Double-color injection mold

Abstract

The utility model relates to the field of injection molds, and provides a double-color injection mold which comprises an upper mold assembly and a lower mold assembly, the lower mold assembly and the upper mold assembly are oppositely arranged, and the lower mold assembly is provided with a forming assembly and a moving assembly. The forming assembly comprises a forming needle which abuts against the upper mold assembly forwards during first-time injection molding and moves backwards during second-time injection molding so as to form an inverted buckle hole position in the forming cavity, the moving assembly comprises a moving plate arranged on the lower mold assembly and a reset assembly controlling the moving plate to move relative to the forming cavity, and the forming needle is fixedly arranged on the moving plate. According to the double-color injection mold provided by the utility model, during first injection molding, the forming needle abuts against the upper mold assembly, during second injection molding, the forming needle moves backwards and retreats from the forming cavity, and a plastic material during second injection molding can fill the forming cavity and a hole position formed by abutting of the forming needle, so that the cross section of a colloid formed by second injection molding is of an inverted T-shaped inverted buckle structure; the bonding strength of the joint of different plastic materials is greatly improved, and mold stripping is simple.

Description

Technical Field

[0001] The utility model belongs to the field of injection molds, in particular to a double-color injection mold. Background Art

[0002] A two-color injection mold refers to two plastic materials (two different types of plastics, and can be clearly distinguished as different plastics on the product, which can be different colors, different hardness, etc.) injected on the same injection molding machine, molded in two times, usually composed of two sets of molds, but the product only needs to be ejected once, with high injection efficiency and high use efficiency. The appearance of the product molded by the two-color injection mold is more beautiful, and the assembly performance of the product will be better if it is directly injected and molded. The two-color injection mold can combine plastics of different colors or plastic materials of different materials and eject them at one time.

[0003] However, due to the difference in plastic materials, the strength of the joint between the two plastic materials may be insufficient. When subjected to external force, the softer glue will separate from the hard glue, thereby damaging the product. In the prior art, the strength of the joint is usually increased by reinforcing the joint with glue or adding fasteners after demolding. However, this method is not applicable to molded parts with complex structures, and adding fasteners may affect the use effect of the product. Alternatively, the prior art sets a "T"-shaped structure at the joint of the two plastic materials, but it cannot be demolded or is difficult to demold after molding. Utility Model Content

[0004] The utility model aims to overcome at least one of the deficiencies of the above-mentioned prior art and provides a two-color injection mold. The molding needle arranged on the movable plate moves forward to abut against the upper mold component during the first injection molding, and moves backward to completely exit the molding cavity during the second injection molding, forming an undercut hole in the molding cavity, thereby increasing the bonding force of the two plastic materials and making it easy to demold the injection molded product.

[0005] The technical solution of the utility model is: a two-color injection mold, including an upper mold component and a lower mold component, the lower mold component is arranged opposite to the upper mold component, the lower mold component is provided with a molding component and a moving component, the molding component includes a molding needle that presses forward against the upper mold component during the first injection and moves backward during the second injection to form an undercut hole in the molding cavity, the moving component includes a moving plate arranged on the lower mold component and a reset component that controls the movement of the moving plate relative to the molding cavity, and the molding needle is fixedly arranged on the moving plate.

[0006] Furthermore, the reset assembly includes an abutment member, one end of which can abut against the bottom of the movable plate, and the other end is provided with a reset rod for driving the abutment member. When the reset rod is actuated, the abutment member is driven to rotate, so that the abutment member abuts against the bottom of the movable plate and pushes the movable plate to move relative to the molding cavity.

[0007] Furthermore, the reset assembly is further provided with a fixed seat, the fixed seat is provided with a rotating shaft, and the abutment member is rotatably provided on the fixed seat via the rotating shaft.

[0008] Furthermore, the rotating shaft is arranged at a position 1 / 3 of the distance between the abutment and the reset rod. When the reset rod moves downward, the abutment rotates with the rotating shaft as the rotation center, so that one end of the abutment abuts against the bottom of the movable plate and pushes the movable plate to move relative to the molding cavity.

[0009] Furthermore, the reset assembly is further provided with a contact rod, and the contact rod is arranged at an end of the reset rod away from the abutment member.

[0010] Furthermore, the molding needle is fixed to the top of the movable plate away from the abutment member. During the first injection molding, the reset assembly pushes the movable plate to move relative to the molding cavity, so that the molding needle abuts against the upper mold assembly forward; during the second injection molding, the molding needle moves backward and completely exits the molding cavity to form an undercut structure in the molding cavity.

[0011] Furthermore, the forming needle can be provided as one or more.

[0012] Furthermore, the forming needle can be configured to be cylindrical or square.

[0013] Furthermore, the upper mold assembly includes a first mold group for the first injection molding and a second mold group for the second injection molding, the first mold group is provided with a molding column, and the end of the molding column coaxially abuts against the end of the molding needle.

[0014] Furthermore, the circumferential dimension of the molding column is smaller than the circumferential dimension of the molding needle.

[0015] By adopting the above technical scheme, the beneficial effects of the design of the utility model are as follows: the molding needle fixedly arranged on the movable plate moves forward to abut against the upper mold assembly during the first injection molding under the control of the reset assembly, and moves backward to completely exit the molding cavity during the second injection molding to form an undercut hole in the molding cavity. The plastic material of the second injection molding can fill the molding cavity and the hole reserved by the molding needle, so that the cross-section of the colloid molded by the second injection molding presents an inverted "T"-shaped undercut structure. The undercut structure can greatly increase the strength of the joints of different plastic materials. Moreover, since the molding needle has completely exited the molding cavity before the second injection molding, the ejection mechanism can be directly used to eject the molded part after the injection molding is completed, and demolding is simple. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the drawings required for use in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without creative work.

[0017] Figure 1 This is a three-dimensional assembly diagram of a two-color injection mold provided by an embodiment of the utility model

[0018] Figure 2 yes Figure 1 A schematic three-dimensional diagram of the structure of the middle part components and injection molded parts;

[0019] Figure 3 yes Figure 2 Schematic diagram of the state of the reset assembly when the molding needle at A in the middle moves forward and hits the upper mold assembly;

[0020] Figure 4 yes Figure 2 Schematic diagram of the state of the assembly being reset after the molding needle at B moves backward and exits the upper mold assembly;

[0021] Figure 5 It is a schematic cross-sectional view of the joint of the injection molded part provided by the embodiment of the utility model;

[0022] Figure 6 This is a schematic diagram of the position relationship between the molding needle and the upper mold assembly when the two-color injection mold provided by the embodiment of the utility model completes the first injection;

[0023] Figure 7 It is a schematic diagram of the position relationship between the molding needle and the upper mold component when the two-color injection mold provided by the embodiment of the utility model completes the second injection.

[0024] The reference numerals and names in the figures are as follows:

[0025] Rotating table 1, upper mold assembly 2, molding column 21, lower mold assembly 3, molding cavity 4, molding part 5, reset rod 6, touch rod 61, abutment part 7, abutment surface 71, fixed seat 8, rotating shaft 81, moving plate 9, molding needle 10, plastic material 1 11, plastic material 2 12 DETAILED DESCRIPTION

[0026] In order to make the purpose, technical solution and advantages of the utility model more clear, the utility model is further described in detail below in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described here are only used to explain the utility model and are not used to limit the utility model.

[0027] It should be noted that the terms “setting” and “connection” should be understood in a broad sense. For example, it can be directly setting or connecting, or it can be indirectly setting or connecting through a central component or a central structure.

[0028] In addition, if there are terms such as "longitudinal", "lateral", "length", "width", "thickness", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside" and the like indicating orientation or positional relationship in the embodiments of the present invention, they are based on the orientation or positional relationship or the conventional placement state or use state shown in the drawings, and are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the structure, feature, device or element referred to must have a specific orientation or positional relationship, nor must it be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the present invention. In the description of the present invention, unless otherwise specified, "multiple" means two or more.

[0029] The various specific technical features and embodiments described in the specific implementation methods can be combined in any suitable manner unless there is any contradiction. For example, different implementation methods can be formed by combining different specific technical features / embodiments. In order to avoid unnecessary repetition, the various possible combinations of the specific technical features / embodiments in the present utility model will not be described separately.

[0030] refer to Figure 1 and Figure 2As shown, an embodiment of the utility model provides a two-color injection mold, including an upper mold assembly 2 and a lower mold assembly 3. The lower mold assembly 3 and the upper mold assembly 2 are arranged relative to each other. The lower mold assembly 3 is provided with a molding assembly and a moving assembly. The molding assembly includes a molding needle 10 which presses forward against the upper mold assembly 2 during the first injection and moves backward during the second injection to form an undercut hole in the molding cavity 4. The moving assembly includes a moving plate 9 arranged on the lower mold assembly 3 and a reset assembly for controlling the movement of the moving plate 9 relative to the molding cavity 4. The molding needle 10 is fixedly arranged on the moving plate 9. In the embodiment of the utility model, the molding needle 10 and the movable plate 9 are fixedly arranged, and the reset component can control the movable plate 9 to move forward and backward relative to the upper mold component 2, thereby driving the molding needle 10 to move forward and press against the upper mold component 2 during the first injection molding. After the first injection molding is completed, the movable plate 9 drives the molding needle 10 to move backward and completely withdraw from the molding cavity 4. Due to the arrangement of the molding needle 10 during the first injection molding, after the first injection molding is completed, the first injection molded part forms an undercut hole. During the second injection molding, the plastic material can completely fill the molding cavity 4 and the hole reserved by the molding needle 10, so that after the second injection molding is completed, the cross-section of the second injected colloid presents an inverted "T"-shaped undercut structure at the hole. The undercut structure can greatly increase the strength of the joints of different plastic materials, and since the molding needle 10 has completely withdrawn from the molding cavity 4 before the second injection molding, the ejection mechanism can be directly used to eject the molded part 5 after the second injection molding is completed. It can be directly ejected without other operations, and demolding is simple.

[0031] refer to Figure 1-7 As shown, the embodiment of the utility model can increase the bonding strength between two different plastic materials without increasing the difficulty of demolding, and the "car interior support cup" is used as an example for description. The injection molding machine is provided with a rotating table 1, and a lower mold assembly 3 is provided at the upper end of the rotating table 1. The lower mold assembly 3 is relatively provided with an upper mold assembly 2, and the upper mold assembly 2 can be provided with two groups, which are respectively used for the first injection and the second injection. The lower mold assembly 3 is provided with a moving assembly, and the moving assembly includes a moving plate 9 and a reset assembly for controlling the moving plate 9 to move relative to the molding cavity 4. The reset assembly includes an abutment 7, and an abutment surface 71 is provided at one end of the abutment 7, and the abutment surface 71 can abut the bottom of the moving plate 9. The other end of the abutment 7 is provided with a reset rod 6 for driving the abutment 7 to rotate. When the reset rod 6 is actuated, the reset rod 6 drives the abutment 7 to rotate, so that the abutment surface 71 of the abutment 7 abuts the moving plate 9, and the moving plate 9 is pushed to move relative to the molding cavity 4 under the continuous action of the reset rod 6, thereby driving the molding needle 10 to move forward and abut against the upper mold assembly 2. After the second injection molding, the molding needle 10 can move forward to eject the finished injection molded product, that is, the molding needle 10 can also serve as an ejection mechanism or as a part of the ejection mechanism.

[0032] Specifically, the reset assembly is also provided with a fixed seat 8, which is fixedly arranged on the lower mold assembly 3. A rotating shaft 81 is arranged on the fixed seat 8, and the abutment 7 is rotatably arranged on the fixed seat 8 through the rotating shaft 81. Preferably, a rotating shaft hole is arranged at one end of the abutment 7 which is 1 / 3 away from the reset rod, and the rotating shaft 81 passes through the rotating shaft hole to rotatably arrange the abutment 7 on the fixed seat 8, so that when the reset rod 6 moves, the abutment 7 rotates with the rotating shaft 81 as the rotation center, so that the abutment surface 71 abuts against the movable plate 9 and pushes the movable plate 9 to move relative to the molding cavity 4.

[0033] Specifically, a touch rod 61 is provided at one end of the reset rod 6 away from the abutment 7, and the touch rod 61 can apply a force to the reset rod 6. The action process in this embodiment is as follows: during the first injection molding, the clamping force of the first set of injection molds will be transmitted to the touch rod 61, and the touch rod 61 will apply the received clamping force to the reset rod 6, so that the reset rod 6 moves backward relative to the upper mold assembly 2, driving the abutment 7 to rotate with the rotating shaft 81 as the rotation center, and the abutment surface 71 of the abutment 7 abuts the bottom of the movable plate 9, and under the continuous push of the reset rod 6, the movable plate 9 moves forward relative to the molding cavity 4, thereby driving the molding needle 10 to move forward and abut against the upper mold assembly 2; during the second injection molding, the second set of injection molds is provided with an avoidance position of the touch rod 61, so the clamping force of the second set of injection molds will not be transmitted to the touch rod 61, and a reset spring is provided inside the reset member. Since no force is applied to the reset member, the reset member will move forward relative to the upper mold assembly 2. , the abutment member 7 rotates with the rotating shaft 81 as the rotation center, and the abutment surface 71 of the abutment member 7 leaves the bottom of the movable plate 9. Under the combined action of the clamping force of the second set of injection molds and the gravity of the movable plate 9, the movable plate 9 moves backward relative to the molding cavity 4, thereby driving the molding needle 10 to move backward until it completely exits the molding cavity 4; such a structural design can make the injection molded part after the first injection molding is completed. Due to the existence of the molding needle 10, the injection molded part has holes that have not been injected. During the second injection molding, since the molding needle 10 completely exits the molding cavity 4, the injected plastic material 12 will fill the molding cavity 4 and the above-mentioned holes that have not been injected. The cross-section of the injected colloid after the second injection molding is completed presents an inverted "T"-shaped buckle structure, which can increase the strength of the joint between different plastic materials. In order to achieve better results, generally, the plastic material with higher hardness is injection molded first, and then the plastic material with softer hardness is injection molded. After the injection molding is completed, the schematic diagram of the cross-section of the joint of the injection-molded part is as shown in the figure Figure 5 As shown, due to the presence of the molding needle 10, there are undercut holes that are not molded after the plastic material 11 is injected, and the plastic material 2 12 fills the undercut holes after injection, and the plastic material 2 12 forms an inverted "T"-shaped undercut structure.

[0034] In a specific application, the upper mold assembly 2 is provided with two groups, which are respectively used for the first injection molding (molding the hard glue on the outside) and the second injection molding (molding the soft glue on the inside). The front end of the molding needle 10 can be a flat-headed cylindrical shape. During the first injection molding process, the end of the molding column 21 in the upper mold assembly 2 coaxially presses against the front end of the molding needle 10, and the diameter of the molding column 21 is smaller than the diameter of the molding needle 10. During the second injection molding process, the upper mold assembly 2 has no corresponding molding column 21, so a through inverted "T"-shaped hole (undercut structure) can be formed in the product of the first injection molding, and the material of the second injection molding enters the inverted "T"-shaped hole (undercut structure).

[0035] Specifically, the number of molding needles 10 can be set according to the actual molded part 5. For a molded part 5 with a simple structure and a small volume, one or a small number of molding needles 10 can be set. For a molded part 5 with a more complex structure and a larger volume, the molding needles 10 can be set at positions of the molded part 5 with greater force, or multiple molding needles 10 can be evenly set. There is no specific restriction on the shape of the molding needles 10, and it can be set to a cylindrical, square, etc., as long as it can form an undercut hole that has not been injected after the first injection molding.

[0036] The double-color injection mold provided by the utility model has a molding needle 10 fixedly arranged on the movable plate 9. Under the control of the reset component, during the first injection, the molding needle 10 moves forward to abut against the upper mold component 2, and during the second injection, the molding needle 10 moves backward to completely exit the molding cavity 4 to form an undercut hole in the molding cavity 4. The second plastic material 12 injected can fill the molding cavity 4 and the hole reserved by the molding needle 10, so that the cross-section of the colloid molded by the second injection presents an inverted "T"-shaped undercut structure. The undercut structure can greatly increase the bonding strength of different plastic materials (plastic material 1 11, plastic material 2 12), and because the molding needle 10 has completely exited the molding cavity 4 before the second injection, the ejection mechanism can be directly used to eject the molded part 5 after the injection is completed, and demolding is simple.

[0037] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modification, equivalent substitution or improvement made within the spirit and principle of the present invention shall be included in the protection scope of the present invention.

Claims

1. A two-color injection mold, comprising an upper mold assembly and a lower mold assembly, wherein the lower mold assembly is arranged opposite to the upper mold assembly, and characterized in that: The lower mold assembly is provided with a molding assembly and a moving assembly. The molding assembly includes a molding needle that presses forward against the upper mold assembly during the first injection and moves backward during the second injection to form an undercut hole in the molding cavity. The moving assembly includes a moving plate arranged on the lower mold assembly and a reset assembly that controls the movement of the moving plate relative to the molding cavity. The molding needle is fixedly arranged on the moving plate.

2. A two-color injection mold according to claim 1, characterized in that: The reset assembly includes an abutment member, one end of which can abut against the bottom of the movable plate, and the other end is provided with a reset rod for driving the abutment member. When the reset rod is actuated, the abutment member is driven to rotate, so that the abutment member abuts against the bottom of the movable plate and pushes the movable plate to move relative to the molding cavity.

3. A two-color injection mold as claimed in claim 2, characterized in that: The reset assembly is further provided with a fixing seat, the fixing seat is provided with a rotating shaft, and the abutment member is rotatably arranged on the fixing seat via the rotating shaft.

4. A two-color injection mold as claimed in claim 3, characterized in that: The rotating shaft is arranged at a position where the abutment is 1 / 3 away from the reset rod. When the reset rod moves downward, the abutment rotates with the rotating shaft as the rotation center, so that one end of the abutment abuts against the bottom of the movable plate and pushes the movable plate to move relative to the molding cavity.

5. A two-color injection mold as claimed in claim 4, characterized in that: The reset assembly is further provided with a bumper rod, and the bumper rod is arranged at one end of the reset rod away from the abutment member.

6. A two-color injection mold as claimed in claim 2, characterized in that: The molding needle is fixed to the top of the movable plate away from the abutment. During the first injection molding, the reset assembly pushes the movable plate to move relative to the molding cavity, so that the molding needle abuts against the upper mold assembly forward; during the second injection molding, the molding needle moves backward and completely exits the molding cavity to form an undercut structure in the molding cavity.

7. A two-color injection mold according to claim 6, characterized in that: The forming needles are arranged in one or more numbers.

8. A two-color injection mold according to claim 6, characterized in that: The forming needle is configured to be cylindrical or square.

9. A two-color injection mold according to claim 1, characterized in that: The upper mold assembly includes a first mold group for the first injection molding and a second mold group for the second injection molding. The first mold group is provided with a molding column, and the end of the molding column coaxially abuts against the end of the molding needle.

10. A two-color injection mold according to claim 9, characterized in that: The circumferential dimension of the forming column is smaller than the circumferential dimension of the forming needle.

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