An all-electric injection molding machine clamping device

Abstract

The utility model discloses a kind of full-electric injection molding machine mold locking devices, it is related to injection molding equipment technical field, including tail plate, movable template, fixed template and the several guide pillars of connecting movable template and fixed template, further include: ball screw mechanism, including screw, support seat, retainer, crosshead and several rollers, screw is horizontally through tail plate and is rotatably installed in tail plate interior by support seat, roller is set several both ends are fixed in position by retainer, nut is set on the outside of roller, roller and nut are threadedly engaged, roller and screw are threadedly engaged;Inclined five-point double-curved elbow mechanism is used to connect tail plate, movable template and crosshead;Driving assembly is used to drive screw to rotate, adopt planetary roller screw mechanism to replace traditional ball screw transmission system, planetary roller screw is engaged by the composite of multiple rollers and screw, nut, change single-point contact into multipoint contact, make load evenly distributed.

Description

Technical Field

[0001] This utility model relates to the field of injection molding equipment technology, specifically to a clamping device for an all-electric injection molding machine. Background Technology

[0002] All-electric injection molding machines are injection molding equipment where all units are driven by electricity. They can turn thermoplastic or thermosetting plastics into various precision plastic products through molds. They have outstanding advantages such as high efficiency, precision, energy saving and environmental protection, and are widely used in high-requirement industries such as automobiles, electronics, and medical.

[0003] In my country's injection molding machine market, hydraulic products still dominate, but they suffer from high energy consumption, high emissions, and low levels of green technology. To adapt to the green development trend of the plastics industry and respond to the national strategies of "carbon neutrality" and "carbon peaking," the demand for electric and hybrid injection molding machines continues to rise, with all-electric injection molding machines showing particularly broad market prospects.

[0004] However, as all-electric injection molding machines develop towards larger tonnage units, their clamping units face significant technical bottlenecks. Traditional clamping mechanisms typically rely on ball screw drives, but limited by the rated dynamic load capacity of the ball screws, they struggle to meet the high clamping force requirements of large tonnage machines. Currently, mainstream large-tonnage solutions often employ hybrid electric / hydraulic or "dual (multi) drive" structures. The former has inherent drawbacks in terms of energy saving and environmental protection, while the latter introduces problems such as complex servo synchronous control and increased costs. Therefore, a new transmission structure suitable for the clamping unit of large-tonnage all-electric injection molding machines is urgently needed to overcome load limitations and achieve truly efficient, stable, and environmentally friendly high-performance clamping. Utility Model Content

[0005] The purpose of this invention is to overcome the problems in the prior art and provide a clamping device for an all-electric injection molding machine. It solves the problem that the existing transmission structure of the clamping unit and the rated dynamic load of the ball screw cannot meet the large clamping force.

[0006] This utility model provides a clamping device for an all-electric injection molding machine, including a tail plate, a moving platen, a fixed platen, and several guide pillars connecting the moving platen and the fixed platen. Each guide pillar has a threaded post at its tail end, and the threaded posts threaded through the tail plate. The device also includes: a ball screw mechanism, comprising a screw, a support, a cage, a crosshead, a bearing, and several rollers. The screw horizontally passes through the tail plate and is rotatably mounted inside the tail plate via the support. The screw is connected to the support via the bearing. Several rollers are provided, with both ends fixed in position by the cage. Nuts are fitted on the outer sides of the rollers, and the rollers and nuts are threadedly engaged. The rollers are also threadedly engaged with the screw. The crosshead is fixedly connected to the outer side of the nut. A five-point double-crank toggle mechanism is used to connect the tail plate, the moving platen, and the crosshead. A drive assembly is used to drive the screw to rotate.

[0007] Preferably, the rollers are provided in groups of eight.

[0008] Preferably, the roller is provided with spur gears at both ends, and the nut is provided with gear rings at both ends that mate with the spur gears. Preferably, the ball screw mechanism further includes the bearing, end cap, and lock nut, wherein the bearing is positioned between the screw and the support base and is securely connected by the end cap and lock nut.

[0009] Preferably, the oblique five-point double-curved elbow mechanism includes four front connecting rods, four rear connecting rods, and two first connecting rods arranged symmetrically in the upper and lower parts. The front connecting rods and rear connecting rods, the front connecting rods and the moving template, the rear connecting rods and the tail plate, and the rear connecting rods and the first connecting rods are all hinged by pins.

[0010] Preferably, the drive assembly includes a servo motor, a first mold-locking pulley, and a second mold-locking pulley. The servo motor is fixedly mounted on the tail plate via a mold-locking motor plate. The output shaft of the servo motor is fixedly connected to the first mold-locking pulley, and the lead screw is fixedly connected to the second mold-locking pulley. The first mold-locking pulley and the second mold-locking pulley are connected by a synchronous belt.

[0011] Preferably, an adjustment block is fixedly installed at the bottom of the moving template, and a pair of sliders are fixedly connected to the bottom of the adjustment block. A linear guide rail is provided on the base of the injection molding machine, and the pair of sliders are slidably disposed within the linear guide rail.

[0012] Preferably, each of the guide posts is fixedly connected to a threaded post threaded through the tail plate at the end away from the fixed template. A first mold-adjusting gear ring is provided at the center of the tail plate. The first mold-adjusting gear ring is rotatably mounted on the tail plate. A second mold-adjusting gear is threadedly sleeved on each of the threaded posts. The second mold-adjusting gears mesh with the first mold-adjusting gear ring. The first mold-adjusting gear is connected to a mold-adjusting motor via an idler gear on one side of the second mold-adjusting gear.

[0013] Compared with the prior art, the beneficial effects of this utility model are: The planetary roller screw mechanism replaces the traditional ball screw transmission system. Through the combined meshing of multiple rollers with the screw and nut, the planetary roller screw transforms single-point contact into multi-point contact, resulting in a more even load distribution. Its rated dynamic load is more than 15 times that of a traditional ball screw, easily handling clamping forces exceeding 300 tons. Simultaneously, this structure retains the inherent energy-saving and environmentally friendly characteristics of all-electric injection molding machines, completely avoiding the hydraulic oil pollution and energy waste problems associated with hybrid hydraulic systems. It also avoids the servo synchronization challenges and high costs inherent in dual-drive or multi-drive systems. Attached Figure Description

[0014] Figure 1 This is a schematic diagram of the overall structure of this utility model; Figure 2 This is a partial structural schematic diagram of the present invention; Figure 3 This is a schematic diagram of the ball screw mechanism of this utility model.

[0015] Explanation of reference numerals in the attached drawings: 1. Fixed template; 2. Guide post; 3. Moving template; 4. Five-point double-curved elbow mechanism; 41. Front connecting rod; 42. Pin; 43. Rear connecting rod; 44. First connecting rod; 5. Ball screw mechanism; 51. Support seat; 52. Cage; 53. Crosshead; 54. Roller; 55. Bearing; 56. End cap; 57. Locking nut; 6. Drive assembly; 61. Servo motor; 62. First mold-locking pulley; 63. Second mold-locking pulley; 64. Mold-locking motor plate; 7. Adjusting block; 8. Slider; 9. Linear guide rail; 10. First mold-adjusting gear ring; 11. First mold-adjusting gear; 12. Second mold-adjusting gear; 13. Idler wheel; 14. Mold-adjusting motor; 15. Synchronous belt; 16. Tail plate. Detailed Implementation

[0016] The following is in conjunction with the appendix Figures 1-3To make the objectives, technical solutions, and advantages of the embodiments of this utility model clearer, the technical solutions of the embodiments of this utility model will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some, not all, of the embodiments of this utility model. Based on the described embodiments of this utility model, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this utility model. Unless otherwise defined, the technical or scientific terms used herein should have the ordinary meaning understood by those skilled in the art to which this utility model pertains.

[0017] The terms "first," "second," and similar words used in this utility model patent application specification and claims do not indicate any order, quantity, or importance, but are merely used to distinguish different components. Terms such as "comprising" or "including" mean that the element or object preceding the word encompasses the elements or objects listed after the word and their equivalents, without excluding other elements or objects. Terms such as "inner," "outer," "upper," "lower," "far," "near," "front," and "rear" are only used to indicate relative positional relationships. When the absolute position of the described object changes, the relative positional relationship may also change accordingly. The drawings in this utility model are not strictly drawn to scale; the specific dimensions and quantity of each structure can be determined according to actual needs. The drawings described in this utility model are only structural schematic diagrams.

[0018] This utility model provides a mold clamping device for a fully electric injection molding machine, such as... Figures 1-3 As shown, the assembly includes a tail plate, a moving template, a fixed template, and several guide pillars connecting the moving template and the fixed template. Each guide pillar has a threaded post at its end, and the threaded posts threaded through the tail plate. The assembly also includes: a ball screw mechanism, comprising a screw, a support base, a cage, a crosshead, a bearing, and several rollers. The screw horizontally passes through the tail plate and is rotatably mounted inside the tail plate via the support base. The screw is connected to the support base via the bearing. Several rollers are provided, with both ends fixed in position by the cage. Nuts are fitted on the outer sides of the rollers, and the rollers and nuts are threadedly engaged. The rollers are threadedly engaged with the screw, and the crosshead is fixedly connected to the outer side of the nut. A five-point double-crank toggle mechanism is used to connect the tail plate, the moving template, and the crosshead. A drive assembly is used to drive the screw to rotate.

[0019] In this embodiment, a planetary roller screw mechanism is used to replace the traditional ball screw transmission system. The planetary roller screw, through the combined meshing of multiple rollers with the screw and nut, transforms single-point contact into multi-point contact, resulting in a more even load distribution. Its rated dynamic load is more than 15 times that of a traditional ball screw, easily handling clamping forces exceeding 300 tons. Simultaneously, this structure maintains the inherent energy-saving and environmentally friendly characteristics of an all-electric injection molding machine, completely avoiding the hydraulic oil pollution and energy waste problems associated with hybrid oil-electric solutions. It also avoids the servo synchronization difficulties and high costs inherent in dual-drive or multi-drive solutions.

[0020] Preferably, as shown in 3, there are 8 rollers; the rollers 54 are provided with spur gears at both ends, and the nut 62 is provided with gear rings that cooperate with the spur gears at both ends; the ball screw mechanism 5 also includes a bearing, an end cover and a locking nut, the bearing is placed between the screw and the support seat and is securely connected by the end cover and the locking nut.

[0021] In this embodiment, the use of eight rollers is the optimal configuration after mechanical calculations and optimization, achieving an optimal balance between load-bearing capacity, smooth motion, and manufacturing cost. Each roller maintains a precise circumferential position through cages at both ends, forming a stable planetary gear train. During operation, all eight rollers simultaneously mesh with the screw and nut, distributing the enormous axial load across eight contact points, greatly reducing stress concentration at individual contact points and significantly improving fatigue life and reliability. The combination of bearings, end caps, and locking nuts constitutes the precision support system of the planetary roller screw. The four-unit angular contact ball bearings can simultaneously withstand radial and axial forces, providing stable rotational support for the screw and ensuring transmission accuracy. The end caps not only serve as dust seals but, more importantly, control the bearing preload through precise machining dimensions, eliminating axial backlash and improving transmission rigidity. The locking nuts, in conjunction with the anti-loosening device, reliably lock the bearing position, preventing loosening under frequent forward and reverse rotation conditions.

[0022] Preferred, such as Figures 1-2 As shown, the oblique five-point double-curved elbow mechanism includes four front connecting rods, four rear connecting rods, and two first connecting rods arranged symmetrically in the upper and lower parts. The front connecting rods and rear connecting rods, the front connecting rods and the moving template, the rear connecting rods and the tail plate, and the rear connecting rods and the first connecting rods are all hinged by pins.

[0023] In this embodiment, the four front connecting rods and four rear connecting rods arranged symmetrically form a stable force transmission framework, while the two first connecting rods play a crucial role in force amplification and motion conversion. All connecting rods are hinged together by precision pins, forming a multi-degree-of-freedom planar mechanism system. This allows the mechanism to generate a huge force amplification ratio during mold closing, amplifying the relatively small thrust transmitted from the servo motor through the planetary roller screw into a clamping force sufficient to meet the requirements of large-tonnage injection molding. At the same time, the oblique five-point design ensures that the mechanism occupies less space when the mold is open, and rapidly expands to generate a huge clamping force when the mold is closed, with a smooth and reliable motion trajectory.

[0024] Preferred, such as Figures 1-2 As shown, the drive assembly includes a servo motor, a first mold-locking pulley, and a second mold-locking pulley. The servo motor is fixedly mounted on the tail plate via a mold-locking motor plate. The output shaft of the servo motor is fixedly connected to the first mold-locking pulley, and the lead screw is fixedly connected to the second mold-locking pulley. The first mold-locking pulley and the second mold-locking pulley are connected by a synchronous belt.

[0025] In this embodiment, the servo motor has the advantages of fast response, high control precision and high efficiency. It can accurately control the mold closing speed, position and pressure. The transmission ratio of the first mold clamping pulley and the second mold clamping pulley is carefully designed to ensure sufficient output torque and enable the servo motor to work in the high-efficiency speed range. The entire drive assembly is firmly installed on the tail plate through the mold clamping motor plate to form a compact overall structure.

[0026] Preferred, such as Figures 1-2 As shown, an adjustment block is fixedly installed at the bottom of the moving template, and a pair of sliders are fixedly connected to the bottom of the adjustment block. A linear guide rail is provided on the base of the injection molding machine, and the pair of sliders are slidably set in the linear guide rail.

[0027] In this embodiment, the slider at the bottom of the moving template works in conjunction with the linear guide rail to form a precise guide, which plays a crucial role in ensuring mold closing accuracy and extending equipment life. The symmetrical arrangement of a pair of sliders ensures that the moving template maintains good levelness and straightness during movement, preventing mold wear and product flash caused by skew.

[0028] Preferred, such as Figures 1-2 As shown, several guide posts are fixedly connected to threaded posts with threads passing through the tail plate at the ends away from the fixed template. A first mold adjustment gear ring is provided at the center of the tail plate. The first mold adjustment gear ring is rotatably installed on the tail plate. Several threaded posts are threaded with second mold adjustment gears. Several second mold adjustment gears mesh with the first mold adjustment gear ring. The first mold adjustment gear is meshed with the first mold adjustment gear on one side through an idler gear. The first mold adjustment gear is connected to a mold adjustment motor.

[0029] In this embodiment, the mold adjustment motor adopts a three-phase asynchronous motor to provide stable power output. Through multi-stage transmission of the first mold adjustment gear, idler gear, first mold adjustment gear ring, and second mold adjustment gear, the four mold adjustment nuts are finally driven to rotate synchronously, ensuring the synchronicity of each mold adjustment point and avoiding tail plate skewing and uneven force on the guide post caused by asynchrony. The structure of the first mold adjustment gear ring simultaneously driving the four second mold adjustment gears ensures the uniform distribution of mold adjustment force, so that the tail plate moves smoothly and the mold thickness is accurately adjusted. The entire mold adjustment process can be precisely controlled by the control system, realizing digital setting and automated operation, which greatly improves the efficiency and accuracy of mold adjustment and reduces the human error and labor intensity of traditional manual mold adjustment.

[0030] The method of using the all-electric injection molding machine clamping device of this utility model is as follows: According to the mold thickness requirements, the mold adjustment motor is started, and the first mold adjustment gear ring is driven to rotate through the gear transmission system, which drives the four second mold adjustment gears to rotate synchronously. The second mold adjustment gears mesh with the threaded column at the tail end of the guide post, pushing the tail plate to move along the guide axis, and precisely adjusting the distance between the moving mold plate and the fixed mold plate until the predetermined mold thickness is achieved. During the mold adjustment process, the linear guide rail ensures the smoothness and straightness of the movement of the moving mold plate.

[0031] After mold adjustment, the servo motor is started, driving the planetary roller screw to rotate via synchronous belt transmission. The rotation of the screw drives eight rollers to perform planetary motion. The rollers engage with the nut, pushing the nut and crosshead forward in a linear motion. The crosshead drives the inclined five-point double-crank toggle mechanism, causing the front and rear connecting rods to gradually straighten, generating a force amplification effect. This pushes the moving mold plate along the guide pillars and linear guide rails towards the fixed mold plate, ultimately achieving mold closing and reaching the predetermined clamping force.

[0032] After the mold is closed, the device remains in the locked state, and the injection system performs the injection and pressure holding process. The self-locking characteristics of the roller screw mechanism and the force locking effect of the inclined five-point double elbow mechanism work together to ensure that the mold always remains tightly closed under injection pressure, preventing flash from forming on the product.

[0033] After the pressure holding period ends, the servo motor rotates in the opposite direction, driving the crosshead to move backward through the roller screw mechanism. The inclined five-point double-curved elbow mechanism retracts accordingly, pulling the moving platen and the fixed platen apart to complete the mold opening action. The slider and linear guide rail ensure a smooth and stable mold opening process. After the mold is in place, the ejection system works to eject the molded product from the mold, completing the entire injection molding cycle.

[0034] Although embodiments of the present invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the present invention, the scope of which is defined by the appended claims and their equivalents.

Claims

1. An all-electric injection molding machine clamp apparatus, characterized by, The system includes a tail plate (16), a moving template (3), a fixed template (1), and several guide posts (2) connecting the moving template (3) and the fixed template (1). Each of the guide posts (2) has a threaded post at its tail end, and the threaded posts are threaded through the tail plate (16). The system also includes: The ball screw mechanism (5) includes a screw, a support base (51), a cage (52), a crosshead (53), a bearing (55), and several rollers (54). The screw horizontally passes through the tail plate (16) and is rotatably mounted inside the tail plate (16) via the support base (51). The screw is connected to the support base (51) via the bearing (55). Several rollers (54) are provided, and both ends are fixed in position via the cage (52). Nuts are sleeved on the outside of the rollers (54). The rollers (54) and the nuts are threadedly engaged. The rollers (54) are threadedly engaged with the screw. The crosshead (53) is fixedly connected to the outside of the nut. A five-point double-curved elbow mechanism (4) is used to connect the tail plate (16), the moving template (3) and the crosshead (53); The drive assembly (6) is used to drive the lead screw to rotate.

2. An all-electric injection molding machine clamping apparatus as claimed in claim 1, wherein, The rollers (54) are provided in eight units.

3. A fully electric injection molding machine clamping apparatus as claimed in claim 1, wherein, The roller (54) is provided with spur gears at both ends, and the nut is provided with gear rings that cooperate with the spur gears at both ends.

4. A fully electric injection molding machine clamping apparatus as claimed in claim 1, wherein, The ball screw mechanism (5) also includes the bearing (55), end cap (56) and locking nut (57). The bearing (55) is placed between the screw and the support seat (51) and is securely connected by the end cap (56) and locking nut (57).

5. A fully electric injection molding machine clamping apparatus as claimed in claim 1 wherein, The oblique five-point double elbow mechanism (4) includes four front connecting rods (41), four rear connecting rods (43) and two first connecting rods (44) arranged symmetrically in the upper and lower parts. The front connecting rods (41) and the rear connecting rods (43), the front connecting rods (41) and the moving template (3), the rear connecting rods (43) and the tail plate (16), the rear connecting rods (43) and the first connecting rods (44), and the first connecting rods (44) and the crosshead (53) are all hinged by pins (42).

6. The mold clamping device for an all-electric injection molding machine as described in claim 1, characterized in that, The drive assembly (6) includes a servo motor (61), a first mold-locking pulley (62), and a second mold-locking pulley (63). The servo motor (61) is fixedly mounted on the tail plate (16) via a mold-locking motor plate (64). The output shaft of the servo motor (61) is fixedly connected to the first mold-locking pulley (62), and the lead screw is fixedly connected to the second mold-locking pulley (63). The first mold-locking pulley (62) and the second mold-locking pulley (63) are connected by a synchronous belt (15).

7. A fully electric injection molding machine clamping apparatus as claimed in claim 1 wherein, The bottom of the moving template (3) is fixedly installed with an adjustment block (7), and a pair of sliders (8) are fixedly connected to the bottom of the adjustment block (7). A linear guide rail (9) is provided on the base of the injection molding machine, and the pair of sliders (8) are slidably disposed in the linear guide rail (9).

8. The mold clamping device for an all-electric injection molding machine as described in claim 1, characterized in that, A number of the guide posts (2) are fixedly connected to threaded posts threaded through the tail plate (16) at the ends away from the fixed template (1). A first mold adjustment gear ring (10) is provided at the center of the tail plate (16). The first mold adjustment gear ring (10) is rotatably mounted on the tail plate (16). A second mold adjustment gear (12) is threaded on each of the threaded posts. The second mold adjustment gear (12) meshes with the first mold adjustment gear ring (10). A first mold adjustment gear (11) meshes with one side of the second mold adjustment gear (12) through an idler gear (13). The first mold adjustment gear (11) is connected to a mold adjustment motor (14).

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