Ejector sleeve ejector rod for injection mold
By designing ejector pins for injection molds and adopting a unique structure consisting of an outer ejector pin, a first ejector pin, an inner ejector pin, a second ejector pin, an ejector plate, and a backing plate, one-time demolding of blind hole products is achieved. This solves the problem of manual demolding or the need to add demolding mechanisms in existing technologies, and improves production efficiency.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2025-05-08
- Publication Date
- 2026-04-07
AI Technical Summary
When dealing with products with blind holes, existing injection molds often require manual demolding assistance or additional demolding mechanisms, resulting in high labor costs and low production efficiency.
Design an ejector pin for injection molds, including an outer ejector sleeve, a first ejector pin, an inner ejector sleeve, a second ejector pin, an ejector plate, and a backing plate. Through a unique through-hole structure, the outer and inner ejector sleeves can move synchronously and secondaryly between the first and second ejector pins, achieving one-time demolding.
No manual assistance or complex mechanisms are required for demolding, which reduces labor costs, improves production efficiency, and simplifies the demolding process.
Smart Images
Figure CN224089573U_ABST
Abstract
Description
Technical Field
[0001] This utility model belongs to the field of injection molding technology, and specifically relates to an ejector pin for injection molds. Background Technology
[0002] Injection molds, as a crucial molding tool, occupy a central position in the large-scale production of plastic products. They are precision devices used to transform thermoplastic or thermosetting plastic materials into plastic products of various shapes, sizes, and functions through injection molding. In injection molds, ejector pins are commonly used to mold circular through holes or blind holes on the product to avoid damage to the inner and outer walls of these holes during demolding.
[0003] Currently, the ejector pins commonly used in injection molding mainly consist of two parts: the ejector sleeve (outer tube) and the ejector inner pin (inner core). During demolding, as the injection molding machine ejects, the ejector sleeve, driven by the ejector plate, pushes the product out of the ejector inner pin. However, this structure is susceptible to problems when encountering similar... Figure 1 When the product has blind holes, it's impossible to eject the product from the ejector pins in one go. This often necessitates additional steps, such as manual demolding or the addition of an extra demolding mechanism. Adding manual demolding not only increases labor costs but also results in significantly lower efficiency compared to automated mechanical operation, extending the entire injection molding production cycle. Adding an extra demolding mechanism, on the other hand, increases mold complexity and cost, requiring additional debugging and maintenance time, further reducing production efficiency. Utility Model Content
[0004] In order to solve the problems existing in the prior art, this utility model aims to provide an ejector pin for injection molds to realize the secondary demolding action.
[0005] To achieve the above-mentioned technical objectives and effects, this utility model is implemented through the following technical solution:
[0006] An ejector pin for an injection mold includes an outer ejector sleeve, a first ejector pin, an inner ejector sleeve, a second ejector pin, an ejector pin plate, and a backing plate. The outer ejector sleeve has a first through hole on its outer surface. The first ejector pin is slidably inserted into the outer ejector sleeve, and its outer surface also has a second through hole. The inner ejector sleeve is slidably inserted into the first ejector pin. The second ejector pin is slidably inserted into the inner ejector sleeve. The backing plate is fixed to the rear side of the ejector pin plate, and both are movably inserted between the first and second through holes. As the ejector pin plate and the backing plate move between the first and second through holes, the inner ejector sleeve can be driven to slide between the first and second ejector pins.
[0007] Further, the material of the outer cylinder and the inner cylinder adopts SKD61; the material of the first ejector rod and the second ejector rod adopts SKH51.
[0008] Further, the outer cylinder, the first ejector rod, the inner cylinder and the second ejector rod are all subjected to high-frequency quenching.
[0009] Further, the outer cylinder, the first ejector rod, the inner cylinder and the second ejector rod are all provided with hanging tables, and the hanging tables all adopt D-shaped.
[0010] Further, the outer cylinder and the first ejector rod all adopt double-section structures, and the upper section diameter is smaller than the lower section diameter.
[0011] Further, the outer cylinder and the first ejector rod are all provided with chamfers at the upper and lower section connecting positions.
[0012] Further, the first through hole and the second through hole are both square holes, and the width directions of the two are the same, but in the length direction, the length of the second through hole is greater than the length of the first through hole.
[0013] Further, the length direction groove walls of the first through hole and the second through hole are all subjected to polishing treatment, and the surface roughness Ra is not greater than 0.8 μm.
[0014] Further, the ejector rod plate and the gasket top plate are detachably connected through locking bolts.
[0015] Further, the ejector rod plate and the gasket are provided with a positioning structure.
[0016] The beneficial effects of the present application are as follows: through the unique structure design of the outer cylinder, the first ejector rod, the inner cylinder, the second ejector rod, the ejector rod plate and the gasket, in cooperation with the setting of the first through hole and the second through hole, the outer cylinder and the inner cylinder can be synchronously moved between the first ejector rod and the second ejector rod for one-time demolding, and the inner cylinder can be moved between the first ejector rod and the second ejector rod for two-time demolding, thus effectively solving the problem that the existing ejector rod cannot be demolded once when facing a blind hole product, achieving the demolding without additional manual assistance or increasing a complex demolding mechanism, reducing the labor cost and improving the production efficiency.
[0017] The above description is only a summary of the technical scheme of the present application, in order to more clearly understand the technical means of the present application, and the content of the specification can be implemented, the following is a preferred embodiment of the present application and the detailed description of the drawings. The specific implementation of the present application is given in detail by the following examples and their drawings. BRIEF DESCRIPTION OF DRAWINGS
[0018] The accompanying drawings, which are included to provide a further understanding of the present invention and form part of this application, illustrate exemplary embodiments of the present invention and, together with the description thereof, serve to explain the present invention and do not constitute an undue limitation thereof. In the drawings:
[0019] Figure 1 This is a schematic diagram of the product structure for reference to this utility model;
[0020] Figure 2 This is a schematic diagram of the overall structure of the ejector rod of this utility model;
[0021] Figure 3 This is a sectional view of the ejector rod of this utility model;
[0022] Figure 4 This utility model Figure 3 Enlarged view of point A in the middle;
[0023] Figure 5 This is a schematic diagram of the present invention before demolding;
[0024] Figure 6 This is a schematic diagram of the present invention after one demolding.
[0025] Figure 7 This is a schematic diagram of the present invention after secondary demolding.
[0026] The following are the labels in the diagram: 1. Outer sleeve; 2. First push rod; 3. Inner sleeve; 4. Second push rod; 5. Push rod plate; 6. Pad plate; 7. Hanging platform; 8. Locking bolt; 9. Positioning pin; 10. Positioning hole; 11. First through hole; 21. Second through hole. Detailed Implementation
[0027] The present invention will now be described in detail with reference to the accompanying drawings and embodiments.
[0028] It should be noted that all directional indicators (such as up, down, left, right, front, back, upper end, lower end, top, bottom, etc.) in this utility model embodiment are only used to explain the relative positional relationship and movement of each component in a certain specific posture (as shown in the figure). If the specific posture changes, the directional indicator will also change accordingly.
[0029] See Figures 2-3As shown, an ejector pin for an injection mold includes an outer ejector sleeve 1, a first ejector pin 2, an inner ejector sleeve 3, a second ejector pin 4, an ejector plate 5, and a pad 6. The outer ejector sleeve 1 has a first through hole 11 on its outer surface. The first ejector pin 2 is slidably inserted into the outer ejector sleeve 1, and its outer surface has a second through hole 21. The inner ejector sleeve 3 is slidably inserted into the first ejector pin 2. The second ejector pin 4 is slidably inserted into the inner ejector sleeve 3. The pad 6 is fixed to the rear side of the ejector plate 5, and both are movably inserted between the first through hole 11 and the second through hole 21. As the ejector plate 5 and the pad 6 move between the first through hole 11 and the second through hole 21, the inner ejector sleeve 3 can be driven to slide between the first ejector pin 2 and the second ejector pin 4.
[0030] Furthermore, in this embodiment, the outer sleeve 1 and the inner sleeve 3 are made of SKD61; the first push rod 2 and the second push rod 4 are made of SKH51; and the outer sleeve 1, the first push rod 2, the inner sleeve 3 and the second push rod 4 are all subjected to high-frequency quenching to improve wear resistance.
[0031] Furthermore, in this embodiment, the outer sleeve 1, the first push rod 2, the inner sleeve 3, and the second push rod 4 are all provided with a mounting platform 7, and the mounting platform 7 is D-shaped, but not limited to D-shaped, and can also be other shapes, such as: oblong hole shape, square shape, etc.; and the outer sleeve 1 and the first push rod 2 are both adopted with a double-section structure, and the diameter of the upper section is smaller than the diameter of the lower section, and chamfers are provided at the connection between the upper and lower sections of the outer sleeve 1 and the first push rod 2.
[0032] Furthermore, in this embodiment, both the first through hole 11 and the second through hole 21 are square holes, and their width directions are the same. However, in the length direction, the length of the second through hole 21 is greater than the length of the first through hole 11. During processing, the groove walls in the length direction of both the first through hole 11 and the second through hole 21 are polished, and the surface roughness Ra is no greater than 0.8μm, so as to reduce the frictional resistance of the top rod plate 5 and the pad plate 6 during the movement and ensure smooth movement.
[0033] Further, see Figures 3-4As shown, in this embodiment, the top plate 5 and the top plate 6 are detachably connected by locking bolts 8. To prevent misalignment between the top plate 5 and the top plate 6, which would affect movement within the first through hole 11 and the second through hole 21, a positioning structure is provided between the top plate 5 and the top plate 6. In this embodiment, the positioning structure is a pin-hole positioning structure. When set, the positioning pin 9 is located on the top plate 6, and the positioning hole 10 is located on the top plate 5. Of course, the above pin-hole setting method is only one implementation method and is not intended to limit the scope of this application. In other cases, the positioning hole 10 may be located on the top plate 6, while the positioning pin 9 may be located on the top plate 5.
[0034] The working principle of this utility model is as follows:
[0035] In use, after machining the corresponding shape at the top of the ejector pin, install it into the mold frame; for demolding, please refer to the following for details. Figures 5-6 As shown in the figure, only the connection diagram between the ejector pin and part of the mold frame is shown. In the figure, A represents the mold frame; B represents the ejector pin; and C represents the product.
[0036] When molding is complete, our ejector pin connects to the product, as shown in the image. Figure 5 As shown; during demolding, the injection molding machine moves the ejector plate of the mold base within it, thereby causing the outer sleeve 1 to move upward along the first ejector pin 2 and the inner sleeve 3 along the first ejector pin 2 and the second ejector pin 4, thus causing the product to move upward synchronously, thereby removing the front end shapes of the first ejector pin 2 and the second ejector pin 4 from the product structure, achieving demolding in one step, as shown. Figure 6 As shown; then, under the continued drive of the template, the inner sleeve 3 continues to move upward along the first ejector pin 2 and the second ejector pin 4, thereby driving the product to move upward synchronously, thus realizing the removal of the front end shape of the outer sleeve 1 from the product structure, achieving secondary demolding, as shown. Figure 7 As shown; this allows the product to be removed from the company's top rod.
[0037] The above description is merely a preferred embodiment of this utility model and is not intended to limit the utility model. Various modifications and variations can be made to this utility model by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of this utility model should be included within the protection scope of this utility model.
Claims
1. A push rod for an injection mold, characterized in that: The device includes an outer sleeve (1), a first push rod (2), an inner sleeve (3), a second push rod (4), a push rod plate (5), and a pad (6). The outer sleeve (1) has a first through hole (11) on its outer surface. The first push rod (2) is slidably inserted into the outer sleeve (1), and a second through hole (21) is opened on its outer surface. The inner sleeve (3) is slidably inserted into the first push rod (2). The second push rod (4) is slidably inserted into the inner sleeve (3). The pad (6) is fixed to the rear side of the push rod plate (5), and the two are movably inserted between the first through hole (11) and the second through hole (21). As the push rod plate (5) and the pad (6) move between the first through hole (11) and the second through hole (21), the inner sleeve (3) can be driven to slide between the first push rod (2) and the second push rod (4).
2. The ejector pin for injection molds according to claim 1, characterized in that: The outer sleeve (1) and the inner sleeve (3) are made of SKD61; the first push rod (2) and the second push rod (4) are made of SKH51.
3. The ejector pin for injection molds according to claim 1, characterized in that: The outer sleeve (1), the first push rod (2), the inner sleeve (3), and the second push rod (4) are all subjected to high-frequency quenching.
4. The ejector pin for injection molds according to claim 1, characterized in that: The outer sleeve (1), the first push rod (2), the inner sleeve (3) and the second push rod (4) are all provided with a mounting platform (7), and the mounting platform (7) is D-shaped.
5. The ejector pin for injection molds according to claim 1, characterized in that: Both the outer sleeve (1) and the first push rod (2) adopt a double-section structure, and the diameter of the upper section is smaller than that of the lower section.
6. The ejector pin for injection molds according to claim 5, characterized in that: Both the upper and lower sections of the outer sleeve (1) and the first top rod (2) are chamfered.
7. The ejector pin for injection molds according to claim 1, characterized in that: Both the first through hole (11) and the second through hole (21) are square holes, and their width directions are the same, but in the length direction, the length of the second through hole (21) is greater than the length of the first through hole (11).
8. The ejector pin for injection molds according to claim 7, characterized in that: The longitudinal groove walls of the first through hole (11) and the second through hole (21) are both polished, and the surface roughness Ra is no greater than 0.8 μm.
9. The ejector pin for injection molds according to claim 1, characterized in that: The top plate (5) and the pad plate (6) are detachably connected by locking bolts (8).
10. The ejector pin for injection molds according to claim 1, characterized in that: A positioning structure is provided between the top rod plate (5) and the pad plate (6).