Design method of injection molding machine injection transmission mechanism

Abstract

The present invention provides a design method for an injection molding machine injection transmission mechanism, comprising: calculating the motor speed n1, the motor stall torque T1 and the motor instantaneous power P required during the injection process of the injection molding machine according to the structural parameters of the screw, the process parameters of the injection molding machine, the structural parameters of the transmission component and the transmission efficiency. 瞬 ; According to the instantaneous power P of the motor 瞬 And the motor overload factor λ3 calculate the motor recommended power P 建议 ; Based on the motor speed n1, motor stall torque T1 and motor recommended power P 建议 Select the servo motor so that the speed of the selected servo motor is greater than or equal to the motor speed n1, the stall torque of the selected servo motor is greater than or equal to the motor stall torque T1, and the rated power of the selected servo motor is greater than or equal to the motor recommended power P 建议 The injection molding machine injection transmission mechanism of the present invention solves the problem that the servo motor of the injection molding machine injection transmission mechanism in the prior art has too much surplus when selecting the type, resulting in cost waste.

Description

Technical Field

[0001] The invention relates to the field of injection molding machines, and in particular to a design method for a glue injection transmission mechanism of an injection molding machine. Background Art

[0002] The injection transmission mechanism of the fully electric injection molding machine is the core structure of the injection molding machine. The performance of its design directly determines the working efficiency and molding quality of the injection molding machine. The fully electric injection molding machine involves many core components. Accurate design calculation plays a vital role in ensuring the reliability of the machine and reducing the cost of the machine.

[0003] In the prior art, the injection drive mechanism of the injection molding machine determines the rated power required by the servo motor during the injection process based on the axial force of the screw, and selects the model of the servo motor based on the rated power so that the rated power of the selected servo motor is much larger than the power required for the injection process of the injection molding machine; and further selects the model of the driver based on the selected servo motor.

[0004] However, the above-mentioned design method of the injection molding machine injection transmission mechanism will cause too much margin when selecting the servo motor, which will further cause too much margin when selecting the driver, resulting in cost waste. Summary of the invention

[0005] The main purpose of the present invention is to provide a design method for an injection molding machine injection transmission mechanism to solve the problem of excessive surplus when selecting a servo motor for the injection molding machine injection transmission mechanism in the prior art, resulting in cost waste.

[0006] In order to achieve the above-mentioned object, the present invention provides a design method for an injection molding machine injection transmission mechanism, the injection molding machine includes a screw and at least one injection transmission mechanism, the injection transmission mechanism includes a servo motor and a transmission assembly, the servo motor drives the screw to move through the transmission assembly, and the design method for the injection molding machine injection transmission mechanism includes: according to the structural parameters of the screw, the process parameters of the injection molding machine, the structural parameters of the transmission assembly and the transmission efficiency, the motor speed n1, the motor stall torque T1 and the motor instantaneous power P required during the injection process of the injection molding machine are calculated 瞬 ; According to the instantaneous power P of the motor 瞬 And the motor overload factor λ3 calculate the motor recommended power P 建议 ; Based on the motor speed n1, motor stall torque T1 and motor recommended power P 建议 Select the servo motor so that the speed of the selected servo motor is greater than or equal to the motor speed n1, the stall torque of the selected servo motor is greater than or equal to the motor stall torque T1, and the rated power of the selected servo motor is greater than or equal to the motor recommended power P 建议 .

[0007] Further, the transmission assembly includes a synchronous pulley assembly and a ball screw, the synchronous pulley assembly includes a first pulley, a second pulley and a synchronous belt, the synchronous belt is sleeved on the first pulley and the second pulley, the motor is connected to the first pulley, the second pulley is connected to the screw of the ball screw, and the screw nut of the ball screw is connected to the screw; the method for calculating the motor speed n1 required during the injection process of the injection molding machine according to the structural parameters of the screw, the process parameters of the injection molding machine, the structural parameters of the transmission assembly and the transmission efficiency includes: calculating the motor speed n1 according to the maximum injection speed v, the lead S of the screw and the pulley transmission ratio i; wherein, Calculate the pulley transmission ratio i according to the first pulley tooth number Z1 and the second pulley tooth number Z2;

[0008] Furthermore, the transmission assembly includes a synchronous pulley assembly and a ball screw, the synchronous pulley assembly includes a first pulley, a second pulley and a synchronous belt, the synchronous belt is sleeved on the first pulley and the second pulley, the motor is connected to the first pulley, the second pulley is connected to the screw of the ball screw, and the screw nut of the ball screw is connected to the screw; the injection molding machine also includes a support seat, the screw is passed through the support seat, a bearing assembly is arranged between the screw and the support seat, and the bearing assembly is sleeved on the screw; the method for calculating the motor stall torque T1 required during the injection process of the injection molding machine according to the structural parameters of the screw, the process parameters of the injection molding machine, the structural parameters of the transmission assembly and the transmission efficiency includes: according to the calculation formula Calculate the motor stall torque T1; where d is the diameter of the screw, S is the lead of the screw, P1 is the maximum holding pressure, i is the pulley transmission ratio; η1 is the belt transmission efficiency, η2 is the screw transmission efficiency, and η3 is the bearing transmission efficiency; calculate the pulley transmission ratio i based on the number of teeth Z1 of the first pulley and the number of teeth Z2 of the second pulley;

[0009] Furthermore, the transmission assembly includes a synchronous pulley assembly and a ball screw, the synchronous pulley assembly includes a first pulley, a second pulley and a synchronous belt, the synchronous belt is sleeved on the first pulley and the second pulley, the motor is connected to the first pulley, the second pulley is connected to the screw of the ball screw, and the screw nut of the ball screw is connected to the screw; the injection molding machine also includes a support seat, the screw is passed through the support seat, a bearing assembly is arranged between the screw and the support seat, and the bearing assembly is sleeved on the screw; according to the structural parameters of the screw, the process parameters of the injection molding machine, the structural parameters of the transmission assembly and the transmission efficiency, the instantaneous power P of the motor required during the injection process of the injection molding machine is calculated 瞬 The method includes: according to the calculation formula Calculate the instantaneous power P of the motor 瞬; Wherein, d is the diameter of the screw, η1 is the belt transmission efficiency, η2 is the screw transmission efficiency, η3 is the bearing transmission efficiency, n is the number of screws, P is the maximum injection pressure, v is the maximum injection speed, and λ2 is the coordination coefficient between injection speed and pressure.

[0010] Furthermore, according to the instantaneous power P of the motor 瞬 And the motor overload factor λ3 calculate the motor recommended power P 建议 The method includes: according to the calculation formula Calculate the recommended motor power P 建议 .

[0011] Furthermore, the injection transmission mechanism also includes a driver, which is connected to the servo motor in communication; the design method of the injection transmission mechanism of the injection molding machine includes: obtaining the torque constant k and the rated torque T of the selected servo motor when the temperature rise is 100°C N , Maximum torque T max , Rated current I 额 , Maximum current I max And the servo motor rated speed n 额 ; According to the maximum torque T2 of the servo motor during the injection process, as well as the torque constant k and the rated torque T N , Maximum torque T max , Rated current I 额 , Maximum current I max Calculate the maximum current I that the driver will reach during the operation of the servo motor 驱动器max ; According to the maximum current I of the driver 驱动器max Select the driver so that the maximum current of the selected driver is greater than or equal to the maximum current I 驱动器max .

[0012] Furthermore, according to the maximum torque T2 of the servo motor during the injection process, the torque constant k, the rated torque T N , Maximum torque T max , Rated current I 额 , Maximum current I max Calculate the maximum current I that the driver will reach during the operation of the servo motor 驱动器max The method includes: according to the calculation formula Calculate the maximum driver current I 驱动器max ;in, P is the maximum injection pressure, P1 is the maximum holding pressure; η 额 is the rated torque efficiency, η max is the maximum torque efficiency,

[0013] Furthermore, the design method of the injection molding machine injection transmission mechanism includes: obtaining the voltage constant K of the selected driver e , torque constant K t , line resistance R w , pole number PN and line inductance Lw; check the selected driver, the check conditions are: Among them, Vmax is the maximum voltage of the servo motor during operation, E min is the minimum main voltage of the driver; pk is the maximum angular velocity of the servo motor, C max is the maximum torque of the servo motor, Cw max =T2; If the above verification conditions are met, it means that the selected driver meets the working conditions. If not, a higher-speed servo motor needs to be selected to match a larger driver drive current.

[0014] Furthermore, the transmission assembly includes a ball screw, the servo motor is connected to the screw of the ball screw, and the screw nut of the ball screw is connected to the screw; the design method of the injection molding machine injection transmission mechanism also includes: calculating the maximum axial force F of the screw based on the diameter d of the screw, the number n of the screws and the maximum injection pressure P; selecting the ball screw based on the maximum axial force F of the screw, so that the maximum axial force of the selected ball screw is greater than or equal to the maximum axial force F of the screw.

[0015] Further, the method for calculating the maximum axial force F of the screw according to the diameter d of the screw, the number n of the screws and the maximum injection pressure P includes: according to the calculation formula Calculate the maximum axial force F of the screw.

[0016] The design method of the injection molding machine injection transmission mechanism of the present invention calculates the motor speed n1, motor stall torque T1 and motor instantaneous power P required during the injection process of the injection molding machine according to the structural parameters of the screw, the process parameters of the injection molding machine, the structural parameters of the transmission component and the transmission efficiency. 瞬 ; and according to the instantaneous power P of the motor 瞬 And the motor overload factor λ3 calculate the motor recommended power P 建议 When selecting a servo motor, the speed of the selected servo motor is greater than or equal to the motor speed n1, and the stall torque of the servo motor is greater than or equal to the motor stall torque T1, and the rated power of the servo motor is greater than or equal to the motor recommended power P 建议 Since the design method of the injection molding machine injection transmission mechanism is based on the motor speed n1, motor stall torque T1 and motor recommended power P 建议The three calculation results are matched with the servo motor models in the servo motor sample, and the servo motor that meets the conditions is selected. The design process is more accurate and will not cause cost waste due to excessive surplus. It can also avoid the situation where the selected model is too small to meet the equipment requirements, thereby ensuring the reliability of the servo motor during use. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] The drawings constituting a part of the present application are used to provide a further understanding of the present invention. The exemplary embodiments of the present invention and their descriptions are used to explain the present invention and do not constitute an improper limitation of the present invention. In the drawings:

[0018] Figure 1 A flow chart showing an embodiment of a method for designing a plastic injection transmission mechanism for an injection molding machine according to the present invention;

[0019] Figure 2 A schematic structural diagram of an embodiment of an injection molding machine according to the present invention is shown;

[0020] Figure 3 A cross-sectional view of an embodiment of an injection molding machine according to the invention is shown.

[0021] The above drawings include the following reference numerals:

[0022] 10. Screw; 20. Servo motor; 30. First pulley; 40. Second pulley; 50. Synchronous belt; 60. Lead screw; 70. Lead screw nut; 80. Bearing assembly. DETAILED DESCRIPTION

[0023] It should be noted that, in the absence of conflict, the embodiments and features in the embodiments of the present application can be combined with each other. The present invention will be described in detail below with reference to the accompanying drawings and in combination with the embodiments.

[0024] It should be noted that the following detailed descriptions are illustrative and are intended to provide further explanation of the present application. Unless otherwise specified, all technical and scientific terms used herein have the same meanings as those commonly understood by those skilled in the art to which the present application belongs.

[0025] It should be noted that the terms used herein are only for describing specific embodiments and are not intended to limit the exemplary embodiments according to the present application. As used herein, unless the context clearly indicates otherwise, the singular form is also intended to include the plural form. In addition, it should be understood that when the terms "comprise" and / or "include" are used in this specification, it indicates the presence of features, steps, operations, devices, components and / or combinations thereof.

[0026] The present invention provides a design method for the injection molding machine injection transmission mechanism, please refer to Figures 1 to 3The injection molding machine includes a screw 10 and at least one injection transmission mechanism, the injection transmission mechanism includes a servo motor 20 and a transmission assembly, and the servo motor 20 drives the screw 10 to move through the transmission assembly; the design method of the injection transmission mechanism of the injection molding machine includes:

[0027] Step S100, the motor speed n1, motor stall torque T1 and motor instantaneous power P required during the injection process of the injection molding machine are calculated according to the structural parameters of the screw, the process parameters of the injection molding machine, the structural parameters of the transmission component and the transmission efficiency. 瞬 ;

[0028] Step S200: according to the instantaneous power P of the motor 瞬 And the motor overload factor λ3 calculate the motor recommended power P 建议 ;

[0029] Step S300: according to the motor speed n1, the motor stall torque T1 and the motor recommended power P 建议 Select the servo motor so that the speed of the selected servo motor is greater than or equal to the motor speed n1, the stall torque of the selected servo motor is greater than or equal to the motor stall torque T1, and the rated power of the selected servo motor is greater than or equal to the motor recommended power P 建议 .

[0030] The design method of the injection molding machine injection transmission mechanism of the present invention calculates the motor speed n1, motor stall torque T1 and motor instantaneous power P required during the injection process of the injection molding machine according to the structural parameters of the screw, the process parameters of the injection molding machine, the structural parameters of the transmission component and the transmission efficiency. 瞬 ; and according to the instantaneous power P of the motor 瞬 And the motor overload factor λ3 calculate the motor recommended power P 建议 When selecting a servo motor, the speed of the selected servo motor is greater than or equal to the motor speed n1, and the stall torque of the servo motor is greater than or equal to the motor stall torque T1, and the rated power of the servo motor is greater than or equal to the motor recommended power P 建议 Since the design method of the injection molding machine injection transmission mechanism is based on the motor speed n1, motor stall torque T1 and motor recommended power P 建议 The three calculation results are matched with the servo motor models in the servo motor sample, and the servo motor that meets the conditions is selected. The design process is more accurate and will not cause cost waste due to excessive surplus. It can also avoid the situation where the selected model is too small to meet the equipment requirements, thereby ensuring the reliability of the servo motor during use.

[0031] Specifically, the unit of the motor speed n1 is rpm.

[0032] Specifically, the motor stall torque is also referred to as the motor stall torque, and the unit of the motor stall torque T1 is N·m.

[0033] Specifically, the motor overload factor λ3 is a multiple of the allowable servo motor overload.

[0034] Specifically, the instantaneous power of the motor P 瞬 The unit is KW, the recommended motor power P 建议 The unit is KW.

[0035] In this embodiment, the transmission assembly includes a synchronous pulley assembly and a ball screw, the synchronous pulley assembly includes a first pulley 30, a second pulley 40 and a synchronous belt 50, the synchronous belt 50 is sleeved on the first pulley 30 and the second pulley 40, the servo motor 20 is connected to the first pulley 30, the second pulley 40 is connected to the screw 60 of the ball screw, and the screw nut 70 of the ball screw is connected to the screw 10.

[0036] Specifically, the lead screw nut 70 is connected to the pressure sensor, the pressure sensor is connected to the melt glue seat, and the screw rod 10 is connected to the melt glue seat. Such an arrangement realizes the connection between the lead screw nut 70 and the screw rod 10.

[0037] In this embodiment, the method for calculating the motor speed n1 required during the injection process of the injection molding machine according to the structural parameters of the screw, the process parameters of the injection molding machine, the structural parameters of the transmission assembly and the transmission efficiency includes: calculating the motor speed n1 according to the maximum injection speed v, the lead S of the screw and the pulley transmission ratio i; wherein, Calculate the pulley transmission ratio i according to the first pulley tooth number Z1 and the second pulley tooth number Z2; This setting can accurately calculate the motor speed n1 and ensure the reasonable selection of the servo motor.

[0038] In this embodiment, the injection molding machine further comprises a support seat, a lead screw is passed through the support seat, a bearing assembly 80 is arranged between the lead screw and the support seat, and the bearing assembly 80 is sleeved on the lead screw. Specifically, a bearing seat is arranged on the support seat, and the bearing assembly 80 is arranged between the lead screw and the bearing seat.

[0039] In this embodiment, the method for calculating the motor stall torque T1 required during the injection process of the injection molding machine according to the structural parameters of the screw, the process parameters of the injection molding machine, the structural parameters of the transmission component and the transmission efficiency includes: according to the calculation formula Calculate the motor stall torque T1; where d is the diameter of the screw, S is the lead of the screw, P1 is the maximum holding pressure, i is the pulley transmission ratio; η1 is the belt transmission efficiency, η2 is the screw transmission efficiency, and η3 is the bearing transmission efficiency; calculate the pulley transmission ratio i based on the number of teeth Z1 of the first pulley and the number of teeth Z2 of the second pulley; This setting can accurately calculate the motor stall torque T1 and ensure the selection of the servo motor is reasonable.

[0040] Specifically, the belt transmission efficiency ranges from 0.93 to 0.98, the bearing transmission efficiency ranges from 0.92 to 0.99, and the screw transmission efficiency ranges from 0.9 to 0.98.

[0041] In this embodiment, the instantaneous power P of the motor required during the injection process of the injection molding machine is calculated based on the structural parameters of the screw, the process parameters of the injection molding machine, the structural parameters of the transmission component, and the transmission efficiency. 瞬 The method includes: according to the calculation formula Calculate the instantaneous power P of the motor 瞬 ; Where d is the diameter of the screw, η1 is the belt transmission efficiency, η2 is the screw transmission efficiency, η3 is the bearing transmission efficiency, n is the number of screws, P is the maximum injection pressure, v is the maximum injection speed, and λ2 is the coordination coefficient between injection speed and pressure. This setting can accurately calculate the instantaneous power P of the motor. 瞬 , ensure the selection of servo motor is reasonable.

[0042] In this embodiment, according to the instantaneous power P of the motor 瞬 And the motor overload factor λ3 calculate the motor recommended power P 建议 The method includes: according to the calculation formula Calculate the recommended motor power P 建议 By selecting a servo motor with a rated power greater than or equal to the motor's recommended power P 建议 Instead of calculating the motor rated power required under the working condition based on the axial force of the screw, select a servo motor with a rated power greater than or equal to the motor rated power to avoid over-selecting a servo motor and causing cost waste.

[0043] In this embodiment, the injection transmission mechanism also includes a driver, which is communicatively connected to the servo motor; the design method of the injection transmission mechanism of the injection molding machine includes: obtaining the torque constant k and the rated torque T of the selected servo motor when the temperature rise is 100°C N , Maximum torque T max , Rated current I 额 , Maximum current I max And the servo motor rated speed n 额 ; According to the maximum torque T2 of the servo motor during the injection process, as well as the torque constant k and the rated torque T N , Maximum torque T max , Rated current I 额 , Maximum current I max Calculate the maximum current I that the driver will reach during the operation of the servo motor 驱动器max; According to the maximum current I of the driver 驱动器max Select the driver so that the maximum current of the selected driver is greater than or equal to the maximum current I 驱动器max This setting ensures that the driver selection is reasonable. Accurate calculation can ensure that the driver margin is not too large when selecting the driver, resulting in cost waste, and can also avoid the situation where the driver selection is too small to meet the equipment requirements.

[0044] Specifically, the design method of the injection molding machine injection transmission mechanism further includes: obtaining the stall torque T'1 of the selected servo motor when the temperature rise is 100°C.

[0045] In this embodiment, according to the maximum torque T2 of the servo motor during the injection process, the torque constant k, the rated torque T N , Maximum torque T max , Rated current I 额 , Maximum current I max Calculate the maximum current I that the driver will reach during the operation of the servo motor 驱动器max The method includes: according to the calculation formula Calculate the maximum driver current I 驱动器max ;in, P is the maximum injection pressure, P1 is the maximum holding pressure; η 额 is the rated torque efficiency, η max is the maximum torque efficiency, Specifically, according to the above, the peak current that the driver will reach during the operation of the servo motor can be calculated. Based on this result, the driver can be selected from the driver sample. The maximum current of the selected driver should be greater than the calculated current peak. This setting can accurately calculate the maximum current I of the driver. 驱动器max , to ensure the reasonable selection of the drive.

[0046] Specifically, the torque constant k is the ratio of the torque to the difference between the rated current and the no-load current.

[0047] In this embodiment, the design method of the injection molding machine injection transmission mechanism includes: obtaining the voltage constant K of the selected driver e , torque constant K t , line resistance R w , pole number PN and line inductance Lw; check the selected driver, the check conditions are: Among them, Vmax is the maximum voltage of the servo motor during operation, E min is the minimum main voltage of the driver; pk is the maximum angular velocity of the servo motor, C max is the maximum torque of the servo motor, Cwmax =T2; If the above verification conditions are met, it means that the selected driver meets the working conditions. If not, a higher-speed servo motor needs to be selected to match a larger driver drive current.

[0048] It should be noted that choosing a higher-speed servo motor means choosing a servo motor with a higher motor speed n1, and matching a larger driver current means matching a servo motor with a higher maximum driver current I 驱动器max Driver; Among them, when the servo motor specifications are larger, the corresponding matching driver maximum current will also increase accordingly.

[0049] In specific implementation, after the driver selection is completed, the selected driver needs to be reverse checked to ensure whether it meets the actual requirements. That is, it needs to be tested for power size calculation. The voltage required by the servo motor when outputting maximum torque must be less than the voltage that the driver can provide; among them, the minimum main voltage of the driver is usually 90% of the rated voltage. Since the driver model has been determined and the rated voltage is known, the minimum main voltage E of the driver can be calculated. min .

[0050] Specifically, the voltage constant is the proportional constant of the linear response relationship between the mechanical and electrical quantities of the piezoelectric body, the torque constant is the ratio of the torque to the difference between the rated current and the no-load current, the line resistance is the resistance of a single coil, the number of poles is the number of magnetic poles hidden in the motor stator, and the line inductance is the inductance of a single coil.

[0051] In this embodiment, the transmission assembly includes a ball screw, the servo motor is connected to the screw of the ball screw, and the screw nut of the ball screw is connected to the screw rod; the design method of the injection molding machine injection transmission mechanism also includes: calculating the maximum axial force F of the screw according to the diameter d of the screw rod, the number n of the screw rods and the maximum injection pressure P; selecting the ball screw according to the maximum axial force F of the screw, so that the maximum axial force of the selected ball screw is greater than or equal to the maximum axial force F of the screw. Specifically, according to the calculated maximum axial force F of the screw, a ball screw model whose maximum axial force of the ball screw is greater than the calculated value is selected from the ball screw sample, and such a design method can select a suitable ball screw.

[0052] In this embodiment, the method for calculating the maximum axial force F of the screw according to the diameter d of the screw, the number n of the screws and the maximum injection pressure P includes: according to the calculation formula Calculate the maximum axial force F of the screw. The unit of the maximum axial force F of the screw is N. The maximum axial force F of the screw can be accurately calculated through this calculation formula, ensuring that the selection can meet the equipment requirements without incurring cost waste.

[0053] In the specific implementation, the known quantities determined according to the design requirements of the injection molding machine are: screw diameter d, in mm; maximum injection pressure P, in MPa; number of screws n; maximum holding pressure P1, in MPa; screw lead S, in mm; maximum injection speed v, in mm / s; number of teeth on the first pulley Z1; number of teeth on the second pulley Z2; belt transmission efficiency η1; screw transmission efficiency η2; bearing transmission efficiency η3; injection stroke L, in mm; stroke utilization λ1; injection speed and pressure coordination coefficient λ2; motor overload coefficient λ3; injection molding cycle T, in s. Among them, motor speed n1, motor stall torque T1 and motor instantaneous power P 瞬 All are calculated under this working condition.

[0054] Specifically, injection pressure refers to the maximum pressure applied by the screw to the molten material per unit area during injection, the maximum holding pressure is the maximum pressure applied after the material fills the mold, the maximum injection speed is the maximum axial speed of the screw, the injection stroke is the maximum axial movement distance of the screw nut, the stroke utilization rate is the ratio of the maximum axial movement distance of the screw nut to the injection stroke standard during design, the coordination coefficient of injection speed and pressure is a constant for coordinating the balance between injection speed and injection pressure, and the injection molding cycle is the time required to complete one injection molding.

[0055] In specific implementation, after the model of the servo motor is determined, the torque constant k and rated torque T of the servo motor when the temperature rises by 100°C are N , Maximum torque T max , Rated current I 额 And the maximum current I max , servo motor rated speed n 额 , the stall torque T'1 is a known quantity.

[0056] In specific implementation, after the driver model is determined, the driver voltage constant K e , torque constant K t , line resistance R w , pole number PN and line inductance Lw are known quantities.

[0057] It should be noted that, when the injection molding machine includes two or more injection transmission mechanisms, the values ​​of the motor and the driver calculated above are the values ​​of a single motor and a single driver, and the two or more motors are of the same type, and the two or more drivers are of the same type; for example, when the injection molding machine includes two injection transmission mechanisms, the values ​​of the motor calculated above are the values ​​of a single motor, and the two motors are of the same type.

[0058] This application is used for the calculation and selection of parameters such as power and speed of servo motors, as well as the calculation and selection of core components such as drivers and screws. During the design process, there will be no cost waste due to excessive margins, and it can also avoid the situation where the equipment requirements cannot be met due to the selection being too small.

[0059] The precise calculation of this application can ensure that the key core components such as servo motors, drivers, ball screws and bearing components will not have too much surplus when selecting them, resulting in cost waste, and can also avoid the situation where the equipment requirements cannot be met due to the selection being too small.

[0060] From the above description, it can be seen that the above embodiments of the present invention achieve the following technical effects:

[0061] The design method of the injection molding machine injection transmission mechanism of the present invention calculates the motor speed n1, motor stall torque T1 and motor instantaneous power P required during the injection process of the injection molding machine according to the structural parameters of the screw, the process parameters of the injection molding machine, the structural parameters of the transmission component and the transmission efficiency. 瞬 ; and according to the instantaneous power P of the motor 瞬 And the motor overload factor λ3 calculate the motor recommended power P 建议 When selecting a servo motor, the speed of the selected servo motor is greater than or equal to the motor speed n1, and the stall torque of the servo motor is greater than or equal to the motor stall torque T1, and the rated power of the servo motor is greater than or equal to the motor recommended power P 建议 Since the design method of the injection molding machine injection transmission mechanism is based on the motor speed n1, motor stall torque T1 and motor recommended power P 建议 The three calculation results are matched with the servo motor models in the servo motor sample, and the servo motor that meets the conditions is selected. The design process is more accurate and will not cause cost waste due to excessive surplus. It can also avoid the situation where the selected model is too small to meet the equipment requirements, thereby ensuring the reliability of the servo motor during use.

[0062] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. For those skilled in the art, the present invention may have various modifications and variations. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention shall be included in the protection scope of the present invention.

Claims

1. A design method for an injection molding machine injection transmission mechanism, wherein the injection molding machine comprises a screw and at least one injection transmission mechanism, wherein the injection transmission mechanism comprises a servo motor and a transmission assembly, wherein the servo motor drives the screw to move through the transmission assembly, wherein: The design method of the injection molding machine injection transmission mechanism includes: The motor speed n1, motor stall torque T1 and motor instantaneous power P required during the injection process of the injection molding machine are calculated according to the structural parameters of the screw, the process parameters of the injection molding machine, the structural parameters of the transmission assembly and the transmission efficiency. 瞬 ; According to the instantaneous power P of the motor 瞬 And the motor overload factor λ3 calculate the motor recommended power P 建议 ; According to the motor speed n1, the motor stall torque T1 and the motor recommended power P 建议 The servo motor is selected so that the speed of the selected servo motor is greater than or equal to the motor speed n1, the stall torque of the selected servo motor is greater than or equal to the motor stall torque T1, and the rated power of the selected servo motor is greater than or equal to the motor recommended power P 建议 ; The injection transmission mechanism also includes a driver, and the driver is communicatively connected with the servo motor; the design method of the injection transmission mechanism of the injection molding machine includes: Get the torque constant k and rated torque T of the selected servo motor when the temperature rises by 100°C N , Maximum torque T max , Rated current I 额 , Maximum current I max And the servo motor rated speed n 额 ; According to the maximum torque T2 of the servo motor during the injection process, the torque constant k, the rated torque T N , the maximum torque T max , the rated current I 额 , the maximum current I max Calculate the maximum current I that the driver will reach during the operation of the servo motor 驱动器max ; and meets: η max is the maximum torque efficiency; η 额 is the rated torque efficiency, based on the maximum current I 驱动器max The driver is selected so that the maximum current of the selected driver is greater than or equal to the maximum current I of the driver. 驱动器max .

2. The design method of the injection molding machine injection transmission mechanism according to claim 1 is characterized in that: The transmission assembly includes a synchronous pulley assembly and a ball screw, the synchronous pulley assembly includes a first pulley, a second pulley and a synchronous belt, the synchronous belt is sleeved on the first pulley and the second pulley, the motor is connected to the first pulley, the second pulley is connected to the screw of the ball screw, and the screw nut of the ball screw is connected to the screw; the method for calculating the motor speed n1 required during the injection process of the injection molding machine according to the structural parameters of the screw, the process parameters of the injection molding machine, the structural parameters of the transmission assembly and the transmission efficiency includes: The motor speed n1 is calculated according to the maximum injection speed v, the lead S of the screw and the pulley transmission ratio i; wherein, Calculating the pulley transmission ratio i according to the first pulley tooth number Z1 and the second pulley tooth number Z2; 3. The design method of the injection molding machine injection transmission mechanism according to claim 1 is characterized in that: The transmission assembly includes a synchronous pulley assembly and a ball screw, the synchronous pulley assembly includes a first pulley, a second pulley and a synchronous belt, the synchronous belt is sleeved on the first pulley and the second pulley, the motor is connected to the first pulley, the second pulley is connected to the screw of the ball screw, and the screw nut of the ball screw is connected to the screw; the injection molding machine also includes a support seat, the screw is penetrated by the support seat, a bearing assembly is arranged between the screw and the support seat, and the bearing assembly is sleeved on the screw; the method for calculating the motor stall torque T1 required during the injection process of the injection molding machine according to the structural parameters of the screw, the process parameters of the injection molding machine, the structural parameters of the transmission assembly and the transmission efficiency includes: According to the calculation formula Calculate the motor stall torque T1; wherein d is the diameter of the screw, S is the lead of the screw, P1 is the maximum holding pressure, i is the pulley transmission ratio; η1 is the belt transmission efficiency, η2 is the screw transmission efficiency, and η3 is the bearing transmission efficiency; Calculating the pulley transmission ratio i according to the first pulley tooth number Z1 and the second pulley tooth number Z2; 4. The design method of the injection molding machine injection transmission mechanism according to claim 1 is characterized in that: The transmission assembly includes a synchronous pulley assembly and a ball screw, the synchronous pulley assembly includes a first pulley, a second pulley and a synchronous belt, the synchronous belt is sleeved on the first pulley and the second pulley, the motor is connected to the first pulley, the second pulley is connected to the screw of the ball screw, and the screw nut of the ball screw is connected to the screw; the injection molding machine also includes a support seat, the screw is passed through the support seat, a bearing assembly is arranged between the screw and the support seat, and the bearing assembly is sleeved on the screw; the instantaneous power P of the motor required during the injection process of the injection molding machine is calculated according to the structural parameters of the screw, the process parameters of the injection molding machine, the structural parameters of the transmission assembly and the transmission efficiency 瞬 The methods include: According to the calculation formula Calculate the instantaneous power P of the motor 瞬 ; Wherein, d is the diameter of the screw, η1 is the belt transmission efficiency, η2 is the screw transmission efficiency, η3 is the bearing transmission efficiency, n is the number of the screws, P is the maximum injection pressure, v is the maximum injection speed, and λ2 is the coordination coefficient of injection speed and pressure.

5. The design method of the injection molding machine injection transmission mechanism according to claim 1 is characterized in that: According to the instantaneous power P of the motor 瞬 And the motor overload factor λ3 calculate the motor recommended power P 建议 The methods include: According to the calculation formula Calculate the recommended motor power P 建议 .

6. The design method of the injection molding machine injection transmission mechanism according to claim 1 is characterized in that: According to the maximum torque T2 of the servo motor during the injection process, the torque constant k, the rated torque T N , the maximum torque T max , the rated current I 额 , the maximum current I max Calculate the maximum current I that the driver will reach during the operation of the servo motor 驱动器max The methods include: According to the calculation formula Calculate the maximum driver current I 驱动器max ; in, P is the maximum injection pressure, and P1 is the maximum holding pressure; η max is the maximum torque efficiency, 7. The design method of the injection molding machine injection transmission mechanism according to claim 1 is characterized in that: The design method of the injection molding machine injection transmission mechanism includes: Get the voltage constant K of the selected driver e , torque constant K t , line resistance R w , pole number PN and line inductance Lw; The selected driver is verified, and the verification conditions are: Wherein, Vmax is the maximum voltage of the servo motor during operation, E min is the minimum main voltage of the driver; ω pk is the maximum angular velocity of the servo motor, C max is the maximum torque of the servo motor, Cw max =T2; If the above verification conditions are met, it indicates that the selected driver meets the working condition requirements. If the conditions are not met, a higher-speed servo motor needs to be selected to match a larger driver driving current.

8. The design method of the injection molding machine injection transmission mechanism according to any one of claims 1 to 5, characterized in that: The transmission assembly includes a ball screw, the servo motor is connected to the screw of the ball screw, and the screw nut of the ball screw is connected to the screw; the design method of the injection molding machine injection transmission mechanism also includes: The maximum axial force F of the screw is calculated according to the diameter d of the screw, the number n of the screws and the maximum injection pressure P; The ball screw is selected according to the maximum axial force F of the screw, so that the maximum axial force of the selected ball screw is greater than or equal to the maximum axial force F of the screw.

9. The design method of the injection molding machine injection transmission mechanism according to claim 8, characterized in that: The method for calculating the maximum axial force F of the screw according to the diameter d of the screw, the number n of the screws and the maximum injection pressure P includes: According to the calculation formula Calculate the maximum axial force F of the screw.

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