Vacuumizing device of injection mold

Abstract

The invention discloses a vacuumizing device of an injection mold. The vacuumizing device comprises a movable mold plate, a fixed mold plate, a vacuum pump and an ejector pin mechanism, the movable mold plate and the fixed mold plate are closed to form a cavity; an air exhaust channel communicated with the cavity is formed in the fixed mold plate, and the vacuum pump is communicated with the air exhaust channel through a pipeline; the ejector pin mechanism comprises an ejector pin plate and an ejector pin, the bottom end of the ejector pin is fixedly connected with the ejector pin plate, the top end of the ejector pin penetrates through the fixed mold plate and extends into the mold cavity, an ejector pin hole allowing the ejector pin to penetrate through is formed in the fixed mold plate, a plurality of sealing ring mounting grooves are formed in the hole wall of the ejector pin hole, and sealing rings are mounted in the sealing ring mounting grooves correspondingly; the ejector pin is provided with a plurality of reducing sections in one-to-one correspondence with the sealing rings, the sealing rings are located above the corresponding reducing sections, and the sealing rings make close contact with the outer wall of the ejector pin. According to the vacuumizing device of the injection mold, the relative friction between the ejector pin and the sealing ring in the movement process is greatly reduced, so that the abrasion to the sealing ring is reduced, and the sealing performance between the ejector pin and the ejector pin hole is ensured.

Description

Technical Field

[0001] The invention relates to a vacuum pumping device for an injection mould. Background Art

[0002] Injection mold is a tool for producing plastic products, and it is also a tool that gives plastic products a complete structure and precise size. The injection mold consists of two parts: a movable mold and a fixed mold. The movable mold is installed on the movable template of the injection molding machine, and the fixed mold is installed on the fixed template of the injection molding machine. During injection molding, the movable mold and the fixed mold are closed to form a pouring system and a cavity. When the mold is opened, the movable mold and the fixed mold are separated to remove the plastic product. Injection molds are generally equipped with ejector mechanisms to facilitate the demolding of plastic products.

[0003] When the injection mold is in operation, there is a vacuuming step. However, in actual applications, since the ejector pin needs to be pushed into the plastic product, the ejector pin hole must be connected to the cavity. During the vacuuming process, if the ejector pin and the ejector pin hole cannot be completely sealed, air will enter between the ejector pin and the ejector pin hole during the vacuuming process, resulting in the inability to achieve the required vacuum degree in the cavity, which directly affects the quality of the plastic product. For this reason, a sealing ring is provided in the ejector pin hole in the prior art to enhance the sealing strength between the ejector pin and the ejector pin hole, thereby enhancing the vacuum degree in the cavity. However, since the ejector pin needs to move frequently, relative friction movement is generated between the ejector pin and the sealing ring, which accelerates the wear of the sealing ring, resulting in a decrease in the sealing effect and affecting the service life of the sealing ring. Summary of the invention

[0004] The object of the present invention is to provide a vacuum pumping device for an injection mold, which has a reasonable structure and greatly reduces the relative friction between the ejector pin and the sealing ring during movement, thereby reducing the wear on the sealing ring and ensuring the sealing between the ejector pin and the ejector pin hole, while being conducive to extending the service life of the sealing ring and avoiding frequent replacement of the sealing ring.

[0005] To achieve the above object, the technical solution of the present invention is to design a vacuum pumping device for an injection mold, comprising a movable mold plate, a fixed mold plate, a vacuum pump and an ejector mechanism; The movable template is arranged above the fixed template, and the movable template and the fixed template are closed to form a cavity; The interior of the fixed mold plate is provided with an air extraction channel connected to the mold cavity, and the vacuum pump is connected to the air extraction channel through a pipeline; The ejector mechanism comprises an ejector plate and an ejector, wherein the ejector plate is arranged below the fixed template, the bottom end of the ejector is fixedly connected to the ejector plate, and the top end of the ejector passes through the fixed template and extends into the cavity, an ejector hole is arranged inside the fixed template for the ejector to pass through, a plurality of sealing ring mounting grooves are arranged on the hole wall of the ejector hole, the plurality of sealing ring mounting grooves are arranged at equal intervals along the axial direction of the ejector, and sealing rings are respectively installed in the plurality of sealing ring mounting grooves, the ejector is provided with a plurality of reduced diameter sections corresponding to the sealing rings one by one, the sealing rings are located above the corresponding reduced diameter sections, and the sealing rings are in close contact with the outer wall of the ejector.

[0006] Preferably, the length of the reduced diameter section is the same as the stroke of the ejector pin.

[0007] Preferably, the top of the reduced diameter section is a transition slope structure.

[0008] Preferably, a one-way valve is provided on the pipeline.

[0009] Preferably, a panel is provided above the movable template.

[0010] Preferably, a bottom plate is provided below the ejector plate.

[0011] The advantages and beneficial effects of the present invention are as follows: a vacuum pumping device for an injection mold is provided, which has a reasonable structure and greatly reduces the relative friction between the ejector pin and the sealing ring during movement, thereby reducing the wear on the sealing ring, ensuring the sealing between the ejector pin and the ejector pin hole, and at the same time is conducive to extending the service life of the sealing ring and avoiding frequent replacement of the sealing ring. BRIEF DESCRIPTION OF THE DRAWINGS

[0012] Figure 1 It is a schematic diagram of the present invention.

[0013] Figure 2 This Figure 1 Enlarged view of point A in the middle. DETAILED DESCRIPTION

[0014] The specific implementation of the present invention is further described below in conjunction with the accompanying drawings and embodiments. The following embodiments are only used to more clearly illustrate the technical solution of the present invention, and cannot be used to limit the protection scope of the present invention.

[0015] The technical solution specifically implemented in the present invention is: like Figure 1 and Figure 2 As shown, a vacuum pumping device for an injection mold comprises a movable mold plate 1, a fixed mold plate 2, a vacuum pump 3 and an ejector mechanism; The movable die plate 1 is arranged above the fixed die plate 2, and the movable die plate 1 and the fixed die plate 2 are closed to form a cavity 4; The interior of the fixed mold plate 2 is provided with an exhaust passage 5 connected to the mold cavity 4, and the vacuum pump 3 is connected to the exhaust passage 5 through a pipeline 6; The ejector mechanism comprises an ejector plate 7 and an ejector 8, wherein the ejector plate 7 is arranged below the fixed mold plate 2, the bottom end of the ejector 8 is fixedly connected to the ejector plate 7, and the top end of the ejector 8 passes through the fixed mold plate 2 and extends into the cavity 4, an ejector hole 9 is arranged inside the fixed mold plate 2 for the ejector 8 to pass through, a plurality of sealing ring mounting grooves 10 are arranged on the hole wall of the ejector hole 9, the plurality of sealing ring mounting grooves 10 are arranged at equal intervals along the axial direction of the ejector 8, and sealing rings 11 are respectively installed in the plurality of sealing ring mounting grooves 10, the ejector 8 is provided with a plurality of reduced diameter sections 12 corresponding to the sealing rings 11 one by one, the sealing rings 11 are located above the corresponding reduced diameter sections 12, and the sealing rings 11 are in close contact with the outer wall of the ejector 8.

[0016] Furthermore, the length of the reduced diameter section 12 is the same as the stroke of the ejector pin 8 .

[0017] Furthermore, the top of the reduced diameter section 12 is a transition slope structure 13 .

[0018] Furthermore, a one-way valve 14 is provided on the pipeline 6 , and the one-way valve 14 is used to control the one-way communication from the air extraction channel 5 to the vacuum pump 3 .

[0019] Furthermore, a panel 15 is provided above the movable template 1 .

[0020] Furthermore, a bottom plate 16 is provided below the ejector plate 7 .

[0021] The working principle of the vacuum pumping device of the injection mold of the present invention is as follows: During the injection molding process, when the movable platen 1 and the fixed platen 2 are molded together, the vacuum pump 3 is started to evacuate the cavity 4. By setting a sealing ring 11 in the ejector hole 9 to be in close contact with the outer wall of the ejector 8, the sealing between the ejector 8 and the ejector hole 9 is improved, and air is prevented from entering the cavity 4 from between the ejector 8 and the ejector hole 9 during the vacuuming process. After the injection molding is completed, the movable platen 1 and the fixed platen 2 are opened, and then the ejector plate 7 drives the ejector 8 upward and ejects the product in the cavity 4. During the upward movement of the ejector 8, the ejector 8 will be separated from the corresponding sealing ring 11 through the diameter reduction section 12, thereby greatly reducing the relative friction between the ejector 8 and the sealing ring 11 during the movement of the ejector 8, until the ejector 8 is in place, and the sealing ring 11 corresponds to the bottom end of the corresponding diameter reduction section 12. During the process of ejector pin 8 descending and resetting, ejector pin 8 will gradually squeeze corresponding sealing ring 11 and deform through transition slope structure 13 of diameter-reducing section 12, until ejector pin 8 descends to the right position, sealing ring 11 is separated from transition slope structure 13 of corresponding diameter-reducing section 12, and is in close contact with the outer wall of ejector pin 8 above corresponding diameter-reducing section 12, so as to ensure the sealing between ejector pin 8 and ejector hole 9, and prepare for the next vacuum injection molding.

[0022] The above is only a preferred embodiment of the present invention. It should be pointed out that for ordinary technicians in this technical field, several improvements and modifications can be made without departing from the technical principles of the present invention. These improvements and modifications should also be regarded as the scope of protection of the present invention.

Claims

1. A vacuum pumping device for an injection mold, characterized in that: It includes a movable platen, a fixed platen, a vacuum pump and an ejector mechanism; The movable template is arranged above the fixed template, and the movable template and the fixed template are closed to form a cavity; The interior of the fixed mold plate is provided with an air extraction channel connected to the mold cavity, and the vacuum pump is connected to the air extraction channel through a pipeline; The ejector mechanism comprises an ejector plate and an ejector, wherein the ejector plate is arranged below the fixed template, the bottom end of the ejector is fixedly connected to the ejector plate, and the top end of the ejector passes through the fixed template and extends into the cavity, an ejector hole is arranged inside the fixed template for the ejector to pass through, a plurality of sealing ring mounting grooves are arranged on the hole wall of the ejector hole, the plurality of sealing ring mounting grooves are arranged at equal intervals along the axial direction of the ejector, and sealing rings are respectively installed in the plurality of sealing ring mounting grooves, the ejector is provided with a plurality of reduced diameter sections corresponding to the sealing rings one by one, the sealing rings are located above the corresponding reduced diameter sections, and the sealing rings are in close contact with the outer wall of the ejector.

2. The vacuum pumping device for injection mold according to claim 1, characterized in that: The length of the reduced diameter section is the same as the stroke of the ejector pin.

3. The vacuum pumping device for injection mold according to claim 2, characterized in that: The top of the reduced diameter section is a transition slope structure.

4. The vacuum pumping device for injection mold according to claim 1, characterized in that: A one-way valve is arranged on the pipeline.

5. The vacuum pumping device for injection mold according to claim 1, characterized in that: A panel is arranged above the movable template.

6. The vacuum pumping device for injection mold according to claim 1, characterized in that: A bottom plate is arranged below the ejector plate.

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