Progressive die with adaptive scrap cutting function

Abstract

This invention relates to the field of stamping forming technology and discloses a progressive die with adaptive scrap cutting function, including an upper die base, a lower die base, a stripper plate, a cutting punch slidably disposed in the upper die base, and a scrap die disposed on the lower die base; the stripper plate is connected to the lower part of the upper die base through a stripping elastic element and generates a vertical relative displacement with the upper die base during stamping; it also includes a driving assembly and a force transmission pad that is driven by the driving assembly to switch between a bearing position and a clearance position, the force transmission pad being located above the cutting punch and having a locking part; a locking pin, slidably assembled in the upper die base, and having a locking tendency to insert into the locking part under the action of elastic preload; an unlocking rod, disposed on the stripper plate, and forming a linkage limit with the locking pin. This invention can adapt to intermittent scrap cutting, reduce the pneumatic relief effect of traditional cylinder pads, ensure that the cutting punch is centered under force, avoid unilateral wear and cracking of the cutting edge, and extend the die life.

Description

Technical Field

[0001] This invention relates to the field of stamping technology, and more specifically, to a progressive die with an adaptive waste cutting function. Background Technology

[0002] Progressive die devices are widely used in the current market for producing sheet metal parts for automobiles, electronic appliances, hardware, and construction, meeting the market's demand for high-speed, high-volume production. Existing technologies, such as the Chinese utility model patents with authorization announcement numbers CN223338190U and CN214391953U, integrate multiple processes such as punching, trimming, bending, and cutting into a single die, significantly improving production efficiency and avoiding errors and safety hazards associated with multiple equipment transfers.

[0003] However, in continuous high-speed stamping production, intermittent scrap cutting (i.e., adaptive cutting) is often required based on the layout process. Existing adaptive cutting structures typically have a laterally moving force-transmitting pad above the cutting punch, relying on a cylinder to directly push and pull the pad to determine whether to transmit force. However, in actual heavy-load cutting moments, the cutting reaction force can reach hundreds of kilonewtons. Due to the compressibility of gas (i.e., pneumatic yielding effect), the force-transmitting pad is prone to slight yielding or tangential slippage when subjected to huge vertical forces. This causes the top of the cutting punch to lose rigid support, and the force cannot be centered and aligned, resulting in uneven wear and cracking of the punch cutting edge on one side, severely shortening the die life.

[0004] Therefore, there is an urgent need for a progressive die with adaptive waste cutting function to at least partially solve the above technical problems. Summary of the Invention

[0005] To at least partially address the problems in the prior art, this invention provides a progressive die with adaptive scrap cutting function, including an upper die base, a lower die base, a stripper plate, a cutting punch slidably disposed within the upper die base, and a scrap die disposed on the lower die base; the stripper plate is connected to the lower part of the upper die base via a stripping elastic element and generates a relative displacement in the vertical direction with the upper die base during stamping; it also includes: The driving component and the force transmission pad that is driven by the driving component to switch between the bearing position and the avoidance position, the force transmission pad is located above the cutting punch and is provided with a locking part; The locking pin is slidably assembled in the upper mold base and has a locking tendency to insert into the locking part under the action of elastic preload. The unlocking lever is located on the unloading plate and forms a linkage limit with the locking pin; When the unloading plate and the upper mold base move closer to each other, the unlocking rod releases the blocking limit on the locking pin. Under the action of elastic preload, the locking pin engages with the locking part, locking the force transmission pad block in the bearing position.

[0006] Preferably, the locking part is a groove formed at one end of the force transmission pad; The locking pin is a horizontally sliding locking pin installed in the upper mold base, with one end facing the groove and the other end abutting against a locking elastic element that provides elastic pre-tightening force. The middle section of the locking pin has a through groove, the unlocking rod extends upward through the through groove and has a blocking section machined on its upper part, and a wedge-shaped inclined surface that smoothly transitions to the blocking section is machined below the blocking section; during relative displacement, the blocking section slides upward out of the through groove so that the wedge-shaped inclined surface releases the lateral obstruction to the locking pin.

[0007] Preferably, the end face of the locking pin 8 opposite the groove is formed as a wedge-shaped inclined surface, and the inner wall of the groove is machined with a mating inclined surface that fits against the wedge-shaped inclined surface; the contact surface formed by the fit between the normal of the wedge-shaped inclined surface and the mating inclined surface has an angle of θ with the horizontal direction. The static friction coefficient of the contact surface material is ,and .

[0008] Preferably, the bottom of the unlocking rod is provided with a T-shaped flange, and the unloading plate is provided with a T-shaped groove that fits the T-shaped flange with a clearance. The two work together to form a radial floating structure so that the unlocking rod only transmits vertical movement.

[0009] Preferably, a pin is provided inside the through groove, and a cam roller is rotatably connected to the pin. The surface of the unlocking rod forms a rolling contact with the cam roller. A self-lubricating copper sleeve is fitted on the sliding outer circle surface of the locking pin.

[0010] Preferably, in the internal cavity of the upper mold base where the locking pin is assembled, exhaust channels connecting to the outside of the mold base are provided at the blind end near the locking part and at the tail end where the locking elastic element is accommodated.

[0011] Preferably, the force transmission pad has dovetail guide rails machined on both sides, and the upper mold base has a dovetail groove that matches the dovetail guide rails; the force transmission pad has a limiting block with a buffer pad; and the end of the locking pin has an inlet chamfer.

[0012] Preferably, the progressive die also includes a control system, which includes a material detection sensor disposed on the lower die holder side, an encoder for acquiring the real-time angle of the punch press spindle, and a controller electrically connected to the material detection sensor, the encoder, and the drive assembly. The controller is equipped with a dynamic advance angle conversion module, which performs time derivative on the acquired real-time angle to obtain the real-time angular velocity of the punch press. ; Call the response time constant of the pre-stored driver component Calculate the angle compensation amount According to the preset target safe positioning angle The dynamic trigger angle is calculated in reverse. When it is determined that scrap cutting needs to be performed, and the real-time angle of the punch press reaches the dynamic trigger angle. At that time, a trigger command is sent to the driving component.

[0013] Preferably, position detection elements are provided at both ends of the drive component, and the controller performs sliding average time calibration: in the non-cut-off dry-fire state, the actual action time from the issuance of the trigger command to the triggering of the position detection element is recorded; a sliding average filtering algorithm is used to extract the average of the most recent N actual action times to dynamically update the response time constant. .

[0014] Preferably, the controller performs active unloading and unlocking: during the return stroke stage after the waste material is cut off and the punch passes the bottom dead center, before the unloading plate resets downward relative to the upper die seat and the locking pin is pushed back by the unlocking rod, a retraction command is issued to the drive assembly in advance; by controlling the drive assembly to pull the force transmission pad backward, the static friction state between the locking part and the locking pin contact surface is broken, and then the unlocking rod completes the mechanical unlocking.

[0015] Compared with the prior art, the present invention provides a progressive die with adaptive waste cutting function, which can adapt to the intermittent cutting of waste, and has at least the following beneficial effects: The inherent relative displacement generated when the stripper plate and the upper die holder close together is used as a mechanical trigger source. The pre-tightened locking pin is released through the wedge-shaped inclined surface of the unlocking rod, achieving pure mechanical locking of the force transmission pad at the moment of die closing and cutting. This minimizes the pneumatic yielding effect of traditional cylinder pads, ensures that the cutting punch is centered under force, avoids one-sided wear and cracking of the cutting edge, and extends the die life.

[0016] By using a dynamic advance angle conversion program, the angular velocity of the punch press is measured in real time, and the fixed response time of the drive component is adaptively converted into a dynamic trigger angle. This allows the force transmission pad to be positioned in advance, ensuring smooth and unobstructed subsequent mechanical locking actions, and solving the interference and collision problem caused by the mismatch between air supply delay and mechanical frequency conversion action timing. Attached Figure Description

[0017] The accompanying drawings are provided to further illustrate the invention and form part of the specification. They are used in conjunction with embodiments of the invention to explain the invention and do not constitute a limitation thereof. In the drawings: Figure 1 This is a schematic diagram of the progressive die in the open state in this invention; Figure 2 This is a schematic diagram of the progressive die in the present invention when it is in a conventional stamping state; Figure 3 This is a schematic diagram of the progressive die in the present invention during the cutting operation; Figure 4 This is a schematic diagram of the cross-sectional structure of the upper mold base at the force transmission pad in this invention; Figure 5 This is a schematic cross-sectional view of the locking pin in this invention; Figure 6 This is a block diagram of the electrical connections of the control system in this invention.

[0018] In the figure: 1. Upper die base; 2. Lower die base; 3. Stripper plate; 4. Cutting punch; 5. Scrap die; 6. Drive assembly; 7. Force transmission pad; 71. Locking part; 72. Dovetail guide rail; 8. Locking pin; 81. Locking elastic element; 82. Through groove; 9. Unlocking rod; 91. Wedge-shaped inclined surface. Detailed Implementation

[0019] The present invention will now be described in further detail with reference to the accompanying drawings and embodiments, so that those skilled in the art can implement it based on the description.

[0020] Example 1: As Figures 1-5 As shown, this embodiment provides a progressive die with adaptive waste cutting function, including an upper die base 1, a lower die base 2, a stripper plate 3, a cutting punch 4 slidably disposed in the upper die base 1, and a waste die 5 disposed on the lower die base 2. The stripper plate 3 is connected to the lower part of the upper die base 1 through a stripping elastic element, and generates a relative displacement in the vertical direction with the upper die base 1 during stamping.

[0021] The upper die holder 1 has a stepped punch guide hole vertically opened inside. The cutting punch 4 is slidably assembled in the punch guide hole. The top end of the cutting punch 4 has an anti-detachment step with a diameter larger than its lower end. The anti-detachment step is axially suspended on the inner step surface of the punch guide hole. The stripper plate 3 has a punch through hole vertically opened at the position directly below the cutting punch 4. The bottom cutting edge of the cutting punch 4 can pass downward through the punch through hole.

[0022] The progressive die also includes a drive assembly 6 and a force transmission pad 7 that is driven by the drive assembly 6 to switch between a bearing position and a clearance position. The drive assembly 6 can be a pneumatic push rod cylinder or a hydraulic cylinder. The force transmission pad 7 is located above the cutting punch 4 and is provided with a locking part 71. The locking part 71 is configured as a groove formed at the end of the force transmission pad 7, or as a snap-fit ​​stepped surface, a pin hole, or a stop protrusion provided on the side wall of the force transmission pad 7.

[0023] The upper mold base 1 has a dovetail groove arranged horizontally through the interior, which serves as a transverse cavity for accommodating the horizontal sliding of the force transmission pad 7; the upper mold base 1 also has a punch guide hole arranged vertically, which serves as a vertical cavity for accommodating the vertical reciprocating movement of the cutting punch 4; the punch guide hole is connected to the transverse cavity.

[0024] The progressive die also includes a locking pin 8 and an unlocking rod 9. The locking pin 8 is slidably fitted inside the upper die holder 1 and, under the action of elastic preload, has a locking tendency to insert into the locking part 71. The unlocking rod 9 is provided on the stripper plate 3 and forms a linkage limit with the locking pin 8.

[0025] The working principle and beneficial effects of the above technical solution are as follows: In the conventional stamping state without scrap cutting: when the die is in the open state, the stripper plate 3 is held at the bottom of the vertical stroke relative to the upper die holder 1 by the downward pushing force of the stripper elastic element. At this time, the cutting punch 4 is suspended in the upper die holder 1 by the anti-detachment step on its top, and its lower cutting edge is suspended in the punch through hole of the stripper plate 3. When the die moves down to close, the stripper plate 3 first contacts and presses the strip to stop moving down. The upper die holder 1 continues to move down and compresses the stripper elastic element, so that the upper die holder 1 and the stripper plate 3 have a relative displacement that brings them closer to each other. During this process, since the force transmission pad 7 is kept in a position away from the cutting punch 4, the top of the cutting punch 4, due to the lack of a rigid force transmission medium, is pushed upward by the strip when it contacts the strip and retreats into the cavity of the upper die holder, thus not performing the cutting action and realizing dry stamping.

[0026] When a cutting operation is required, the drive assembly 6 extends, pushing the force transmission pad 7 horizontally into the bearing position directly above the cutting punch 4. As the press slide continues to descend and the die closes, the bottom of the stripper plate 3 first contacts the surface of the metal strip generated by the stamping inside the progressive die and stops descending. At this time, the upper die holder 1 continues to press down with the press slide, causing a vertical relative displacement between the stripper plate 3 and the upper die holder 1, bringing them closer together.

[0027] Since the unlocking rod 9 is vertically fixed on the stripper plate 3, when the stripper plate 3 and the upper die base 1 move closer together, the unlocking rod 9 moves upward relative to the upper die base 1, thereby releasing the blocking limit on the locking pin 8. Under the action of the elastic preload, the locking pin 8 moves horizontally and engages with the locking part 71. At this time, the locking pin 8 rigidly locks the force transmission pad 7, which is in the bearing position. The upper die base 1 is pressed to the bottom dead center, and the cutting impact force is transmitted upward to the force transmission pad 7 through the cutting punch 4. Due to the purely mechanical linkage locking of the locking pin 8, the force transmission pad 7 has zero retraction when subjected to high axial load, and the cutting force is converted into a completely vertical shearing force to complete the waste cutting.

[0028] In the above-mentioned operation, the locking pin 8 and the force transmission pad 7 are arranged opposite each other along the coaxial horizontal line. The locking pin 8 is used to overcome the transient horizontal displacement caused by the high-frequency and high-load vibration of the mold, and to ensure that the bearing surface of the force transmission pad 7 is vertically coincident with the top surface of the cutting punch 4 at the moment of vertical mold closing.

[0029] This embodiment can adapt to intermittent cutting of waste material, using the inherent mechanical displacement of the die, i.e., the relative displacement between the stripper plate 3 and the upper die holder 1, as the self-locking trigger source. The relative displacement is converted into a release command for the locking pin 8, forming a purely mechanical conversion path. This design achieves pure mechanical rigid locking without pneumatic intervention at the moment of cutting, reducing or preventing tangential slippage of the locking pin 8 when subjected to cutting reaction forces of hundreds of kilonewtons, thus achieving rigid positioning of the force transmission pad 7. The synergistic effect of the above mechanical structures eliminates the pneumatic yielding effect, ensuring that the cutting punch 4 is centered and aligned under force, avoiding unilateral wear and cracking of the cutting edge, and increasing the die's lifespan under continuous stamping conditions.

[0030] Example 2: Based on Example 1 above, the locking part 71 is specifically a groove formed at one end of the force transmission pad 7. The locking pin 8 is a horizontally sliding locking pin installed in the upper mold base 1, with one end facing the groove and the other end abutting against a locking elastic member 81 that provides elastic preload. The locking elastic member 81 is set as a helical spring or a disc spring.

[0031] The middle section of the locking pin 8 has a square-shaped through groove 82 that extends vertically through it, and the unlocking rod 9 extends upward through the through groove 82. Specifically, the unlocking rod 9 is divided into a blocking section, a wedge-shaped inclined surface 91 as a transition surface, and a narrow section for avoidance along the vertical direction from top to bottom; the wedge-shaped inclined surface 91 is arranged to gradually become thinner and narrower from top to bottom.

[0032] The working principle and beneficial effects of the above technical solution are as follows: With the progressive die in its initial open state (top dead center), the drive assembly 6 remains retracted, and the force transmission pad 7 is in a clearance position on the left. At this time, since the stripper plate 3 is in its lowest position, the unlocking rod 9 fixed on the stripper plate 3 is simultaneously in its lowest stroke position. In this state, the thicker blocking section at the top of the unlocking rod 9 passes through the through groove 82 of the locking pin 8. The thicker blocking section presses against the inner wall of the through groove 82, overcoming the leftward pushing force of the locking elastic element 81, thereby forcibly intercepting and locking the horizontal locking pin 8 inside the right blind hole, preventing it from moving to the left, allowing the force transmission pad 7 to slide freely.

[0033] When the scrap is cut off, the drive assembly 6 extends to the right, pushing the force transmission pad 7 horizontally to the bearing position directly above the cutting punch 4. At this time, the groove on the right end face of the force transmission pad 7 spans the spatial gap and precisely aligns with the left end of the horizontal locking pin 8. Subsequently, the punch slide descends to close the mold, the stripper plate 3 presses the metal strip and stops descending, and the upper die holder 1 continues to press down with the slide, causing the upper die holder 1 and the stripper plate 3 to have a vertical relative displacement that brings them closer together. During this stroke, the unlocking rod 9 fixed on the stripper plate 3 slides upward relative to each other, causing the thicker blocking section to gradually slide upward out of the through groove 82, while the wedge-shaped inclined surface 91, which gradually thins from top to bottom, and the lowest clearance section gradually enter and pass through the interior of the through groove 82. As the thinner wedge-shaped inclined surface 91 and clearance section enter the through groove 82, the horizontal movement space left for the inner wall of the through groove 82 gradually increases, that is, the horizontal blocking limit on the inner wall of the through groove 82 is smoothly released or eliminated. The horizontal locking pin 8 moves instantaneously to the left under the axial leftward thrust of the locking elastic member 81, and the guide chamfer at its end slides into and locks into the groove of the force transmission pad 7, forming a positive interception and blocking on the force transmission pad 7 in the horizontal movement direction.

[0034] At the moment when the upper die holder 1 is pressed to the bottom dead center to perform heavy-duty cutting, the vertical shearing impact force is transmitted upward. The absolutely horizontal upper and lower surfaces of the force transmission pad 7 are completely overlapped and pressed with the top surface of the dovetail groove of the upper die holder and the top surface of the cutting punch 4. Under the action of the vertical pressing force, a friction deadlock is formed in the horizontal sliding direction. With the axial positive interception of the locking pin 8, zero-yield waste material cutting is achieved.

[0035] When the cut-off end of the punch press slide drives the upper die holder 1 to return upward, before the stripper plate 3 resets downward, the controller sends a reverse retraction command to the drive assembly 6 in advance to complete the active unloading. Subsequently, the stripper plate 3 resets downward under the drive of the stripper elastic element, pulling the unlocking rod 9 downward and moving the horizontal locking pin 8 to the right to reset.

[0036] In this embodiment, by designing the unlocking rod 9 as a structure that is thicker at the top and thinner at the bottom with a gradually changing slope in the middle, the vertical relative displacement between the upper mold base 1 and the unloading plate 3 can be used to achieve passive locking and unlocking of the locking pin 8, eliminating the risk of failure of the electronic switch under high-frequency impact and ensuring the ultimate operating life of the adaptive cutting mold.

[0037] As an optional embodiment, the bottom of the unlocking rod 9 is provided with a T-shaped flange, and the unloading plate 3 is provided with a T-shaped groove that fits the T-shaped flange with a clearance.

[0038] During the downward stamping stage of the progressive die, where the stripper plate 3 and the upper die holder 1 experience relative displacement, the unlocking rod 9 with the T-flange moves synchronously with the stripper plate 3. If the stripper plate 3 tilts slightly due to uneven force at the workstation, the clearance between the T-flange and the T-slot absorbs the radial displacement in the horizontal plane, preventing the unlocking rod 9 from bending and ensuring that the unlocking rod 9 only transmits vertical upward motion into the through slot 82. The radial floating structure formed by the clearance fit between the T-flange and the T-slot adaptively absorbs and isolates the off-center tilt of the stripper plate 3, ensuring the smoothness of the vertical movement of the unlocking rod 9.

[0039] As another optional implementation of this embodiment, the bottom of the unlocking rod 9 is machined into an outer spherical column head; a floating seat is embedded in the unloading plate 3, and a cross-shaped sliding groove is opened on the unloading plate 3. The top of the floating seat is machined with an inner spherical surface that precisely matches the outer spherical column head, and the two cooperate to form a spherical pair; the bottom of the floating seat is machined with a cross-shaped guide protrusion, which slides into the cross-shaped sliding groove so that the unlocking rod 9 only transmits vertical movement.

[0040] Under the harsh conditions of high-speed stamping with progressive dies, uneven material distribution or unbalanced forces at each station can easily lead to a slight angular off-center load (i.e., slight tilting) when the stripper plate 3 contacts the strip. This embodiment introduces a three-dimensional floating structure, allowing the spherical pair formed by the outer spherical head and the inner spherical surface to rotate freely, adaptively eliminating the slight angular tilt of the stripper plate 3 in any direction. Simultaneously, the sliding of the cross guide protrusion along the cross-shaped groove absorbs the radial displacement offset in the horizontal plane. This ensures that the unlocking rod 9 can isolate deformation interference at the bottom under any off-center load or tilting condition, transmitting only axial vertical thrust into the through groove 82, thus preventing the unlocking rod 9 from flexing, scraping against the inner wall of the through groove 82, jamming, or fatigue fracture.

[0041] Example 3: Based on Example 2 above, the insertion end face of the locking pin 8 is not a vertical plane, but is processed into an inclined surface with an inward angle (i.e., a component force that squeezes the locking pin into the blind hole under the action of the cutting reaction force). Correspondingly, the inner side wall of the groove of the force transmission pad 7 is processed into a mating inclined surface.

[0042] The end face of the locking pin 8 and the contact surface of the groove satisfy specific frictional self-locking conditions: the angle between the normal of the contact surface and the horizontal direction is set to... The static friction coefficient of the contact surface material is The two satisfy geometric constraints. Furthermore, the surface roughness of the contact surface is precision ground to... .

[0043] The inclined surface structure, combined with the self-locking formula, ensures that the locking pin 8 smoothly slides into the groove to eliminate the fit gap using the inclined surface guide, and also ensures that when subjected to heavy cutting reaction force, the tangential component of the force generated on the contact surface is completely absorbed by static friction, achieving true sliding self-locking. The force transmission pad 7 cannot push the locking pin 8 outward, achieving purely mechanical positioning, thus converting the impact force into a complete positive pressure, which reduces or prevents the locking pin 8 from tangentially slipping out when subjected to cutting reaction force.

[0044] Example 4: Based on Example 2 above, a pin is provided inside the through groove 82, and a cam roller is rotatably connected to the pin. The surface of the unlocking rod 9 forms a rolling contact with the cam roller. A graphite-inlaid self-lubricating copper sleeve is fitted on the sliding outer circular surface of the locking pin 8.

[0045] In the internal cavity of the upper mold base 1 where the locking pin 8 is assembled, exhaust channels that connect to the outside of the mold base are provided at the blind end near the locking part 71 and at the tail end where the locking elastic member 81 is accommodated.

[0046] The working principle and beneficial effects of the above technical solution are as follows: When the mold enters a high-frequency stamping cycle of hundreds of times per minute, the unlocking rod 9 moves back and forth with the unloading plate 3 at high frequency. In this embodiment, as the unlocking rod 9 rises and falls, the cam roller rotates clockwise or counterclockwise around the pin shaft, converting the original high-resistance sliding friction into rolling friction, reducing the surface friction wear between the unlocking rod 9 and the inner wall of the through groove 82 during mechanical unlocking, and achieving smooth passive limiting and release. At the moment the limit is released, the locking pin 8 moves horizontally under the thrust of the locking elastic element 81, and the air in the chamber is discharged or replenished through the exhaust channel, maintaining a real-time balance with the external atmospheric pressure. The outer circular surface of the horizontal locking pin 8 slides on the microscopic graphite lubrication layer of the self-lubricating copper sleeve, completing the movement action without lag.

[0047] Example 5: Based on Example 1 above, dovetail guide rails 72 are machined on both sides of the force transmission pad 7, and a dovetail groove that mates with the dovetail guide rails 72 is opened inside the upper mold base 1. A limiting block with a buffer pad is provided on the force transmission pad 7, which is specifically set at the limit position of the travel along the dovetail groove, and the buffer pad can be a polyurethane buffer pad. The end face of the locking pin 8 is machined with an inlet chamfer.

[0048] The working principle and beneficial effects of the above technical solution are as follows: During the adaptive cutting action, the drive component 6 actuates, pushing the force transmission pad 7 to slide horizontally and rapidly into the dovetail groove inside the upper mold base 1. The geometrical envelopment of the dovetail guide rail 72 by the dovetail groove restricts the freedom of the force transmission pad 7 in the vertical and up-and-down flipping directions, ensuring that the force transmission pad 7 slides horizontally with a pure single degree of freedom. The force transmission pad 7 finally stops upon impacting the limiting block embedded with a polyurethane buffer pad, completing the initial positioning and alignment. Using the chamfered bevel, the locking pin 8 slides precisely into the locking part 71.

[0049] Example 6: As Figure 6 As shown, based on Embodiment 1 above, the progressive die also includes a control system. The control system includes a material detection sensor disposed on the lower die holder side, an encoder for acquiring the real-time angle of the punch press spindle, and a controller electrically connected to the material detection sensor, the encoder, and the drive assembly 6. The controller includes a dynamic advance angle conversion module.

[0050] During the continuous stamping process of the progressive die, the controller continuously monitors the output signal of the material detection sensor. When the scrap strip extends along the scrap discharge channel of the lower die holder 2 to a set length and blocks the sensor beam, the controller internally determines and triggers an adaptive cut-off command.

[0051] When the judgment condition is met, the controller starts its internal dynamic advance angle conversion program: First, the controller receives the current angle data of the punch press from the high-frequency input of the encoder. The controller then obtains the real-time angular velocity based on the angle change of the encoder per unit time. Subsequently, the response time constant of the pre-stored driver component 6 is invoked. .

[0052] Next, the controller automatically performs a multiplication operation to calculate the angle compensation amount. .

[0053] Subsequently, the controller extracts the preset target safe positioning angle. (In this embodiment, the angle is set to 340°, meaning the progressive die is in a fully open state, and the unloading plate 3 moves downward with the upper die holder 1 but has not yet contacted the material in the safe timing gap phase.) The dynamic trigger angle is calculated in reverse: .

[0054] The controller will compare the current real-time angle with the calculated angle. Real-time comparison is performed. When the spindle angle reaches the dynamic trigger angle... At that moment, the controller immediately sends a trigger command to the drive component 6. The drive component 6 then begins to extend, undergoing a fixed process. After a certain period of time, the piston rod is fully extended, at which point the force transmission pad 7 is in place, and the angle of the punch press spindle precisely reaches the target position of 340°.

[0055] The beneficial effects of the above technical solution are as follows: This embodiment solves the timing interference problem between the fixed absolute action time of the cylinder and the uncertain operating speed of the punch press. The dynamic advance angle conversion program of the drive component 6 and the wedge-shaped inclined surface 91 of the unlocking rod 9 produce a significant electromechanical synergy. The algorithm adaptively converts the time difference into a dynamic angle advance by measuring the angular velocity in real time, ensuring that the force transmission pad 7 reaches the target safe positioning angle of the punch press. The force transmission pad 7 is positioned in advance under the tension state without heavy load interference, so when the unlocking rod 9 moves down with the unloading plate 3, its wedge-shaped inclined surface 91 can slide precisely and without resistance into the through groove 82 to complete the passive mechanical locking. This closed-loop coordination of control and mechanical timing avoids the occurrence of electronic control delays and mechanical interference collisions.

[0056] Example 7: Based on Example 6 above, position detection elements are provided at both ends of the drive component 6. The controller is used to execute the moving average time calibration logic.

[0057] In actual mass production in the workshop, the air pressure in the air supply system fluctuates dynamically due to the intermittent air consumption of other equipment, causing the actual reversing extension time of drive component 6 to deviate from the theoretical value. To eliminate this pneumatic hysteresis, the controller is calibrated using a sliding average time. During system initialization, the controller is preset with a static theoretical response time as a constant. The initial seed value. In the non-cut-off dry-running state of continuous stamping of progressive dies, the drive component 6 does not trigger scrap cutting, but the controller will periodically issue test commands. The clock module inside the controller records in real time the actual action time from the moment the trigger command is issued until the moment the force transmission pad 7 is fully in place and triggers the position detection element to output a level signal.

[0058] The controller continuously records the actual action time of multiple dry-fire states and calculates the average of these multiple actual action times, using this average as the dynamically updated response time constant. The dynamically updated version The original pre-stored value is overwritten in real time and directly provided as input data to the dynamic advance angle conversion program in Example 4. The calculation.

[0059] The control system determines that the progressive die is in a non-cut-off dry-run state using the following method: During continuous stamping operation of the press, the material detection sensor continuously outputs a material position signal to the controller; when the material detection sensor does not detect the scrap strip extending to the set length (or does not block the sensor beam), the controller's internal state machine determines that the current stroke is in a non-cut-off dry-run state. In this state, the drive assembly 6 does not perform the action of pushing the force transmission pad 7 into the bearing position, and the cutting punch 4 retracts upward; at the same time, the controller uses the timing gap of this normal dry-run stroke to periodically or intermittently issue test commands to record the actual action time from the issuance of the trigger command to the output level signal of the position detection elements on both sides of the drive assembly 6, thereby safely completing the sliding average time calibration without load interference.

[0060] The beneficial effects of the above technical solution are as follows: This embodiment solves the technical problem of drive component response time drift failure caused by unstable air supply pressure and mechanical wear. It utilizes a position detection element to obtain underlying real-time motion feedback, and combines this with a moving average filtering formula to correct and calibrate the response time reference in real time. This effectively filters out abnormal fluctuation data caused by instantaneous changes in the workshop's air supply, ensuring the dynamic angle of the trigger command issued by the control system is accurate. By constantly monitoring the actual wear and pressure conditions of the current gas path system, the system avoids angle calculation deviations caused by inaccurate time constants, thus ensuring the control accuracy of the entire system.

[0061] Example 8: Based on Example 6 above, the controller performs active unloading and unlocking: After the cutting punch 4 and the scrap die 5 cooperate to complete the scrap cutting, and the press slide passes the bottom dead center and rises upward, due to the strong elastic recovery clamping force of the high-strength steel plate being punched, the cutting punch 4 is subjected to severe clamping by the metal strip, resulting in high stripping resistance. This huge stripping resistance is transmitted upward, causing the contact surface between the force transmission pad 7 and the locking pin 8, which are in a locked state, to bear a high axial positive pressure, and the contact surface of the two is in a static friction locked state.

[0062] To prevent mechanical unlocking from causing the parts to seize up and become rough, the controller performs active unloading and unlocking. Before the unloading plate 3 is driven by the unloading elastic element to reset downward relative to the upper mold base 1 and before the unlocking rod 9 pushes back the locking pin 8, the controller calculates the timing in advance and sends a retraction command to the drive assembly 6 in advance.

[0063] According to the instruction, the controller controls the drive assembly 6 to pull the force transmission pad 7 backward. Due to the reverse pulling force of the drive assembly 6, a horizontal tangential force is applied to the groove contact surface, forcibly breaking the static friction state between the locking part 71 and the locking pin 8 contact surface, completing the first stage of active unloading. Subsequently, as the punch press slide continues to return and rise, the stripper plate 3 moves downward relative to the upper die holder 1 to reset, and the unlocking rod 9 moves downward accordingly. Its top wedge-shaped inclined surface 91 forcibly pushes back the locking pin 8 through mechanical pressure, so that it overcomes the preload of the locking elastic element 81 and completely exits the groove, completing the second stage of pure mechanical push-back unlocking.

[0064] The beneficial effects of the above technical solution are as follows: This embodiment solves the technical problem of the self-locking contact surface seizing due to high positive pressure during the return stroke of the mold under high stripping force, resulting in metal cold welding roughening and subsequent breakage of the unlocking rod 9. It employs a dual resistance-reducing unlocking mechanism: electronically controlled pre-shrinkage unloading of the control system and purely mechanical linkage unlocking of the mold structure. The pre-issued shrinkage command actively disrupts the static friction self-locking state using the transient kinetic energy of the drive component's reversal, thereby significantly reducing the vertical thrust required for the unlocking rod 9 during subsequent mechanical reset. This reduces the risk of unlocking jamming and mechanism breakage, and lowers downtime maintenance costs under high-frequency production.

[0065] Although embodiments of the present invention have been disclosed above, they are not limited to the applications listed in the specification and embodiments. They can be applied to various fields suitable for the present invention. Other modifications can be easily made by those skilled in the art. Therefore, without departing from the general concept defined by the claims and their equivalents, the present invention is not limited to the specific details and illustrations shown and described herein.

Claims

1. A progressive die with adaptive waste cutting function, characterized in that, It includes an upper die base (1), a lower die base (2), a stripper plate (3), a cutting punch (4) slidably disposed in the upper die base (1), and a scrap die (5) disposed on the lower die base (2); the stripper plate (3) is connected to the lower part of the upper die base (1) through a stripping elastic element, and generates a vertical relative displacement with the upper die base (1) during stamping; it also includes: The driving assembly (6) and the force transmission pad (7) driven by the driving assembly (6) to switch between the carrying position and the avoidance position, the force transmission pad (7) is located above the cutting punch (4) and is provided with a locking part (71). The locking pin (8) is slidably assembled in the upper mold base (1) and has a locking tendency to be inserted into the locking part (71) under the action of elastic pre-tightening force; The unlocking lever (9) is located on the unloading plate (3) and forms a linkage limit with the locking pin (8); When the unloading plate (3) and the upper mold base (1) move closer to each other, the unlocking rod (9) releases the blocking limit on the locking pin (8), and the locking pin (8) is inserted into the locking part (71) under the action of elastic pre-tightening force, locking the force transmission pad (7) in the bearing position.

2. A progressive die with adaptive waste cutting function according to claim 1, characterized in that, The locking part (71) is a groove formed at one end of the force transmission pad (7); The locking pin (8) is a horizontal locking pin that is horizontally slidably assembled in the upper mold base (1). One end of the pin faces the groove, and the other end abuts against a locking elastic element (81) that provides elastic pre-tightening force. The middle section of the locking pin (8) has a through groove (82) vertically opened. The unlocking rod (9) extends upward through the through groove (82) and has a blocking section processed on its upper part. Below the blocking section, there is a wedge-shaped inclined surface (91) that smoothly transitions to the blocking section. During relative displacement, the blocking section slides upward out of the through groove (82) so that the wedge-shaped inclined surface (91) releases the lateral obstruction of the locking pin (8).

3. A progressive die with adaptive waste cutting function according to claim 2, characterized in that, The end face of the locking pin (8) opposite the groove is formed as a wedge-shaped inclined surface, and the inner wall of the groove is machined with a mating inclined surface that fits against the wedge-shaped inclined surface; the contact surface formed by the fit between the wedge-shaped inclined surface and the mating inclined surface has a normal angle with the horizontal direction. The static friction coefficient of the contact surface material is ,and .

4. A progressive die with adaptive waste cutting function according to claim 2, characterized in that, The bottom of the unlocking rod (9) is provided with a T-shaped flange, and the unloading plate (3) is provided with a T-shaped groove that fits the T-shaped flange with a clearance. The two work together to form a radial floating structure so that the unlocking rod (9) only transmits vertical movement.

5. A progressive die with adaptive waste cutting function according to claim 2, characterized in that, The inside of the through groove (82) is provided with a pin, and a cam roller is rotatably connected through the pin. The surface of the unlocking rod (9) forms a rolling contact with the cam roller. A self-lubricating copper sleeve is fitted on the sliding outer circle surface of the locking pin (8).

6. A progressive die with adaptive waste cutting function according to claim 2, characterized in that, In the inner cavity of the upper mold base where the locking pin (8) is assembled, exhaust channels that connect to the outside of the mold base are provided at the blind end position near the locking part (71) and the tail position where the locking elastic element (81) is accommodated.

7. A progressive die with adaptive waste cutting function according to claim 1, characterized in that, The force transmission pad (7) has dovetail guide rails (72) machined on both sides, and the upper mold base (1) has a dovetail groove that matches the dovetail guide rails (72) inside; the force transmission pad (7) is provided with a limiting block with a buffer pad.

8. A progressive die with adaptive waste cutting function according to claim 1, characterized in that, It also includes a control system, which includes a material detection sensor located on the lower die holder side, an encoder for acquiring the real-time angle of the punch press spindle, and a controller electrically connected to the material detection sensor, the encoder and the drive assembly (6). The controller is equipped with a dynamic advance angle conversion module, which performs time derivative on the acquired real-time angle to obtain the real-time angular velocity of the punch press. ; Call the response time constant of the pre-stored driver component (6) Calculate the angle compensation amount According to the preset target safe positioning angle The dynamic trigger angle is calculated in reverse. ; When it is determined that scrap cutting needs to be performed, and the real-time angle of the punch press reaches the dynamic trigger angle. At that time, a trigger command is sent to the driving component (6).

9. A progressive die with adaptive waste cutting function according to claim 8, characterized in that, The drive component (6) is equipped with position detection elements at both ends, and the controller performs sliding average time calibration: in the non-cut-off dry-fire state, the actual action time from the issuance of the trigger command to the triggering of the position detection element is recorded; A moving average filtering algorithm is used to extract the average of the most recent N actual action times to dynamically update the response time constant. .

10. A progressive die with adaptive waste cutting function according to claim 8, characterized in that, The controller performs active unloading and unlocking: After the waste material is cut off and the punch passes the bottom dead center return stage, before the unloading plate (3) resets downward relative to the upper die seat (1) and the locking pin (8) is pushed back by the unlocking rod (9), a retraction command is sent to the drive assembly (6) in advance; by controlling the drive assembly (6) to pull the force transmission pad (7) backward, the static friction state between the locking part (71) and the locking pin (8) is broken, and then the unlocking rod (9) completes the mechanical push-back unlocking.

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