A flexible assembly injection molding machine rapid injection structure

Abstract

This utility model discloses a flexible assembly rapid injection structure for an injection molding machine, including a front cover, a rear cover, a cylinder barrel, a differential rod, a piston rod, and a piston. The front and rear covers respectively seal both ends of the cylinder barrel, forming a closed cylinder cavity inside. The differential rod is a hollow tube, with one end fixedly connected to the rear cover and communicating with the oil port located on the rear cover, and the other end extending to the front cover. The rear end of the piston rod has a blind groove, which houses the differential rod. The hollow inner cavity of the differential rod and the blind groove of the piston rod are interconnected through the suspended end of the differential rod to form a differential cavity. The front end of the piston rod extends outside the front cover. The piston is threaded onto the rear end of the piston rod, and the piston is tightly fitted against the inner wall of the cylinder cavity, thus sealingly dividing the cylinder cavity into a front cavity and a rear cavity. The oil port located on the front cover communicates with the front cavity. This utility model achieves assembly through threaded matching, making the structure easier to assemble, wider in application, and better enabling miniaturized production.

Description

Technical Field

[0001] This utility model relates to the field of injection molding machine technology, specifically to a flexible assembly rapid injection structure for injection molding machines. Background Technology

[0002] Injection molding machines, also known as injection molding machines or injection molding machines, are the main molding equipment used to produce various shapes of plastic products from thermoplastic or thermosetting plastics using plastic molds. In one cycle of an injection molding machine, a certain amount of plastic is heated and plasticized within a specified time, and then, under certain pressure and speed, the molten plastic is injected into the mold cavity through a screw.

[0003] Currently, differential hydraulic cylinder structures are mainly used in injection molding machines on the market. Their function is to ensure accurate and stable input of the rubber material into the mold. The differential injection hydraulic cylinder structure mainly includes a front cover with a front port, a rear cover with a rear port, a cylinder barrel located between the front and rear covers, a piston rod, and a piston installed in the middle of the piston rod via a piston nut. The front cover, rear cover, and cylinder barrel together constitute the cylinder body, and the cylinder body has a cylindrical cavity inside. The two ends of the piston rod extend out of the front and rear covers respectively, and the middle of the piston rod is located in the cylindrical cavity. The piston is also located in the cylindrical cavity, dividing the cylindrical cavity into a front cylindrical cavity and a rear cylindrical cavity. The front port is connected to the front cylindrical cavity, and the rear port is connected to the rear cylindrical cavity. During differential injection, the injection area S1 in the front cylindrical cavity is larger than the injection area S2 in the rear cylindrical cavity. Under the action of differential force, the injection piston synchronously drives the piston rod to move towards the rear cylindrical cavity.

[0004] However, the hydraulic cylinder mechanism of injection molding machines currently generally relies on screw assembly, which is not suitable for miniaturization and cannot be matched with small injection molding machines. Utility Model Content

[0005] To address the technical problems existing in the prior art, the purpose of this utility model is to provide a flexible assembly rapid injection structure for injection molding machines.

[0006] The objective of this utility model is achieved through the following technical solution: a flexible assembly rapid injection structure for injection molding machines.

[0007] Furthermore, the piston includes a ring-shaped body and an end cap; the inner surface of the body is a stepped hole, and the small-sized stepped surface of the body is threadedly fitted to the rear end of the piston rod; the large-sized stepped surface of the body houses the end cap, the inner surface of the end cap is a stepped hole, and the large-sized stepped surface of the end cap is threadedly fitted to the rear end of the piston rod, while the small-sized stepped surface of the end cap fits onto the differential rod.

[0008] Specifically, the small-sized stepped surface of the body is provided with internal threads, and correspondingly, the outer side of the rear end of the piston rod is provided with external threads, and the two are connected by thread matching; and the large-sized stepped surface of the end cap is provided with internal threads, and correspondingly, the outer side of the rear end of the piston rod is provided with external threads, and the two are connected by thread matching.

[0009] Furthermore, the small-sized stepped surface of the end cap is recessed to form an annular groove, which accommodates a wear-resistant ring. The wear-resistant ring is sleeved on the differential rod and reciprocates relative to the differential rod.

[0010] Furthermore, the rear cover is provided with at least two oil ports.

[0011] Furthermore, at least one oil port is provided on the outer end face of the rear cover, and at least one oil port is provided on the outer peripheral face of the rear cover.

[0012] Specifically, the at least one oil port has a common pipe, and the end that communicates with the inside of the cylinder cavity is only one port.

[0013] Specifically, the rear cover is also provided with an air port and an oil drain hole that communicate with the rear cavity, with the air port facing upward and the oil drain hole facing downward.

[0014] Furthermore, the inner diameter of the blind groove of the piston rod is slightly larger than the outer diameter of the differential rod, so that there is a clearance between the differential rod and the inner wall of the blind groove of the piston rod.

[0015] Compared with the prior art, the present invention has at least the following beneficial effects:

[0016] 1. This utility model utilizes the fact that the effective area inside the differential cavity is smaller than that inside the front cavity. The differential cavity has a small area, and when the injection retraction occurs, the differential cavity is circulated with oil, which can reduce the consumption of hydraulic oil, save energy, effectively realize differential injection, and have a faster response speed. Moreover, the piston rod and differential rod are assembled through threads, making the structure more convenient to assemble, with a wider range of applications, and can well realize miniaturized production.

[0017] 2. This utility model has at least two oil ports in different directions reserved on the back cover. When one is connected, the other is blocked, which can increase the flexibility of installation when the processing site space is insufficient.

[0018] 3. This utility model has an oil drain hole in the rear cover to prevent oil leakage.

[0019] 4. This utility model leaves a clearance between the inner wall of the blind groove of the differential rod and the piston rod, which facilitates the machining of deep cavity drilling and reduces the machining accuracy requirements.

[0020] 5. This utility model is equipped with a wear-resistant ring, which is immersed in oil to reduce friction. Attached Figure Description

[0021] Figure 1 This is a schematic diagram of the rapid injection structure of the injection molding machine according to this utility model.

[0022] Figure 2 This is a cross-sectional view of the rapid injection structure of the injection molding machine according to this utility model.

[0023] Figure 3 This is a schematic diagram of the structure of this utility model applied to an injection molding machine.

[0024] Figure 4 This is a partial cross-sectional view of the present invention applied to an injection molding machine.

[0025] In the diagram: 100-Injection molding machine rapid injection structure, 10-Front cover, 13-First oil port, 20-Rear cover, 21-Second oil port, 23-Third oil port, 25-Air port, 27-Oil drain hole, 29-Port, 30-Cylinder barrel, 324-Front chamber, 326-Rear chamber, 40-Differential rod, 43-Connecting end of differential rod, 45-Suspended end of differential rod, 50-Piston rod, 51-Blind groove, 510-Clearing position, 512-Annular groove, 53-Rear end of piston rod, 56-Front end of piston rod, 60-Piston, 61-Body, 63-End cover;

[0026] 700 - Injection Molding Machine. Detailed Implementation

[0027] To facilitate understanding of this utility model, the technical solutions and advantages of the utility model will be further described in detail below with reference to the accompanying drawings and embodiments. Any mechanisms or methods not elaborated in this utility model can be referred to in the prior art. The specific structures and features of this utility model are illustrated below by way of example and should not constitute any limitation on this utility model. Furthermore, any technical feature mentioned below (including implicit or disclosed features), as well as any technical feature directly shown or implied in the figures, can be arbitrarily combined or deleted among these technical features to form more other embodiments that may not be directly or indirectly mentioned in this utility model. The accompanying drawings show preferred embodiments of this utility model. However, this utility model can be implemented in many different forms and is not limited to the embodiments described herein. Rather, these embodiments are provided to provide a more thorough and complete understanding of the disclosure of this utility model.

[0028] like Figure 1-4 As shown, the rapid injection structure 100 of the injection molding machine in this embodiment includes a front cover 10, a rear cover 20, a cylinder 30, a differential rod 40, a piston rod 50, and a piston 60.

[0029] Specifically, the cylinder barrel 30 is located between the front cover 10 and the rear cover 20. The front cover 10 and the rear cover 20 respectively seal both ends of the cylinder barrel 30, forming a closed cylinder cavity inside the cylinder barrel 30. The front cover 10 is provided with a first oil port 13 connected to the cylinder cavity, and the rear cover 20 is provided with a second oil port 21, a third oil port 23, an air port 25, and an oil drain hole 27 respectively connected to the cylinder cavity. The air port 25 faces upward, and the oil drain hole 27 faces downward.

[0030] In this preferred embodiment, the second oil port 21 and the third oil port 23 share a common pipe, and the end that communicates with the inside of the cylinder cavity is only a port 29. The second oil port 21 is located on the outer end face of the rear cover 20, and the third oil port 23 is located on the outer peripheral surface of the rear cover 20.

[0031] The differential rod 40 is a hollow tubular shape and is placed inside the cylinder cavity. One end of the differential rod 40 is fixedly connected to the rear cover 20, which is the connecting end 43 of the differential rod. The other end of the differential rod 40 extends from the front cover 10 and is suspended in the air, which is the suspended end 45 of the differential rod. The connecting end 43 of the differential rod is connected to the second oil port 21 and the third oil port 23 through port 29.

[0032] The piston rod 50 is sleeve-shaped, with a coaxial blind groove 51 at one end, which is the rear end 53 of the piston rod. The differential rod 40 is fitted into the blind groove 51, so that the rear end 53 of the piston rod is placed inside the cylinder cavity. The other end of the piston rod 50 is the front end 56, which penetrates the front cover 10 and extends outside the front cover 10. The hollow inner cavity of the differential rod 40 and the blind groove 51 of the piston rod 50 are interconnected through the suspended end 45 of the differential rod, so that the two together form the differential cavity of the injection mechanism.

[0033] In this preferred embodiment, the inner diameter of the blind groove 51 is slightly larger than the outer diameter of the differential rod 40, so that a clearance 510 is left between the differential rod 40 and the inner wall of the blind groove 51 of the piston rod 50. The clearance 510 is provided to facilitate the machining of deep cavity drilling and reduce the machining accuracy requirements.

[0034] A piston 60 is disposed within a cylindrical cavity and includes a body 61 and an end cap 63. The body 61 is an annular structure that houses the rear end 53 of the piston rod. Specifically, the inner surface of the body 61 has a stepped hole, including a small-sized stepped surface and a large-sized stepped surface. The small-sized stepped surface of the body 61 has internal threads, and correspondingly, the outer surface of the rear end 53 of the piston rod has external threads. The body 61 and the rear end 53 of the piston rod are connected by a threaded connection. The end cap 63 is housed within the large-sized stepped surface of the body 61. The end cap 63 is an annular structure with a stepped hole on its inner surface, including a small-sized stepped surface and a large-sized stepped surface. The large-sized stepped surface of the end cap 63 has internal threads, and correspondingly, the outer surface of the rear end 53 of the piston rod has external threads. The end cap 63 and the rear end 53 of the piston rod are connected by a threaded connection. The small-sized stepped surface of the end cap 63 is fitted with a differential rod 40. The end cap 63 serves as a lock nut to prevent loosening. The small stepped surface of the end cap 63 holds the differential rod 40, so that the differential rod 40 is suspended and centered in the blind groove 51 of the piston rod 50, ensuring that the outer side of the differential rod 40 and the blind groove 51 maintain a clearance position 510.

[0035] The outer diameter of the piston body 61 matches the inner diameter of the cylinder cavity. The piston fits tightly against the inner wall of the cylinder cavity, so that the piston body 61 seals the cylinder cavity into a front cavity 324 and a rear cavity 326. The front cavity 324 corresponds to the front cover 10, and the rear cavity 326 corresponds to the rear cover 20. The first oil port 13 connects to the front cavity 324, and the air port 25 and the oil drain hole 27 connect to the rear cavity 326.

[0036] In this preferred embodiment, the small-sized stepped surface of the end cap 63 is recessed to form an annular groove 512. The annular groove 512 accommodates a wear-resistant ring. The wear-resistant ring is sleeved on the differential rod 40 and reciprocates relative to the differential rod 40. The wear-resistant ring is immersed in oil to reduce friction.

[0037] The working principle of this invention is as follows: During injection molding, the first oil port 13 is connected to pressurized oil, the air port 25 is connected to atmospheric air, and one of the second oil port 21 and the third oil port 23 is connected to return oil. The other of the second oil port 21 and the third oil port 23 is plugged. Oil entering through the first oil port 13 pushes the piston towards the rear cover 20. The piston rod 50 drives the extrusion screw to move towards the rear cover 20 together. The extrusion screw injects the rubber material from the barrel into the mold, completing the injection process. Because injection needs to overcome mold cavity pressure and all flow channel resistance, the piston diameter is relatively large, increasing the injection force by increasing the effective area.

[0038] During injection retraction, oil enters the differential chamber through the second oil port 21 or the third oil port 23. The continuous oil supply generates a reaction force that causes the piston rod 50 to slide towards the front cover 10, thereby moving the extrusion screw of the injection molding machine 700 and completing the injection retraction action. At the same time, the hydraulic oil in the front chamber 324 is discharged from the first oil port 13.

[0039] In traditional hydraulic cylinders, oil accumulates at the piston opening, resulting in a large injection area and requiring a larger oil volume. In this embodiment, because the working area within the differential chamber is smaller than that within the front chamber, the differential chamber, with its smaller area, allows oil to flow through it during injection retraction, reducing hydraulic oil consumption, saving energy, effectively achieving differential injection, and providing a faster response speed.

[0040] Compared to existing technologies, where differential cylinders can only be assembled with screws in a fixed order or direction, the piston rod and piston in this embodiment are connected by threads, making assembly more convenient, applicable to a wider range of situations, and well-suited for miniaturized production. Furthermore, this embodiment features two oil ports in different directions on the rear cover; when one is connected, the other is blocked, increasing installation flexibility even in space-constrained environments. Additionally, an oil drain hole on the rear cover prevents oil leakage.

[0041] The above embodiments are merely preferred embodiments of the present utility model and should not be construed as limiting the scope of protection of the present utility model. For those skilled in the art, it will be understood that various changes, modifications, substitutions and variations can be made to these embodiments without departing from the principles and spirit of the present utility model. The scope of the present utility model is defined by the appended claims and their equivalents.

Claims

1. A flexible assembly rapid injection structure for an injection molding machine, characterized in that, The device includes a front cover, a rear cover, a cylinder barrel, a differential rod, a piston rod, and a piston. The front and rear covers respectively seal both ends of the cylinder barrel, forming a closed cylindrical cavity inside the cylinder barrel. The differential rod is a hollow tube, with one end fixedly connected to the rear cover and communicating with the oil port located on the rear cover, and the other end extending towards the front cover. The rear end of the piston rod has a blind groove, which fits onto the differential rod. The hollow inner cavity of the differential rod and the blind groove of the piston rod are interconnected through the suspended end of the differential rod to form a differential cavity. The front end of the piston rod extends outside the front cover. The piston is threadedly fitted onto the rear end of the piston rod, and the piston is in close contact with the inner wall of the cylindrical cavity, so that the piston seals and divides the cylindrical cavity into a front cavity and a rear cavity. The oil port located on the front cover communicates with the front cavity.

2. The flexible assembly injection molding machine rapid injection structure as described in claim 1, characterized in that, The piston includes a ring-shaped body and an end cap; the inner surface of the body is a stepped hole, and the small stepped surface of the body is threadedly fitted to the rear end of the piston rod; the large stepped surface of the body houses the end cap, the inner surface of the end cap is a stepped hole, and the large stepped surface of the end cap is threadedly fitted to the rear end of the piston rod, while the small stepped surface of the end cap fits onto the differential rod.

3. The flexible assembly injection molding machine rapid injection structure as described in claim 2, characterized in that, The small-sized stepped surface of the main body is provided with internal threads, and correspondingly, the outer side of the rear end of the piston rod is provided with external threads, and the two are connected by thread matching; and the large-sized stepped surface of the end cap is provided with internal threads, and correspondingly, the outer side of the rear end of the piston rod is provided with external threads, and the two are connected by thread matching.

4. The flexible assembly injection molding machine rapid injection structure as described in claim 2, characterized in that, The small-sized stepped surface of the end cap is recessed to form an annular groove, which accommodates a wear-resistant ring. The wear-resistant ring is sleeved on the differential rod and reciprocates relative to the differential rod.

5. The flexible assembly injection molding machine rapid injection structure as described in claim 1, characterized in that, The rear cover has at least two oil ports.

6. The flexible assembly injection molding machine rapid injection structure as described in claim 5, characterized in that, At least one oil port is provided on the outer end face of the rear cover, and at least one oil port is provided on the outer peripheral face of the rear cover.

7. The flexible assembly injection molding machine rapid injection structure as described in claim 5, characterized in that, The at least one oil port has a common pipe, and the end that communicates with the inside of the cylinder cavity has only one port.

8. The flexible assembly injection molding machine rapid injection structure as described in claim 1, characterized in that, The rear cover is also provided with an air port and an oil drain hole that connect to the rear cavity, with the air port facing upward and the oil drain hole facing downward.

9. The flexible assembly injection molding machine rapid injection structure as described in claim 1, characterized in that, The inner diameter of the blind groove of the piston rod is slightly larger than the outer diameter of the differential rod, so that there is a clearance between the differential rod and the inner wall of the blind groove of the piston rod.

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