Plastic nut thread twisting demolding mechanism

Abstract

The application discloses a plastic nut thread twisting demolding mechanism and relates to the technical field of mechanical engineering. Two rotation-stopping assemblies, a demolding assembly and a bottom plate are arranged on the top of the bottom plate. The rotation-stopping force in the plastic nut thread twisting demolding stage is dynamically and adaptively regulated by means of the rotation-stopping assembly. The mechanism is different from the passive constraint mode of the traditional rigid convex block frame spring needle. The rotation-stopping process is more accurate and controllable. Firstly, the temperature-driven deformation of the SMA elastic substrate and the elastic potential energy compensation of the copper electrode spring sheet are utilized to realize the step-by-step output of the force value. In combination with the real-time feedback of the pressure sensor and the temperature sensor, the contact pressure can be dynamically adjusted. In this way, the dynamic stress demand of the plastic nut caused by material shrinkage and size deviation can be targetedly matched. In the demolding rotation process, the plastic nut neither deviates from the rotation nor is damaged due to excessive extrusion. Compared with the traditional fixed force value constraint mode, the mechanism is more adaptable.

Description

TECHNICAL FIELD

[0001] The application relates to the technical field of mechanical engineering, in particular to a plastic nut thread stripping demolding mechanism. BACKGROUND

[0002] The plastic nut thread stripping demolding mechanism is a special demolding device for a plastic nut plastic part with internal threads in an injection mold, and the core function is to solve the meshing relationship between the internal threads of the plastic nut and the thread core of the mold after the plastic nut is formed, so that the plastic part and the mold are separated by rotating the thread.

[0003] In the traditional plastic nut thread stripping demolding mechanism, a combination of a rigid protrusion and a spring ejector pin is used to achieve rotation stopping, wherein the protrusion is embedded in the side hole of the plastic part, and the spring provides a pre-tightening force, so that the rotation stopping force only depends on the spring force, and the contact form of the combination of the rigid protrusion and the spring ejector pin is point-line contact, which can cause fatigue failure of the spring after long-term use. At the same time, the contact between the protrusion and the plastic part is a hard collision, and the protrusion is rigidly fixed, which causes a large instantaneous impact force when demolding at high speed, and cannot adapt to the size deviation of the plastic part caused by injection shrinkage, thereby causing the thread or side hole of the thin-walled nut to crack, and also causing serious deformation of the plastic part.

[0004] Therefore, we propose a plastic nut thread stripping demolding mechanism to solve the problems mentioned above. SUMMARY

[0005] The application aims to provide a plastic nut thread stripping demolding mechanism, which dynamically and adaptively regulates the rotation stopping force during the plastic nut thread stripping demolding stage through the synergistic effect of the double-arched SMA elastic substrate assembly and the quick-change interface assembly, which is different from the passive constraint mode of the traditional rigid protrusion frame spring ejector pin, so that the rotation stopping process is more accurate and controllable. First, the temperature-driven deformation of the SMA plate and the elastic potential energy compensation of the copper substrate are used to realize the stepwise output of the force value, and the real-time feedback of the pressure sensor and the temperature sensor can dynamically adjust the contact pressure. In this way, the dynamic stress demand of the plastic nut caused by material shrinkage and size deviation can be matched.

[0006] To achieve the above-mentioned purpose, the application provides the following technical scheme: a plastic nut thread stripping demolding mechanism, two rotation stopping assemblies, a demolding assembly and a bottom plate, the top of the bottom plate is respectively provided with two rotation stopping assemblies and a demolding assembly, the demolding assembly is arranged at the bottom of the two rotation stopping assemblies, and the two rotation stopping assemblies are symmetrically placed.

[0007] The rotation-stopping assembly comprises a copper alloy substrate, an insulating silica gel layer and an SMA elastic substrate, the copper alloy substrate is used for structural support and deformation constraint, the insulating silica gel layer is used for electrical insulation and vibration buffering, the SMA elastic substrate adopts a double-arch structure and is used for active rotation stopping, and the copper alloy substrate and the insulating silica gel layer are fully attached to the double-arch structure of the SMA elastic substrate.

[0008] The demolding assembly comprises a servo motor and a Hall sensor, the servo motor is used for providing demolding power, and the Hall sensor is used for real-time monitoring of the rotation state.

[0009] Preferably, the top of the bottom plate is connected with a movable mold, and the top of the movable mold is provided with a fixed mold.

[0010] Preferably, the rotation-stopping assembly further comprises a guide groove, a core and a cavity, guide rails are movably arranged between the inner surface walls of the guide groove, the guide groove is arranged on one side of the outer wall of the movable mold, and two hole grooves are arranged on the inner surface walls of the guide groove.

[0011] Preferably, a hole is arranged on one side of the inner wall of each of the two hole grooves, a first spring is connected to one side of the inner wall of each of the two holes, a limiting ring is elastically connected to one side of the outer wall of each of the two first springs, a positioning pin is connected to one side of the outer wall of each of the two limiting rings, two first fixing seats are connected to one side of the outer wall of the guide rail, a second spring is elastically connected to one side of the inner wall of each of the two first fixing seats, an elastic plate is elastically connected to one side of the outer wall of each of the two second springs, and the elastic plate and the two positioning pins are connected in a plug-in manner.

[0012] Preferably, one side of the outer wall of the guide rail is connected to one side of the outer wall of the copper alloy substrate, one side of the outer wall of the copper alloy substrate is attached to one side of the outer wall of the insulating silica gel layer, one side of the outer wall of the insulating silica gel layer is attached to one side of the outer wall of the SMA elastic substrate, a temperature sensor is arranged on one side of the outer wall of the copper alloy substrate, and a pressure sensor is arranged on one side of the outer wall of the SMA elastic substrate.

[0013] Preferably, copper electrode springs are connected to the bottom and the top of the inner surface walls of the guide groove, and the two copper electrode springs are used for providing electrical continuity and adapting to the micro-displacement of the SMA elastic substrate, four positioning holes are arranged on one side of the outer wall of the SMA elastic substrate, two engaging pieces are bolted to one side of the outer wall of the guide rail, two ceramic limiting columns are connected to one side of the outer wall of each of the two engaging pieces, and the four ceramic limiting columns are used for limiting the maximum deformation of the SMA elastic substrate, and a displacement sensor is mounted on one side of the inner wall of the guide groove, and the displacement sensor is used for real-time monitoring of the micro-displacement.

[0014] Preferably, one side of the outer wall of the guide rail is connected with a second fixing base, the inner wall of the second fixing base is connected with a piezoelectric ceramic sheet, and the piezoelectric ceramic sheet is used for providing micro-displacement compensation and shortening the action distance of the SMA.

[0015] Preferably, the demolding assembly further comprises a fixed base, one side of the outer wall of the fixed base is connected with one side of the outer wall of the moving die, one side of the outer wall of the servo motor is connected with a bolt of the fixed base, and the power output end of the servo motor is rotatably connected with a driving gear.

[0016] Preferably, one side of the outer wall of the first driven gear is rotatably connected with a second driven gear, the power output end of the second driven gear is rotatably connected with a belt, the inner surface of the belt is rotatably connected with a third driven gear, and one side of the outer wall of the third driven gear is rotatably connected with a fourth driven gear.

[0017] Preferably, a connecting sleeve is arranged between the inner surfaces of the fourth driven gear, the outer surface of the connecting sleeve is bolted to one side of the outer wall of the Hall sensor, a tooth rod is arranged on the top of the connecting sleeve, and the bottom of the tooth rod is connected with the bottom of the core.

[0018] Compared with the prior art, the beneficial effects of the present application are:

[0019] In the present application, the rotation stopping force in the tooth stripping demolding stage of the plastic nut is dynamically self-adaptively regulated by means of the rotation stopping assembly, which is different from the passive constraint mode of the traditional rigid protruding block frame spring needle, so that the rotation stopping process is more accurate and controllable. Firstly, the temperature-driven deformation of the SMA elastic substrate and the elastic potential energy compensation of the copper electrode spring sheet are utilized to realize the stepwise output of the force value, and the real-time feedback of the pressure sensor and the temperature sensor can dynamically adjust the contact pressure. In this way, the dynamic stress demand generated by the material shrinkage and size deviation of the plastic nut can be targetedly matched, so that the plastic nut does not rotate deviate in the demolding rotation process, and damage of the plastic part caused by excessive extrusion is avoided. Compared with the traditional fixed force value constraint mode, the present application is more adaptable. BRIEF DESCRIPTION OF DRAWINGS

[0020] Figure 1 It is a front view of the structure of the plastic nut tooth stripping demolding mechanism of the present application;

[0021] Figure 2 It is a sectional view of the structure of the plastic nut tooth stripping demolding mechanism of the present application;

[0022] Figure 3 It is a position relationship diagram of the rotation stopping assembly and the demolding assembly in the plastic nut tooth stripping demolding mechanism of the present application.

[0023] Figure 4 It is a structure perspective view of the stop rotation assembly in the plastic nut thread twisting and demolding mechanism of the application;

[0024] Figure 5 It is a structure schematic view of the installation position of the ceramic limiting column, copper electrode elastic sheet and displacement sensor in the plastic nut thread twisting and demolding mechanism of the application;

[0025] Figure 6 It is a structure schematic view of the installation position of the first fixed seat, second spring and elastic plate in the plastic nut thread twisting and demolding mechanism of the application;

[0026] Figure 7 It is a structure schematic view of the installation position of the copper alloy base plate, insulating silica gel layer and SMA elastic base plate in the plastic nut thread twisting and demolding mechanism of the application;

[0027] Figure 8 It is a structure schematic view of the installation position of the copper alloy base plate and temperature sensor in the plastic nut thread twisting and demolding mechanism of the application;

[0028] Figure 9 It is a structure perspective view of the demolding assembly in the plastic nut thread twisting and demolding mechanism of the application;

[0029] Figure 10 It is a structure schematic view of the installation position of the driving gear, first driven gear and second driven gear in the plastic nut thread twisting and demolding mechanism of the application;

[0030] Figure 11 It is Figure 10 It is an enlarged perspective view of structure A.

[0031] In the figure: 100, base plate; 200, movable mold; 300, fixed mold; 400, stop rotation assembly; 401, guide groove; 402, guide rail; 403, hole groove; 404, first spring; 405, limiting ring; 406, positioning pin; 407, first fixed seat; 408, second spring; 409, elastic plate; 410, copper alloy base plate; 411, insulating silica gel layer; 412, SMA elastic base plate; 413, pressure sensor; 414, temperature sensor; 415, joint; 416, ceramic limiting column; 417, copper electrode elastic sheet; 418, displacement sensor; 419, core; 420, cavity; 421, second fixed seat; 422, piezoelectric ceramic sheet; 500, demolding assembly; 501, fixed base; 502, servo motor; 503, driving gear; 504, first driven gear; 505, second driven gear; 506, belt; 507, third driven gear; 508, fourth driven gear; 509, connecting sleeve; 510, Hall sensor; 511, toothed rod. DETAILED DESCRIPTION

[0032] The technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the drawings in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, rather than all the embodiments. Based on the embodiments in the present application, all other embodiments obtained by a person of ordinary skill in the art without creative work fall within the protection scope of the present application.

[0033] In the embodiment, the rigid protrusion and the spring needle are combined to achieve rotation stopping, the protrusion is embedded in the side hole of the plastic part, and the spring provides pre-tightening force, so that the rotation stopping force only depends on the spring force, and the contact form of the combination of the rigid protrusion and the spring needle is point-line contact, which can cause fatigue failure of the spring after long-term use. In addition, the contact between the protrusion and the plastic part is hard collision, and the protrusion is rigidly fixed, which can cause large instantaneous impact force during high-speed demolding, and cannot adapt to the size deviation of the plastic part caused by injection molding shrinkage, thereby causing cracking of the threads or side holes of the thin-walled nut, and causing serious deformation of the plastic part.

[0034] The embodiment is completed to solve the problem of the prior art, and the rotation stopping force of the plastic nut thread demolding stage is dynamically self-adaptively regulated by means of the rotation stopping assembly 400, which is different from the passive constraint mode of the traditional rigid protrusion frame spring needle, so that the rotation stopping process is more accurate and controllable. Firstly, the temperature-driven deformation of the SMA elastic substrate 412 and the elastic potential compensation of the copper electrode spring 417 are used to realize the stepwise output of the force value, and the real-time feedback of the pressure sensor 413 and the temperature sensor 414 can dynamically adjust the contact pressure. In this way, the dynamic stress demand of the plastic nut caused by material shrinkage and size deviation can be matched, so that the plastic nut can neither rotate deviate nor be damaged by excessive extrusion during demolding and rotation. Compared with the traditional fixed force value constraint mode, the embodiment has better adaptability.

[0035] Please refer to Figures 1-2 The embodiment discloses a plastic nut thread demolding mechanism, two rotation stopping assemblies 400, a demolding assembly 500, and a bottom plate 100. The top of the bottom plate 100 is respectively provided with the two rotation stopping assemblies 400 and the demolding assembly 500. The demolding assembly 500 is arranged at the bottom of the two rotation stopping assemblies 400, and the two rotation stopping assemblies 400 are symmetrically arranged.

[0036] The top of the bottom plate 100 is connected with a movable mold 200, and the top of the movable mold 200 is provided with a fixed mold 300.

[0037] In use, first, the movable mold 200 and the fixed mold 300 are determined to be fully fixed, and then the movable mold 200 and the fixed mold 300 are closed, at this time, the molten plastic fills between the core 419 and the cavity 420, at this time, the movable mold 200 and the fixed mold 300 are in a locked state to avoid the size deviation of the plastic part, and when the plastic part is formed, the mold is opened, at this time, the core 419 is driven to move synchronously by the movable mold 200 moving downward, the core 419 drives the formed plastic part to separate from the cavity 420, at this time, the mold opening in-place sensor installed beside the guide column of the fixed mold 300 is used, at this time, after the control system receives the mold opening in-place signal of the mold opening in-place sensor, the piezoelectric ceramic sheet 422 is immediately started, the piezoelectric ceramic sheet 422 triggers the inverse piezoelectric effect, at this time, the piezoelectric ceramic sheet 422 will be elongated along the direction of the guide rail 402, prompting the guide rail 402 to displace along the guide groove 401 to the direction of the core 419, then the control system controls the servo motor 502 to be energized and started, the servo motor 502 drives the driving gear 503 to rotate at a preset speed, and the power is transmitted to the tooth bar 511 through multi-stage gear transmission, at this time, the tooth bar 511 rotates synchronously with the fourth driven gear 508, at this time, the external threads of the core 419 and the internal threads of the plastic part produce relative movement and gradually separate, at this time, the control system synchronously energizes the SMA elastic substrate 412, the nickel-titanium alloy is heated to 80-100℃, thereby triggering the shape memory effect of the SMA elastic substrate 412 to gradually flatten from a double-arch shape and form a plane, the plastic part is prevented from rotating with the tooth bar 511 by friction, thereby completing the demolding work.

[0038] According to Figures 1-8 As shown in the figure, the rotation stopping assembly 400 includes a copper alloy substrate 410, an insulating silica gel layer 411, and an SMA elastic substrate 412, the copper alloy substrate 410 is used for structural support and deformation constraint, the insulating silica gel layer 411 is used for electrical insulation and vibration buffering, the SMA elastic substrate 412 adopts a double-arch structure and is used for active rotation stopping, and the copper alloy substrate 410 and the insulating silica gel layer 411 fully adhere to the double-arch structure of the SMA elastic substrate 412.

[0039] The rotation stopping assembly 400 further includes a guide groove 401, a core 419, and a cavity 420, the guide rail 402 is movably inserted between the inner surface walls of the guide groove 401, and the guide groove 401 is opened on one side of the outer wall of the movable mold 200, two hole grooves 403 are opened on the inner surface walls of the guide groove 401.

[0040] The inner wall side of the two hole grooves 403 is provided with a hole, the inner wall side of the two holes is connected with a first spring 404, the outer wall side of the two first springs 404 is elastically connected with a limiting ring 405, the outer wall side of the two limiting rings 405 is connected with a positioning pin 406, the outer wall side of the guide rail 402 is connected with two first fixed bases 407, the inner wall side of the two first fixed bases 407 is elastically connected with a second spring 408, the outer wall side of the two second springs 408 is elastically connected with an elastic plate 409, and the elastic plate 409 and the two positioning pins 406 are connected in insertion.

[0041] The outer wall side of the guide rail 402 is connected with the outer wall side of the copper alloy substrate 410, the outer wall side of the copper alloy substrate 410 is connected with the outer wall side of the insulating silica gel layer 411, the outer wall side of the insulating silica gel layer 411 is connected with the outer wall side of the SMA elastic substrate 412 in adhesion, the outer wall side of the copper alloy substrate 410 is provided with a temperature sensor 414, and the outer wall side of the SMA elastic substrate 412 is provided with a pressure sensor 413.

[0042] The inner surface wall bottom and top of the guide groove 401 are connected with copper electrode elastic sheets 417, the two copper electrode elastic sheets 417 are used to provide electrical continuity and adapt to the micro displacement of the SMA elastic substrate 412, the outer wall side of the SMA elastic substrate 412 is provided with four positioning holes, the outer wall side of the guide rail 402 is bolted with two engaging pieces 415, the outer wall side of the two engaging pieces 415 is connected with two ceramic limiting columns 416, and the four ceramic limiting columns 416 are used to limit the maximum deformation of the SMA elastic substrate 412, and the inner wall side of the guide groove 401 is provided with a displacement sensor 418, and the displacement sensor 418 is used to monitor the micro displacement in real time.

[0043] The outer wall side of the guide rail 402 is connected with a second fixed base 421, the inner wall side of the second fixed base 421 is connected with a piezoelectric ceramic sheet 422, and the piezoelectric ceramic sheet 422 is used to provide micro displacement compensation and shorten the SMA action distance, the bottom of the core 419 is connected with the top of the moving die 200, the top of the cavity 420 is connected with the bottom of the fixed die 300, and the cavity 420 is movably sleeved on the outer surface of the core 419.

[0044] In use, by presetting the above components, a complete rotation-stopping assembly 400 is formed. During the mold closing stage, the guide rail 402 in the rotation-stopping assembly 400 is fixed by the positioning pin 406 in the guide groove 401 in cooperation with the elastic plate 409. The positioning pin 406 is pressed into the clamping groove of the elastic plate 409 under the action of the first spring 404, and the elastic plate 409 is further supported by the pre-tightening force of the second spring 408, so as to ensure that the guide rail 402 does not shake in the guide groove 401. At this time, the copper alloy substrate 410, the insulating silica gel layer 411 and the SMA elastic substrate 412 maintain a natural double-arch shape, and an initial gap of 1-1.2 mm is reserved with the inner wall of the cavity 420. During the injection molding stage, the movable mold 200 and the fixed mold 300 are locked. At this time, the cavity 420 is filled with molten plastic and bears high pressure. When the injection molding is completed and the mold needs to be opened, the movable mold 200 is lowered to drive the mold core 419 and the plastic part to move synchronously. When the movable mold 200 is lowered to the preset stroke, the control system immediately starts the piezoelectric ceramic sheet 422. By using the inverse piezoelectric effect generated by the piezoelectric ceramic sheet 422, the piezoelectric ceramic sheet 422 is elongated by 0.3-0.5 mm along the length direction of the guide rail 402, and the guide rail 402 is pushed to move slightly along the guide groove 401 towards the mold core 419. At this time, the cooperation of the positioning pin 406 and the elastic plate 409 will not hinder this slight sliding. At this time, the displacement sensor 418 monitors the slight displacement in real time. When the preset value is reached, a compensation completion signal is fed back to the control system, and then the demolding stage is entered. By driving the jaw lever 511 to rotate by using the servo motor 502, the control system supplies power to the SMA elastic substrate 412 through the copper electrode spring 417. The SMA elastic substrate 412 made of nickel-titanium alloy material is heated to a temperature of 80-100°C under the action of the current, so as to trigger the shape memory effect. At this time, the SMA elastic substrate 412 gradually flattens from the double-arch shape. The deformation force generated by the SMA elastic substrate 412 is transmitted to the copper alloy substrate 410 through the insulating silica gel layer 411. Subsequently, the SMA elastic substrate 412 is fully attached to the side wall of the plastic part. At this time, the pressure sensor 413 monitors the contact force in real time, and the temperature sensor 414 monitors the temperature of the SMA elastic substrate 412 to ensure that it works stably within the phase transition temperature range. If the SMA elastic substrate 412 deforms excessively, the ceramic limiting column 416 will rigidly contact to limit the maximum strain of the SMA elastic substrate 412, so as to avoid permanent deformation of the SMA elastic substrate 412. When the demolding is completed, the temperature of the SMA elastic substrate 412 decreases to room temperature. Under the action of the elasticity of the SMA elastic substrate 412 and the auxiliary resilience of the copper alloy substrate 410, the SMA elastic substrate 412 recovers from the flat state to the double-arch shape, so as to separate from the side wall of the plastic part. Subsequently, the plastic part is taken away, so as to complete the entire demolding work.

[0045] Throughout the process, the temperature-driven deformation of the SMA elastic substrate 412 and the elastic compensation of the copper electrode spring 417 form a stepped force output. Combined with the real-time feedback of the sensor, it can not only accurately constrain the plastic part from rotating with the toothed bar 511, but also dynamically adapt to the dimensional deviation of the plastic part caused by shrinkage, thus completely solving the problem that traditional rigid anti-rotation structures are prone to cracking or deformation of the plastic part.

[0046] Example 2, according to Figures 1-2 as well as Figures 9-11 As shown, the demolding assembly 500 includes a servo motor 502 and a Hall sensor 510. The servo motor 502 is used to provide demolding power, and the Hall sensor 510 is used to monitor the rotation status in real time.

[0047] The demolding assembly 500 also includes a fixed base 501, and one side of the outer wall of the fixed base 501 is connected to one side of the outer wall of the moving mold 200. One side of the outer wall of the servo motor 502 is bolted to the fixed base 501. The power output end of the servo motor 502 is rotatably connected to the drive gear 503, and one side of the outer wall of the drive gear 503 is meshed with the first driven gear 504.

[0048] The first driven gear 504 is meshed with a second driven gear 505 on one side of its outer wall. The power output end of the second driven gear 505 is rotatably connected to a belt 506. The inner surface of the belt 506 is rotatably connected to a third driven gear 507. The outer wall of the third driven gear 507 is meshed with a fourth driven gear 508.

[0049] A connecting sleeve 509 is inserted between the inner surfaces of the fourth driven gear 508. The outer surface of the connecting sleeve 509 is bolted to one side of the outer wall of the Hall sensor 510. A toothed rod 511 is inserted into the top of the connecting sleeve 509. The top of the toothed rod 511 is connected to the bottom of the core 419.

[0050] In use, through the above components, the complete stripping assembly 500 is composed. First, in the mold closing stage, the stripping assembly 500 is closed with the movable mold 200 and the fixed mold 300 to enter the standby state. When entering the injection stage, the movable mold 200 and the fixed mold 300 are locked, and the cavity 420 is filled with molten plastic. At this time, the servo motor 502 receives the mold locking signal of the control system, the built-in brake device is started and the output shaft is locked. At this time, the tooth bar 511 and the core 419 remain in a rigid fixed state. When the mold opening stage, the movable mold 200 is lowered to drive the entire stripping assembly 500 to descend synchronously, and then the core 419 is separated from the cavity 420 with the movable mold 200, and the plastic part is preliminarily separated from the fixed mold 300. When the control system receives the piezoelectric compensation completion signal fed back by the rotation stopping assembly 400, the control system immediately sends an instruction to the servo motor 502, and then starts the servo motor 502 and makes the servo motor 502 rotate at a preset speed. At this time, the driving gear 503 rotates, and the driving gear 503 and the first driven gear 504 are engaged, and the power is transmitted to the first driven gear 504, the second driven gear 505, the belt 506, the third driven gear 507, and the fourth driven gear 508 in turn. Finally, the tooth bar 511 is driven to rotate synchronously through the connecting sleeve 509. In the process of rotation, the outer thread of the core 419 and the inner thread of the plastic part produce relative helical motion, and the plastic part is gradually unscrewed from the core 419. At the same time, the Hall sensor 510 monitors the rotation state of the connecting sleeve 509 in real time, and feeds back the rotation speed data to the control system in real time, so as to ensure that the rotation angle of the tooth bar 511 matches the length of the plastic part thread. The built-in torque sensor of the servo motor 502 will monitor the output torque in real time. When the plastic part is stuck, the load increases suddenly, and the machine is stopped immediately, so as to avoid damage to the tooth bar 511 and the gears caused by overload. Through multi-stage gear transmission, the load of single gear is dispersed, the wear of gear surface is reduced, the servo motor 502 is accurately controlled to avoid stripping impact load, so as to prolong the service life of the mold. The combination of gears and belts 506 in the working process of the stripping assembly 500 not only ensures the power transmission efficiency, but also reduces the high-frequency vibration through the flexible buffer of the belt 506.

[0051] More specific solutions, according to the rotation stopping assembly 400 in embodiment one and the stripping assembly 500 in embodiment two, the final result embodied by the combination of the two is:

[0052] The demolding assembly 500 is driven by the servo motor 502 to realize precise control of the rotation angle of the tooth bar 511 through multi-stage gear and belt 506 transmission, thereby ensuring the stability of the spiral separation of the internal thread of the plastic part and the external thread of the core 419. The rotation-stopping assembly 400 relies on the temperature-driven deformation of the SMA elastic substrate 412 and the micro-displacement compensation of the piezoelectric ceramic sheet 422 to form an effective dynamic rotation-stopping force. When the plastic part shrinks due to injection molding, the pressure sensor 413 feeds back the contact force in real time, and the control system adjusts the power of the SMA elastic substrate 412 to make the rotation-stopping force adapt to the change of the plastic part shape. This avoids the overpressure cracking caused by the fixed force of the traditional rigid bump, and solves the rotation-stopping failure caused by the attenuation of the force of the spring needle. The cooperation between the rotation-stopping assembly 400 and the demolding assembly 500 significantly reduces the risk of failure. The torque monitoring of the servo motor 502 in the demolding assembly 500 and the pressure monitoring of the pressure sensor 413 in the rotation-stopping assembly 400 form a double overload protection mechanism, which successfully avoids the damage of the gear or the plastic part when the tooth bar 511 is stuck. In addition, the ceramic limiting column 416 and the copper alloy substrate 410 limit the maximum deformation of the SMA elastic substrate 412, and cooperate with the elastic conductive design of the copper electrode spring 417 to ensure the structural stability of the entire assembly in subsequent long-term use, solving the frequent maintenance problem caused by fatigue of the traditional spring needle.

[0053] Although the present application has been described in detail with reference to the foregoing embodiments, those skilled in the art can modify the technical solutions described in the foregoing embodiments or make equivalent replacements to some technical features, and any modification, equivalent replacement, improvement, etc. made within the spirit and principles of the present application shall be included in the protection scope of the present application.

Claims

1. A plastic nut thread twisting demolding mechanism, characterized by: Two rotation stopping assemblies (400), a demolding assembly (500), and a bottom plate (100), the top of the bottom plate (100) is respectively provided with two rotation stopping assemblies (400) and a demolding assembly (500), the demolding assembly (500) is arranged at the bottom of the two rotation stopping assemblies (400), and the two demolding assemblies (500) are symmetrically arranged; The rotation stopping assembly (400) comprises a copper alloy substrate (410), an insulating silica gel layer (411), and an SMA elastic substrate (412), the copper alloy substrate (410) is used for structural support and deformation constraint, the insulating silica gel layer (411) is used for electrical insulation and vibration buffering, and the SMA elastic substrate (412) adopts a double-arch structure and is used for active rotation stopping, and the copper alloy substrate (410) and the insulating silica gel layer (411) are fully attached to the double-arch structure of the SMA elastic substrate (412); The rotation stopping assembly (400) further comprises a guide groove (401), a core (419), and a cavity (420), guide rails (402) are movably arranged between the inner walls of the guide groove (401), and the guide groove (401) is arranged on one side of the outer wall of the movable die (200), and two hole grooves (403) are arranged on the inner walls of the guide groove (401); Holes are arranged on one side of the inner walls of the two hole grooves (403), first springs (404) are connected to one side of the inner walls of the two holes, limit rings (405) are elastically connected to one side of the outer walls of the two first springs (404), positioning pins (406) are connected to one side of the outer walls of the two limit rings (405), first fixed seats (407) are connected to one side of the outer wall of the guide rail (402), second springs (408) are elastically connected to one side of the inner walls of the two first fixed seats (407), elastic plates (409) are elastically connected to one side of the outer walls of the two second springs (408), and the elastic plates (409) and the two positioning pins (406) are connected in insertion; One side of the outer wall of the guide rail (402) and one side of the outer wall of the copper alloy substrate (410) are connected, one side of the outer wall of the copper alloy substrate (410) and one side of the outer wall of the insulating silica gel layer (411) are attached and connected, one side of the outer wall of the insulating silica gel layer (411) and one side of the outer wall of the SMA elastic substrate (412) are attached and connected, a temperature sensor (414) is arranged on one side of the outer wall of the copper alloy substrate (410), and a pressure sensor (413) is arranged on one side of the outer wall of the SMA elastic substrate (412). The inner wall bottom and top of the guide groove (401) are connected with copper electrode elastic sheets (417), and the two copper electrode elastic sheets (417) are used for providing electrically conductive continuity and adapting to the micro displacement of the SMA elastic substrate (412), one side of the outer wall of the SMA elastic substrate (412) is provided with four positioning holes, one side of the outer wall of the guide rail (402) is bolted with two engaging pieces (415), and one side of the outer wall of the two engaging pieces (415) is connected with two ceramic limiting columns (416), and the four ceramic limiting columns (416) are used for limiting the maximum deformation of the SMA elastic substrate (412), and the inner wall of the guide groove (401) is provided with a displacement sensor (418), and the displacement sensor (418) is used for real-time monitoring of the micro displacement. One side of the outer wall of the guide rail (402) is connected with a second fixing seat (421), one side of the inner wall of the second fixing seat (421) is connected with a piezoelectric ceramic sheet (422), and the piezoelectric ceramic sheet (422) is used for providing micro displacement compensation and shortening the SMA action distance, the bottom of the core (419) and the top of the moving die (200) are connected, and the top of the cavity (420) and the bottom of the fixed die (300) are connected, and the cavity (420) is movably sleeved on the outer surface of the core (419). The demolding assembly (500) comprises a servo motor (502) and a Hall sensor (510), the servo motor (502) is used for providing demolding power, and the Hall sensor (510) is used for real-time monitoring of the rotating state.

2. The plastic nut thread tapping and demolding mechanism according to claim 1, characterized in that: The top of the bottom plate (100) is connected with a moving die (200), and the top of the moving die (200) is provided with a fixed die (300).

3. The plastic nut thread twisting demolding mechanism according to claim 2, characterized in that: The demolding assembly (500) further comprises a fixed base (501), and one side of the outer wall of the fixed base (501) and one side of the outer wall of the moving die (200) are connected, one side of the outer wall of the servo motor (502) is bolted with the fixed base (501), the power output end of the servo motor (502) is rotatably connected with a driving gear (503), and one side of the outer wall of the driving gear (503) is meshed with a first driven gear (504).

4. The plastic nut thread twisting demolding mechanism according to claim 3, characterized in that: One side of the outer wall of the first driven gear (504) is meshed with a second driven gear (505), the power output end of the second driven gear (505) is rotatably connected with a belt (506), the inner surface of the belt (506) is rotatably connected with a third driven gear (507), and one side of the outer wall of the third driven gear (507) is meshed with a fourth driven gear (508).

5. The plastic nut thread twisting demolding mechanism according to claim 4, characterized in that: The connecting sleeves (509) are inserted between the inner surfaces of the fourth driven gears (508), the outer surface of the connecting sleeves (509) is bolted with one side of the outer wall of the Hall sensor (510), the top of the connecting sleeves (509) is inserted with a tooth bar (511), and the top of the tooth bar (511) is connected with the bottom of the core (419).

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