A mold opening and closing mechanism and injection molding machine

Abstract

This invention discloses a mold opening and closing mechanism and an injection molding machine, including a mold and an opening and closing mechanism. The opening and closing mechanism includes: a hydraulic cylinder connected to the mold for driving the mold to open and close; a lead screw threadedly connected to the piston rod of the hydraulic cylinder; and a drive motor for driving the lead screw. During operation, on the one hand, the drive motor drives the lead screw, which in turn drives the piston rod, providing some power; on the other hand, the hydraulic cylinder itself also carries some driving force. Therefore, it can improve the driving force of a single hydraulic cylinder while the structure of the drive motor and lead screw does not pollute the working environment, and it is simpler than power amplification structures and dual oil pump structures.

Description

Technical Field

[0001] This invention belongs to the field of mold technology, and specifically relates to a mold opening and closing mechanism with hybrid oil and electricity drive. Background Technology

[0002] Molds, often called the "mother of manufacturing," are crucial tools in the industry. During use, molds often require movement, such as the opening and closing of molds in injection molding machines, typically accomplished using hydraulic systems. While hydraulic systems offer high output force, they also have significant drawbacks, such as the need to address insufficient hydraulic pressure and oil leaks leading to inadequate cleanliness in the production environment. To address insufficient hydraulic pressure, hydraulic systems rely on timely oil replenishment by oil pumps. Existing technology, such as a Chinese patent document (CN106194867A) disclosing a "hydraulic system and mold," incorporates both a first and a second oil pump, which can operate simultaneously. This provides sufficient pressurized oil to both the first and second cylinder groups, improving the reliability of the hydraulic system. However, this approach increases structural complexity and does not resolve the issue of insufficient cleanliness in the production environment.

[0003] In another existing technology, such as Figure 1 As shown, hydraulic power is amplified by setting a power amplification structure to reduce the need for oil replenishment. The power amplification structure 4 generally uses devices such as connecting rods, which require lubrication. Therefore, it is easy for oil stains to adhere to the mold, making it unsuitable for the production conditions of some products with high hygiene requirements, such as the production of medical devices. Summary of the Invention

[0004] In order to overcome the problems of insufficient cleanliness and complex structure of existing mold opening and closing mechanisms, this invention provides a mold opening and closing mechanism, i.e., an injection molding machine, driven by a hybrid hydraulic cylinder and motor, which does not pollute the working environment and eliminates the need for a complex structure.

[0005] This invention is achieved through the following technical solution: a mold opening and closing mechanism, comprising a mold and an opening and closing mechanism, wherein the opening and closing mechanism includes:

[0006] A hydraulic cylinder, which is connected to the mold, is used to drive the mold to open and close;

[0007] A lead screw, which is threadedly connected to the piston rod of a hydraulic cylinder;

[0008] The drive motor is used to drive the lead screw.

[0009] During operation, the drive motor drives the lead screw, which in turn drives the piston rod to provide some power. On the other hand, the hydraulic cylinder itself also has some driving force. Therefore, it can improve the driving force of a single hydraulic cylinder. The structure of the drive motor and lead screw does not pollute the working environment, and it is simpler than the power amplification structure and the dual oil pump structure.

[0010] Preferably, the piston inside the hydraulic cylinder is provided with an oil replenishment channel, which connects both sides of the piston. An oil replenishment valve is installed within the oil replenishment channel to open and close it. During use, oil from the side with smaller internal space within the hydraulic cylinder can be replenished to the side with larger internal space through the oil replenishment channel, eliminating the need for an oil pump and significantly improving replenishment efficiency. Furthermore, in some applications where driving force requirements are not high, the oil pump can even be omitted, eliminating the need for external oil replenishment, simplifying the structure, and further improving equipment cleanliness.

[0011] Preferably, the hydraulic cylinder has an opening / closing rod on the side opposite to the piston rod. The mold includes an upper mold near the hydraulic cylinder and a lower mold away from the hydraulic cylinder. The opening / closing rod passes through the upper mold and connects to the lower mold, and the opening / closing rod is slidably connected to the upper mold. Since the piston rod needs to be connected to the lead screw, an opening / closing rod also needs to be provided on the other side of the piston to connect the upper and lower molds. Therefore, the hydraulic cylinder is a double-rod type.

[0012] Preferably, the hydraulic cylinder is divided into two chambers by a piston, and each chamber is provided with an inlet and outlet for connection to an oil pump. To increase the power provided by the hydraulic cylinder, both chambers are connected to the oil pump, further improving the oil replenishment efficiency and resulting in a greater driving force for the opening and closing mechanism.

[0013] Preferably, the oil replenishment channel includes an oil outlet channel communicating with a cavity on one side of the piston rod, an oil inlet channel communicating with a cavity on one side of the opening / closing rod, and a valve channel connecting the oil outlet channel and the oil inlet channel and accommodating the oil replenishment valve. The valve channel has a sliding cavity on the side facing the oil inlet channel for accommodating the oil replenishment valve to open the valve channel. When oil replenishment is needed on one side, the sliding oil replenishment valve connects the oil inlet channel and the oil outlet channel to complete the oil replenishment.

[0014] Preferably, the replenishing valve is dumbbell-shaped, with both ends capable of sealing the replenishing valve channel, and the length of the replenishing valve is greater than the distance between the inlet and outlet channels where they connect to the replenishing valve channel. The dumbbell-shaped design of the replenishing valve allows the outer circumference of the valve to form an oil passage within the replenishing valve channel with the inner wall of the replenishing valve channel, resulting in more uniform oil flow and lower resistance within the replenishing valve channel.

[0015] Preferably, one end of the replenishing valve is provided with a protection section with a cross-sectional area larger than that of both ends of the replenishing valve, and the replenishing valve channel is correspondingly provided with a protection channel for the protection section to slide, so as to prevent the replenishing valve from hitting the piston when sliding and avoiding damage.

[0016] Preferably, the opening and closing rod has a cavity, and the oil replenishing valve has a connecting rod for operating the oil replenishing valve on the side facing the opening and closing rod. The connecting rod passes through the cavity of the opening and closing rod, which facilitates manual or automatic control of the opening and closing of the oil replenishing valve from the side of the opening and closing rod.

[0017] An injection molding machine includes the aforementioned mold opening and closing mechanism, and also includes injection molding equipment. The simplified structure of the injection molding machine makes the placement of the injection molding equipment more convenient.

[0018] Compared with the prior art, the advantages of the present invention are:

[0019] The motor provides driving force through the lead screw and hydraulic pump, which increases the total driving force of the opening and closing mold. At the same time, the structure of the drive motor and lead screw does not pollute the working environment, and it is simpler than the power amplification structure and the dual oil pump structure. Attached Figure Description

[0020] Figure 1 A three-dimensional schematic diagram of an existing mold opening and closing mechanism with a power-driven amplification structure and an injection molding machine;

[0021] Figure 2 This is a side view of the injection molding machine.

[0022] Figure 3 Example 1 Figure 2 A schematic diagram of the cross-section cut at point AA;

[0023] Figure 4 for Figure 3 Enlarged view of point B in the middle;

[0024] Figure 5 Example 2 Figure 2 Enlarged diagram of point AA;

[0025] Figure 6 This is a three-dimensional schematic diagram of the appearance of an injection molding machine.

[0026] In the diagram: 1. Hydraulic cylinder; 11. Piston rod; 12. Oil replenishment channel; 121. Oil outlet channel; 122. Oil inlet channel; 123. Valve channel; 124. Sliding chamber; 13. Oil replenishment valve; 131. Protection section; 14. Oil inlet and outlet port; 15. Opening and closing rod; 16. Connecting rod; 2. Lead screw; 3. Drive motor; 4. Power amplification structure; 5. Injection molding equipment. Detailed Implementation

[0027] To make the technical means, creative features, objectives and effects of this invention easier to understand, the following description, in conjunction with the accompanying drawings and specific embodiments, further explains how this invention is implemented.

[0028] Example 1, as Figure 2-4As shown, a mold opening and closing mechanism includes a mold and an opening and closing mechanism. The mold includes an upper mold near the hydraulic cylinder 1 and a lower mold away from the hydraulic cylinder 1. The opening and closing mechanism includes:

[0029] Hydraulic cylinder 1 is connected to the mold and is used to drive the mold to open and close.

[0030] Lead screw 2 is threadedly connected to piston rod 11 of hydraulic cylinder 1;

[0031] Drive motor 3 is used to drive lead screw 2.

[0032] The hydraulic cylinder 1 includes:

[0033] The oil replenishment channel 12 connects the two sides of the piston of the hydraulic cylinder 1 and is equipped with an oil replenishment valve 13 for opening and closing the oil replenishment channel 12.

[0034] Oil inlet and outlet ports 14 are located at both ends of hydraulic cylinder 1 and are used to connect with oil pump to increase the power provided by hydraulic cylinder 1, further improve oil replenishment efficiency, and make the driving force of opening and closing mechanism greater.

[0035] The opening and closing rod 15 is located on the side of the hydraulic cylinder 1 facing away from the piston rod 11. The opening and closing rod 15 passes through the upper mold and connects to the lower mold. The opening and closing rod 15 is slidably connected to the upper mold. A cavity is provided inside the opening and closing rod 15. A connecting rod 16 for operating the oil replenishing valve 13 is provided on the side of the oil replenishing valve 13 facing the opening and closing rod 15. The connecting rod 16 passes through the cavity of the opening and closing rod 15, which facilitates manual or automatic control of the opening and closing of the oil replenishing valve 13 from the side of the opening and closing rod 15.

[0036] The working principle of this embodiment is that the drive motor drives the lead screw 2, and the lead screw 2 drives the piston rod 11 to provide a part of the power. The hydraulic cylinder 1 itself also has a part of the driving force. Furthermore, when the oil on the side with smaller internal space of the hydraulic cylinder 1 can be replenished to the side with larger internal space of the hydraulic cylinder 1 through the oil replenishment channel 12, the oil replenishment does not need to go through the oil pump, which greatly improves the oil replenishment efficiency. Therefore, it can improve the driving force of a single hydraulic cylinder 1, and the structure of the drive motor and lead screw 2 does not pollute the working environment. Moreover, it is simpler than the power amplification structure and the dual oil pump structure.

[0037] Furthermore, in some scenarios where the driving force requirement is not high, the oil pump can be omitted, eliminating the need for external oil replenishment, resulting in a simpler structure and further improving the cleanliness of the equipment.

[0038] Example 2, as Figure 5 As shown, the oil replenishment channel 12 includes:

[0039] The oil outlet channel 121 is connected to the cavity on one side of the piston rod 11;

[0040] The oil inlet channel 122 is connected to the cavity on one side of the opening / closing lever 15;

[0041] Valve passage 123 connects oil outlet passage 121 and oil inlet passage 122 and accommodates oil replenishment valve 13.

[0042] Furthermore, the valve passage 123 has a sliding cavity 124 on the side facing the oil inlet passage 122 to accommodate the replenishing valve 13 and open the valve passage 123. The replenishing valve 13 is dumbbell-shaped, with both ends capable of sealing the replenishing valve 13 passage, and the length of the replenishing valve 13 is greater than the distance between the oil inlet passage 122 and the oil outlet passage 121 where the replenishing valve 13 passage connects. The dumbbell-shaped replenishing valve 13 creates an oil passage within the replenishing valve 13 passage by its outer periphery and the inner wall of the replenishing valve 13 passage, resulting in more uniform oil flow and less resistance within the valve passage 123.

[0043] In addition, one end of the replenishing valve 13 is provided with a protection section 131 with a cross-sectional area larger than that of both ends of the replenishing valve 13, and the valve passage 123 is correspondingly provided with a protection channel for the protection section 131 to slide, so as to prevent the replenishing valve 13 from hitting the piston when sliding and avoiding damage.

[0044] The other structures are the same as in Embodiment 1.

[0045] Example 3: An injection molding machine, such as Figure 2 , Figure 3 and Figure 6 As shown, this includes the mold opening and closing mechanism and injection molding equipment 5 of Embodiment 2, in comparison. Figure 1 It is easy to see that the simplification of the mold opening and closing equipment makes the overall structure of the injection molding machine simpler.

Claims

1. A mold opening and closing mechanism, comprising a mold and an opening and closing mechanism, characterized in that, The opening and closing mechanism includes: A hydraulic cylinder is connected to the mold and is used to drive the mold to open and close. The inlet and outlet ports are located at both ends of the hydraulic cylinder and are used to connect to the oil pump. Both chambers are connected to the oil pump to increase the power provided by the hydraulic cylinder. Lead screw, which is threadedly connected to the piston rod of the hydraulic cylinder; Drive motor, used to drive the lead screw; The opening and closing mechanism is driven by a drive motor that drives a lead screw, which, together with an oil pump, provides the driving force. The piston inside the hydraulic cylinder is equipped with an oil replenishment channel, which connects both sides of the piston. An oil replenishment valve is installed in the oil replenishment channel to open and close the oil replenishment channel. The oil replenishment channel includes an oil outlet channel communicating with a cavity on one side of the piston rod, an oil inlet channel communicating with a cavity on one side of the opening / closing rod, and a valve channel communicating with the oil outlet channel and the oil inlet channel and accommodating the oil replenishment valve. The valve channel is provided with a sliding cavity on the side facing the oil inlet channel for accommodating the oil replenishment valve to open the valve channel.

2. The mold opening and closing mechanism according to claim 1, characterized in that: The hydraulic cylinder has an opening and closing rod on the side opposite to the piston rod.

3. The mold opening and closing mechanism according to claim 2, characterized in that: The mold includes an upper mold near the hydraulic cylinder and a lower mold away from the hydraulic cylinder. The opening and closing rod passes through the upper mold and connects to the lower mold. The opening and closing rod is slidably connected to the upper mold.

4. The mold opening and closing mechanism according to claim 2 or 3, characterized in that: The opening and closing rod has a cavity inside.

5. The mold opening and closing mechanism according to claim 4, characterized in that: The oil replenishing valve is provided with a connecting rod for operating the oil replenishing valve on the side facing the opening and closing rod, and the connecting rod extends out of the cavity of the opening and closing rod.

6. The mold opening and closing mechanism according to claim 1, 2, or 3, characterized in that: The replenishing valve is dumbbell-shaped, with both ends capable of sealing the replenishing valve channel, and the length of the replenishing valve is greater than the distance between the oil inlet channel and the oil outlet channel at the replenishing valve channel.

7. The mold opening and closing mechanism according to claim 6, characterized in that: One end of the replenishing valve is provided with a protection section whose cross-sectional area is larger than that of both ends of the replenishing valve, and the replenishing valve channel is correspondingly provided with a protection channel that allows the protection section to slide.

8. An injection molding machine comprising the mold opening and closing mechanism according to any one of claims 1-7, characterized in that: It also includes injection molding equipment.

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