Sprue insert structure for injection mold
By using a floating gate insert design in the injection mold, which is locked by the extruder and floats when the mold opens, the problem of product tearing caused by insufficient gate insert height is solved, and the molding quality of the product is improved.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- NINGHAI FIRST RATE INJECTION MOULD FACTORY
- Filing Date
- 2025-06-16
- Publication Date
- 2026-07-14
AI Technical Summary
In existing injection molds, the gate insert is prone to damage to the product during demolding due to insufficient ejection height, which affects product quality.
A floating structure is used to install the gate insert. The extrusion component locks the insert when the mold is closed and unlocks it when the mold is opened. The gate insert floats slightly using elastic components or limit bolts, reducing the force between the gate and the product.
It effectively reduces the adhesion between the gate insert and the product, avoids tearing during demolding, and ensures product quality.
Smart Images
Figure CN224489884U_ABST
Abstract
Description
Technical Field
[0001] This application relates to the field of mold technology, and in particular to a gate insert structure for an injection mold. Background Technology
[0002] The gate insert is a key component in mold design. It is a replaceable part installed on the mold and is usually located in the transition area between the end of the runner and the cavity. It directly determines the shape, size, and location of the gate, affecting the material filling speed, flow direction, and molding quality.
[0003] like Figure 1 As shown, this is a thin-shell injection molded product structure; such as Figure 2 As shown, after the mold is formed and ejected, the product and the gate are connected. However, before ejection, there is a significant force between the gate insert and the gate, resulting in insufficient gate height. Consequently, during product demolding, defects such as product tearing can easily occur, affecting product quality. Therefore, how to improve the existing gate insert to overcome these problems is a problem that urgently needs to be solved by those skilled in the art. Utility Model Content
[0004] One of the objectives of this application is to provide a gate insert structure for an injection mold.
[0005] To achieve the above objectives, the technical solution adopted in this application is as follows: a gate insert structure for an injection mold, comprising a mold body, a gate insert, and an extruder. The mold body includes an upper mold and a lower mold. The gate insert is installed in the lower mold via a floating structure. The extruder is installed in the upper mold and corresponds to and cooperates with the gate insert. After mold closing, the extruder abuts against the gate insert and locks it. After mold opening, the extruder moves away from the gate insert and releases it from the lock. Consequently, the gate insert floats away from the product under the action of the floating structure, thereby reducing the force on the gate insert.
[0006] Preferably, the floating structure includes a groove and an elastic element. The groove is disposed within the lower mold, and the gate insert is horizontally floating and installed within the groove and connected to the lower mold via the elastic element.
[0007] Preferably, the floating structure includes a limiting groove, a limiting bolt, and an elastic element. The limiting groove is disposed within the lower mold. The two sides of the gate insert abut against the two sides of the limiting groove. The gate insert is adapted to be installed in the limiting groove by the limiting bolt. The limiting bolt is clearance-fitted with the gate insert, and the screw head of the limiting bolt is adapted to limit the gate insert vertically. The gate insert is adapted to be connected to the lower mold by the elastic element.
[0008] Preferably, the elastic element includes a spring, with a first end of the spring connected to the gate insert and a second end of the spring connected to the lower mold.
[0009] Preferably, the elastic element is an elastic block made of an elastic material; after mold closing, the elastic block is adapted to deform and store energy; after mold opening, the elastic block is adapted to release energy and restore its deformation.
[0010] Preferably, both the gate insert and the lower mold are fitted with corresponding sleeves, and the two ends of the spring are sleeved with the corresponding sleeves.
[0011] Preferably, the gate insert has a through-hole and a connected upper hole, the limiting bolt is installed in the lower hole and the screw head is located in the upper hole, and a sealing block flush with the gate insert is installed at the top of the upper hole.
[0012] Preferably, the side of the gate insert is provided with a bevel, and the extruder is adapted to lock the gate insert by wedge extrusion.
[0013] Compared with the prior art, the beneficial effects of this application are as follows:
[0014] This invention installs the gate insert in the mold through a floating structure. After the mold is opened, the gate insert can float and move back slightly to reduce the force between the gate insert and the gate. This effectively reduces defects such as product tearing caused by insufficient gate height during product demolding and ensures the molding quality of the product. Attached Figure Description
[0015] Figure 1 This is a schematic diagram of the product structure of this utility model.
[0016] Figure 2 This is a schematic diagram showing the gate insert of this utility model when it is fitted with the product.
[0017] Figure 3 This is a partial cross-sectional view of the present invention.
[0018] Figure 4 This is a schematic diagram of the installation structure of the limiting bolt and the gate insert of this utility model.
[0019] Figure 5 This is a three-dimensional structural diagram of the gate insert and the extrusion part of this utility model.
[0020] In the diagram: 1. Product; 2. Gate insert; 3. Gate; 4. Extrusion part; 5. Lower mold; 6. Limit bolt; 7. Upper hole; 8. Lower hole; 9. Sealing block; 10. Sleeve; 11. Spring. Detailed Implementation
[0021] The present application will be further described below with reference to specific embodiments. It should be noted that, without conflict, the various embodiments or technical features described below can be arbitrarily combined to form new embodiments.
[0022] In the description of this application, it should be noted that the terms "center", "lateral", "longitudinal", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "clockwise", "counterclockwise", etc., which indicate the orientation and positional relationship based on the orientation or positional relationship shown in the accompanying drawings, are only for the convenience of describing this application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and should not be construed as limiting the specific protection scope of this application.
[0023] It should be noted that the terms "first," "second," etc., in the specification and claims of this application are used to distinguish similar objects and are not necessarily used to describe a specific order or sequence.
[0024] Further analysis of the shortcomings of the existing gate insert 2 (especially for thin-shell and deep-cavity products 1): It should be noted that during injection molding, the molten plastic is injected at high speed from the gate 3 into the cavity of the mold body and reaches the set pressure. Then, during cooling, the shrinkage of the plastic at the gate 3 will generate high concentrated stress at this point. This will cause a strong adhesion between the gate 3 of product 1 and the gate insert 2. Therefore, during ejection, the gate 3 is easily not ejected high enough, which can easily damage product 1 during demolding and cause product 1 to be defective.
[0025] Therefore, the inventors of this application have developed a gate insert structure for an injection mold, one embodiment of which is, for example... Figures 1 to 5 As shown, the mold includes a mold body, a gate insert 2, and an extrusion part 4. The mold body includes an upper mold and a lower mold 5. The gate insert 2 is installed in the lower mold 5 through a floating structure. The extrusion part 4 is installed in the upper mold and corresponds to and cooperates with the gate insert 2.
[0026] It is understandable that during mold closing, such as Figure 5As shown, the upper mold moves the extruder 4 downwards and abuts against the gate 3, thereby limiting and locking the position of the gate insert 2, ensuring that the gate insert 2 corresponds and engages with the cavity of the mold body. After mold opening, the extruder 4 moves away from the gate insert 2 under the action of the upper mold, thus releasing the lock on the gate insert 2. At this time, the gate insert 2 floats away from the product 1 under the action of the floating structure, moving a small distance (generally 0.5mm-2mm). This means that the subsequent movement applies a reverse pulling force to the plastic at the gate 3, partially offsetting the stress in that area, thereby reducing the adhesion between the gate 3 and the gate insert 2. In this way, the gate 3 is more easily ejected during the ejection process, avoiding the problem of insufficient ejection height of the gate 3, thus effectively reducing the risk of damaging the product 1 during demolding and ensuring the quality of the product 1.
[0027] This application does not limit the specific structure of the floating structure; the following two specific embodiments are provided for reference:
[0028] Structure 1: The floating structure includes a slide groove and an elastic element. The slide groove is located inside the lower mold 5, and the gate insert 2 is horizontally floating (sliding) installed in the slide groove and connected to the lower mold 5 through the elastic element. Alternatively, it can be understood that the gate insert 2 is horizontally sliding in the slide groove through the elastic element, and the distance it can slide is the micro-motion distance mentioned above.
[0029] It is understandable that after the mold is closed, the elastic element is in a state of compression deformation; after the mold is opened, the gate insert 2 will move slightly away from the product 1 along the slide under the action of the elastic element, thereby effectively reducing some of the stress at the gate 3 and facilitating the subsequent ejection operation.
[0030] Structure 2 (e.g.) Figure 3 and Figure 4 (As shown): The floating structure includes a limiting groove, limiting bolts 6, and an elastic element. The limiting groove is located inside the lower mold 5. The two sides of the gate insert 2 abut against the two sides of the limiting groove. A screw hole is provided on the bottom side of the limiting groove. The limiting bolts 6 install the gate insert 2 into the limiting groove through the screw hole. At this time, the screw head of the limiting bolt 6 limits the vertical direction of the gate insert 2, while the screw rod of the limiting bolt 6 and the gate insert 2 have a clearance fit. In other words, the gate insert 2 cannot move up or down, and is limited on both sides by the limiting groove, therefore it can only float in one direction.
[0031] Furthermore, the specific installation method of the gate insert is as follows: Figure 3 and Figure 4As shown, an upper hole 7 and a lower hole 8 are connected and pass through the gate insert 2. The screw portion of the limiting bolt 6 is installed in the lower hole 8, and its screw head is located in the upper hole 7. That is to say, the diameter of the upper hole 7 is larger than the diameter of the lower hole 8. A sealing block 9, flush with the gate insert 2, is installed at the top of the upper hole 7 to prevent molten plastic from entering the upper hole 7 and causing blockage during the injection molding process.
[0032] It should be noted that Structure 2 differs from Structure 1 only in its installation method; the principle of floating and retraction is the same, so it will not be elaborated further. We know that molds have complex internal structures, so component installation must prioritize ease of disassembly and replacement. Structure 1 directly floats the gate insert 2 within the slide, requiring a corresponding slider on the outside of the gate insert 2. The floating distance is also very small, making the slider and slide difficult to manufacture and installation / disassembly cumbersome. Structure 2, on the other hand, uses limiting bolts 6 and limiting grooves for installation, making it much simpler. Therefore, Structure 2 is the preferred method.
[0033] In this embodiment, the elastic element has various structures, including but not limited to the following two:
[0034] Structure 1: such as Figure 5 As shown, the elastic element includes a spring 11, with its first end connected to the gate insert 2 and its second end connected to the lower mold 5. It should be understood that when the gate insert 2 is locked under the action of the extruder 4, the spring 11 is compressed; when the extruder 4 loses its extruding effect on the gate insert 2, the spring 11 will cause the gate insert 2 to float.
[0035] Furthermore, in order to facilitate the installation and disassembly of the spring 11, sleeves 10 are installed at corresponding positions on the gate insert 2 and the lower mold 5. The sleeves 10 are fitted onto both ends of the spring 11 to limit the ends of the spring 11 and prevent the spring 11 from shifting or falling off during the extension and retraction process, thereby ensuring the stability and reliability of the spring 11.
[0036] Structure 2: The elastic element is an elastic block made of an elastic material, such as high-temperature resistant silicone rubber, fluororubber, or urethane. Understandably, during mold closing, when the gate insert 2 is in a squeeze-locked state, the elastic element deforms and stores energy under the squeezing action; after mold opening, the elastic block releases energy and returns to its original shape, thereby causing the gate insert 2 to move slightly (float).
[0037] It should be noted that both structures of the elastic element can meet the actual needs, and those skilled in the art can choose according to the actual situation.
[0038] In this embodiment, as Figure 4 and Figure 5 As shown, a slope is provided on the side of the gate insert 2. During mold closing, the extruder 4 moves downward and contacts the slope of the gate insert 2. Through the wedge-shaped extrusion action, the extruder 4 can gradually penetrate and drive the gate insert 2 to its limit position, thereby locking the gate insert 2. This slope design is simple and easy to achieve the fit between the two. Of course, in order to further improve the interaction force between the two during the fit, a corresponding slope is also provided on the side of the extruder 4, so that the contact area between the extruder 4 and the gate insert 2 gradually increases, improving the stability during locking.
[0039] The working principle of this invention is as follows: During mold closing, the extruder 4 moves downward and contacts the inclined surface of the gate insert 2. As the extruder 4 continues to move downward, its inclined surface engages with the inclined surface of the gate insert 2 in a wedge-shaped compression fit. This allows the extruder 4 to gradually penetrate deeper and apply a horizontal thrust to the gate insert 2, driving the gate insert 2 to move slightly along a preset direction until it reaches its limit position. At this point, the gate insert 2 is completely locked and forms a corresponding fit with the cavity of the mold body. After mold opening, the extruder 4 gradually moves away from the gate insert 2 under the action of the upper mold. At this time, the gate insert 2 begins to move slightly away from the product 1 under the action of the elastic element. This displacement is usually between 0.5mm and 2mm, thereby applying a reverse pulling force to the plastic at the gate 3, thus partially offsetting the stress in this area and reducing the adhesion between the gate 3 and the gate insert 2. In this way, when the ejection operation is performed after injection molding, gate 3 is more easily ejected, avoiding the problem of insufficient ejection height of gate 3, thereby effectively reducing the risk of tearing product 1 during demolding and ensuring the integrity and quality of product 1.
[0040] The basic principles, main features, and advantages of this application have been described above. Those skilled in the art should understand that this application is not limited to the above embodiments. The embodiments and descriptions in the specification are merely the principles of this application. Various changes and modifications can be made to this application without departing from its spirit and scope, and all such changes and modifications fall within the scope of the claims. The scope of protection claimed by this application is defined by the appended claims and their equivalents.
Claims
1. A gate insert structure for an injection mold, characterized in that, include: The mold body includes an upper mold and a lower mold; A gate insert, wherein the gate insert is mounted in the lower mold via a floating structure; as well as An extrusion component is installed inside the upper mold and corresponds to and cooperates with the gate insert. After the mold is closed, the extrusion component abuts against the gate insert and locks it. After the mold is opened, the extrusion component moves away from the gate insert and releases it. As a result, the gate insert floats away from the product under the action of the floating structure to reduce the force on the gate insert.
2. The gate insert structure of the injection mold as described in claim 1, characterized in that: The floating structure includes a slide and an elastic element. The slide is disposed in the lower mold, and the gate insert is horizontally floating and installed in the slide and connected to the lower mold through the elastic element.
3. The gate insert structure of the injection mold as described in claim 2, characterized in that: The floating structure includes a limiting groove, a limiting bolt, and an elastic element. The limiting groove is disposed in the lower mold. The two sides of the gate insert abut against the two sides of the limiting groove. The gate insert is adapted to be installed in the limiting groove by the limiting bolt. The limiting bolt and the gate insert are clearance-fitted, and the screw head of the limiting bolt is adapted to limit the gate insert in the vertical direction. The gate insert is adapted to be connected to the lower mold by the elastic element.
4. The gate insert structure of the injection mold as described in claim 2 or 3, characterized in that: The elastic element includes a spring, with a first end of the spring connected to the gate insert and a second end of the spring connected to the lower mold.
5. The gate insert structure of the injection mold as described in claim 2 or 3, characterized in that: The elastic element is an elastic block made of an elastic material; after the mold is closed, the elastic block is adapted to deform and store energy; after the mold is opened, the elastic block is adapted to release energy and restore its deformation.
6. The gate insert structure of the injection mold as described in claim 4, characterized in that: Both the gate insert and the lower mold are fitted with corresponding sleeves, and the two ends of the spring are sleeved with the corresponding sleeves.
7. The gate insert structure of the injection mold as described in claim 5, characterized in that: The gate insert has a through-hole and a connected upper hole and a lower hole. The limiting bolt is installed in the lower hole and the bolt head is located in the upper hole. A sealing block flush with the gate insert is installed at the top of the upper hole.
8. The gate insert structure of the injection mold as described in claim 1, characterized in that: The gate insert has a beveled side, and the extruder is adapted to lock the gate insert by wedge extrusion.