A compression molding device for servo cylinder mold

Abstract

The application discloses a kind of servo cylinder die closing's compression molding device, it is related to mould equipment field, comprising: upper die;Lower die, the upper die is located above the lower die;And servo cylinder die closing mechanism, the servo cylinder die closing mechanism can drive the lower die reciprocating linear motion up and down;Wherein, the servo cylinder die closing mechanism includes driving mechanism, guide mechanism and nut rotating ball screw, the nut rotating ball screw includes screw;When driving mechanism drives nut rotating ball screw to move, the screw reciprocating linear motion up and down and penetrates the guide mechanism;The screw is connected with the lower die;Wherein, the engagement section of the screw surface pitch gradually decreases from top to bottom.This servo cylinder die closing's compression molding device replaces hydraulic die closing device, solves the problem of oil leakage and oil pollution in hydraulic die closing device.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of mold equipment, in particular to a servo cylinder combined mold compression molding device. BACKGROUND

[0002] With the development of economy, domestic large beverage enterprises have strong demand for high-speed, high-efficiency and high-stability molding production equipment production lines, and the development of existing injection molding process is increasingly mature. However, for thin-walled multi-cavity products, the traditional injection molding process has little advantage, and the initial development of the mold for thin-walled multi-cavity products requires a large investment and a long cycle. The use of rotary compression molding process can simplify the mold, so that the mold can focus on the design and processing of a single structure, and through the rotating cycle, multiple single-structure molds are arranged in a circle. Compared with the injection molding process for thin-walled multi-cavity products, the cycle is also more advantageous. For the compression molding process of multi-cavity, since the mold is arranged on the circumference of the turntable, and the single mold needs to be opened and closed, the specific process is as follows: the turntable rotates with the multiple molds, at a specific position, the mold is opened in turn, at this time, other devices unload the molded products and load the molten plastic particles into the mold. When the above two works are completed, the turntable rotates while the mold needs to be quickly closed. After quick closing, the upper and lower molds need to provide a large relative pressure to promote the rapid molding of the molded product in the mold and at the same time to rapidly cool. When this process is involved, to ensure the efficiency of production, first, the maximum number of molds needs to be arranged on the turntable with the same circumferential diameter; second, the maximum limit of each process cycle needs to be optimized to improve production efficiency. Specifically, in the process of mold opening and closing, when the mold is quickly closed, the load of the actuator connected to the mold is small when it rises or falls, but to improve efficiency, it needs to quickly complete this long stroke. When the mold is close to the completion of the closing, due to the existence of internal glue, the load resistance rises, and the actuator needs to provide a large closing force to continuously provide a large pressure to the internal glue at a slow speed, so that the internal glue is molded and cooled at the same time. Under this working condition, the traditional hydraulic cylinder is suitable for this working condition by quickly closing with low pressure and large flow, and by assisting with large pressure and small flow when closing. Therefore, existing manufacturers use hydraulic closing devices and structures.

[0003] The existing hydraulic mold closing device switches the corresponding pressure and flow at different times to match the working conditions of closing the mold with small load quickly and locking the mold with large pressure. However, the existing hydraulic mold closing device also has the following problems: first, the impact on the mold is large when closing the mold quickly, the processing and maintenance requirements of the mold are high, and the service life of the mold is relatively short. Especially on the machine with high-speed rotation and more cavities, due to the quick opening and closing of the mold and the sharing of the flow control valve by multiple opening and closing cylinders, considering the impact caused by the hydraulic pressure fluctuation, these all greatly increase the control difficulty of the quick closing of the cylinder, causing the impact on the mold and reducing the service life of the mold. Second, the quality and cleanliness of the hydraulic oil are very important for the quick closing control of the hydraulic cylinder. If the hydraulic oil is contaminated or the performance of the hydraulic oil is degraded, the control difficulty of the quick closing of the hydraulic cylinder will be increased and the damage of the related parts of the hydraulic system will be accelerated. Third, a single hydraulic cylinder actuator is matched with a single mold. The hydraulic cylinder actuator needs to be operated for a long time for quick closing and high-pressure closing. This requires higher requirements for the guide of the hydraulic cylinder piston, the wear resistance of the piston rod, and especially the impact on the cylinder cover when the quick closing is not controlled well. These all greatly increase the possibility of oil leakage of the corresponding sealing elements and the possibility of oil pollution. SUMMARY

[0004] In order to overcome the deficiencies of the prior art, the purpose of the present application is to provide a servo electric cylinder mold closing plastic molding device which replaces the hydraulic mold closing device and solves the problems of oil leakage and oil pollution of the hydraulic system in the hydraulic mold closing device.

[0005] The present application adopts the following technical solutions:

[0006] A servo electric cylinder mold closing plastic molding device, comprising: an upper mold; a lower mold, the upper mold being located above the lower mold; and a servo electric cylinder mold closing mechanism capable of driving the lower mold to move up and down in a straight line; wherein the servo electric cylinder mold closing mechanism comprises a driving mechanism, a guide mechanism and a nut rotating ball screw, the nut rotating ball screw comprising a screw rod; when the driving mechanism drives the nut rotating ball screw to move, the screw rod moves up and down in a straight line through the guide mechanism; the screw rod is connected with the lower mold; wherein the lead of the meshing section on the surface of the screw rod gradually decreases from top to bottom.

[0007] As a preferred, the driving mechanism comprises a servo motor, a connecting shaft and a speed reducer, and the nut rotating ball screw, the connecting shaft, the speed reducer and the servo motor are connected in sequence.

[0008] As preferred, the rotating nut type ball screw is arranged on the lower turntable.

[0009] As preferred, the rotating nut type ball screw is arranged on the lower turntable.

[0010] As preferred, the upper mold is arranged in an array around the center line of the upper turntable, and the lower mold is arranged in an array around the center line of the lower turntable.

[0011] As preferred, the servo cylinder mold closing mechanism is arranged in a plurality of sets, and each servo cylinder mold closing mechanism corresponds to a lower mold.

[0012] As preferred, the guide mechanism is arranged in a plurality of sets, and each guide mechanism corresponds to a servo cylinder mold closing mechanism.

[0013] As preferred, the lower turntable is provided with a plurality of accommodating holes, and the accommodating holes are arranged through the lower turntable, and the guide mechanism is partially embedded in the upper end of the accommodating hole.

[0014] As preferred, the lower end of the accommodating hole is provided with a motor mounting seat, the motor mounting seat is partially embedded in the accommodating hole, and the driving mechanism is connected with the motor mounting seat.

[0015] As preferred, the servo cylinder mold closing mechanism is provided with an encoder.

[0016] Compared with the prior art, the beneficial effects of the present application are that the servo cylinder mold closing plastic molding device of the present application replaces the hydraulic mold closing device, compared with the hydraulic scheme, the whole machine structure is simplified, the problems of oil leakage and oil pollution in the hydraulic system of the hydraulic mold closing device are solved, and the energy saving effect of the machine is effectively improved. The driving structure can drive the rotating nut type ball screw to operate, so that the screw rod realizes linear movement up and down, realizes the opening and closing of the upper mold and the lower mold, and through the arrangement of the guide mechanism, sufficient side tilt torque is provided, which provides effective guidance for rapid mold closing and high pressure mold closing. The screw rod is a variable lead screw rod, and the lead of the meshing section on the surface of the screw rod gradually decreases from top to bottom. When rapid mold closing is performed, the lead is larger, and the closer to the mold closing, the smaller the lead. Through the gradual change of the lead, the working conditions of rapid mold closing and high pressure mold closing can be more suitable, and the precision control of rapid mold closing and high pressure mold closing is greatly increased, the mold life is effectively increased, and the product quality is improved. BRIEF DESCRIPTION OF DRAWINGS

[0017] Fig. 1 FIG. 1 is a structural schematic diagram of a servo cylinder mold closing plastic molding device in an embodiment of the present application.

[0018] Fig. 2 FIG. 2 is a structural schematic diagram of a servo cylinder mold closing mechanism in an embodiment of the present application.

[0019] Figure numerals: 1. Upper mold; 2. Lower mold; 3. Servo electric cylinder mold clamping mechanism; 4. Driving mechanism; 5. Guide mechanism; 6. Nut-rotating ball screw; 7. Screw; 8. Servo motor; 9. Connecting shaft; 10. Reducer; 11. Turntable mechanism; 12. Upper turntable; 13. Lower turntable; 14. Receiving hole; 15. Motor mounting seat; 16. Plastic particles. DETAILED DESCRIPTION

[0020] The following combination Figs. 1-2 The technical solution provided by the invention is explained in more detail.

[0021] like Figs. 1-2 As shown, an embodiment of the present invention provides a compression molding device with a servo electric cylinder mold clamping, comprising: an upper mold 1; a lower mold 2, the upper mold 1 is located above the lower mold 2; and a servo electric cylinder mold clamping mechanism 3, the servo electric cylinder mold clamping mechanism 3 can drive the lower mold 2 to move up and down reciprocatingly; wherein, the servo electric cylinder mold clamping mechanism 3 includes a driving mechanism 4, a guide mechanism 5 and a nut rotating ball screw 6, and the nut rotating ball screw 6 includes a screw 7; when the driving mechanism 4 drives the nut rotating ball screw 6 to move, the screw 7 penetrates the guide mechanism 5 and moves up and down reciprocatingly; the screw 7 is connected to the lower mold 2; wherein, the lead of the meshing section on the surface of the screw 7 gradually decreases from top to bottom.

[0022] The drive mechanism 4 includes a servo motor 8, a connecting shaft 9, and a reducer 10. The nut-rotating ball screw 6, the connecting shaft 9, the reducer 10, and the servo motor 8 are connected in sequence. The servo motor 8 drives the reducer 10, which in turn drives the nut-rotating ball screw 6, enabling the screw 7 to achieve reciprocating linear motion up and down. Depending on the mold closing conditions, long-stroke mold closing requires fast speed and light load, requiring a small reduction ratio for the reducer 10 and a correspondingly high rated speed and dynamic performance for the servo motor 8. Short-stroke, high-pressure mold closing requires a large reduction ratio for the reducer 10 and a high rated output torque for the motor. The screw 7 and nut in the nut-rotating ball screw 6 are designed as variable-lead screws 7 and nut. This means that the lead is larger during fast mold closing and decreases as the mold approaches the closing position. By gradually varying the lead and combining it with a suitable servo motor 8 and reduction ratio, the motor power and size are effectively reduced while perfectly adapting to both fast and high-pressure mold closing conditions.

[0023] The compression molding device of the servo cylinder mold closing mechanism of the embodiment further comprises a rotating disc mechanism 11, the rotating disc mechanism 11 comprises an upper rotating disc 12 and a lower rotating disc 13, the upper mold 1 and the lower mold 2 are both provided with a plurality of upper molds 1 and lower molds 2, the upper mold 1 is arranged on the upper rotating disc 12, and the lower mold 2 is arranged on the lower rotating disc 13. The nut rotating type ball screw 6 is arranged on the lower rotating disc 13. The upper molds 1 are arranged in an array around the center line of the upper rotating disc 12, and the lower molds 2 are arranged in an array around the center line of the lower rotating disc 13. The lower mold 2 corresponding to each upper mold 1 is arranged in alignment with the same center line. The servo cylinder mold closing mechanism 3 is provided with a plurality of servo cylinder mold closing mechanisms 3, and the servo cylinder mold closing mechanism 3 corresponds to the lower mold 2. The servo cylinder mold closing mechanism 3 is used to drive the lower mold 2 to open and close the upper mold. The guide mechanism 5 is provided with a plurality of guide mechanisms 5, and the guide mechanism 5 corresponds to the servo cylinder mold closing mechanism 3. The guide mechanism 5 is used to provide sufficient roll moment for the servo cylinder mold closing mechanism 3 and provide effective guidance for rapid mold closing and high-pressure mold closing.

[0024] A plurality of groups of molds of single structure are arranged uniformly on the circumference of the rotating disc, and an equal number of servo cylinder mold closing mechanisms 3 are arranged in central alignment. Through continuous rotation of the rotating disc, when the rotating disc rotates to a specific position, the upper mold 1 and the lower mold 2 are opened, and the two are at the farthest position. At this time, the molded products unloaded and the molten plastic particles 16 loaded are simultaneously performed. After the above-mentioned operation is completed, the mold is quickly closed, that is, the lower mold 2 rises at a faster speed, and when it approaches the upper mold 1, a higher pressure needs to be provided to compress and mold the molten plastic particles 16 in the closed cavity of the mold, and the high-pressure state is maintained for a period of time, so that the molded molded products are cooled and stabilized. When the rotating disc rotates to a specific position again, the mold is opened again, and the cycle is repeated, so that qualified and stable molded products can be continuously obtained, and the production process cycle is effectively shortened.

[0025] The lower rotating disc 13 is provided with a plurality of accommodating holes 14, the accommodating holes 14 are arranged through the lower rotating disc 13, the guide mechanism 5 is partially embedded in the upper end of the accommodating hole 14, and the part of the guide mechanism 5 not embedded in the accommodating hole 14 is fixedly connected with the lower rotating disc 13 by screws. On the one hand, the installation structure of the guide mechanism 5 is more stable, and on the other hand, the device structure is more compact, and the occupied space is reduced.

[0026] The lower end of the accommodating hole 14 is provided with a motor mounting seat 15, the motor mounting seat 15 is partially embedded in the accommodating hole 14, the part of the motor not embedded in the accommodating hole is fixedly connected with the lower rotating disc 13 by screws, the driving mechanism 4 is connected with the motor mounting seat 15, specifically, the speed reducer 10 is connected with the motor mounting seat 15, and the servo motor 8 is mounted on the motor mounting seat 15 through the speed reducer 10. On the one hand, the installation structure of the motor mounting seat 15 is more stable, and on the other hand, the device structure is more compact, and the occupied space is reduced.

[0027] The servo cylinder clamping mechanism 3 is provided with an encoder. The encoder can detect the position of the servo cylinder clamping mechanism 3 in real time, so that the parameters of the feeding, such as injection or overfeeding, can be quickly detected. The servo cylinder clamping mechanism 3 compares the position and output torque with standard data, so that errors can be quickly detected, precise supervision and prediction warning functions are realized. Through effective program control, intelligent supervision and management of the machine can be realized.

[0028] The molten plastic particles 16 are placed in the cavity of the lower mold 2. The servo cylinder clamping mechanism 3 controls the up-and-down reciprocating linear motion of the lower mold 2, so that the lower mold 2 completes the rapid clamping, high-pressure clamping and opening actions relative to the upper mold 1, so that the molten plastic particles 16 are rapidly formed and cooled in the mold through the pressure action, thereby obtaining qualified and stable molded products.

[0029] The above-mentioned embodiments are only preferred embodiments of the present application, and cannot be used to limit the scope of protection of the present application. Any non-essential changes and replacements made by those skilled in the art on the basis of the present application shall fall within the scope of protection of the present application.

Claims

1. A servo electric cylinder mold clamping compression molding device, characterized in that: include: Upper mold; A lower mold, the upper mold is located above the lower mold; and a servo electric cylinder mold clamping mechanism, the servo electric cylinder mold clamping mechanism can drive the lower mold to move up and down in a reciprocating linear motion; The servo electric cylinder mold clamping mechanism includes a driving mechanism, a guide mechanism, and a nut-rotating ball screw, wherein the nut-rotating ball screw includes a screw rod; when the driving mechanism drives the nut-rotating ball screw to move, the screw rod penetrates the guide mechanism and moves back and forth linearly; the screw rod is connected to the lower mold; The lead of the meshing section on the surface of the screw gradually decreases from top to bottom; It also includes a turntable mechanism, the turntable mechanism includes an upper turntable and a lower turntable, and a plurality of upper molds and lower molds are provided, the upper molds correspond to the lower molds one by one, the upper molds are provided on the upper turntable, and the lower molds are provided on the lower turntable; the nut rotating ball screw is provided on the lower turntable; There are several servo electric cylinder mold clamping mechanisms, which correspond to the lower mold one by one. There are several guide mechanisms, which correspond to the servo electric cylinder mold clamping mechanisms one by one. There are several accommodating holes on the lower turntable, which pass through the lower turntable, and the guide mechanism is partially embedded in the upper end of the accommodating hole.

2. The servo electric cylinder mold clamping compression molding device according to claim 1, characterized in that: The driving mechanism includes a servo motor, a connecting shaft and a reducer, and the nut-rotating ball screw, the connecting shaft, the reducer and the servo motor are connected in sequence.

3. The servo electric cylinder mold clamping compression molding device according to claim 1, characterized in that: The upper molds are arranged in an array around the center line of the upper turntable, and the lower molds are arranged in an array around the center line of the lower turntable.

4. The servo electric cylinder mold clamping compression molding device according to claim 1, characterized in that: A motor mounting seat is provided at the lower end of the accommodating hole. The motor mounting seat is partially embedded in the accommodating hole. The driving mechanism is connected to the motor mounting seat.

5. The servo electric cylinder mold clamping compression molding device according to claim 1, characterized in that: The servo electric cylinder mold clamping mechanism is provided with an encoder.

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