A two-stage ejection demoulding device

Abstract

The present invention relates to the field of mold technology, and provides a two-stage ejection demoulding device, comprising a two-stage push plate and a one-stage push plate sandwiched between a movable mold and a movable platen; the two-stage push plate and the one-stage push plate can reciprocate between the movable mold and the movable platen; a one-stage ejector block is movably embedded in one side of the movable mold; a two-stage ejector block is movably embedded in the one-stage ejector block; the two-stage ejector block is connected to an inclined ejector rod; a clearance cavity and a guide cavity for the inclined ejector rod to pass through and are interconnected are provided in the movable mold; a guide slider is slidably provided in the guide cavity, and the guide slider is slidably sleeved with the inclined ejector rod; the guide slider is also fixedly connected to a straight push rod; the straight push rod is fixedly connected to the one-stage push plate; the intersection of the clearance cavity and the guide cavity forms a thrust structure for limiting the travel of the guide slider. In this way, the present invention provides a guide slider slidably sleeved with the inclined ejector rod in the guide cavity, which can move synchronously during the first stage of demoulding, shortening the length of the inclined ejector rod and reducing the risk of bending due to excessive force.

Description

Technical Field

[0001] The invention belongs to the technical field of molds, and in particular relates to a two-stage ejection and demoulding device. Background Art

[0002] After the mold is opened during injection molding, the workpiece usually retreats along with the movable mold. The ejector mechanism on the movable mold then moves along the mold opening direction to eject the workpiece and separate it from the movable mold. The workpiece is then taken out manually or by a robot.

[0003] When an injection molded product features lateral features such as holes or slots that are angled with the parting direction, a corresponding movable block is required in the mold. After molding, this movable block can independently move and separate from the product to avoid interference with demolding.

[0004] Most existing movable blocks are ejected using a diagonal rod in conjunction with a guide block, such as the structure disclosed in Chinese Patent CN 114734587 A. During the ejection process, the diagonal rod is subjected to a reaction force parallel to the mold opening direction, resulting in a torsional torque with the guide block as the fulcrum. This poses a risk of bending when the diagonal rod is long or subjected to high forces.

[0005] In summary, the existing technology has obvious inconveniences and defects in actual use, so it is necessary to improve it. Summary of the Invention

[0006] The technical problem solved by the present invention is to shorten the length of the inclined ejector rod, effectively reduce the torsional moment thereof, and avoid bending due to excessive force.

[0007] In order to solve the above problems, the present invention provides a two-stage ejection demoulding device, comprising a two-stage push plate and a one-stage push plate sandwiched between a movable mold and a movable platen; the two-stage push plate and the one-stage push plate can move back and forth between the movable mold and the movable platen;

[0008] A first-level ejector block is movably embedded in one side of the movable mold; the first-level ejector block is connected to a first-level ejector rod; the first-level ejector rod movably passes through the movable mold and the second-level push plate, and its end is fixed to the first-level push plate;

[0009] A secondary ejector block is movably embedded on the primary ejector block; the secondary ejector block is connected to an inclined ejector rod; the inclined ejector rod movably passes through the primary ejector block and the movable mold, and its end portion is slidably arranged on the secondary push plate;

[0010] The movable mold is provided with a yield cavity and a guide cavity for the inclined ejector rod to pass through and which are interconnected; a guide slider is slidably provided in the guide cavity, and the guide slider is slidably sleeved with the inclined ejector rod; the guide slider is also fixedly connected to the straight push rod; the straight push rod movably passes through the secondary push plate and its end is fixedly connected to the primary push plate; the intersection position of the yield cavity and the guide cavity forms a thrust structure for limiting the travel of the guide slider.

[0011] According to the two-stage ejection demoulding device of the present invention, the angle between the inclined ejector and the mold opening direction does not exceed 12°.

[0012] According to the two-stage ejection demoulding device of the present invention, the relief cavity and the guide cavity are staggered to form the thrust structure.

[0013] According to the secondary ejection and demoulding device of the present invention, two parallel groove plate members are fixed on the secondary push plate; a rail groove is provided in the groove plate member, and a hinge slider is slidably provided in the rail groove; an inclined rod push block is sandwiched between the two hinge sliders; and the inclined rod push block is fixedly connected to the inclined ejector rod.

[0014] According to the two-stage ejection demoulding device of the present invention, the inclined rod push block is rotatably clamped between the two hinged sliders.

[0015] According to the two-stage ejection and demoulding device of the present invention, the inclined ejector rod is a solid rod.

[0016] According to the two-stage ejection and demoulding device of the present invention, a limiting slide bar for slidingly cooperating with the inner wall of the guide cavity is fixed on the outer wall of the guide slide block.

[0017] According to the two-stage ejection demoulding device of the present invention, a guide hole is provided in the guide slider for slidingly sleeved with the inclined ejector rod; guide balls are evenly embedded on the inner wall of the guide hole; and the guide balls roll and abut against the outer wall of the inclined ejector rod.

[0018] In summary, the present invention provides a guide slider in the guide cavity that is slidably connected to the inclined ejector rod, which can move synchronously in the first-level demolding stage, shortening the length of the inclined ejector rod and reducing the risk of bending due to excessive force. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Figure 1 It is a structural schematic diagram of the present invention;

[0020] Figure 2 yes Figure 1 Front cross-sectional view of

[0021] Figure 3 yes Figure 2 - a schematic diagram of the structure in working state;

[0022] Figure 4 yes Figure 3 Schematic diagram of the structure of area B in the middle;

[0023] Figure 5 yes Figure 1 Schematic diagram of the structure of area A;

[0024] Figure 6 yes Figure 3 Schematic diagram of the structure of the middle C area;

[0025] Figure 7 yes Figure 6 Schematic diagram of the structure in the middle DD direction;

[0026] In the figure: 1- inclined ejector rod, 11- straight push rod, 12- guide slider, 13- secondary ejector block, 14- limit slide, 15- guide ball; 2- movable mold, 21- movable mold plate, 22- secondary push plate, 23- primary push plate, 24- yield cavity, 25- guide cavity; 3- primary ejector block, 4- slot plate, 41- hinged slider, 42- inclined rod push block; 100- workpiece. DETAILED DESCRIPTION

[0027] See also Figure 1 The present invention provides a two-stage ejection demoulding device, comprising a two-stage push plate 22 and a one-stage push plate 23 sandwiched between a movable mold 2 and a movable plate 21; the two-stage push plate 22 and the one-stage push plate 23 can reciprocate between the movable mold 2 and the movable plate 21;

[0028] The movable mold 2 is installed on the movable mold plate 21. The connection relationship between the two is not shown in the figure. Those skilled in the art can know the connection method between the two based on the known structure.

[0029] A first-level ejector block 3 is movably embedded in one side of the movable mold 2; the first-level ejector block 3 is connected to a first-level ejector rod (not shown in the figure); the first-level ejector rod movably passes through the movable mold 2 and the second-level ejector plate 22, and its end is fixed to the first-level ejector plate 23;

[0030] See also Figure 2 The primary ejector block 3 is movably embedded with a secondary ejector block 13; the secondary ejector block 13 is connected to the inclined ejector rod 1; the inclined ejector rod 1 movably passes through the primary ejector block 3 and the movable mold 2, and its end portion is slidably arranged on the secondary push plate 22;

[0031] The movable mold 2 is provided with a clearance cavity 24 and a guide cavity 25 for the inclined ejector rod 1 to pass through and which are interconnected; a guide slider 12 is slidably provided in the guide cavity 25, and the guide slider 12 is slidably sleeved with the inclined ejector rod 1; the guide slider 12 is also fixedly connected to the straight push rod 11; the straight push rod 11 is movably connected to the secondary push plate 22 and its end is fixedly connected to the primary push plate 23; the intersection of the clearance cavity 24 and the guide cavity 25 forms a thrust structure for limiting the travel of the guide slider 12;

[0032] When the mold is opened after injection molding, the movable mold 2, the movable platen 21, the secondary push plate 22 and the primary push plate 23 retreat synchronously, and the workpiece 100 is attached to the primary top block 3.

[0033] Combine Figure 3, then the movable mold 2 and the movable platen 21 remain stationary, and the primary push plate 23 and the secondary push plate 22 move forward synchronously along the mold opening direction until the guide slider 12 abuts against the thrust structure; at this time, the primary ejector block 3 and the secondary ejector block 13 move forward together, and the workpiece 100 is separated from the movable mold 2;

[0034] More preferably, the thrust structure of the present invention is formed by staggered arrangement of the clearance cavity 24 and the guide cavity 25; the central axes of the clearance cavity 24 and the guide cavity 25 do not overlap. During the production stage, the clearance cavity 24 and the guide cavity 25 are machined on both sides of the movable mold 2. After the two cavities are formed, the thrust structure is naturally formed at the intersection between them.

[0035] Those skilled in the art can set an oil cylinder on the movable platen 21 to drive the primary push plate 23 and the secondary push plate 22 to move forward.

[0036] Afterwards, the movable mold 2, the movable mold plate 21 and the first-level push plate 23 remain stationary, and the second-level push plate 22 continues to move forward; Figure 4 The inclined ejector rod 1 slides obliquely relative to the guide slider 12, pushing the secondary ejector block 13 obliquely to separate the workpiece 100 from the primary ejector block 3, and at the same time, it is also separated from the workpiece 100; then the workpiece 100 is taken away manually or by a robot.

[0037] During the pushing process, the inclined ejector rod 1 slides horizontally relative to the secondary push plate 22, so that the inclined ejector rod 1 maintains a constant tilt angle during the process of being pushed out obliquely.

[0038] To avoid excessive horizontal force, the angle between the inclined ejector rod 1 and the mold opening direction (i.e., the aforementioned inclination angle) does not exceed 12°. The stroke of the secondary push plate 22 is inversely proportional to this angle, and those skilled in the art can adaptably set the values ​​of the two.

[0039] The guide slider 12 of the present invention can move synchronously in the primary demoulding stage, shortening the length of the inclined ejector rod 1; the distances between both ends of the inclined ejector rod 1 and the guide slider 12 are within an appropriate range, reducing the risk of bending due to excessive force.

[0040] See also Figure 5 As an embodiment, two parallel groove plates 4 are fixed on the secondary push plate 22; a rail groove is provided in the groove plate 4, and a hinge slider 41 is slidably provided in the rail groove; an inclined rod push block 42 is sandwiched between the two hinge sliders 41; the inclined rod push block 42 is fixedly connected to the inclined push rod 1;

[0041] When the secondary push plate 22 advances or retreats, the inclined push rod 1 drives the inclined rod push block 42 and the hinge slider 41 to slide in the rail groove to keep the inclination angle unchanged.

[0042] Better yet, the inclined rod push block 42 is rotatably clamped between the two hinge sliders 41. During installation, the inclination angle of the inclined push rod 1 can be adjusted to meet preset requirements.

[0043] In order to ensure sufficient strength, the inclined ejector rod 1 of the present invention is a solid rod.

[0044] See also Figure 6 As an embodiment, a limiting slide bar 14 is fixed on the outer wall of the guide slider 12 for sliding cooperation with the inner wall of the guide cavity 25; the limiting slide bar 14 is preferably formed of a wear-resistant material, which effectively reduces the contact area between the guide slider 12 and the inner wall of the guide cavity 25, while increasing the service life and reducing the frequency of maintenance.

[0045] See also Figure 7 Furthermore, the guide slider 12 is provided with a guide hole for slidingly engaging the lift rod 1; guide balls 15 are evenly embedded in the inner wall of the guide hole; the guide balls 15 roll against the outer wall of the lift rod 1; the guide balls 15 limit the axial sliding of the lift rod 1 along the guide hole, effectively reducing friction during sliding, greatly reducing ejection resistance, and significantly reducing the risk of bending of the lift rod 1. Under the same ejection load, the diameter of the lift rod 1 can be effectively reduced, or a hollow rod can be used, saving manufacturing materials and reducing the weight of the lift rod 1.

[0046] In summary, the present invention provides a two-stage ejection and demolding device, which can move synchronously in the first-stage demolding stage by arranging a guide slider that is slidably connected to the inclined ejector rod in the guide cavity, thereby shortening the length of the inclined ejector rod and reducing the risk of bending due to excessive force.

[0047] Of course, the present invention may have many other embodiments. Without departing from the spirit and essence of the present invention, those skilled in the art may make various corresponding changes and modifications based on the present invention, but these corresponding changes and modifications should all fall within the scope of protection of the claims attached to the present invention.

Claims

1. A two-stage ejection demoulding device, characterized in that: It includes a secondary push plate and a primary push plate sandwiched between the movable mold and the movable plate; the secondary push plate and the primary push plate can move back and forth between the movable mold and the movable plate; A first-level ejector block is movably embedded in one side of the movable mold; the first-level ejector block is connected to a first-level ejector rod; the first-level ejector rod movably passes through the movable mold and the second-level push plate, and its end is fixed to the first-level push plate; A secondary ejector block is movably embedded on the primary ejector block; the secondary ejector block is connected to an inclined ejector rod; the inclined ejector rod movably passes through the primary ejector block and the movable mold, and its end portion is slidably arranged on the secondary push plate; The movable mold is provided with a clearance cavity and a guide cavity for the inclined ejector rod to pass through and communicate with each other; a guide slider is slidably provided in the guide cavity, and the guide slider is slidably sleeved with the inclined ejector rod; the guide slider is also fixedly connected to the straight push rod; the straight push rod movably passes through the secondary push plate and its end is fixedly connected to the primary push plate; the intersection of the clearance cavity and the guide cavity forms a thrust structure for limiting the travel of the guide slider; The outer wall of the guide slider is fixed with a limit slide for slidingly cooperating with the inner wall of the guide cavity; the guide slider is provided with a guide hole for slidingly sleeved with the inclined push rod; guide balls are evenly embedded on the inner wall of the guide hole; the guide balls roll and abut against the outer wall of the inclined push rod.

2. The two-stage ejection demoulding device according to claim 1, characterized in that: The included angle between the inclined ejector and the mold opening direction does not exceed 12°.

3. The two-stage ejection demoulding device according to claim 1, characterized in that: The yield cavity and the guide cavity are staggered to form the thrust structure.

4. The two-stage ejection demoulding device according to any one of claims 1 to 3, characterized in that: Two parallel groove plates are fixed on the secondary push plate; a rail groove is provided in the groove plate, and a hinge slider is slidably provided in the rail groove; an inclined rod push block is sandwiched between the two hinge sliders; the inclined rod push block is fixedly connected to the inclined push rod.

5. The two-stage ejection demoulding device according to claim 4, characterized in that: The inclined rod push block is rotatably clamped between the two hinge sliders.

6. The two-stage ejection demoulding device according to claim 4, characterized in that: The inclined ejector rod is a solid rod.

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