Plastic part injection molding equipment

Abstract

The invention discloses plastic part injection molding equipment, and relates to the field of injection molding equipment, the plastic part injection molding equipment comprises a charging barrel, a plunger and a hydraulic pump, a shifting block is fixed on the side surface of the plunger, a shifting fork corresponding to the shifting block is arranged on the outer side of the charging barrel, a carry circuit of the plunger is controlled through the shifting fork, and a heat exchange pipe is arranged on the side surface of the hydraulic pump. The side face of the plunger is connected with a shifting block through a U-shaped rod, a shifting fork is arranged outside the charging barrel in parallel and set according to the mold injection molding requirement, the shifting rod is triggered to pop up when the shifting block passes through the shifting rod setting position, and a drive circuit of the plunger is closed through a control switch. Due to the fact that the shifting fork is arranged independently outside the plunger, the abrasion and deformation problems of the plunger are not related, the accurate distance of the plunger is guaranteed, in addition, a heat exchange pipe is arranged in association with the carry position of the plunger to convey a cooling medium to the hydraulic pump, the temperature of hydraulic oil in the hydraulic pump is guaranteed, and various problems caused by the too high temperature of the hydraulic oil are avoided.

Description

Technical Field

[0001] The invention relates to injection molding equipment, and in particular to injection molding equipment for plastic parts. Background Art

[0002] The injection system of the prior art includes components such as a barrel, a screw (or a plunger), and a nozzle. The plastic raw material is heated and plasticized in the barrel, and the screw is pushed to compact, plasticize, and convey the plastic raw material. The plastic melt is injected into the mold through the nozzle to cool and form.

[0003] However, there are many problems with the existing injection system:

[0004] 1. After long-term use, the mechanical parts of the injection molding machine will cause the injection accuracy to decrease due to factors such as deformation, wear and fatigue of the injection screw;

[0005] 2. The hydraulic system will generate a lot of heat during operation. If the heat dissipation is poor, the oil temperature will be too high, the viscosity of the oil will decrease with the increase of temperature, leakage will increase, and the volumetric efficiency of the pump and the efficiency of the entire system will be significantly reduced; at the same time, it will accelerate the oxidation and deterioration of the oil and shorten the service life of the hydraulic oil; in addition, the high oil temperature will also cause the rubber seals to deform, accelerate aging and failure, and reduce the sealing performance.

[0006] To this end, those skilled in the art have proposed a plastic parts injection molding device to improve the structure of existing injection molding devices to help solve a series of problems caused by decreased precision of mechanical parts affecting injection molding and excessive temperature of the hydraulic system. Summary of the invention

[0007] In view of the deficiencies in the prior art, the present invention provides a plastic part injection molding device, in which a slide rail parallel to the plunger is fixed on the outside of the barrel, a shift fork is slidably arranged on the inside of the slide rail to associate with the movement of the plunger, and a distance measuring structure is independently provided outside the plunger, so that the accuracy will not change with the change of the plunger. The injection is stopped by triggering a preset shift fork, thereby avoiding accuracy problems caused by the plunger. In addition, a heat exchange tube is arranged on the outside of the hydraulic pump to associate with the movement of the plunger. As the plunger moves, the cooling medium is driven to be transported along the heat exchange tube, thereby more accurately controlling the heat exchange effect on the hydraulic pump.

[0008] To achieve the above objectives, the present invention is implemented through the following technical solutions: a plastic part injection molding device, including a barrel, a plunger and a hydraulic pump, a plunger is slidably arranged on the inner side of the barrel, a hydraulic pump is arranged on the end of the plunger, the material is heated in the barrel, and a thrust is applied to the plunger through the hydraulic pump, so that the plunger moves along the inner side of the barrel to inject the molten plastic into the mold.

[0009] In order to avoid the problem of injection accuracy error caused by deformation or wear of the plunger, a shift block is fixedly connected to the side of the plunger, a shift fork is provided on the outside of the barrel corresponding to the shift block, and a control switch is fixedly connected to the side of the shift block corresponding to the shift fork.

[0010] The shift fork is pre-arranged on the outside of the barrel according to the injection requirements of the injection mold, and the shift block advances together with the injection of the plunger. The advanced shift block presses against the triggering shift fork to pop out, and the popped-out shift fork applies pressure to the control switch, interrupting the control switch connection circuit from driving the plunger forward, thereby achieving precise stopping of the injection. Because the crossbeam standard is set independently of the plunger, the injection accuracy of the equipment will not be affected when the plunger is worn or deformed.

[0011] In addition, in order to solve the problem that the heat dissipation of the hydraulic oil in the existing hydraulic pump is poor, which easily leads to a decrease in oil viscosity and leakage, and affects the life of the seal, a heat exchange tube is sleeved on the outer side of the end of the hydraulic pump, and the heat exchange tube is connected to a water tank. A pressure rod is slidably arranged on the inner side of the water tank corresponding to the heat exchange tube, and the pressure rod is arranged in association with the advance distance of the plunger.

[0012] The pressure rod advances synchronously with the injection movement of the plunger, and the cooling medium in the water tank circulates through the heat exchange tube due to the pressurization of the pressure rod. Heat is exchanged between the cooling medium in the heat exchange tube and the hydraulic pump, taking away a large amount of heat energy in the hydraulic pump. At the same time, because the water tank is large in volume, the cooling medium carrying a large amount of heat energy cools down rapidly after entering the water tank, and the cooling medium passing through the heat exchange tube is replaced with the advancement of the plunger in the next cycle, thereby achieving a better cooling effect without affecting the normal use of the hydraulic pump.

[0013] Preferably, a U-shaped rod is fixedly connected to the side of the plunger, and the shift block is fixedly connected to one end of the U-shaped rod extending out of the barrel, so that the shift block can be synchronously advanced along with the plunger outside the barrel through the U-shaped rod.

[0014] A slide rail is fixed outside the barrel parallel to the plunger, and the shift fork is slidably arranged on the inner side of the slide rail. The shift fork moves along the slide rail and is positioned outside the barrel according to the capacity of the injection mold.

[0015] The control switch extends into the inner side of the slide rail corresponding to the shift fork setting. When the plunger moves forward, the shift block fixed to the side of the plunger by the U-shaped rod moves forward synchronously. At the same time, the control switch fixed to the shift block also moves forward together, so as to facilitate the triggering of the shift forks set at different positions.

[0016] Preferably, a slider is slidably arranged on the inner side of the slide rail, the shift fork is plugged into the side of the slider, a positioning screw is penetrated through the side of the slider, and the positioning screw presses against the side wall of the slide rail to realize the positioning of the slider.

[0017] After the mold is replaced, the volume of the mold moves the slider along the slide rail accordingly, and the positioning of the slider is achieved by pressing the positioning screw against the side wall of the slide rail. When the shift block moves to the slider position, the shift fork is triggered to pop out, and the popped-out shift fork applies a pressing action to the control switch, thereby cutting off the control circuit of the control switch to the plunger.

[0018] Preferably, one end of the shift fork extending into the inner side of the slider is fixedly connected to an end block, and a first spring is provided at the end of the shift fork to press against the inner wall of the slider through the end block. Under the elastic force of the first spring, the shift block will press forward against the side wall of the slider, and the shift fork limits the advance distance through the end block.

[0019] Preferably, a hinge rod is hingedly provided on the side of the slider, one end of the hinge rod extends into the inner side of the slider and a limiting protrusion is fixed to the end block corresponding to the end of the fork, and the hinge rod is pressed against and limited by the limiting protrusion. When the hinge rod is overlapped on the side of the fork, the limiting protrusion cooperates with the end block to limit the fork, so that the fork will not pop out under the elastic force of the first spring and is in a retracted state.

[0020] Preferably, the other end of the hinge rod passes through the side wall of the slider and extends corresponding to the shift block, and a second spring is provided between the hinge rod and the inner wall of the slider. When the plunger advances, the shift block gradually contacts the hinge rod, exerts a thrust on the hinge rod to overcome the elastic force of the second spring and rotate it, and the rotating hinge rod loses its limiting effect on the shift fork, causing the shift fork to pop out under the elastic force of the first spring, and the popped-out shift fork presses against the control switch above it, thereby cutting off the control circuit for the plunger advancement.

[0021] Preferably, a threaded barrel is fixedly connected to the side of the hinge rod, a tightening screw is threadedly sleeved on the inner side of the threaded barrel, the tightening screw passes through the side wall of the slider away from the hinge rod and is slidably connected thereto, and the second spring is sleeved on the side of the tightening screw.

[0022] The extension length of the tightening screw is adjusted by the threaded barrel, and the end of the tightening screw is limited by the slider, so that the extension length of the tightening screw relative to the threaded barrel can change the limiting accuracy of the hinge rod to the shift fork.

[0023] A fixing block is fixed to the side of the tightening screw, and the second spring is tightly sleeved through the fixing block. After the extension length of the adjusting screw relative to the threaded barrel changes, the elastic force of the second spring on the hinge rod is adjusted, thereby achieving the adjustment of the trigger force accuracy of the hinge rod, avoiding the problem that the shift block cannot sensitively trigger the hinge rod and affect the accuracy of the equipment.

[0024] Preferably, sleeves are symmetrically fixed on the sides of the water tank, and both ends of the heat exchange tube are respectively connected with the ends of the sleeves on both sides. A piston is fixedly connected to the corresponding sleeve on the side of the pressure rod. When the pressure rod moves to one side, the piston in the sleeve in the opposite direction leaves the sleeve range, and the cooling medium in the water tank enters the sleeve. As the pressure rod advances, the piston applies pressure to the cooling medium in the sleeve, so that the cooling medium is transported along the heat exchange tube. The cooling medium in transportation exchanges heat with the side wall of the hydraulic pump, taking away a large amount of heat energy in time, thereby ensuring the temperature of the hydraulic oil in the hydraulic pump.

[0025] Preferably, a turntable is provided on the inner side of the barrel and the water tank, a transmission belt is connected between the two turntables, gears are sleeved and fixed on the side of the turntable, and the plunger and the pressure rod are meshed and connected with the turntable through gears.

[0026] When the barrel advances, the turntable is driven to rotate through the meshing relationship with the gear, and the two turntables are synchronously driven by the transmission belt, and then the turntable drives the pressure rod to advance, so as to realize the flow of heat exchange medium synchronously driven by the movement of the plunger.

[0027] Preferably, the sides of the plunger and the pressure rod are fixedly connected with racks corresponding to the gears, and guide blocks and guide rods are correspondingly arranged between the water tank and the pressure rod. Under the action of the guide blocks and guide rods, the pressure rod is ensured to move smoothly in the water tank as the plunger moves.

[0028] The present invention discloses a plastic part injection molding device, which has the following beneficial effects:

[0029] 1. The plastic parts injection molding equipment connects the shift block through a U-shaped rod on the side of the plunger, and sets a shift fork in parallel outside the barrel. The shift fork is set according to the injection molding needs of the mold. When the shift block passes the setting position of the slider, the shift rod is triggered to pop out, and the driving circuit of the plunger is turned off by the control switch. Because the setting of the shift fork is independent of the plunger, it has nothing to do with the wear and deformation of the plunger, ensuring the accurate distance of the plunger. In addition, a heat exchange pipe is set in conjunction with the advance of the plunger to transport the cooling medium to the hydraulic pump, ensuring the temperature of the hydraulic oil in the hydraulic pump, and avoiding various problems caused by excessive hydraulic oil temperature.

[0030] 2. In the plastic parts injection molding equipment, the side of the plunger is connected to the shift block through a U-shaped rod, a slide rail is arranged parallel to the outside of the barrel, a slider is slidably arranged by the slide rail, a shift fork is arranged on the inner side of the slider through a first spring plug, and when the shift block passes through the slider, it contacts the hinge rod, the shift fork loses the limit of the hinge rod and pops out, and the popped-out shift fork touches the control switch, thereby realizing the driving circuit of closing the plunger at this position. The setting of the shift fork is completely independent of the barrel and the plunger, and will not cause precision errors due to wear and deformation of the plunger, thereby ensuring the injection molding precision of the injection molding equipment.

[0031] 3. In the plastic parts injection molding equipment, the shift fork is set by the first spring, and then the shift fork is limited by the hinge rod pressed by the second spring. One end of the hinged hinge rod contacts the shift block that moves synchronously with the plunger, so that the hinged hinge rod compresses the second spring to deflect. After the shift fork loses the limit of the hinge rod, it is bounced up by the first spring. In addition, the side surface of the hinge rod is threadedly connected to the tightening screw through the threaded barrel. The elastic force of the second spring can be adjusted by the tightening screw, so that the shift block is more sensitive to the triggering structure of the hinge rod, and there will be no excessive error affecting the injection molding accuracy.

[0032] 4. In the plastic parts injection molding equipment, the advancement of the plunger is driven by the rotation of the turntable driven by the gear. A transmission belt is set between the two turntables for transmission connection. The turntable drives the advancement of the pressure rod to realize the linkage and advancement distance of the cooling medium in the heat exchange tube. As the hydraulic pump drives the advancement of the plunger, the piston connected to the end of the pressure rod advances along the sleeve, and the cooling medium inside the sleeve is pressed into the heat exchange tube. The flowing cooling medium exchanges heat with the hydraulic pump, and the heat energy of the hydraulic oil is taken away in time, thereby ensuring that the temperature of the hydraulic pump does not exceed the safety range. BRIEF DESCRIPTION OF THE DRAWINGS

[0033] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0034] Figure 1 It is a schematic diagram of the overall structure of the present invention;

[0035] Figure 2 It is a schematic diagram of the installation and matching structure of the outer shift block and the shift fork of the hydraulic pump of the present invention;

[0036] Figure 3 This is a schematic diagram of the heat exchange structure of the present invention;

[0037] Figure 4 It is a schematic diagram of the connection structure between the shift block and the plunger of the present invention;

[0038] Figure 5 For the present invention Figure 4 A schematic diagram of the structure enlargement in the middle;

[0039] Figure 6 It is a schematic diagram of the installation structure of the shift fork on the inner side of the slider of the present invention;

[0040] Figure 7 It is a schematic diagram of the limiting structure of the hinge rod against the shift fork of the present invention;

[0041] Figure 8It is a schematic diagram of the linkage driving structure of the plunger and the pressure rod of the present invention.

[0042] In the figure: 1. barrel; 2. plunger; 3. hydraulic pump; 4. shift block; 5. shift fork; 6. control switch; 7. heat exchange tube; 8. water tank; 9. pressure rod; 10. U-shaped rod; 11. slide rail; 12. slider; 13. positioning screw; 14. end block; 15. first spring; 16. hinge rod; 17. limit convex block; 18. second spring; 19. threaded barrel; 20. tightening screw; 21. sleeve; 22. piston; 23. turntable; 24. transmission belt; 25. gear; 26. rack. DETAILED DESCRIPTION

[0043] In order to make the purpose, technical solutions and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention are clearly and completely described. Obviously, the described embodiments are part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0044] The embodiment of the present invention discloses a plastic part injection molding device;

[0045] According to the attached Figure 1 As shown, it comprises a barrel 1, a plunger 2 and a hydraulic pump 3. The plunger 2 is slidably arranged inside the barrel 1, and the hydraulic pump 3 is arranged at the end of the plunger 2.

[0046] The injection molding equipment of the prior art heats the raw material to a molten state in the barrel 1, and then applies thrust to the plunger 2 through the hydraulic pump 3, so that the plunger 2 moves along the barrel 1, and pushes the molten plastic in the barrel 1 into the mold for cooling and molding.

[0047] However, the injection molding equipment in the prior art has problems such as deformation, wear and fatigue of the plunger 2 as it is used. These factors will cause errors in the advancement of the plunger 2, and ultimately lead to a decrease in injection accuracy, affecting the quality of the injection molded product. In addition, the hydraulic system of the existing injection molding equipment will generate a large amount of heat during operation, and usually this closed hydraulic system has a poor heat dissipation effect. If the heat dissipation is poor, the oil temperature in the hydraulic system will be too high, the viscosity of the oil will decrease with the increase in temperature, leakage will increase, and the volumetric efficiency of the pump and the efficiency of the entire system will be significantly reduced; at the same time, it will also accelerate the oxidation and deterioration of the oil and shorten the service life of the hydraulic oil; in addition, excessively high oil temperature will also cause the rubber seal to deform, accelerate aging and failure, and reduce the sealing performance. Therefore, those skilled in the art have proposed improvement plans for the existing equipment.

[0048] According to the attached Figure 2As shown, a shift block 4 is fixedly connected to the side of the plunger 2 , a shift fork 5 is provided on the outer side of the barrel 1 corresponding to the shift block 4 , and a control switch 6 is fixedly connected to the side of the shift block 4 corresponding to the shift fork 5 .

[0049] The shift fork 5 is pre-arranged at a certain interval outside the barrel 1 according to the volume of the injection mold. The shift block 4 advances along with the plunger 2 during injection molding. The shift block 4 triggers the shift fork 5 to pop out, and the pressing control switch 6 interrupts the advance drive of the plunger 2.

[0050] Because the shift block 4 is independently arranged from the plunger 2, the accuracy will not be affected by the deformation and wear of the plunger 2. When the plunger 2 advances, the shift block 4 and the plunger 2 advance synchronously. The fixed points of the shift block 4 and the plunger 2 are close to the end position and are less affected by the plunger 2. When the advance distance is certain, the shift block 4 encounters the shift fork 5, which is triggered to pop up and exerts pressure on the control switch 6 to disconnect the advance control circuit of the plunger 2, thereby temporarily terminating the advance injection molding of the plunger 2. The injection molding accuracy is less affected by the plunger 2.

[0051] According to the attached Figure 3 As shown, a heat exchange tube 7 is sleeved on the outer side of the end of the hydraulic pump 3, and the heat exchange tube 7 is connected to a water tank 8. A large amount of cooling medium is stored in the water tank 8, which is transported in large quantities to the hydraulic pump 3 through the heat exchange tube 7, thereby ensuring timely heat exchange and ensuring the temperature range of the hydraulic pump 3.

[0052] A pressure rod 9 is slidably arranged on the inner side of the water tank 8 corresponding to the heat exchange tube 7. The pressure rod 9 is arranged in association with the advancement distance of the plunger 2. The pressure rod 9 advances synchronously with the injection molding of the plunger 2. The liquid water in the water tank 8 is pressurized by the pressure rod 9 and circulates through the heat exchange tube 7 to exchange heat with the hydraulic pump 3. At the same time, it can ensure that there is no excessive energy loss in the heat exchange structure.

[0053] When the plunger 2 advances due to the pressure of the hydraulic pump 3, the heat energy generated by the flow of hydraulic oil in the corresponding hydraulic pump 3 is certain. As the heat energy is generated, the cooling medium in the water tank 8 flows through the hydraulic pump 3 through the heat exchange pipe 7, which can ensure the heat exchange effect of the newly generated heat energy at the hydraulic pump 3.

[0054] According to the attached Figure 4 As shown, a U-shaped rod 10 is fixedly connected to the side of the plunger 2, and the shift block 4 is fixedly connected to one end of the U-shaped rod 10 extending out of the barrel 1. The U-shaped rod 10 can ensure that the shift block 4 extends to the outside of the barrel 1 and is synchronously advanced with the advancement of the plunger 2, thereby ensuring the association with the advancement of the plunger 2, thereby ensuring the control of the injection molding accuracy.

[0055] A slide rail 11 is fixed outside the barrel 1 parallel to the plunger 2 , the shift fork 5 is slidably arranged on the inner side of the slide rail 11 , and the control switch 6 extends into the inner side of the slide rail 11 and is arranged corresponding to the shift fork 5 .

[0056] The shift fork 5 moves to a suitable position along the slide rail 11 for positioning according to the volume of the desired injection mold. In addition, the control switch 6 is fixed to the shift block 4 to ensure that the control switch 6 always moves synchronously with the shift block 4 as it moves forward.

[0057] According to the attached Figure 5 As shown, a slider 12 is slidably arranged on the inner side of the slide rail 11, and the fork 5 is plugged into the side of the slider 12. The internal fork 5 can be positioned and installed at an appropriate position through the slider 12. In addition, the plugged fork 5 can be triggered to pop up when the shift block 4 passes by, and a force is applied to the control switch 6 to interrupt the advance drive of the plunger 2.

[0058] A positioning screw 13 is provided through the side of the slider 12, and the positioning screw 13 presses against the side wall of the slide rail 11 to position the slider 12. After the slider 12 is moved to the set position, the positioning screw 13 is screwed to make the positioning screw 13 move relative to the slider 12, and then press against the side wall of the slide rail 11 to position the slider 12.

[0059] According to the attached Figure 6 and attached Figure 7 As shown, one end of the shift fork 5 extending into the inner side of the slider 12 is fixedly connected to an end block 14, and a first spring 15 is provided at the end of the shift fork 5 through the end block 14 and the inner wall of the slider 12 to ensure that the shift fork 5 will not escape from the limit of the slider 12 when it is activated by the elastic force of the first spring 15 under the action of the end block 14. In addition, the shift fork 5 pressed by the first spring 15 can bounce up after being triggered, and act on the control switch 6 to disconnect the carry control circuit of the plunger 2.

[0060] A hinge rod 16 is hingedly provided on the side of the slider 12, and one end of the hinge rod 16 extends into the inner side of the slider 12 and is fixed with a limiting protrusion 17 corresponding to the end block 14 at the end of the fork 5. The hinge rod 16 is pressed against the fork 5 by the limiting protrusion 17. When the hinge rod 16 is pressed against the side of the fork 5 by the force, the end block 14 at the end of the fork 5 can be limited by the limiting protrusion 17 to ensure that the fork 5 will not pop out under the elastic force of the first spring 15, thereby maintaining the power storage state. When the shift block 4 passes by and contacts the hinge rod 16, the pop-up trigger of the fork 5 pressed against by the first spring 15 is completed.

[0061] According to the attached Figure 7 and attached Figure 8 As shown, the other end of the hinge rod 16 passes through the side wall of the slider 12 and extends corresponding to the shift block 4, and the deflection direction of the hinge rod 16 is consistent with the advancement direction of the shift block 4, avoiding obstacles to the continued advancement of the shift block 4.

[0062] A second spring 18 is provided between the hinge rod 16 and the inner wall of the slider 12 , and a pressing force is applied to the hinge rod 16 by the second spring 18 , thereby ensuring that the hinge rod 16 has a pressing and limiting effect on the shift fork 5 .

[0063] A threaded tube 19 is fixedly connected to the side of the hinge rod 16, and a tightening screw 20 is threadedly sleeved on the inner side of the threaded tube 19. The end of the tightening screw 20 away from the hinge rod 16 passes through the side wall of the slider 12 and is slidably connected thereto. The second spring 18 is sleeved on the side of the tightening screw 20.

[0064] The tightening screw 20 threadedly connected to the threaded tube 19 can adjust the extension length relative to the hinge rod 16 through the action of the thread. A fixing block is fixedly connected to the side of the tightening screw 20 corresponding to the second spring 18. The second spring 18 is tightly sleeved on the side of the tightening screw 20 through the fixing block. As the extension length of the tightening screw 20 relative to the hinge rod 16 changes, the distance between the fixing block on the side of the tightening screw 20 and the inner wall of the slider 12 changes, thereby changing the elastic force applied by the second spring 18 to the tightening screw 20, thereby realizing the adjustment of the limiting force applied by the hinge rod 16 to the shift fork 5, ensuring the triggering accuracy of the shift block 4 on the hinge rod 16, and avoiding the problem of triggering but not firing.

[0065] The sides of the water tank 8 are symmetrically fixed with sleeves 21, and the two ends of the heat exchange tube 7 are respectively connected with the ends of the sleeves 21 on both sides. The side of the pressure rod 9 is fixedly connected with a piston 22 corresponding to the sleeve 21. When the pressure rod 9 moves forward, the piston 22 on one side moves forward, exerting pressure on the cooling medium in the sleeve 21, so that the cooling medium is transported along the heat exchange tube 7.

[0066] The cooling medium in the water tank 8 is much more than that in the heat exchange tube 7, and the matching states of the pistons 22 and the sleeves 21 on both sides of the pressure rod 9 are staggered, so that when the pressure rod 9 moves to one side, one piston 22 moves inside the corresponding sleeve 21, while the other piston 22 is separated from the corresponding sleeve 21. The cooling medium in the heat exchange tube 7 circulates and enters the water tank 8 for mixing to achieve rapid cooling.

[0067] A turntable 23 is disposed inside the barrel 1 and the water tank 8 , a transmission belt 24 is connected between the two turntables 23 , a gear 25 is sleeved and fixed on the side of the turntable 23 , and the plunger 2 and the pressure rod 9 are meshed and connected with the turntable 23 through the gear 25 .

[0068] When the plunger 2 advances, a turntable 23 is driven to rotate through the meshing action of the gear 25, and the two turntables 23 are transmitted through the transmission belt 24, and then the turntable 23 synchronously drives the pressure rod 9 to advance, thereby realizing the associated advancement of the pressure rod 9 and the plunger 2.

[0069] The sides of the plunger 2 and the pressure rod 9 are fixedly connected with a rack 26 corresponding to the gear 25, and a guide block and a guide rod are correspondingly arranged between the water tank 8 and the pressure rod 9. Under the action of the guide block and the guide rod, the cooperation between the piston 22 and the sleeve 21 on both sides of the pressure rod 9 is ensured.

[0070] In the plastic parts injection molding equipment, a shift block 4 is connected to the side of the plunger 2 through a U-shaped rod 10, and a shift fork 5 is arranged in parallel outside the barrel 1. The shift fork 5 is set according to the injection molding requirements of the mold. When the shift block 4 passes through the setting position of the slider 12, the shift fork 5 is triggered to pop out, and the driving circuit of the plunger 2 is turned off by controlling the switch 6. Because the setting of the shift fork 5 is independent of the plunger 2, it has nothing to do with the wear and deformation of the plunger 2, and the accurate distance of the plunger 2 is guaranteed. In addition, a heat exchange tube 7 is also arranged in connection with the advance of the plunger 2 to transport the cooling medium to the hydraulic pump 3, so as to ensure the temperature of the hydraulic oil in the hydraulic pump 3 and avoid various problems caused by excessively high hydraulic oil temperature.

[0071] Furthermore, the side of the plunger 2 is connected to the shift block 4 through a U-shaped rod 10, and a slide rail 11 is arranged parallel to the outside of the barrel 1, and a slider 12 is slidably arranged through the slide rail 11. The shift fork 5 is inserted and arranged on the inner side of the slider 12 through a first spring 15. When the shift block 4 passes through the slider 12, it contacts the hinge rod 16, and the shift fork 5 loses the limiting effect of the hinge rod 16 and pops out. The popped-out shift fork 5 touches the control switch 6, thereby realizing the closing of the driving circuit of the plunger 2 at this position. The setting of the shift fork 5 is completely independent of the barrel 1 and the plunger 2, and will not cause precision errors due to wear and deformation of the plunger 2, thereby ensuring the injection molding accuracy of the injection molding equipment.

[0072] Furthermore, the shift fork 5 is set tightly by the first spring 15, and then the hinge rod 16 is tightened by the second spring 18 to limit the shift fork 5. One end of the hinged hinge rod 16 contacts the shift block 4 that advances synchronously with the plunger 2, so that the hinged hinge rod 16 compresses the second spring 18 and deflects it. After the shift fork 5 loses the limiting effect of the hinge rod 16, it is bounced up by the first spring 15. In addition, the side surface of the hinge rod 16 is threadedly connected to the tightening screw 20 through the threaded cylinder 19. The elastic force of the second spring 18 can be adjusted by the tightening screw 20, so that the triggering structure of the shift block 4 to the hinge rod 16 is more sensitive, and there will be no excessive error that affects the injection molding accuracy.

[0073] Furthermore, the advancement of the plunger 2 drives the turntable 23 to rotate through the gear 25, and a transmission belt 24 is set between the two turntables 23 for transmission connection, and then the turntable 23 drives the advancement of the pressure rod 9, so as to realize the linkage and associated advancement distance of the cooling medium in the heat exchange tube 7. As the hydraulic pump 3 drives the advancement of the plunger 2, the piston 22 connected to the end of the pressure rod 9 advances along the sleeve 21, and presses the cooling medium inside the sleeve 21 into the heat exchange tube 7. The flowing cooling medium exchanges heat with the hydraulic pump 3, and promptly takes away the heat energy of the hydraulic oil, thereby ensuring that the temperature of the hydraulic pump 3 does not exceed a safe range.

[0074] The above shows and describes the basic principles and main features of the present invention and the advantages of the present invention. It should be understood by those skilled in the art that the present invention is not limited to the above embodiments. The above embodiments and descriptions are only for explaining the principles of the present invention. Without departing from the spirit and scope of the present invention, the present invention may have various changes and improvements, which fall within the scope of the present invention to be protected. The scope of protection of the present invention is defined by the attached claims and their equivalents.

Claims

1. A plastic injection molding device, comprising a barrel (1), a plunger (2) and a hydraulic pump (3), wherein the barrel (1) is slidably provided with a plunger (2), and the end of the plunger (2) is provided with a hydraulic pump (3), characterized in that: A shift block (4) is fixedly connected to the side of the plunger (2), a shift fork (5) is provided on the outer side of the barrel (1) corresponding to the shift block (4), and a control switch (6) is fixedly connected to the side of the shift block (4) corresponding to the shift fork (5); The shift fork (5) is arranged outside the barrel (1) according to the injection molding requirements, the shift block (4) is advanced together with the plunger (2) during injection molding, the shift block (4) triggers the shift fork (5) to pop out, and pressing the control switch (6) interrupts the advancement drive of the plunger (2); A heat exchange tube (7) is sleeved on the outer side of the end of the hydraulic pump (3), the heat exchange tube (7) is connected to a water tank (8), a pressure rod (9) is slidably arranged on the inner side of the water tank (8) corresponding to the heat exchange tube (7), and the pressure rod (9) is arranged in association with the advance distance of the plunger (2); The pressure rod (9) is moved synchronously with the injection molding of the plunger (2), and the liquid water in the water tank (8) is pressurized by the pressure rod (9) and circulates through the heat exchange tube (7) to exchange heat with the hydraulic pump (3).

2. The plastic part injection molding equipment according to claim 1, characterized in that: A U-shaped rod (10) is fixedly connected to the side of the plunger (2); the shift block (4) is fixedly connected to one end of the U-shaped rod (10) extending out of the barrel (1); a slide rail (11) is fixed outside the barrel (1) parallel to the plunger (2); the shift fork (5) is slidably arranged on the inner side of the slide rail (11); and the control switch (6) extends into the inner side of the slide rail (11) and is arranged corresponding to the shift fork (5).

3. The plastic part injection molding equipment according to claim 2, characterized in that: A slider (12) is slidably arranged on the inner side of the slide rail (11), the shift fork (5) is plugged into the side of the slider (12), a positioning screw (13) is penetrated through the side of the slider (12), and the positioning screw (13) is pressed against the side wall of the slide rail (11) to realize the positioning of the slider (12).

4. The plastic part injection molding equipment according to claim 3, characterized in that: One end of the shift fork (5) extending into the inner side of the slider (12) is fixedly connected to an end block (14), and a first spring (15) is provided at the end of the shift fork (5) so as to be tightly pressed between the end block (14) and the inner wall of the slider (12).

5. The plastic part injection molding equipment according to claim 4, characterized in that: A hinge rod (16) is hingedly provided on the side of the slider (12), one end of the hinge rod (16) extends into the inner side of the slider (12) and is fixed with a limiting protrusion (17) corresponding to the end block (14) at the end of the shift fork (5), and the hinge rod (16) is pressed against the shift fork (5) to limit the position through the limiting protrusion (17).

6. The plastic part injection molding device according to claim 5, characterized in that: The other end of the hinge rod (16) passes through the side wall of the slider (12) and extends corresponding to the shift block (4), and a second spring (18) is arranged between the hinge rod (16) and the inner wall of the slider (12).

7. The plastic part injection molding device according to claim 6, characterized in that: A threaded tube (19) is fixedly connected to the side of the hinge rod (16), and a tightening screw (20) is threadedly sleeved on the inner side of the threaded tube (19). The end of the tightening screw (20) away from the hinge rod (16) passes through the side wall of the slider (12) and is slidably connected thereto. The second spring (18) is sleeved on the side of the tightening screw (20).

8. The plastic part injection molding equipment according to claim 1, characterized in that: The side of the water tank (8) is symmetrically fixed with a sleeve (21), the two ends of the heat exchange tube (7) are respectively connected to the ends of the sleeves (21) on both sides, and the side of the pressure rod (9) is fixedly connected with a piston (22) corresponding to the sleeve (21).

9. The plastic part injection molding device according to claim 8, characterized in that: A rotating disk (23) is disposed inside the barrel (1) and the water tank (8), a transmission belt (24) is connected between the two rotating disks (23), a gear (25) is sleeved and fixed on the side of the rotating disk (23), and the plunger (2) and the pressure rod (9) are meshed and connected with the rotating disk (23) via the gear (25).

10. The plastic part injection molding equipment according to claim 9, characterized in that: The side surfaces of the plunger (2) and the pressure rod (9) are fixedly connected with a rack (26) corresponding to the gear (25), and a guide block and a guide rod are correspondingly arranged between the water tank (8) and the pressure rod (9).

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