A method and system for starting control of injection molding machine components

Abstract

This invention relates to a method and system for starting injection molding machine components, relating to the field of injection molding machines. The method includes: Step 1: acquiring real-time pressure information of the moving component; Step 2: acquiring real-time position information of the moving component; Step 3: acquiring the type of hydraulic valve, including ordinary hydraulic valves and high-precision hydraulic valves; Step 40: determining different control methods based on the type of hydraulic valve, real-time pressure information, and real-time position information. The control methods include a pre-pressure method and a valve timing self-regulation method. If the type of hydraulic valve is the same as that of an ordinary hydraulic valve, the pre-pressure method is used for output; Step 41: If the type of hydraulic valve is the same as that of a high-precision hydraulic valve, the valve timing self-regulation method is used for output. This application has the effect of adaptively regulating hydraulic pressure output and valve timing.

Description

Technical Field

[0001] This invention relates to the field of injection molding machines, and in particular to a method and system for controlling the start-up of injection molding machine components. Background Technology

[0002] Hydraulic valves are the core control components of hydraulic systems. By changing the on / off state, flow direction, pressure, and flow rate of hydraulic oil, they can control the direction of movement, speed, output force, or torque of hydraulic actuators.

[0003] Hydraulic injection molding machines control the motor to output oil pressure through a controller, and at the same time control the opening and closing of hydraulic valves to control the oil circuit to establish pressure for different actions, driving the movement of various moving components. Currently, the existing industry technology control method is to set a fixed valve delay or valve output advance control.

[0004] Regarding the aforementioned technologies, when the response speed of the motor, the response time of the hydraulic valve, or the oil circuit structure are different, the time it takes for the hydraulic oil to reach the valve core and the controlled components will be different. Furthermore, when the oil temperature changes, the compression ratio of the hydraulic oil will also be different, and the system oil pressure build-up speed will also change, resulting in problems such as pressure build-up lag and unstable pressure output. Summary of the Invention

[0005] In order to achieve adaptive regulation of hydraulic pressure output and valve timing, and improve the control accuracy of injection molding machine actions, this invention provides a method and system for starting control of injection molding machine components.

[0006] The following technical solution is adopted: Firstly, a method for controlling the start-up of a component in an injection molding machine includes: Step 1: Obtain real-time pressure information on the moving components; Step 2: Obtain the real-time position information of the motion components; Step 3: Determine the types of hydraulic valves, including ordinary hydraulic valves and high-precision hydraulic valves; Step 40: Determine different control methods based on the type of hydraulic valve, real-time pressure information, and real-time position information. Control methods include pre-pressure method and valve timing self-regulation method. If the type of hydraulic valve is the same as that of ordinary hydraulic valve, the pre-pressure method is used for output. Step 41: If the type of hydraulic valve is the same as that of the high-precision hydraulic valve, output is performed using the valve timing self-regulation method.

[0007] By adopting the above technical solution, different products require different motion responses from various moving components. Adjusting the motor response can easily affect the overall performance of the machine. By directly inputting the required response time, and through intelligent adjustment of the pre-pressure and hydraulic valve timing, the motion response can be adaptive and self-adjusting. This reduces manual adjustment and increases the machine's versatility for multiple uses. Furthermore, it maximizes the high responsiveness and controllability of hydraulic valves to further improve the starting performance of each component.

[0008] Optional pre-stressing methods include: Step 10: When the type of hydraulic valve is the same as that of a regular hydraulic valve, output the preset output pressure to the moving component; Step 11: Obtain the position change of the moving component; Step 12: When the detected position change is not less than the preset reference position change, it is determined that the valve core of the hydraulic valve has been opened, and the output is performed according to the preset process parameters.

[0009] By adopting the above technical solution, the problem of valve core jamming or opening delay caused by insufficient pressure can be avoided by outputting the output pressure in advance. This ensures that the valve core is fully opened before switching to process parameters, thus improving the accuracy of injection molding.

[0010] Optionally, methods for obtaining the position change of the moving component include: Step 110: Obtain the position information of the motion component before and after the output pressure control; Step 111: Compare the position information before and after output pressure control to obtain the position change.

[0011] By adopting the above technical solution, the state of the valve core is determined by judging the motion state of the injection molding machine's moving components, ensuring that the moving components are micro-moved with small pressure, thus ensuring that the valve core is fully opened. This reduces the impact generated during startup and makes the operation smoother.

[0012] Optionally, valve timing self-regulation methods include: Step 20: When the type of hydraulic valve is consistent with that of the high-precision hydraulic valve, output the preset pre-pressure F1 to the motion component and output the preset initial valve timing delay time T1 to the hydraulic valve; Step 21: Obtain the screw speed; Step 22: Plot the injection curve based on the screw speed; Step 23: Determine the injection response P2 of the current mold based on the injection curve; Step 24: Determine the hydraulic valve delay time T2 according to the injection response P2 using a preset calculation method, and adjust the hydraulic valve before the next injection according to the hydraulic valve delay time T2.

[0013] By adopting the above technical solution, the uncertainty of hydraulic valve response and hydraulic oil pressure establishment speed is eliminated. By implementing a valve timing self-regulation method in advance, the start-up time of the hydraulic valve is delayed, which extends the high responsiveness and controllability of the high-precision hydraulic valve. By adjusting the hydraulic valve pre-pressure and hydraulic valve delay, the injection response time can be controlled, adaptively achieving the injection response time required by this machine, thus achieving precise control.

[0014] Optional, preset calculation methods include: Step 240: Determine the target range of the injection response based on the preset target value P1 and the deviation value a; Step 2410: When the injection response P2 < P1-a, increase the hydraulic valve delay time T2 before the next injection, T2 = T1 + α, obtain the new injection response P2 from the injection curve, and determine whether the new injection response P2 falls within the injection response target range until the new injection response P2 falls within the injection response target range. Step 2411: When the injection response P2 > P1 + a, reduce the hydraulic valve delay time T2 before the next injection, T2 = T1 - α, where α is a preset delay adjustment coefficient. Obtain the new injection response P2 from the injection curve and determine whether the new injection response P2 falls within the injection response target range until the new injection response P2 falls within the injection response target range.

[0015] By adopting the above technical solution and accurately calculating the new injection response P2 using a preset calculation method, the pre-pressure can be made more precise, the usage standard is standardized, and the injection molding is made more accurate.

[0016] Optionally, if the new injection response P2 obtained from the injection curve does not fall within the target range of the injection response, the following conditions may apply: Step 25: When the new injection response P2 does not fall within the target range of the injection response, determine the pre-adjustment pressure F2 based on the pre-pressure F1 and the preset pressure adjustment coefficient β, where F2 = F1 + β; Step 26: Determine the new injection response P2 based on the pre-adjustment pressure F2 until the new injection response P2 falls within the target range of the injection response.

[0017] By adopting the above technical solution, when adjusting the proportional valve delay cannot reach the injection response target value, the injection needs to reach its limit performance, which needs to be achieved by adjusting and increasing the value of the proportional valve pre-pressure. By increasing the pressure, ejection is formed, and the injection response is further improved.

[0018] Secondly, an injection molding machine component start-up control system includes: The pressure feedback module is used to detect the real-time pressure on the moving components and transmit it to the control module. The position feedback module is used to detect the position of the moving component and transmit it to the control module; The control module sends control signals to the output module based on the information fed back from the pressure feedback module and the position feedback module. The output module outputs control signals.

[0019] By adopting the above technical solution, the pressure feedback module, position feedback module, control module and output module only need to borrow the system pressure sensor and position ruler of each component of the injection molding machine itself, without additional cost or replacement of high-precision control modules or control valves.

[0020] In summary, this application includes at least one of the following beneficial technical effects: Different products require different motion responses from various moving components. Adjusting the motor response can easily affect the overall performance of the machine. By directly inputting the required response time, the machine can achieve adaptive and self-adjusting motion response through intelligent adjustment of the pre-pressure and hydraulic valve timing. The uncertainty in the response of hydraulic valves and the speed of hydraulic oil pressure build-up can be addressed by implementing a valve timing self-regulation method in advance. This delays the start-up time of the hydraulic valves, extending the high responsiveness and controllability of high-precision hydraulic valves. By adjusting the pre-pressure and delay of the hydraulic valves, the injection response time can be controlled, adaptively achieving the injection response time required by the machine, thus achieving precise control. Attached Figure Description

[0021] Figure 1 This is a schematic diagram of a component start-up control system for an injection molding machine; Figure 2 This is a schematic diagram of a component start-up control method for an injection molding machine; Figure 3 It is an injection curve. Detailed Implementation

[0022] The present invention will now be described in further detail with reference to the accompanying drawings and embodiments.

[0023] This application discloses a method and system for starting up injection molding machine components.

[0024] This application discloses a component start-up control system for an injection molding machine, referring to... Figure 1A component start-up control system for an injection molding machine includes a pressure feedback module, a position feedback module, a control module, and an output module. The pressure feedback module includes a pressure sensor installed within the injection molding machine, used to detect the real-time pressure on the moving component and transmit this information to the control module. The position feedback module includes an injection position gauge installed on the injection molding machine, used to detect the position of the moving component and transmit this information to the control module. The control module sends control signals to the output module based on the information fed back from the pressure and position feedback modules. The output module outputs the control signals.

[0025] Based on the same inventive concept, embodiments of the present invention provide a method for controlling the start-up of injection molding machine components, including: Step 1: Obtain real-time pressure information on the moving components.

[0026] Motion components refer to the parts in an injection molding machine that are hydraulically driven to perform preset actions.

[0027] Real-time pressure information refers to the pressure data of moving components that are detected and obtained in real time through the pressure feedback module.

[0028] The pressure feedback module detects the real-time pressure data of the moving components and feeds it back to the control module.

[0029] Step 2: Obtain the real-time position information of the motion components.

[0030] Real-time position information refers to the position coordinates of a moving component detected in real time under pressure.

[0031] The position feedback module acquires the coordinate position information of the moving components in real time and feeds it back to the control module.

[0032] Step 3: Determine the type of hydraulic valve, which includes ordinary hydraulic valves and high-precision hydraulic valves.

[0033] The type of hydraulic valve can be determined by scanning the barcode on the valve. Hydraulic valves include ordinary hydraulic valves and high-precision hydraulic valves, such as proportional valves.

[0034] Step 40: Determine different control methods based on the type of hydraulic valve, real-time pressure information, and real-time position information. Control methods include pre-pressure method and valve timing self-regulation method. If the type of hydraulic valve is the same as that of ordinary hydraulic valve, the pre-pressure method is used for output.

[0035] Different control methods are used for ordinary hydraulic valves and high-precision hydraulic valves, including a pre-pressure control method for ordinary hydraulic valves and a valve timing self-regulation method for high-precision hydraulic valves. When the detected hydraulic valve type is an ordinary hydraulic valve, the control module controls the output module to perform output control using the pre-pressure method.

[0036] Step 41: If the type of hydraulic valve is the same as that of the high-precision hydraulic valve, output is performed using the valve timing self-regulation method.

[0037] When the detected hydraulic valve type is a high-precision hydraulic valve, the control module controls the output module to perform output control using a valve timing self-regulation method.

[0038] Pre-stressing methods include: Step 10: When the type of hydraulic valve is the same as that of a normal hydraulic valve, output the preset output pressure to the moving component.

[0039] The preset output pressure refers to a small pressure that can drive the moving component without causing impact. In this embodiment, the pre-pressure is set to 10 bar, and the output pressure is a small pressure that can drive the screw without impacting the valve core. It can be adjusted up and down according to different models. The pressure sensor built into the injection molding machine is generally placed on the pressure valve plate, and the pressure difference with the injection valve port is small. Therefore, the system pressure here is directly fed back as the injection valve port pressure.

[0040] When the detected hydraulic valve type is a common hydraulic valve, the control module controls the pressure feedback module to output a small pressure to the moving component that can push the moving component without causing impact.

[0041] Step 11: Obtain the position change of the moving component.

[0042] The change in position refers to the difference in position of a moving component before and after being subjected to output pressure, that is, the distance it moves under the control of output pressure.

[0043] The position feedback module detects the position difference of the moving component before and after being subjected to output pressure.

[0044] Step 12: When the detected position change is not less than the preset reference position change, it is determined that the valve core of the hydraulic valve has been opened, and the output is performed according to the preset process parameters.

[0045] The preset reference position change refers to the critical position difference value for determining that the valve core is fully open. In this embodiment, the reference position change is 0.2mm. Due to its own error and interference, the injection position gauge connected to the injection molding machine generally runs by 0.1mm, that is, the error is 0.1mm. In this embodiment, it is set to 0.2mm to determine that the screw has actually moved forward. For some types of products, the position gauge error is larger and can be appropriately increased.

[0046] The preset process parameters refer to the parameters that are adjusted according to the different injection molding products.

[0047] The control module determines whether the change in valve core position is not less than the change in reference position. If the change in position is not less than the change in reference position, the control module determines that the valve core is open; if the change in position is greater than the change in reference position, the control module determines that the valve core is not open.

[0048] Methods for obtaining the position change of a moving component include: Step 110: Obtain the position information of the motion component before and after the output pressure control.

[0049] The position feedback module detects and obtains the position coordinates of the motion component before and after the output pressure.

[0050] Step 111: Compare the position information before and after output pressure control to obtain the position change.

[0051] The difference between the position coordinates of the moving component before and after the output pressure is applied is the change in position.

[0052] Valve timing self-regulation methods include: Step 20: When the type of hydraulic valve is consistent with that of the high-precision hydraulic valve, output the preset pre-pressure F1 to the motion component and output the preset initial valve timing delay time T1 to the hydraulic valve.

[0053] The pre-pressure F1 refers to the base pressure set for the high-precision hydraulic valve. Similar to the output pressure mentioned above, in this embodiment, the pre-pressure is set to 20 bar. The pre-pressure F1 is a small pressure that can push the screw without impacting the valve core. It can be adjusted up or down according to different models or different injection response requirements.

[0054] The preset initial valve timing delay time T1 is the time to delay the hydraulic valve start-up in order to adapt to the characteristics of high-precision hydraulic valves, ensure that the oil circuit has established pressure before the valve core opens, and avoid the action response delay caused by the lack of pressure establishment. It is used to delay the hydraulic valve output so that the basic pressure can be established before the hydraulic valve port is opened. In this embodiment, the valve timing delay initialization is set to 50ms.

[0055] When the detected hydraulic valve type is a high-precision hydraulic valve, the control module controls the pressure feedback module to output the pre-pressure to the moving component, and controls the hydraulic valve to start after a delay of the initial valve timing delay time T1.

[0056] Step 21: Obtain the screw speed.

[0057] Screw speed refers to the instantaneous axial movement speed of the injection screw in an injection molding machine.

[0058] The position of the screw is detected in real time by the position feedback module, and the screw speed is calculated by the ratio of the change in position to time.

[0059] Step 22: Draw the injection curve based on the screw speed.

[0060] An injection curve is a graph that uses time as the horizontal axis and screw speed as the vertical axis to show the dynamic changes in screw speed.

[0061] Plot the injection curve based on the screw speed and time.

[0062] Step 23: Determine the injection response P2 of the current mold based on the injection curve.

[0063] Injection response P2 refers to the initiation response time of the injection action.

[0064] The injection response time P2 of the current mold can be determined based on the injection curve.

[0065] Step 24: Determine the hydraulic valve delay time T2 according to the injection response P2 using a preset calculation method, and adjust the hydraulic valve before the next injection according to the hydraulic valve delay time T2.

[0066] The hydraulic valve delay time T2 refers to the hydraulic valve output delay time after adjustment to adapt to the screw movement speed.

[0067] The control module determines the hydraulic valve delay time T2 based on the injection response P2 and through a preset calculation method. Before the next injection, the control module controls the output module to adjust the hydraulic valve to extend the hydraulic valve delay time by T2.

[0068] The preset calculation methods include: Step 240: Determine the target range of the injection response based on the preset target value P1 and deviation value a.

[0069] The preset injection response target value P1 refers to the injection response time set according to the product.

[0070] The deviation value 'a' refers to the allowable error range of the injection response.

[0071] The target range for injection response refers to the time interval within which an injection response is met.

[0072] The time interval that meets the injection response is determined based on the target value P1 of the injection response and the error range value of the injection response.

[0073] Step 2410: When the injection response P2 exceeds the injection response target range and P2 < P1-a, increase the hydraulic valve delay time T2 before the next injection, T2 = T1 + α, where α is a preset delay adjustment coefficient. Obtain the new injection response P2 from the injection curve and determine whether the new injection response P2 falls within the injection response target range until the new injection response P2 falls within the injection response target range.

[0074] When the injection response P2 exceeds the target range of the injection response and the injection response P2 < P1 - a, the control module controls the hydraulic valve to increase the hydraulic valve delay time T2 before the next injection. At this time, T2 = T1 + α, where α is a preset delay adjustment coefficient. The new injection response P2 is obtained in the new injection curve, and it is determined whether the new injection response P2 falls within the target range of the injection response, until the new injection response P2 falls within the target range of the injection response.

[0075] Step 2411: When the injection response P2 exceeds the injection response target range and P2 > P1 + a, reduce the hydraulic valve delay time T2 before the next injection, T2 = T1 - α, obtain the new injection response P2 from the injection curve, and determine whether the new injection response P2 falls within the injection response target range until the new injection response P2 falls within the injection response target range.

[0076] When the injection response P2 exceeds the target range of the injection response and the injection response P2 > P1 + a, the control module controls the hydraulic valve to reduce the hydraulic valve delay time T2 before the next injection. At this time, T2 = T1 + α, where α is a preset delay adjustment coefficient. The new injection response P2 is obtained in the new injection curve. The control module determines whether the new injection response P2 falls within the target range of the injection response until the new injection response P2 falls within the target range of the injection response.

[0077] When the new injection response P2 obtained from the injection curve does not fall within the target range of the injection response, the control methods include: Step 25: When the new injection response P2 does not fall within the target range of the injection response, determine the pre-adjustment pressure F2 based on the pre-pressure F1 and the preset pressure adjustment coefficient β, where F2 = F1 + β.

[0078] The pre-adjustment pressure F2 refers to the pre-adjustment pressure after re-optimization following the failure of the delay adjustment.

[0079] When the new injection response P2 does not fall within the target range of the injection response, the new pre-pressure is re-optimized and determined based on the pre-pressure F1 and the pressure adjustment coefficient β, which is the pre-adjustment pressure F2, F2=F1+β.

[0080] Step 26: Determine the new injection response P2 based on the pre-adjustment pressure F2 until the new injection response P2 falls within the target range of the injection response.

[0081] The position feedback module records the pre-adjustment pressure F2 to control the new screw movement speed and plots a new injection curve. The control module pre-calculates and determines the new injection response P2 in the new injection curve. The control output module outputs the response when the new injection response P2 falls within the target range of the injection response.

[0082] The above description is merely a preferred embodiment of the present invention. The scope of protection of the present invention is not limited to the above embodiments. All technical solutions falling within the scope of the present invention's concept are within the scope of protection of the present invention. It should be noted that for those skilled in the art, any improvements and modifications made without departing from the principles of the present invention should also be considered within the scope of protection of the present invention.

Claims

1. A method for controlling the start-up of a component in an injection molding machine, characterized in that, include: Step 1: Obtain real-time pressure information on the moving components; Step 2: Obtain the real-time position information of the motion components; Step 3: Determine the types of hydraulic valves, including ordinary hydraulic valves and high-precision hydraulic valves; Step 40: Determine different control methods based on the type of hydraulic valve, real-time pressure information, and real-time position information. Control methods include pre-pressure method and valve timing self-regulation method. If the type of hydraulic valve is the same as that of ordinary hydraulic valve, the pre-pressure method is used for output. Step 41: If the type of hydraulic valve is the same as that of the high-precision hydraulic valve, output is performed using the valve timing self-regulation method.

2. The injection molding machine component start-up control method according to claim 1, characterized in that, Pre-stressing methods include: Step 10: When the type of hydraulic valve is the same as that of a normal hydraulic valve, output the preset output pressure to the moving component; Step 11: Obtain the position change of the moving component; Step 12: When the detected position change is not less than the preset reference position change, it is determined that the valve core of the hydraulic valve has been opened, and the output is performed according to the preset process parameters.

3. The injection molding machine component start-up control method according to claim 2, characterized in that, Methods for obtaining the position change of a moving component include: Step 110: Obtain the position information of the motion component before and after the output pressure control; Step 111: Compare the position information before and after output pressure control to obtain the position change.

4. The injection molding machine component start-up control method according to claim 1, characterized in that, Valve timing self-regulation methods include: Step 20: When the type of hydraulic valve is consistent with that of the high-precision hydraulic valve, output the preset pre-pressure F1 to the motion component and output the preset initial valve timing delay time T1 to the hydraulic valve; Step 21: Obtain the screw speed; Step 22: Plot the injection curve based on the screw speed; Step 23: Determine the injection response P2 of the current mold based on the injection curve; Step 24: Determine the hydraulic valve delay time T2 according to the injection response P2 using a preset calculation method, and adjust the hydraulic valve before the next injection according to the hydraulic valve delay time T2.

5. The injection molding machine component start-up control method according to claim 4, characterized in that, The preset calculation methods include: Step 240: Determine the target range of the injection response based on the preset target value P1 and the deviation value a; Step 2410: When the injection response P2 exceeds the injection response target range and P2 < P1-a, increase the hydraulic valve delay time T2 before the next injection, T2 = T1 + α, where α is a preset delay adjustment coefficient. Obtain the new injection response P2 from the injection curve and determine whether the new injection response P2 falls within the injection response target range until the new injection response P2 falls within the injection response target range. Step 2411: When the injection response P2 exceeds the injection response target range and P2 > P1 + a, reduce the hydraulic valve delay time T2 before the next injection, T2 = T1 - α, obtain the new injection response P2 from the injection curve, and determine whether the new injection response P2 falls within the injection response target range until the new injection response P2 falls within the injection response target range.

6. The injection molding machine component start-up control method according to claim 5, characterized in that, When the new injection response P2 obtained from the injection curve does not fall within the target range of the injection response, the control methods include: Step 25: When the new injection response P2 does not fall within the target range of the injection response, determine the pre-adjustment pressure F2 based on the pre-pressure F1 and the preset pressure adjustment coefficient β, where F2 = F1 + β; Step 26: Determine the new injection response P2 based on the pre-adjustment pressure F2 until the new injection response P2 falls within the target range of the injection response.

7. A component start-up control system for an injection molding machine, wherein the start-up control method for an injection molding machine component as described in any one of claims 1 to 6 is used for control, characterized in that, include: The pressure feedback module is used to detect the real-time pressure on the moving components and transmit it to the control module. The position feedback module is used to detect the position of the moving component and transmit it to the control module; The control module sends control signals to the output module based on the information fed back from the pressure feedback module and the position feedback module. The output module outputs control signals.

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