larger than the cross-sectional area of ​​the piston rod of the clamping cylinder 4, used to cooperate with the pressing edge 22 on the moving platform 2 to apply clamping force.

[0033] The movable table 2 has a through groove through which the clamping plate 41 and the piston rod of the clamping cylinder 4 pass. The through groove extends vertically through the movable table 2. Symmetrically arranged on the inner wall of the through groove are clamping edges 22 that cooperate with the clamping plate 41. The clamping edges 22 are flange structures protruding inward from the inner wall of the through groove. The bottom surface of the clamping edges 22 is flush with the bottom surface of the movable table 2. When the movable table 2 moves into position and the traveling wheel 21 is inserted into the positioning opening 111, the clamping cylinder 4 is driven to retract its piston rod. The clamping plate 41 moves downward and abuts against the top surface of the clamping edges 22, thereby applying downward pressure to the entire movable table 2, tightly clamping the movable table 2 onto the worktable 1, preventing displacement of the movable table 2 during the stamping process.

[0034] A compression spring is installed in the rodless chamber of the clamping cylinder 4, with one end abutting against the bottom wall of the cylinder body and the other end abutting against the piston rod surface. Hydraulic oil is connected to the rod chamber of the clamping cylinder 4. When oil enters the rod chamber of the clamping cylinder 4, the piston rod moves downward, causing the clamping plate 41 to press down. At the same time, the piston applies an external force to the compression spring, causing it to compress and deform. When oil is discharged from the rod chamber of the clamping cylinder 4, the compression spring resets under its own elastic force, pushing the piston rod upward and causing the clamping plate 41 to move away from the pressing edge 22, releasing the clamping of the moving platform 2. At this time, the moving platform 2 can move freely. The clamping cylinder 4 adopts a single-acting cylinder combined with spring reset, which can achieve automatic reset without an additional power source, and the structure is simple and reliable.

[0035] A hydraulic system for a clamping and lifting device for a moving worktable in a punch press, such as Figure 7 and Figure 8 As shown, it includes a linkage module for driving the clamping module and the lifting module. The linkage module includes a power source module and a control logic module. The linkage module provides hydraulic power to the lifting cylinder 3 and the clamping cylinder 4, and realizes the sequential control and interlocking of clamping and lifting actions. The power source module includes a motor 5, a pressure-compensated variable pump 6, and a first check valve 7. The output shaft of the motor 5 is coaxially connected to the input shaft of the pressure-compensated variable pump 6 via a coupling, and the motor 5 drives the pressure-compensated variable pump 6. The oil inlet of the pressure-compensated variable pump 6 is submerged below the liquid level in the oil tank, and its outlet is connected to the inlet of the first check valve 7 via a pipeline. The pressure-compensated variable pump 6 is a variable pump, and its output flow rate can be automatically adjusted according to the system pressure. Under pressure-holding conditions, it can achieve zero flow output, effectively reducing energy consumption and oil heating. The outlet of the first check valve 7 serves as the system's high-pressure oil output terminal and is connected to the oil inlet of the control logic module. The first check valve 7 is used to prevent the system's high-pressure oil from flowing backward and to maintain the system pressure.

[0036] The control logic module includes a solenoid directional valve 81, a hydraulic check valve 82, a pressure relay 83, a pressure gauge switch 9, and a pressure gauge 91. This control logic module forms a closed-loop control with the lifting cylinder 3 and the clamping cylinder 4 through the internal flow channel of a valve block 8. The solenoid directional valve 81 is mounted on the top of the valve block 8. Valve block 8 is a rectangular metal component with independent oil inlet, oil return, clamping cylinder control, and lifting cylinder control oil passages machined internally. The side wall of valve block 8 has an oil inlet and an oil return port; the oil inlet connects to the oil inlet passage, and the oil return port connects to the oil return passage. The outlet of the first check valve 7 is connected to the oil inlet of valve block 8 via a pipeline, and the oil return port of valve block 8 is connected to the oil tank via a pipeline.

[0037] The solenoid directional valve 81 is a two-position four-way solenoid directional valve, installed on the top surface of the valve block 8. The P port of the solenoid directional valve 81 is connected to the oil inlet passage, the T port is connected to the oil return passage, the A port is connected to the oil inlet of the hydraulic check valve 82, and the B port is connected to the control oil passage of the lifting cylinder. The solenoid directional valve 81 is a two-position four-way valve with two working positions: the first working position is with the P port connected to the A port and the B port connected to the T port; the second working position is with the P port connected to the B port and the A port connected to the T port.

[0038] A hydraulically controlled check valve 82 is located on top of the valve block 8. Its inlet is connected to port A of the solenoid directional valve 81, and its outlet is connected to the clamping cylinder control oil passage. The hydraulically controlled check valve 82 allows oil to flow unidirectionally from the inlet to the outlet, and is cut off in the opposite direction unless its control port receives a control pressure signal. The control port of the hydraulically controlled check valve 82 is connected to the lifting cylinder control oil passage through a branch oil passage opened in the valve block 8. One end of this branch oil passage is connected to the lifting cylinder control oil passage, and the other end is connected to the control port of the hydraulically controlled check valve 82. When oil enters the lifting cylinder control oil passage, the pressure oil is used to forcibly open the hydraulically controlled check valve 82, so that the clamping cylinder control oil passage is connected to port A of the solenoid directional valve 81, thereby realizing the pressure relief and oil return of the clamping cylinder 4. This design cleverly utilizes the pressure oil of the lifting action to simultaneously control the opening of the hydraulic check valve 82, achieving interlocking between clamping and lifting—when the lifting action is performed, the clamping cylinder 4 automatically releases the clamp.

[0039] The valve block 8 has a clamping cylinder oil outlet and a lifting cylinder oil outlet on its side. The clamping cylinder oil outlet is connected to the clamping cylinder control oil passage, and the lifting cylinder oil outlet is also connected to the lifting cylinder control oil passage. The clamping cylinder oil outlet is connected to the rod chamber of each clamping cylinder 4 through a pipeline, and the lifting cylinder oil outlet is connected to the rodless chamber of each lifting cylinder 3 through a pipeline.

[0040] Pressure relay 83 is also located on top of valve block 8. Pressure relay 83 is a W-type superimposed pressure relay with two detection ports at its bottom, connected to the clamping cylinder control oil passage and the lifting cylinder control oil passage respectively. These ports are used to detect clamping pressure and lifting pressure and convert the hydraulic pressure signal into an electrical signal. The signal output terminal of pressure relay 83 is electrically connected to the PLC controller, and motor 5 is also electrically connected to the PLC controller. When the pressure in the clamping chamber or lifting chamber reaches the set value, pressure relay 83 sends an electrical signal to the PLC controller. The PLC controller then controls the start and stop of motor 5 according to preset logic, achieving automated and energy-saving operation of the system.

[0041] A pressure gauge switch 9 is connected to the pipeline between the outlet of the first check valve 7 and the oil inlet of the valve block 8. A pressure gauge 91 is installed on the pressure gauge switch 9. The pressure gauge 91 is used to display the system pressure, which facilitates the operator to monitor the system's operating status in real time. By starting and stopping the pressure gauge switch 9, the pressure gauge 91 can be safely replaced while the system is pressurized, improving the system's maintainability.

[0042] A solenoid valve base plate is also installed on the punch press body. A maintenance solenoid valve 100 is fixedly connected to the solenoid valve base plate, and one end of the maintenance solenoid valve 100 is connected to the oil tank. The oil outlet of the clamping cylinder is connected to a main pipe, and a tee is connected to the main pipe. One end of the other two ends of the tee is connected to each clamping cylinder 4 through various pipelines, and the other end is connected to the end of the maintenance solenoid valve 100 away from the oil tank. The maintenance solenoid valve 100 is used to release the residual pressure in the rod chamber of the clamping cylinder 4 during system maintenance to ensure maintenance safety.

[0043] A control method for a clamping and lifting device for a moving worktable in a punch press includes, S1: Initially, motor 5 is not started, and electromagnetic reversing valve 81 is in the first working position (P port is connected to A port, and B port is connected to T port). There is no pressurized oil in the rodless chamber of lifting cylinder 3, and its drive end is in a retracted state under its own weight and the weight of moving platform 2. Lifting plate 31 is in a low position, and positioning port 111 is fully open. There is no pressurized oil in the rod chamber of clamping cylinder 4, and the compression spring in its rodless chamber is in a reset state. Clamping plate 41 is in a high position, away from clamping edge 22. Moving platform 2 is not clamped and is in a freely movable state. When the moving platform 2 needs to be moved into the worktable 1 from the outside, the control solenoid directional valve 81 switches to the second working state (P port connected to B port, A port connected to T port). The PLC controller controls the motor 5 to start, and the motor 5 drives the pressure-compensated variable pump 6 to operate. The pressure-compensated variable pump 6 draws oil from the oil tank and converts it into high-pressure oil output. The high-pressure oil enters the lifting cylinder control oil passage through port B, and then enters the rodless chamber of each lifting cylinder 3 through the lifting cylinder oil outlet. The piston rod of the lifting cylinder 3 extends under the action of high-pressure oil, pushing the lifting plate 31 to rise. When the lifting plate 31 rises to the top, its top surface is flush with the top surface of the guide rail 11, and the positioning port 111 is completely blocked, forming a continuous track. The moving platform 2 is supported by the traveling wheels 21 and can be pushed smoothly. The traveling wheels 21 pass smoothly through the original positioning port 111 position via the lifting plate 31 without vibration or impact.

[0044] S2: After the moving table 2 is pushed to the stamping station along the guide rail 11, the PLC controller stops the motor 5. The rodless chamber of the lifting cylinder 3 is connected to the T port through the B port of the electromagnetic reversing valve 81. The oil in the rodless chamber is pressed back into the oil tank under the action of the self-weight of the driving end of the lifting cylinder 3 and the gravity of the moving table 2. The piston rod of the lifting cylinder 3 retracts, the lifting plate 31 descends, and the positioning port 111 reopens. The traveling wheel 21 falls exactly into the positioning port 111, and the bottom surface of the moving table 2 is in contact with the top surface of the worktable 1, achieving initial positioning. S3: After the moving stage 2 is in position, the PLC controller controls the motor 5 to start again and controls the solenoid directional valve 81 to maintain the first working state (P port connected to A port, B port connected to T port). High-pressure oil enters the inlet of the hydraulic control check valve 82 through the P port and A port, then enters the control oil passage of the clamping cylinder through the outlet of the hydraulic control check valve 82, and finally enters the rod chamber of each clamping cylinder 4. The piston rod of the clamping cylinder 4 moves downward under the pressure of the high-pressure oil, driving the clamping plate 41 to press down, while compressing the compression spring in the rodless chamber. The clamping plate 41 passes through the through groove of the moving stage 2 and abuts against the pressing edge 22 on the inner side wall of the through groove, applying a downward clamping force to the moving stage 2 and firmly fixing the moving stage 2 to the worktable 1.

[0045] When the pressure in the clamping chamber rises to the set value of the pressure relay 83, the pressure relay 83 sends an electrical signal to the PLC controller, which then controls the motor 5 to stop operating. At this time, the pressure in the clamping chamber is maintained by the first one-way valve 7 and the hydraulic one-way valve 82, achieving long-term pressure maintenance without continuous motor operation, thus saving energy. In this clamping state, the punch press can perform punching operations on the workpiece on the moving table 2 without any displacement of the moving table 2, ensuring processing accuracy and safety. S4: After the stamping operation is completed, the moving table 2 needs to be moved out of the worktable 1. At this time, the PLC controller controls the motor 5 to start and controls the solenoid directional valve 81 to switch to the second working state (P port is connected to B port, A port is connected to T port). High-pressure oil enters the lifting cylinder control oil passage through P port and B port, and at the same time enters the control oil port of the hydraulic control check valve 82 through the branch oil passage. The high-pressure oil in the lifting cylinder control oil passage enters the rodless chamber of each lifting cylinder 3, the piston rod of the lifting cylinder 3 extends, and pushes the lifting plate 31 to rise and block the positioning port 111. At the same time, after the control oil port of the hydraulic control check valve 82 receives the pressure signal, the hydraulic control check valve 82 is forcibly opened, so that the clamping cylinder control oil passage is connected to the A port of the solenoid directional valve 81. The oil in the rod chamber of the clamping cylinder 4 is squeezed out under the action of the compression spring return force, and flows back to the oil tank through the clamping cylinder control oil passage, the hydraulic control check valve 82, and the A and T ports of the solenoid directional valve 81. The piston rod of the clamping cylinder 4 moves upward under the action of the compression spring, causing the clamping plate 41 to move away from the pressing edge 22, thus releasing the clamp on the moving stage 2. At this point, the moving stage 2 can be smoothly pushed out in the raised state.

[0046] S5: After the lifting chamber reaches the set value of the pressure relay 83, the pressure relay 83 sends another signal, and the PLC controller controls the motor 5 to stop. The system maintains the pressure and lifts the state, and the moving platform 2 can be moved out. After the moving platform 2 is moved out, the solenoid reversing valve 81 switches to the first working state, the lifting cylinder 3 repositions itself, and the system enters the next working cycle.

[0047] Throughout the entire operation, the electromagnetic directional valve 81 only needs to switch between two working positions to sequentially achieve the linkage control of clamping and pressure holding during clamping and automatic release during lifting, without the need for complex sequence valves or additional control oil sources. In particular, the design of the branch oil passage ensures that the hydraulic control check valve 82 is forcibly opened at the same time as the lifting action is initiated, and the clamping cylinder 4 automatically releases, realizing the linkage between lifting and clamping release, avoiding misoperation, and greatly improving the safety and reliability of the system.

[0048] The above description is merely a preferred embodiment of the present invention and is not intended to limit the present invention. It should be noted that for those skilled in the art, several improvements and modifications can be made without departing from the technical principles of the present invention, and these improvements and modifications should also be considered within the scope of protection of the present invention.

Claims

1. A clamping and lifting device for a moving worktable of a punch press, characterized in that: The press includes a worktable (1) mounted on the press body and a movable stage (2) movable onto the worktable (1). The movable stage (2) has several traveling wheels (21) arranged in a rectangular array at its bottom. A guide rail (11) is fixedly connected to the worktable (1) to cooperate with the traveling wheels (21). The guide rail (11) has positioning openings (111) corresponding to each of the traveling wheels (21). Several clamping modules for clamping the movable stage (2) are provided on the worktable (1). A lifting module for raising the movable stage (2) so that the traveling wheels (21) disengage from the positioning openings (111) is provided at the bottom of the worktable (1). The press also includes a linkage module for driving the clamping modules and the lifting module. The linkage module includes a power source module and a control logic module; the lifting module includes several lifting cylinders (3) vertically arranged at the bottom of the worktable (1), and the clamping module includes several clamping cylinders (4) vertically arranged at the bottom of the worktable (1) and located on one side of the guide rail (11); the input end of the power source module is connected to the oil tank, the control logic module includes an electromagnetic reversing valve (81) and a hydraulic control check valve (82), the output end of the power source module is connected to the input end of the electromagnetic reversing valve (81), the return end of the electromagnetic reversing valve is also connected to the oil tank, the electromagnetic reversing valve (81) has two output ends, one of which is connected to several clamping cylinders through the hydraulic control check valve (82), and the other... The output terminal is connected to the lifting cylinder (3) and in parallel with the control port of the hydraulic check valve (82) to force the hydraulic check valve (82) to open when oil enters the lifting cylinder (3), so that the clamping cylinder (4) unloads oil; the control logic module is integrated on a valve block (8), the side of the valve block (8) is provided with a clamping cylinder outlet and a lifting cylinder outlet, the valve block (8) is provided with an inlet oil passage, a return oil passage, a clamping cylinder control oil passage and a lifting cylinder control oil passage, the output terminal of the power source module is connected to the inlet oil passage of the valve block (8), the return oil passage of the valve block (8) is connected to the oil tank through a pipeline, the return oil end of the electromagnetic reversing valve (81) is connected to the return oil passage, and the input terminal of the electromagnetic reversing valve (81) is connected to the inlet oil passage. The oil passages are connected. One output end of the electromagnetic reversing valve (81) is connected to the clamping cylinder control oil passage through the hydraulic control check valve (82), and the other end is connected to the lifting cylinder control oil passage. A branch oil passage is also provided in the valve block (8). One end of the branch oil passage is connected to the lifting cylinder control oil passage, and the other end is connected to the control oil port of the hydraulic control check valve (82) so as to force the hydraulic control check valve (82) to open when oil enters the lifting cylinder control oil passage. The clamping cylinder outlet is connected to the clamping cylinder control oil passage, and the lifting cylinder outlet is connected to the lifting cylinder control oil passage. The clamping cylinder outlet is connected to the rod chamber of each clamping cylinder (4) through a pipeline, and the lifting cylinder outlet is connected to the rodless chamber of each lifting cylinder (3) through a pipeline.

2. The clamping and lifting device for a moving worktable of a punch press according to claim 1, characterized in that: The number of lifting cylinders (3) corresponds to the number of traveling wheels (21). The driving end of the lifting cylinder (3) is fixedly connected to a lifting plate (31). The top of the lifting plate (31) contacts the outer peripheral wall of the traveling wheel (21). When the driving end of the lifting cylinder (3) moves to the maximum stroke position, the lifting plate (31) rises to the top and its top surface is flush with the top surface of the guide rail (11), forming a continuous track and sealing the positioning port (111).

3. The clamping and lifting device for a moving worktable of a punch press according to claim 2, characterized in that: The lifting cylinder (3) is vertically arranged and the hydraulic oil is connected to the rodless cavity of the lifting cylinder (3). When there is no pressure oil in the lifting cylinder (3), the driving end of the lifting cylinder (3) is reset by its own gravity, which drives the lifting plate (31) to descend, so that the positioning port (111) is fully open.

4. The clamping and lifting device for a moving worktable of a punch press according to claim 1, characterized in that: The piston rod end of the clamping cylinder (4) passes through the workbench (1) and is fixedly connected to the clamping plate (41). The moving table (2) is provided with a through groove for the clamping plate (41) and the piston rod of the clamping cylinder (4) to pass through. The inner side wall of the through groove is symmetrically provided with pressing edges (22) that cooperate with the clamping plate (41).

5. The clamping and lifting device for a moving worktable of a punch press according to claim 4, characterized in that: The bottom surface of the pressing edge (22) is flush with the bottom surface of the moving platform (2). The piston rod of the clamping cylinder (4) drives the clamping plate (41) to press down and abut against the pressing edge (22), applying a downward clamping force to the moving platform (2).

6. The clamping and lifting device for a moving worktable of a punch press according to claim 5, characterized in that: A compression spring is provided in the rodless chamber of the clamping cylinder (4). When oil enters the rod chamber of the clamping cylinder (4) and the piston rod retracts, the piston rod applies an external force to the compression spring to cause it to compress and deform. When oil is discharged from the rod chamber of the clamping cylinder (4), the compression spring resets, pushes the piston rod to extend, and drives the clamping plate (41) away from the pressing edge (22).

7. The clamping and lifting device for a moving worktable of a punch press according to claim 1, characterized in that: The solenoid directional valve (81) is a two-position four-way solenoid directional valve. Its P port is connected to the oil inlet, its T port is connected to the oil return, its A port is connected to the oil inlet of the hydraulic control check valve (82), and its B port is connected to the control oil passage of the lifting cylinder.

8. The clamping and lifting device for a moving worktable of a punch press according to claim 1, characterized in that: The power source module includes a motor (5), a pressure-compensated variable pump (6), and a first check valve (7). The output shaft of the motor (5) is driven to be connected to the input shaft of the pressure-compensated variable pump (6). The oil inlet of the pressure-compensated variable pump (6) is submerged below the oil level in the tank, and its outlet is connected to the inlet of the first check valve (7) through a pipeline. The outlet of the first check valve (7) is connected to the oil inlet of the valve block (8).

9. The clamping and lifting device for a moving worktable of a punch press according to claim 1, characterized in that: The control logic module also includes a pressure relay (83), which is installed on the valve block (8) and has two detection ports that are connected to the clamping cylinder control oil passage and the lifting cylinder control oil passage, respectively, to detect the clamping pressure and the lifting pressure and convert the pressure signal into an electrical signal.

10. The clamping and lifting device for a moving worktable of a punch press according to claim 1, characterized in that: A main pipe connects the valve block (8) and several clamping cylinders (4). A tee is connected to the main pipe. One end of the tee is connected to each clamping cylinder (4) through various pipes, and the other end is connected to a maintenance solenoid valve (100). The end of the maintenance solenoid valve (100) away from the tee is connected to the oil tank.

11. A control method for a clamping and lifting device for a moving worktable of a punch press, used for controlling the clamping and lifting device according to any one of claims 1-10, characterized in that, Includes the following steps: S1: Drive the lifting module to move through the linkage module, so that the lifting module rises and blocks the positioning port (111) to form a continuous track, and move the moving table (2) into the worktable (1); S2: Control the linkage module to reset the lifting module, and the moving platform (2) descends so that the walking wheel (21) falls into the positioning port (111) to achieve the initial positioning of the moving platform (2) on the workbench (1); S3: The clamping module is driven by the linkage module to apply clamping force to the moving table (2), and the moving table (2) is fixed on the worktable (1) for stamping operation; S4: After stamping is completed, the lifting action and clamping release action are performed synchronously through the linkage module. That is, the linkage module drives the lifting module to lift the moving table (2), and at the same time, the linkage module controls the clamping module to release the clamping of the moving table (2). S5: Move the mobile stage (2) out of the worktable (1).

12. The control method for the clamping and lifting device of the moving worktable of a punch press according to claim 11, characterized in that: In step S4, the linkage module includes an electromagnetic reversing valve (81) and a hydraulic control check valve (82). The linkage module supplies oil to the rodless chamber of the lifting cylinder (3) to drive the lifting module to lift the moving platform (2). At the same time, it supplies oil to the control port of the hydraulic control check valve (82) through the branch oil passage opened in the valve block (8), forcibly opening the hydraulic control check valve (82), so that the rod chamber of the clamping cylinder (4) is connected to the oil tank through the return oil end of the hydraulic control check valve (82) and the electromagnetic reversing valve (81). The piston rod of the clamping cylinder (4) is reset under the action of the compression spring in the rodless chamber, driving the clamping plate (41) away from the pressing edge (22) and releasing the clamping of the moving platform (2).

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