Electric mold opening and closing structure and injection molding machine
By using the motor, lead screw, and toggle lever force amplification mechanism in the electric mold opening and closing structure, the problems of energy loss and insufficient mold closing force in the hydraulic mold opening and closing structure are solved, realizing efficient and energy-saving injection molding production.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- NINGBO MYTAO PRECISION MASCH CO LTD
- Filing Date
- 2025-05-29
- Publication Date
- 2026-04-28
AI Technical Summary
The hydraulic mold opening and closing structure of existing injection molding machines results in high heat generation of hydraulic oil, large power loss, low transmission efficiency, and insufficient mold closing force when the driving force is large, leading to low production efficiency and mold damage.
The electric mold opening and closing structure utilizes a motor, lead screw, and toggle lever force amplification mechanism to efficiently convert the motor's rotary motion into the linear motion of the moving mold plate. Combined with the toggle lever force amplification mechanism, it provides greater clamping force and reduces energy loss.
It improves the quality and production efficiency of injection molded products, reduces energy consumption and equipment costs, has high transmission efficiency, low mechanical friction coefficient, and realizes intelligent clamping force control.
Smart Images
Figure CN224170397U_ABST
Abstract
Description
Technical Field
[0001] This utility model relates to the field of injection molding machine technology, and more specifically, to an electric mold opening and closing structure and an injection molding machine. Background Technology
[0002] When the injection molding machine's moving platen performs the opening and closing action, it needs to perform reciprocating linear motion on the tie rod. Some existing injection molding machines use a hydraulic power system and hydraulic cylinders as the power mechanism for the linear back-and-forth motion of the mold opening and closing. During the mold opening and closing process, the required driving force is large, which leads to high heat generation of the hydraulic oil during operation, large power loss, and low transmission efficiency. This results in a decrease in the power of the hydraulic system (i.e., insufficient mold closing force), which in turn leads to slow or stuck mold closing action, low production efficiency, and insufficient mold closing force can also cause flash on the product or damage to the mold. Utility Model Content
[0003] To address at least one of the aforementioned problems, this utility model provides an electrically operated mold opening and closing structure, including a fixed mold plate, a movable mold plate, a tail plate, and a driving mechanism for driving the movable mold plate to slide. The driving mechanism includes a motor, a lead screw, and a lead screw nut assembly threadedly connected to the lead screw. The lead screw is rotatably mounted on the tail plate, and the motor drives the lead screw to rotate. A toggle lever force amplification mechanism is provided between the tail plate and the movable mold plate. The toggle lever force amplification mechanism includes an active toggle lever and a driven toggle lever assembly. One end of the driven toggle lever assembly is hinged to the tail plate, and the other end of the driven toggle lever assembly... The active elbow is hinged to the moving template, and the driven elbow assembly includes several driven elbows hinged end to end. One end of the active elbow is hinged to one of the driven elbows, and the other end of the active elbow is hinged to the screw nut assembly. This utility model's electric mold opening and closing structure drives the moving template to slide through a motor, screw, and other structures to complete the mold opening and closing actions. It efficiently converts the motor's rotational motion into the linear motion of the moving template, reducing energy loss and achieving high transmission efficiency. An elbow force amplification mechanism is provided, enabling greater clamping force under the same motor output power, thereby improving the quality of the injection molded product.
[0004] Optionally, the driven elbow includes a first driven elbow and a second driven elbow. One end of the driving elbow is hinged to the first driven elbow, one end of the first driven elbow is hinged to the tail plate, the other end of the first driven elbow is hinged to one end of the second driven elbow, and the end of the second driven elbow away from the first driven elbow is hinged to the moving template.
[0005] Optionally, a first hinge axis is provided at the hinge joint between the active elbow and the nut assembly, a second hinge axis is provided at the hinge joint between the active elbow and the first driven elbow, a third hinge axis is provided at the hinge joint between the first driven elbow and the tail plate, and a fourth hinge axis is provided at the hinge joint between the first driven elbow and the second driven elbow. The line connecting the third hinge axis and the fourth hinge axis is a straight line, and the first hinge axis and the second hinge axis are located on opposite sides of the straight line.
[0006] Optionally, the distance between the third hinge axis and the fourth hinge axis is a first length, the distance between the second hinge axis and the straight line is a second length, and the first length is 3 to 6 times the second length.
[0007] Optionally, the motor is fixedly mounted on the tail plate, one end of the lead screw is provided with a pulley, and a transmission belt is connected between the output shaft of the motor and the pulley.
[0008] Optionally, the lead screw assembly includes a lead screw block and a sliding frame fixedly connected to the lead screw block. The lead screw block is threadedly connected to the lead screw, and a bearing is provided between the lead screw and the tail plate.
[0009] Optionally, a guide rod is provided between the fixed template and the tail plate, the guide rod passing through the movable template, and the movable template slidingly engaging with the guide rod.
[0010] Optionally, a strain gauge force sensor is provided on the tail plate, and the strain gauge force sensor contacts the side of the tail plate away from the moving template, and the mechanical deformation of the tail plate is detected by the strain gauge force sensor.
[0011] Optionally, the electric mold opening and closing structure further includes a slide rail, which extends along the sliding direction of the moving template. The moving template is provided with a slider that slides and engages with the slide rail. The motor is a permanent magnet servo motor.
[0012] Compared to existing technologies, the electric mold opening and closing structure of this invention uses a motor, lead screw, and other structures to drive the moving mold plate to slide, thereby completing the mold opening and closing actions. It efficiently converts the motor's rotary motion into the linear motion of the moving mold plate, reducing energy loss and achieving high transmission efficiency. An elbow-type force amplification mechanism is included, providing greater clamping force with the same motor output power, thus improving the quality of the injection molded product. This mechanism also reduces the power requirement of the drive source, lowering energy consumption and equipment costs. The first and second hinge axes are located on opposite sides of the straight line, resulting in good force amplification. A slider on the moving mold plate slides smoothly with the slide rail, reducing the mechanical friction coefficient and minimizing energy loss during the movement of the moving mold plate, thus improving energy efficiency.
[0013] In addition, this utility model also provides an injection molding machine, including the above-mentioned electric mold opening and closing structure. This injection molding machine also has the beneficial effects of the above-mentioned electric mold opening and closing structure, which will not be described in detail here. Attached Figure Description
[0014] Figure 1 This is a perspective view of the electric opening and closing mold structure of this utility model;
[0015] Figure 2 for Figure 1 Enlarged view of section A in the middle;
[0016] Figure 3 This is a cross-sectional view of the electric mold opening and closing structure of this utility model;
[0017] Figure 4 for Figure 3 Enlarged view of section B;
[0018] Figure 5 for Figure 3 Enlarged view of section C;
[0019] Figure 6 This is a schematic diagram of the force amplification mechanism of the electric mold opening and closing structure of this utility model.
[0020] Figure 7 This is a schematic diagram of the first driven elbow of the electric mold opening and closing structure of this utility model;
[0021] Figure 8 This is a schematic diagram of the transmission belt portion of the electric mold opening and closing structure of this utility model;
[0022] The component names corresponding to the various labels in the figure are as follows: 1 is the fixed template, 2 is the moving template, 3 is the tail plate, 41 is the motor, 42 is the lead screw, 421 is the pulley, 43 is the lead screw assembly, 431 is the lead screw block, 432 is the sliding frame, 51 is the active elbow, 52 is the driven elbow, 521 is the first driven elbow, 522 is the second driven elbow, 61 is the first hinge axis, 62 is the second hinge axis, 63 is the third hinge axis, 64 is the fourth hinge axis, 65 is the linear actuator, 71 is the transmission belt, 72 is the bearing, 73 is the guide rod, 74 is the slide rail, 75 is the slider, and 8 is the strain gauge force sensor. Detailed Implementation
[0023] To make the above-mentioned objectives, features and advantages of this utility model more apparent and understandable, the specific embodiments of this utility model will be described in detail below with reference to the accompanying drawings.
[0024] In the description of this utility model, it should be understood that the terms "upper" and "lower" indicate the orientation or positional relationship based on the orientation or positional relationship when the product is in normal use.
[0025] The terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include at least one of that feature.
[0026] See Figures 1-8 This utility model provides an electrically operated mold opening and closing structure, including a fixed mold plate 1, a movable mold plate 2, a tail plate 3, and a driving mechanism for driving the movable mold plate 2 to slide. Both the fixed mold plate 1 and the tail plate 3 are connected to an external injection molding machine mounting base. The driving mechanism includes a motor 41, a lead screw 42, and a nut assembly 43 threadedly connected to the lead screw 42. The lead screw 42 is rotatably mounted on the tail plate 3. The motor 41 drives the lead screw 42 to rotate. A toggle lever force amplification mechanism is provided between the tail plate 3 and the movable mold plate 2. The toggle lever force amplification mechanism includes an active toggle lever 51 and a driven toggle lever assembly. One end of the driven toggle lever assembly is hinged to the tail plate 3, and the other end is hinged to the movable mold plate 2. The rod assembly includes several driven elbows 52 hinged at both ends. One end of the driving elbow 51 is hinged to one of the driven elbows 52, and the other end of the driving elbow 51 is hinged to the screw nut assembly 43. The elbow force amplification mechanism can increase the driving force of the motor 41 on the moving platen 2, thereby increasing the clamping force. The electric mold opening and closing structure of this utility model drives the moving platen to slide through the motor, screw and other structures to complete the mold opening and clamping actions, efficiently converting the rotational motion of the motor into the linear motion of the moving platen, reducing energy loss and achieving high transmission efficiency. The elbow force amplification mechanism provides a greater clamping force under the same motor output power, thereby improving the quality of the injection molded product.
[0027] See Figure 3 , Figure 4 , Figure 6 and Figure 7The driven elbow 52 includes a first driven elbow 521 and a second driven elbow 522. One end of the driving elbow 51 is hinged to the first driven elbow 521, one end of the first driven elbow 521 is hinged to the tail plate 3, and the other end of the first driven elbow 521 is hinged to one end of the second driven elbow 522. The end of the second driven elbow 522 away from the first driven elbow 521 is hinged to the moving template 2. The elbow force amplification mechanism adopts an inward-folding type, which occupies less external space during movement and is suitable for installation in space-constrained environments. By setting the elbow force amplification mechanism, the power requirement of the drive source (in this embodiment, a motor) can be reduced, thus reducing energy consumption and equipment costs. A first hinge axis 61 is provided at the hinge point between the driving elbow 51 and the nut assembly 43. The driving elbow 51 and the first driven elbow 521 are connected by a first hinge axis 61. A second hinge axis 62 is provided at the hinge joint of the movable elbow 521, a third hinge axis 63 is provided at the hinge joint of the first driven elbow 521 and the tail plate 3, and a fourth hinge axis 64 is provided at the hinge joint of the first driven elbow 521 and the second driven elbow 522. The line connecting the third hinge axis 63 and the fourth hinge axis 64 is a straight line 65. The first hinge axis 61 and the second hinge axis 62 are located on both sides of the straight line 65, resulting in a good force amplification effect. In the past, the second hinge axis 62 was located or approximately located on the straight line 65 in the elbow force amplification mechanism. In this embodiment, the second hinge axis 62 is set on one side of the straight line 65 to increase the distance between the second hinge axis 62 and the fourth hinge axis 64, increase the lever arm during operation, improve the force amplification effect, and further improve the clamping force.
[0028] See Figure 3 and Figure 4 The distance between the third hinge axis 63 and the fourth hinge axis 64 is the first length, and the distance between the second hinge axis 62 and the straight line 65 is the second length. The first length is 3 to 6 times the second length. In this embodiment, the first length is 4.5 times the second length, which has a good force amplification effect. The multiple of the first length to the second length is set appropriately. If the multiple is set too small, it will lead to a large structural volume. If the multiple is set too large, it will lead to a poor force amplification effect. In this embodiment, there are two symmetrically arranged active elbow rods 51 and driven elbow rod assemblies.
[0029] See Figure 1 , Figure 3 , Figure 5 and Figure 8The motor 41 is fixedly mounted on the tail plate 3. One end of the lead screw 42 is provided with a pulley 421. A transmission belt 71 is connected between the output shaft of the motor 41 and the pulley 421. The transmission structure is simple, the production cost is low, and the transmission is reliable. The lead screw assembly 43 includes a lead screw block 431 and a sliding frame 432 fixedly connected to the lead screw block 431. The lead screw block 431 is threadedly connected to the lead screw 42. A bearing 72 is provided between the lead screw 42 and the tail plate 3. The lead screw 42 rotates smoothly, improving the transmission efficiency. In this embodiment, the lead screw block 431 is a ball screw block, which further reduces power loss.
[0030] See Figure 1 , Figure 2 and Figure 8 A guide rod 73 is provided between the fixed template 1 and the tail plate 3, passing through the moving template 2. The moving template 2 slides smoothly with the guide rod 73, ensuring smooth operation during mold opening and closing. A strain gauge force sensor 8 is provided on the tail plate 3, contacting the side of the tail plate 3 away from the moving template 2. The strain gauge force sensor 8 detects the mechanical deformation of the tail plate 3, and the clamping force is detected by detecting the mechanical deformation of the tail plate 3. The detection principle is as follows: In this embodiment, the strain gauge force sensor 8 detects the mechanical deformation of the clamping tail plate as 0-0.5mm / m, corresponding to an output voltage of 0-10V. The controller of the injection molding machine converts the 0-10V voltage into machine voltage. The clamping force sensor can be set from 0 to the rated clamping force (e.g., 100T) to achieve functions such as clamping force monitoring. The clamping force sensor can also extend the following functions of the injection molding machine, such as: 1. Automatic clamping force calibration function to overcome the increase in clamping force after mold thermal expansion; in the fully automatic production process, the clamping force change value is set to 5%; when the mold thermally expands and the clamping force increases by more than 5%, the machine automatically adjusts the mold thickness position and corrects the clamping force; 2. Overcoming product defects caused by poor mold venting, for example: with a rated clamping force of 100T, the clamping force can be pre-clamped at 30% (30T) for injection, and after the plastic raw material is filled, a second clamping force of 100% (100T) is applied.
[0031] See Figure 1 and Figure 2The electric mold opening and closing structure also includes a slide rail 74. Two slide rails 74 are arranged in parallel and are fixedly connected to the external injection molding machine mounting base. The slide rail 74 extends along the sliding direction of the moving platen 2. The moving platen 2 is provided with a slider 75 that slides and engages with the slide rail 74. The moving platen 2 slides smoothly, reducing the mechanical friction coefficient and making the energy loss of the motor during the movement of the moving platen lower and more energy-efficient. The motor 41 is a permanent magnet servo motor. The clamping force detected by the strain gauge force sensor 8 is transmitted to the permanent magnet servo motor, thereby realizing closed-loop control of the torque of the permanent magnet servo motor. This makes the mold opening and closing structure digital and intelligent. It also enables the permanent magnet servo motor to intelligently adjust the torque output when the mold is thermally expanded, controlling the electric clamping device to output a constant clamping force.
[0032] The electric mold opening and closing structure of this utility model drives the moving mold plate to slide through a motor, lead screw, and other structures to complete the mold opening and closing actions. It efficiently converts the rotational motion of the motor into the linear motion of the moving mold plate, reducing energy loss and achieving high transmission efficiency. An elbow lever force amplification mechanism is provided, enabling greater clamping force with the same motor output power, thereby improving the quality of injection molded products. The elbow lever force amplification mechanism also reduces the power requirement of the drive source, lowering energy consumption and equipment costs. The first and second hinge axes are located on opposite sides of the straight line, resulting in good force amplification. A slider that slides smoothly with the slide rail on the moving mold plate ensures smooth sliding, reduces the coefficient of mechanical friction, and minimizes energy loss during the movement of the moving mold plate, making it more energy-efficient.
[0033] In addition, this utility model also provides an injection molding machine, including the above-mentioned electric mold opening and closing structure. This injection molding machine also has the beneficial effects of the above-mentioned electric mold opening and closing structure, which will not be described in detail here.
[0034] In the description of this disclosure, it should be understood that the terms "upper", "lower", "bottom", "inner", "outer", "circumferential", etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings, and are only for the convenience of describing this disclosure and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of this disclosure.
[0035] Furthermore, the terms "first," "second," etc., are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Thus, a feature defined with "first," "second," etc., may explicitly or implicitly include at least one of that feature. In the description of this disclosure, "a plurality of" means at least two, such as two, three, etc., unless otherwise explicitly specified.
[0036] In this disclosure, unless otherwise expressly specified and limited, the terms "installation," "connection," etc., should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; they can refer to a mechanical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication of two components or the interaction between two components, unless otherwise expressly limited. Those skilled in the art can understand the specific meaning of the above terms in this disclosure according to the specific circumstances.
[0037] In this disclosure, unless otherwise expressly specified and limited, the first feature "on" or "below" the second feature may be in direct contact with the first feature or in indirect contact with the first feature through an intermediate medium.
[0038] It should be noted that when a component is described as being "set on" another component, it can be directly on the other component or there may be an intervening component. When a component is described as "connected to another component," it can be directly connected to the other component or there may be an intervening component. Furthermore, when a component is described as being "fixedly connected" to another component, the connection can be detachable or non-detachable, such as through socketing, snap-fitting, integral molding, welding, etc., which are achievable in conventional technologies and will not be elaborated upon here.
[0039] The technical features of the above embodiments can be combined in any way. For the sake of brevity, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.
Claims
1. An electrically operated mold opening and closing structure, characterized in that, The system includes a fixed template (1), a movable template (2), a tail plate (3), and a driving mechanism for driving the movable template (2) to slide. The driving mechanism includes a motor (41), a lead screw (42), and a lead screw assembly (43) threadedly connected to the lead screw (42). The lead screw (42) is rotatably mounted on the tail plate (3). The motor (41) drives the lead screw (42) to rotate. An elbow lever is provided between the tail plate (3) and the movable template (2) to amplify the force. The mechanism includes an active elbow (51) and a driven elbow assembly. One end of the driven elbow assembly is hinged to the tail plate (3), and the other end of the driven elbow assembly is hinged to the moving template (2). The driven elbow assembly includes several driven elbows (52) that are hinged at both ends. One end of the active elbow (51) is hinged to one of the driven elbows (52), and the other end of the active elbow (51) is hinged to the nut assembly (43).
2. The electrically operated mold opening and closing structure according to claim 1, characterized in that, The driven elbow (52) includes a first driven elbow (521) and a second driven elbow (522). One end of the driving elbow (51) is hinged to the first driven elbow (521). One end of the first driven elbow (521) is hinged to the tail plate (3). The other end of the first driven elbow (521) is hinged to one end of the second driven elbow (522). The end of the second driven elbow (522) away from the first driven elbow (521) is hinged to the moving template (2).
3. The electrically operated mold opening and closing structure according to claim 2, characterized in that, A first hinge axis (61) is provided at the hinge joint between the active elbow (51) and the nut assembly (43). A second hinge axis (62) is provided at the hinge joint between the active elbow (51) and the first driven elbow (521). A third hinge axis (63) is provided at the hinge joint between the first driven elbow (521) and the tail plate (3). A fourth hinge axis (64) is provided at the hinge joint between the first driven elbow (521) and the second driven elbow (522). The line connecting the third hinge axis (63) and the fourth hinge axis (64) is a straight line (65). The first hinge axis (61) and the second hinge axis (62) are located on both sides of the straight line (65).
4. The electrically operated mold opening and closing structure according to claim 3, characterized in that, The distance between the third hinge axis (63) and the fourth hinge axis (64) is a first length, and the distance between the second hinge axis (62) and the straight line (65) is a second length. The first length is 3 to 6 times the second length.
5. The electrically operated mold opening and closing structure according to claim 1, characterized in that, The motor (41) is fixedly mounted on the tail plate (3), and a pulley (421) is provided at one end of the lead screw (42). A transmission belt (71) is connected between the output shaft of the motor (41) and the pulley (421).
6. The electrically operated mold opening and closing structure according to claim 1, characterized in that, The lead screw assembly (43) includes a lead screw block (431) and a sliding frame (432) fixedly connected to the lead screw block (431). The lead screw block (431) is threadedly connected to the lead screw (42), and a bearing (72) is provided between the lead screw (42) and the tail plate (3).
7. The electrically operated mold opening and closing structure according to claim 1, characterized in that, A guide rod (73) is provided between the fixed template (1) and the tail plate (3). The guide rod (73) passes through the moving template (2), and the moving template (2) and the guide rod (73) are in sliding cooperation.
8. The electrically operated mold opening and closing structure according to claim 1, characterized in that, A strain gauge force sensor (8) is provided on the tail plate (3). The strain gauge force sensor (8) contacts the side of the tail plate (3) away from the moving template (2) and detects the mechanical deformation of the tail plate (3) through the strain gauge force sensor (8).
9. The electrically operated mold opening and closing structure according to any one of claims 1-8, characterized in that, The electric mold opening and closing structure also includes a slide rail (74), which extends along the sliding direction of the moving template (2). The moving template (2) is provided with a slider (75) that slides and engages with the slide rail (74). The motor (41) is a permanent magnet servo motor.
10. An injection molding machine, characterized in that, Includes the electrically operated mold opening and closing structure as described in any one of claims 1-9.