Multi-section pressure fitting plastic barrel injection molding device

Abstract

The invention provides a multi-section pressure fitting plastic barrel injection molding device which comprises an injection module, the injection module comprises a supporting seat, an oil pump and a gun barrel, a sliding seat is arranged on a base, the supporting seat is in sliding connection with the sliding seat, the oil pump and the gun barrel are installed on the supporting seat, and an injection molding screw is arranged in the gun barrel; an adjusting cylinder is arranged at one end of the gun barrel, an adjusting ring is arranged on the injection molding screw and divides an inner cavity of the adjusting cylinder into a propelling cavity and a retreating cavity, and the propelling cavity and the retreating cavity both communicate with the oil pump; a control valve, a pressure adjusting piece and an electromagnetic valve are arranged at one end of the gun barrel, the control valve comprises a valve body and a valve element, and the pressure adjusting piece comprises a shell, a cam and a gear set. A driving motor is arranged on the supporting seat and is in transmission connection with the injection molding screw rod through a gear set; one end of the valve element is located in the valve body, the other end of the valve element is located in the shell, the cam sleeves the injection molding screw, and a roller is arranged at the end, located in the shell, of the valve element and makes contact with the cam. The device can dynamically adjust the pressure according to the melt filling progress.

Description

Technical Field

[0001] This invention relates to the field of injection molding equipment technology, and more specifically, to a multi-stage pressure bonding injection molding device for plastic barrels. Background Technology

[0002] In the injection molding production of plastic buckets, traditional equipment lacks pressure regulation and oil flow stabilization structures, which makes it impossible to dynamically adjust the injection pressure according to the filling progress of the molten material in the mold cavity. When the molten material fills different parts, the pressure remains uniform and cannot adapt to the molding requirements of each part. At the same time, the internal oil flow of traditional equipment is prone to turbulence, resulting in fluctuating hydraulic pressure. Since the advancement speed of the injection screw depends entirely on hydraulic drive, the unstable pressure directly causes uneven filling speed of the molten material, resulting in missing threads at the bucket mouth, large deviations in bucket wall thickness, and shrinkage at the bottom of the bucket. Summary of the Invention

[0003] To address the aforementioned technical problems, this invention provides a multi-stage pressure bonding injection molding device for plastic barrels, thereby solving the technical problem in the prior art where traditional devices lack pressure control, resulting in the inability to dynamically adjust the injection pressure according to the filling progress of the molten material in the mold cavity.

[0004] The purpose and effectiveness of the multi-stage pressure bonding injection molding device for plastic barrels of the present invention are achieved by the following specific technical means: This invention provides a multi-stage pressure bonding injection molding device for plastic barrels, including a base, on which a molding module and an injection module are provided; the injection module includes a support seat, an oil pump and a barrel, a slide seat is provided on the base, the support seat and the slide seat are slidably connected, the oil pump and the barrel are mounted on the support seat, and an injection screw is provided inside the barrel; The barrel is equipped with an adjusting cylinder at one end, and the injection screw is equipped with an adjusting ring. The adjusting ring divides the inner cavity of the adjusting cylinder into a propulsion cavity and a retraction cavity. Both the propulsion cavity and the retraction cavity are connected to the oil pump. The barrel is provided with a control valve, a pressure regulating component, and a solenoid valve at one end. The control valve includes a valve body and a valve core. The pressure regulating component includes a housing, a cam, and a gear set. The support base is equipped with a drive motor, which is connected to the injection screw via the gear set. One end of the valve core is located inside the valve body, and the other end of the valve core is located inside the housing. The cam is sleeved on the injection screw. A roller is provided at one end of the valve core located in the housing, and the roller contacts the cam.

[0005] As a preferred embodiment, the valve body is provided with two sets of baffles, which divide the valve body cavity into a buffer chamber, a control chamber, and a pressurization chamber. The buffer chamber is located at the outlet end of the control valve, the pressurization chamber is located at the inlet end of the control valve, and the control chamber is located between the buffer chamber and the pressurization chamber.

[0006] In a preferred embodiment, the control chamber has three sets of throttling orifices at one end near the pressurization chamber, and one end of the valve core is located inside the control chamber and has two sets of through holes. The control chamber is connected to the pressurization chamber through the throttling orifices. The pressurizing chamber is L-shaped, and a feedback hole is provided inside the pressurizing chamber. An electric push rod is installed on the valve body. The movable rod of the electric push rod passes through the feedback hole. A pressure regulating spring is provided on the movable rod of the electric push rod, and a plug is provided at the end of the pressure regulating spring away from the movable rod of the electric push rod. A piston block is slidably disposed within the buffer chamber, and a balance channel is provided in the buffer chamber. The buffer chamber is connected to the opening end of the control valve through the balance channel.

[0007] As a preferred embodiment, the pressure regulating spring is a variable diameter helical structure, and the pressure regulating spring decreases linearly along the axial direction from the end near the electric push rod to the end near the plug; The feedback port is provided with a limiting ring at one end near the pressurization chamber, the plug is inserted into the limiting ring, and an integrally formed limiting platform is provided at one end inside the feedback port.

[0008] As a preferred embodiment, the valve body is provided with an adjustment hole and a check hole. The adjustment hole is located below the control cavity and communicates with the control cavity. A return spring is provided inside the adjustment hole. The check hole includes an execution channel, a drive channel, and an adjustment channel. A limit groove is formed on the adjustment hole. The adjustment hole is connected to the execution channel through the limit groove. The execution channel is connected to the drive channel through the adjustment channel. The drive channel is connected to the pressurization chamber. An execution piston is slidably disposed in the execution channel, a drive piston is disposed in the drive channel, a rotating shaft is disposed in the adjustment channel, and a connecting rod is rotatably disposed on the rotating shaft, with both ends of the connecting rod connected to the execution piston and the drive piston respectively; A pawl is rotatably provided in the limiting groove, and the pawl contacts the actuating piston. Multiple sets of retaining rings are provided on the valve core, and the pawl contacts one of the retaining rings.

[0009] As a preferred embodiment, the partition is provided with a rectifier channel, and multiple flow dividers are evenly distributed on the inner wall of the rectifier channel. A flow guide channel is formed between the flow dividers, and pits and protrusions are alternately arranged on the flow guide channel. A grid is provided at one end of the rectifier channel.

[0010] In a preferred embodiment, the piston block is provided with a guide hole, a damping hole, and a connecting hole. The guide hole and the connecting hole are perpendicularly connected to the damping hole. The damping hole passes through the piston block, and the connecting hole is connected to the balance channel.

[0011] In a preferred embodiment, a damping slide rod is provided inside the damping hole, and a sliding protrusion is provided on the damping slide rod. A guide rod is provided inside the guide hole, with one end of the guide rod contacting the sliding protrusion and the other end being provided with a magnetic ring. An adsorption block is provided on the inner wall of the buffer cavity, and the adsorption block is magnetically connected to the magnetic ring. A damping spring is provided at the end of the damping hole away from the control cavity. The damping spring is in contact with the damping slide rod. A flow channel is provided on the damping slide rod. The flow channel is T-shaped and is connected to the balance channel through the connecting hole.

[0012] As a preferred embodiment, the cam has a multi-segment stepped profile, and its outer periphery includes three sets of circular arc segments connected in sequence along the circumference and a transition slope connecting adjacent circular arc segments.

[0013] In a preferred embodiment, the injection screw includes a feeding section, a compression section, and a metering section connected in sequence, wherein the feeding section is provided with a rocket head, a guide sleeve, and a check ring; The feeding section is equipped with a feeding hopper, and the compression section is equipped with a heating ring.

[0014] Compared with the prior art, the present invention has the following beneficial effects: 1. This invention utilizes a multi-segment stepped profile cam and control valve to dynamically adjust the injection pressure based on the molten material filling progress, thus improving the accuracy of pressure control. The device can move the valve core by different arc segments of the cam, and switch between different pressure levels by controlling the opening and closing of the three sets of throttling orifices in the control chamber and the valve core through-holes. This adapts to the molding requirements of various parts of the barrel, including the opening, body, and bottom, avoiding molding defects caused by traditional single-pressure methods and improving the device's pressure adaptability to different parts.

[0015] 2. When using this device, the flow channel of the baffle and the damping structure of the piston block can stabilize the oil flow, making the hydraulic pressure inside the device more stable and improving the oil flow stabilization effect. Then, through the cooperation of the damping slide bar, magnetic ring and adsorption block, pressure fluctuations are further buffered, so that the injection screw advance speed is uniform, avoiding uneven filling of melt material, and improving the operational stability of the device and the molding quality of the barrel.

[0016] 3. This invention, through the design of a check hole and a variable-diameter pressure regulating spring, enables the device to prevent the valve core from shifting backward and adaptively adjust the pressure feedback, thereby improving the reliability of the device's pressure control. The device can limit the valve core's retraction through the cooperation of a pawl and a retaining ring, and the variable-diameter structure of the pressure regulating spring adapts to different pressure feedback requirements, thus avoiding sudden pressure drops or shifts. This results in a more stable pressure output and improves the device's ability to resist pressure fluctuations. Attached Figure Description

[0017] Figure 1 This is a schematic diagram of the assembly structure of the invention; Figure 2 This is a schematic diagram of the internal structure of the invention; Figure 3 yes Figure 2 Enlarged view of region a in the middle; Figure 4 This is a schematic diagram of the pressure regulating component and control valve of the invention; Figure 5 This is a schematic diagram of the internal structure of the pressure regulating component and control valve of the invention; Figure 6 This is a schematic diagram of the internal structure of the control valve of the invention; Figure 7 yes Figure 6 Enlarged view of region b in the middle; Figure 8 yes Figure 6 Enlarged view of region c in the middle; Figure 9 This is a schematic diagram of the internal structure of the control valve part of the invention; Figure 10 It should be Figure 9 Enlarged schematic diagram of region d in the middle; Figure 11 This is a schematic diagram of the disassembled structure of the control valve of the invention; Figure 12 yes Figure 11 Enlarged schematic diagram of region e in the middle; Figure 13 This is a schematic diagram of the disassembled structure of the pressure regulating component of the invention.

[0018] In the diagram, the correspondence between component names and their corresponding reference numerals is as follows: 101. Base; 102. Compression molding module; 103. Support base; 104. Oil pump; 105. Gun barrel; 106. Slide block; 1071. Feeding section; 1072. Compression section; 1073. Metering section; 1074. Rocket head; 1075. Guide sleeve; 1076. Check ring; 108. Adjusting cylinder; 1081. Propulsion chamber; 1082. Retraction chamber; 109. Adjusting ring; 111. Solenoid valve; 112. Feed hopper; 113. Heating ring; 201. Valve body; 202. Valve core; 203. Baffle; 204. Buffer chamber; 2041. Balance channel; 205. Control chamber; 206. Pressurization chamber; 207. Throttling orifice; 208. Feedback orifice; 209. Electric push rod; 211. Pressure adjusting spring; 212. Plug; 213. Piston block; 2 14. Limiting ring; 215. Limiting platform; 216. Adjusting hole; 217. Return spring; 218. Actuation channel; 219. Drive channel; 221. Adjustment channel; 222. Limiting groove; 223. Actuating piston; 224. Drive piston; 225. Rotating shaft; 226. Connecting rod; 227. Pawl; 228. Snap ring; 229. Rectifying channel; 231. Flow divider; 232. Guide channel; 233. Grid; 234. Guide hole; 235. Damping hole; 236. Connecting hole; 237. Damping slide bar; 2371. Sliding protrusion; 238. Guide rod; 239. Magnetic ring; 241. Adsorption block; 242. Damping spring; 301. Housing; 302. Cam; 303. Gear set; 304. Drive motor; 305. Roller. Detailed Implementation

[0019] The embodiments of the present invention will be described in further detail below with reference to the accompanying drawings and examples. The following examples are used to illustrate the technical solutions of the present invention, but should not be used to limit the scope of protection of the present invention.

[0020] Example

[0021] like Figures 1 to 13As shown, this invention provides a multi-stage pressure-bonded plastic barrel injection molding device, including a base 101, on which a molding module 102 and an injection module are mounted; the injection module includes a support base 103, an oil pump 104, and a barrel 105; a slide 106 is provided on the base 101, and the support base 103 and the slide 106 are slidably connected; the oil pump 104 and the barrel 105 are mounted on the support base 103, and an injection screw is provided inside the barrel 105; an adjusting cylinder 108 is provided at one end of the barrel 105, and an adjusting ring 109 is provided on the injection screw; the adjusting ring 109 divides the inner cavity of the adjusting cylinder 108 into a pushing chamber 1081 and a retraction chamber 1082, and the pushing... Both cavity 1081 and retraction cavity 1082 are connected to oil pump 104; one end of barrel 105 is provided with control valve, pressure regulating component and solenoid valve 111. Control valve includes valve body 201 and valve core 202. Pressure regulating component includes housing 301, cam 302 and gear set 303; support base 103 is provided with drive motor 304. Drive motor 304 is connected to injection screw through gear set 303; one end of valve core 202 is located in valve body 201 and the other end of valve core 202 is located in housing 301. Cam 302 is sleeved on injection screw. One end of valve core 202 located in housing 301 is provided with roller 305. Roller 305 is in contact with cam 302.

[0022] Specifically, the molding module 102 is used to close and lock the mold, providing a sealed cavity for the molding of the plastic barrel. The injection module, as the core execution unit, has a support base 103 that can slide along the slide block 106 to adjust the relative position of the barrel 105 and the molding module 102, ensuring that the injection port aligns with the mold inlet. After the drive motor 304 starts, it drives the injection screw in the barrel 105 to rotate through the gear set 303, realizing the conveying, melting, and plasticizing of the plastic raw material. At the same time, the oil pump 104 supplies oil to the regulating cylinder 108. When the oil pump 104 injects oil into the push chamber 1081 and discharges oil into the retraction chamber 1082, the regulating ring 109 pushes the injection screw forward to inject the molten material into the mold cavity; conversely, it drives the screw to retract to replenish the raw material.

[0023] The cam 302 rotates synchronously with the injection screw. Its multi-stage stepped profile pushes the valve core 202 to reciprocate within the valve body 201 via the roller 305, thereby changing the fit clearance between the valve core 202 and the throttling orifice 207 inside the control valve. Combined with the on / off control of the solenoid valve 111, the hydraulic pressure of the propulsion chamber 1081 can be dynamically adjusted to achieve multi-stage pressure switching and adapt to the molding requirements of different parts of the barrel.

[0024] The cam 302 and the gear set 303 are fixed inside the housing 301. The injection screw is provided with multiple sets of rotating rhombuses along the circular axis. The cam 302 and the gear set 303 are driven by the rotating rhombuses. The specific transmission method is a conventional method in this technical field and will not be described in detail.

[0025] Understandably, this device is used for injection molding production of plastic barrels. It can specifically solve the defects of traditional devices, such as missing threads at the barrel opening, large deviations in barrel wall thickness, and shrinkage at the barrel bottom, caused by single pressure control and disordered oil flow. Through multi-stage pressure bonding and stable hydraulic drive, it improves the molding accuracy, structural strength, and sealing performance of plastic barrels, making it suitable for industrial mass production needs.

[0026] like Figures 2 to 12 As shown, the valve body 201 is provided with two sets of partitions 203. The two sets of partitions 203 divide the inner cavity of the valve body 201 into a buffer chamber 204, a control chamber 205, and a pressurizing chamber 206. The buffer chamber 204 is located at the outlet end of the control valve, the pressurizing chamber 206 is located at the inlet end of the control valve, and the control chamber 205 is located between the buffer chamber 204 and the pressurizing chamber 206.

[0027] Specifically, two sets of partitions 203 are arranged in parallel intervals within the valve body 201, and are fixed to the valve body 201 by welding or bolts to form a sealed separation, ensuring that the buffer chamber 204, control chamber 205, and pressurization chamber 206 are independent and connected only through preset channels, avoiding oil cross-contamination that could affect the pressure regulation accuracy. The pressurization chamber 206, as the oil input end, is directly connected to the output pipeline of the oil pump 104, responsible for receiving high-pressure oil and initially stabilizing the pressure. The control chamber 205, as the core adjustment area, has connecting holes 236 on its wall corresponding to the pressurization chamber 206 and the buffer chamber 204. The flow cross-section of the orifice can be changed by the reciprocating movement of the valve core 202 to achieve step-wise adjustment of the oil pressure. The buffer chamber 204 is located at the oil output end and is connected to the push chamber 1081 / retract chamber 1082 of the regulating cylinder 108. It is used to absorb pressure pulses when oil flows out of the control chamber 205, preventing sudden pressure changes from causing unstable injection screw propulsion.

[0028] This three-chamber partition structure allows the oil to flow in an orderly manner within the valve body 201 through "pressurization-regulation-buffering": the high-pressure oil first enters the pressurization chamber 206 to establish a basic pressure, then enters the buffer chamber 204 after being regulated by the control chamber 205 to eliminate turbulence and pressure fluctuations, and finally delivers it to the regulating cylinder 108 at a stable pressure, providing a smooth hydraulic driving force for the injection molding process. This structurally solves the problems of pressure regulation lag and oil turbulence caused by the lack of chamber partitioning in traditional control valves.

[0029] The control chamber 205 has three sets of throttling orifices 207 at one end near the pressurizing chamber 206. One end of the valve core 202 is located inside the control chamber 205 and has two sets of through holes. The control chamber 205 is connected to the pressurizing chamber 206 through the throttling orifices 207. The pressurizing chamber 206 is L-shaped and has a feedback hole 208 inside. An electric push rod 209 is installed on the valve body 201. The movable rod of the electric push rod 209 passes through the feedback hole 208. A pressure regulating spring 211 is provided on the movable rod of the electric push rod 209. A plug 212 is provided at the end of the pressure regulating spring 211 away from the movable rod of the electric push rod 209. A piston block 213 is slidably provided in the buffer chamber 204. The buffer chamber 204 has a balance channel 2041 and is connected to the opening end of the control valve through the balance channel 2041.

[0030] Specifically, the three sets of throttling orifices 207 are arranged linearly along the wall of the control chamber 205 near the pressurization chamber 206, with the orifice diameter increasing sequentially along the oil flow direction. Different combinations of orifice diameters can be used to adjust the flow capacity at multiple levels. The end of the valve core 202 that extends into the control chamber 205 is fitted with the chamber wall with a clearance. The two sets of through holes on its surface can move axially with the valve core 202 and connect with the corresponding throttling orifices 207. When the valve core 202 moves to different positions, the through holes can connect with the 1-3 sets of throttling orifices 207 individually or simultaneously, thereby changing the oil supply flow from the pressurization chamber 206 to the control chamber 205, realizing the graded switching of injection pressure, and adapting to the filling needs of different parts of the barrel.

[0031] The L-shaped pressurizing chamber 206 achieves a "oil inlet-feedback" spatial layout through a bending structure: one end is connected to the oil pump 104 pipeline to receive high-pressure oil, and the feedback hole 208 at the other end is coaxially set with the electric push rod 209. The plug 212 fits against the outlet of the feedback hole 208 under the preload of the pressure regulating spring 211, forming a pressure feedback threshold. When the pressure in the pressurizing chamber 206 exceeds the preset value, the oil pushes the plug 212 to compress the pressure regulating spring 211. The pressure change is fed back in real time through the displacement of the plug 212. The electric push rod 209 can finely adjust the extension length of the movable rod according to the feedback signal and adjust the preload of the pressure regulating spring 211 to achieve dynamic pressure compensation.

[0032] The piston block 213 in the buffer chamber 204 slides and seals against the chamber wall. When the oil regulated by the control chamber 205 enters the buffer chamber 204, the oil pushes the piston block 213 to move. At the same time, the balance channel 2041 connects the buffer chamber 204 with the opening of the control valve. The oil pressure pulse is absorbed by the damping effect of the piston block 213. If the pressure in the buffer chamber 204 is too high, some oil can be discharged through the balance channel 2041 to avoid the sudden pressure rise causing the regulating cylinder 108 to become unstable. This ensures that the injection screw advances at a uniform speed and prevents overflow or material shortage during molten material filling.

[0033] The pressure regulating spring 211 has a variable diameter spiral structure. The pressure regulating spring 211 decreases linearly along the axial direction from the end near the movable rod of the electric push rod 209 to the end near the plug 212. The feedback hole 208 is provided with a limiting ring 214 at the end near the pressurization chamber 206. The plug 212 passes through the limiting ring 214 and is provided with an integrally formed limiting platform 215 at the end located inside the feedback hole 208.

[0034] Specifically, the variable diameter spiral structure of the pressure regulating spring 211 is achieved through a linear change in pitch—the pitch of the wire is smallest at the end near the movable rod of the electric push rod 209, gradually increasing towards the plug 212. This results in a gradient distribution of the spring's stiffness along the axial direction: the stiffness is high near the movable rod end, which can stably withstand the initial preload and prevent excessive deformation of the spring when the electric push rod 209 is finely adjusted; the stiffness is low near the plug 212 end, which can sensitively respond to pressure changes in the pressurization chamber 206. When the oil pushes the plug 212, the spring can provide feedback on pressure fluctuations through flexible deformation, which not only prevents spring breakage caused by sudden pressure rise, but also improves the sensitivity of pressure compensation, solving the problem of "fixed stiffness and lag in pressure feedback" in traditional constant diameter springs. The limiting ring 214 inside the feedback hole 208 is fixed to the hole wall by an interference fit. Its inner diameter is clearance-fitted with the outer diameter of the plug 212, which ensures that the plug 212 slides smoothly along the axial direction of the feedback hole 208 and prevents oil leakage from the gap. The limiting platform 215, which is integrally formed at one end of the plug 212, has a diameter larger than the inner diameter of the limiting ring 214, forming a mechanical limit. When the pressure in the pressurization chamber 206 is too high and the plug 212 moves towards the electric push rod 209, the limiting platform 215 will abut against the end face of the limiting ring 214, limiting the maximum displacement of the plug 212. This prevents the plug 212 from over-compressing the pressure regulating spring 211 and causing the spring to fail. At the same time, it prevents the plug 212 from detaching from the feedback hole 208 and causing a large amount of oil leakage, ensuring the stable operation of the pressure feedback structure and further improving the pressure regulation reliability of the control valve.

[0035] The valve body 201 has an adjustment hole 216 and a check hole. The adjustment hole 216 is located below the control cavity 205 and communicates with the control cavity 205. A return spring 217 is installed inside the adjustment hole 216. The check hole includes an execution channel 218, a drive channel 219, and an adjustment channel 221. A limit groove 222 is provided on the adjustment hole 216. The adjustment hole 216 communicates with the execution channel 218 through the limit groove 222. The execution channel 218 communicates with the drive channel 219 through the adjustment channel 221. The moving channel 219 is connected to the pressurizing chamber 206; the execution channel 218 is slidably provided with an execution piston 223, the drive channel 219 is provided with a drive piston 224, the adjusting channel 221 is provided with a rotating shaft 225, and a connecting rod 226 is rotatably provided on the rotating shaft 225. The two ends of the connecting rod 226 are respectively connected to the execution piston 223 and the drive piston 224; a pawl 227 is rotatably provided in the limiting groove 222. The pawl 227 contacts the execution piston 223. Multiple sets of retaining rings 228 are provided on the valve core 202. The pawl 227 contacts one of the retaining rings 228.

[0036] Specifically, one end of the return spring 217 abuts against the bottom of the adjustment hole 216, and the other end contacts the protruding end of the valve core 202 extending into the adjustment hole 216, always providing the valve core 202 with a preload towards the control chamber 205; when the cam 302 pushes the valve core 202 to move and adjust the pressure, the return spring 217 can drive the valve core 202 to return to its original position quickly, avoiding the valve core 202 from jamming and causing pressure adjustment lag, and ensuring the timeliness of pressure level switching.

[0037] The three channels of the check valve are arranged in a U-shape: the drive channel 219 is directly connected to the pressurization chamber 206, which can receive high-pressure oil and push the drive piston 224 to slide along the channel; the drive piston 224 drives the rotating shaft 225 to rotate through the connecting rod 226, which in turn pulls the execution piston 223 in the execution channel 218 to move synchronously, and the execution piston 223 is linked with the pawl 227 in the limiting groove 222; when the valve core 202 has a tendency to deviate in the reverse direction due to pressure fluctuation, the execution piston 223 pushes the pawl 227 to rotate around the inner wall of the limiting groove 222, so that the pawl 227 is engaged in the retaining ring 228 of the valve core 202, forming a mechanical check valve limit, preventing the valve core 202 from moving in the reverse direction and causing the throttling orifice 207 to be misaligned with the through hole, thus avoiding a sudden drop in pressure.

[0038] This synergistic structure of "reset spring 217 + check hole" ensures the reset accuracy of valve core 202 after adjustment through reset spring 217, and prevents valve core 202 from shifting by mechanical limit of check hole. It provides double protection for the positional stability of valve core 202 during pressure regulation, solves the pressure pulse problem caused by valve core 202 polarization in traditional control valves, and further improves the reliability of pressure control of the device.

[0039] The partition 203 has a rectifier channel 229. Multiple flow dividers 231 are evenly distributed on the inner wall of the rectifier channel 229. A flow guide channel 232 is formed between the flow dividers 231. The flow guide channel 232 is alternately provided with pits and protrusions. A grid 233 is provided at one end of the rectifier channel 229.

[0040] Specifically, the rectifying channel 229 on the baffle 203 is a through-hole structure. The multi-component flow dividers 231 are radially and uniformly distributed around the axis of the rectifying channel 229. The guide channel 232 formed between adjacent flow dividers 231 is a fan-shaped structure, and the cross-section of the channel gradually narrows from the inlet end to the outlet end. This can divide the turbulent oil entering the rectifying channel 229 into multiple orderly flow streams, avoiding the formation of turbulence due to oil collisions. At the same time, the alternating pits and protrusions on the inner wall of the guide channel 232 can further break the laminar boundary layer of the oil and weaken local eddies. The grid 233 at the outlet end of the rectifying channel 229 is made of metal, and the mesh is evenly arranged in regular hexagons. This can perform secondary filtration and flow stabilization on the oil that has been initially rectified by the guide channel 232, ultimately allowing the oil to enter the subsequent chamber in a stable laminar flow state, preventing pressure fluctuations caused by oil turbulence and ensuring the stability of the hydraulic drive.

[0041] The piston block 213 is provided with a guide hole 234, a damping hole 235 and a connecting hole 236. The guide hole 234 and the connecting hole 236 are perpendicular to the damping hole 235. The damping hole 235 passes through the piston block 213 and the connecting hole 236 is connected to the balance channel 2041.

[0042] Specifically, the piston block 213 has a cylindrical structure with a through damping hole 235 in its axial direction, serving as the main channel for oil flow; the guide hole 234 is opened radially along the piston block 213 and intersects the damping hole 235 perpendicularly in the middle of the channel, forming a "T" shaped intersection structure; the connecting hole 236 is also opened radially, located below the guide hole 234 and communicating with the damping hole 235, and the diameter of the connecting hole 236 is smaller than that of the damping hole 235, with one end communicating with the damping hole 235 and the other end extending to the outer wall of the piston block 213, sealingly connecting with the balance channel 2041 of the buffer chamber 204. This channel layout allows some of the oil to flow into the balance channel 2041 through the connecting hole 236 after entering the damping hole 235, achieving pressure balance. At the same time, the guide hole 234 provides installation and sliding space for the guide rod 238, ensuring that the guide rod 238 can act on the damping slide rod 237, and achieve damping adjustment through mechanical linkage, avoiding jamming or displacement when the piston block 213 moves, and improving the pressure buffering effect of the buffer chamber 204.

[0043] A damping slide rod 237 is provided inside the damping hole 235. A sliding protrusion 2371 is provided on the damping slide rod 237. A guide rod 238 is provided inside the guide hole 234. One end of the guide rod 238 contacts the sliding protrusion 2371, and the other end is provided with a magnetic ring 239. An adsorption block 241 is provided on the inner wall of the buffer cavity 204. The adsorption block 241 is magnetically connected to the magnetic ring 239. A damping spring 242 is provided at the end of the damping hole 235 away from the control cavity 205. The damping spring 242 contacts the damping slide rod 237. A flow channel is opened on the damping slide rod 237. The flow channel is T-shaped and is connected to the balance channel 2041 through the connecting hole 236.

[0044] Specifically, the damping slide rod 237 slides and seals against the inner wall of the damping hole 235. The sliding protrusion 2371 on its outer wall is an annular structure that abuts against one end of the guide rod 238 in the guide hole 234. The magnetic ring 239 at the other end of the guide rod 238 and the adsorption block 241 on the inner wall of the buffer cavity 204 are opposite magnetic poles facing each other, and always maintain a magnetic attraction. When the oil pressure in the damping hole 235 changes, the oil pushes the damping slide rod 237 to move along the channel. The sliding protrusion 2371 simultaneously pushes the guide rod 238, changing the distance between the magnetic ring 239 and the adsorption block 241. The magnetic attraction is adjusted accordingly, forming a flexible damping force to buffer the fluctuation of oil pressure. The damping spring 242 at the end of the damping hole 235 is sleeved on the outside of the damping slide bar 237, providing a reverse preload force for the damping slide bar 237 and further enhancing the buffering effect. The T-shaped flow channel on the damping slide bar 237 has a transverse section connected to the damping hole 235 and a longitudinal section aligned with the connecting hole 236. The flow cross section of the flow channel can be changed by moving the damping slide bar 237, thereby realizing the dynamic adjustment of the oil flow rate, ensuring the stability of the pressure in the buffer chamber 204, and avoiding sudden changes in the injection screw propulsion speed.

[0045] like Figure 13 As shown, the cam 302 has a multi-segment stepped profile, and its outer periphery includes three sets of circular arc segments connected in sequence along the circumference and a transition slope connecting adjacent circular arc segments.

[0046] Specifically, the cam 302 is a disc-shaped structure, sleeved on the shaft end of the injection screw and rotating synchronously with the screw. The radial height of its three sets of arc segments increases sequentially (e.g., the first arc segment has a radius of 10mm, the second 15mm, and the third 10mm), corresponding to the pressure requirements of the three stages of the injection molding process: "bottom filling," "body forming," and "mouth compaction." The transition slope between adjacent arc segments is a smooth arc with a slope controlled at 1:5 to avoid sudden force on the roller 305 when the cam 302 rotates, which could cause impact on the valve core 202. When the cam 302 rotates, the arc segments of different heights push the valve core 202 axially through the roller 305, changing the fit clearance between the valve core 202 and the throttle orifice 207, thereby switching the injection pressure level and achieving multi-stage pressure fit. The transition slope ensures that the valve core 202 moves smoothly, preventing sudden pressure rises and falls, adapting to the molding pressure requirements of different parts of the barrel, and improving the molding quality of the barrel.

[0047] like Figure 2 As shown, the injection screw includes a feeding section 1071, a compression section 1072 and a metering section 1073 connected in sequence. The feeding section 1071 is provided with a rocket head 1074, a guide sleeve 1075 and a check ring 1076; the feeding section 1071 is provided with a feeding hopper 112 and the compression section 1072 is provided with a heating ring 113.

[0048] Specifically, the injection screw's feeding section 1071, compression section 1072, and metering section 1073 are integrally molded structures. The pitch and groove depth of the three sections change sequentially: the feeding section 1071 has the largest pitch and the deepest groove, facilitating the receipt of plastic raw materials from the feed hopper 112 and their forward conveying; the compression section 1072 has a gradually decreasing pitch and shallower groove depth, which, in conjunction with the outer heating ring 113 (annular structure, fitted onto the outer wall of the compression section 1072, using electric heating, with a temperature adjustable to 180-220℃), achieves the melting, plasticizing, and compression of the raw materials, removing air bubbles; the metering section 1073 has the smallest pitch and the shallowest groove depth, used to meter the amount of molten material, ensuring consistent injection volume each time. The rocket head 1074 of the feeding section 1071 is a conical hollow structure with spiral guide ridges on its surface to guide the raw material smoothly into the compression section 1072; the guide sleeve 1075 is an annular structure, fitted at the junction of the rocket head 1074 and the compression section 1072, with a smooth inner wall and a gradually changing inner diameter to prevent raw material accumulation; the check ring 1076 is a one-way valve structure, fitted at the end of the feeding section 1071, allowing only the raw material to flow into the compression section 1072, preventing the molten material from flowing back, and ensuring the efficiency of raw material delivery and the accuracy of injection volume.

[0049] The above description is merely a preferred embodiment of the present invention and is not intended to limit the invention. Various modifications and variations can be made to the present invention by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the scope of protection of the present invention.

Claims

1. A multi-stage pressure-bonded plastic barrel injection molding device, comprising a base (101), wherein a molding module (102) and an injection module are provided on the base (101), characterized in that: The injection module includes a support base (103), an oil pump (104), and a barrel (105). A slide (106) is provided on the base (101). The support base (103) and the slide (106) are slidably connected. The oil pump (104) and the barrel (105) are installed on the support base (103). An injection screw is provided inside the barrel (105). One end of the barrel (105) is provided with an adjusting cylinder (108), and the injection screw is provided with an adjusting ring (109). The adjusting ring (109) divides the inner cavity of the adjusting cylinder (108) into a propulsion chamber (1081) and a retraction chamber (1082). Both the propulsion chamber (1081) and the retraction chamber (1082) are connected to the oil pump (104). The barrel (105) is provided with a control valve, a pressure regulating component and a solenoid valve (111) at one end. The control valve includes a valve body (201) and a valve core (202). The pressure regulating component includes a housing (301), a cam (302) and a gear set (303). The support base (103) is equipped with a drive motor (304), and the drive motor (304) is connected to the injection screw through the gear set (303); One end of the valve core (202) is located inside the valve body (201), and the other end of the valve core (202) is located inside the housing (301). The cam (302) is sleeved on the injection screw. A roller (305) is provided at one end of the valve core (202) located in the housing (301), and the roller (305) contacts the cam (302).

2. The multi-segment pressure bonding injection molding device for plastic barrels according to claim 1, characterized in that: The valve body (201) is provided with two sets of partitions (203). The two sets of partitions (203) divide the inner cavity of the valve body (201) into a buffer chamber (204), a control chamber (205), and a pressurizing chamber (206). The buffer chamber (204) is located at the outlet end of the control valve, the pressurizing chamber (206) is located at the inlet end of the control valve, and the control chamber (205) is located between the buffer chamber (204) and the pressurizing chamber (206).

3. The multi-segment pressure bonding injection molding device for plastic barrels according to claim 2, characterized in that: The control chamber (205) has three sets of throttling orifices (207) at one end near the pressurization chamber (206). One end of the valve core (202) is located inside the control chamber (205) and has two sets of through holes. The control chamber (205) is connected to the pressurization chamber (206) through the throttling orifices (207). The pressurizing chamber (206) is L-shaped, and a feedback hole (208) is provided inside the pressurizing chamber (206). An electric push rod (209) is installed on the valve body (201). The movable rod of the electric push rod (209) passes through the feedback hole (208). A pressure regulating spring (211) is provided on the movable rod of the electric push rod (209). A plug (212) is provided at the end of the pressure regulating spring (211) away from the movable rod of the electric push rod (209). A piston block (213) is slidably disposed in the buffer chamber (204), and a balance channel (2041) is provided in the buffer chamber (204). The buffer chamber (204) is connected to the opening end of the control valve through the balance channel (2041).

4. The multi-segment pressure bonding injection molding device for plastic barrels according to claim 3, characterized in that: The pressure regulating spring (211) is a variable diameter spiral structure, and the pressure regulating spring (211) decreases linearly along the axial direction from the end near the movable rod of the electric push rod (209) to the end near the plug (212); The feedback hole (208) is provided with a limiting ring (214) at one end near the pressurization chamber (206), the plug (212) is inserted into the limiting ring (214), and an integrally formed limiting platform (215) is provided at one end inside the feedback hole (208).

5. The multi-segment pressure bonding injection molding device for plastic barrels according to claim 4, characterized in that: The valve body (201) is provided with an adjustment hole (216) and a check hole. The adjustment hole (216) is located below the control cavity (205) and is connected to the control cavity (205). A return spring (217) is provided inside the adjustment hole (216). The check hole includes an execution channel (218), a drive channel (219), and an adjustment channel (221). A limit groove (222) is provided on the adjustment hole (216). The adjustment hole (216) is connected to the execution channel (218) through the limit groove (222). The execution channel (218) is connected to the drive channel (219) through the adjustment channel (221). The drive channel (219) is connected to the pressurization chamber (206). An execution piston (223) is slidably disposed in the execution channel (218), a drive piston (224) is disposed in the drive channel (219), a rotating shaft (225) is disposed in the adjustment channel (221), and a connecting rod (226) is rotatably disposed on the rotating shaft (225). The two ends of the connecting rod (226) are respectively connected to the execution piston (223) and the drive piston (224); A pawl (227) is rotatably provided in the limiting groove (222), the pawl (227) contacts the actuating piston (223), and multiple sets of retaining rings (228) are provided on the valve core (202), the pawl (227) contacts one of the retaining rings (228).

6. The multi-segment pressure bonding injection molding device for plastic barrels according to claim 5, characterized in that: The partition (203) has a rectifier channel (229). Multiple flow dividers (231) are evenly distributed on the inner wall of the rectifier channel (229). A flow guide channel (232) is formed between the flow dividers (231). The flow guide channel (232) is alternately provided with pits and protrusions. A grid (233) is provided at one end of the rectifier channel (229).

7. The multi-segment pressure bonding injection molding device for plastic barrels according to claim 6, characterized in that: The piston block (213) is provided with a guide hole (234), a damping hole (235), and a connecting hole (236). The guide hole (234) and the connecting hole (236) are perpendicularly connected to the damping hole (235). The damping hole (235) passes through the piston block (213), and the connecting hole (236) is connected to the balance channel (2041).

8. The multi-segment pressure bonding injection molding device for plastic barrels according to claim 7, characterized in that: The damping hole (235) is provided with a damping slide rod (237), the damping slide rod (237) is provided with a sliding protrusion (2371), the guide hole (234) is provided with a guide rod (238), one end of the guide rod (238) is in contact with the sliding protrusion (2371), and the other end is provided with a magnetic ring (239). The inner wall of the buffer cavity (204) is provided with an adsorption block (241), and the adsorption block (241) is magnetically connected to the magnetic ring (239). A damping spring (242) is provided at the end of the damping hole (235) away from the control cavity (205). The damping spring (242) is in contact with the damping slide rod (237). A flow channel is provided on the damping slide rod (237). The flow channel is T-shaped and is connected to the balance channel (2041) through the connecting hole (236).

9. The multi-segment pressure bonding injection molding device for plastic barrels according to claim 1, characterized in that: The cam (302) has a multi-segment stepped profile, and its outer periphery includes three sets of arc segments connected in sequence along the circumference and a transition slope connecting adjacent arc segments.

10. The multi-segment pressure bonding injection molding device for plastic barrels according to claim 1, characterized in that: The injection screw includes a feeding section (1071), a compression section (1072) and a metering section (1073) connected in sequence. The feeding section (1071) is provided with a rocket head (1074), a flow guide sleeve (1075) and a check ring (1076). The feeding section (1071) is provided with a feeding hopper (112), and the compression section (1072) is provided with a heating ring (113).

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