One-piece injection molding device and method for lip glaze brush head

Abstract

The invention discloses an integrated injection molding device and method for a lip glaze brush head, comprising an injection molding machine frame, a die assembly and a rotating punch assembly; the die assembly comprises a die ring, a die forming unit is provided on the die ring, the die forming unit comprises a first die cavity and a second die cavity spaced apart on the die ring; the rotating punch assembly comprises a rotating frame, a punch unit is provided on the rotating frame; the punch unit comprises a first mold core and a second mold core rotatably sleeved on the lower end of the outer peripheral wall of the first mold core, the second mold core is provided with an external thread structure, and the first mold core is provided with a rod forming cavity; the invention completes the injection molding of the lip glaze brush head by first molding a first intermediate, coating one end of the outer peripheral wall of the first intermediate with a heat-shrinkable color film to form a color gradient effect, and then secondary molding a second intermediate coating one end of the first intermediate and the heat-shrinkable color film, thereby avoiding the use of a two-color injection molding process, improving production efficiency and reducing production costs.

Description

Technical Field

[0001] The present invention relates to the technical field of injection molding, and in particular to an integrated injection molding device and method for a lip glaze brush head. Background Art

[0002] The lip gloss brush head is an appearance part with high decorative requirements. In order to present a color gradient visual effect, it is often necessary to use a two-color injection molding process for molding.

[0003] Two-color injection molding equipment is a molding process equipment that injects two different materials into one product, which can achieve different colors and touch appearance effects. This process equipment is usually completed by a set of molds and requires a special two-color injection molding machine. The working principle of the two-color injection molding machine is to inject two different colors of plastic into the same mold, molding in two times, but the product is only ejected once.

[0004] Although this process equipment can improve the aesthetics and practicality of the product, it requires a dedicated two-color injection mold and a two-color injection molding machine for molding, resulting in higher production costs and lower production efficiency for the lip glaze brush heads, which is not conducive to the large-scale production of lip glaze brush heads. Summary of the invention

[0005] The purpose of the present invention is to overcome the above-mentioned shortcomings and provide an integrated injection molding device and method for a lip glaze brush head, thereby avoiding the use of a two-color injection molding process, which is beneficial to improving production efficiency and reducing production costs.

[0006] To achieve the above object, the specific scheme of the present invention is as follows:

[0007] A first aspect of the present invention provides an integrated injection molding device for a lip glaze brush head, comprising an injection molding frame, on which a concave mold assembly and a rotating convex mold assembly arranged above the concave mold assembly are arranged;

[0008] The die assembly comprises a die ring, a die forming unit is arranged on the die ring, and the die forming unit comprises a first die cavity and a second die cavity which are arranged on the die ring at intervals;

[0009] The rotary punch assembly comprises a rotating frame on which a punch unit is arranged; the punch unit comprises a first mold core and a second mold core rotatably sleeved on the lower end of the outer peripheral wall of the first mold core, the second mold core is provided with an external thread structure, and the first mold core is provided with a rod forming cavity.

[0010] The present invention further comprises that when the second mold core is inserted into the first mold cavity, the first mold core, the second mold core, the first mold cavity and the rod molding cavity together form the first molding cavity; when the second mold core is inserted into the second mold cavity, the second mold core, the first intermediate body and the second mold cavity together form the second molding cavity.

[0011] The present invention further provides that the die ring is provided with a film feeding assembly between the first die cavity and the second die cavity;

[0012] The film feeding assembly includes a feeder, a feeding cavity arranged on a die ring, and a heating tube arranged on the inner wall of the feeding cavity; tear lines for breaking the heat-shrinkable color film are arranged at equal intervals on the heat-shrinkable color film; when the first intermediate is inserted into the heating tube, the feeder transports the heat-shrinkable color film to between the periphery of the first intermediate and the heating tube, and the heating tube heats the heat-shrinkable color film so that the heat-shrinkable color film shrinks and wraps around the outer peripheral wall of the first intermediate.

[0013] The present invention further comprises a push rod disposed on the top of the injection molding frame, and an output end of the push rod is rotatably connected to the rotating frame; the rotating frame comprises a driving shaft, and a plurality of driving grooves connected end to end in the circumferential direction are disposed on the outer wall of the driving shaft; the injection molding frame is elastically and floatingly connected to a driving pin, and the driving pin is movably embedded in the driving groove, and the rotating frame can be driven to rotate by the driving pin and the driving groove cooperating with each other;

[0014] A plurality of groups of concave die forming units are arranged on the concave die ring along the circumferential direction; and a plurality of groups of convex die units are arranged on the rotating frame.

[0015] In the present invention, each group of driving grooves includes a first vertical groove, a second vertical groove and a third vertical groove which are arranged side by side at intervals and whose depths gradually increase; the height of the lower end of the first vertical groove, the height of the lower end of the second vertical groove and the height of the lower end of the third vertical groove decrease in sequence;

[0016] A first spiral groove is connected between the lower end of the first vertical groove and the lower end of the second vertical groove, a second spiral groove is connected between the lower end of the second vertical groove and the lower end of the third vertical groove, a third spiral groove is connected between the lower end of the third vertical groove and the lower end of the first vertical groove of the adjacent driving groove, a depth of one end of the third spiral groove is greater than the depth of the third vertical groove, a depth of the other end of the third spiral groove is less than the depth of the first vertical groove, and both ends of the third spiral groove are smoothly transitioned.

[0017] The present invention further comprises: when the drive pin is located in the first vertical groove, the second mold core is located directly above the first die cavity; when the drive pin is located in the second vertical groove, the second mold core is located directly above the feeding cavity; when the drive pin is located in the third vertical groove, the second mold core is located directly above the second die cavity.

[0018] The present invention further provides a feed trough between adjacent die forming units of the die ring, a friction plate is provided above the feed trough on the injection molding machine frame, and a friction wheel is provided on the outer wall of the second mold core. When the friction wheel is in friction contact with the friction plate, the friction wheel drives the second mold core to rotate.

[0019] The present invention further provides an injection molding frame with a center hole coaxially arranged with the die ring, the drive shaft movably passes through the center hole, and a return spring is connected between the drive shaft and the injection molding frame along the axial direction of the drive shaft.

[0020] Furthermore, in the present invention, a first glue injection nozzle is arranged at a position of the injection molding machine frame corresponding to the first molding cavity, and a second glue injection nozzle is arranged at a position corresponding to the second molding cavity.

[0021] A second aspect of the present invention provides an integrated injection molding method for a lip glaze brush head, comprising the integrated injection molding device described above, the method comprising the following steps:

[0022] Step S1: injection molding a first intermediate in a first molding cavity;

[0023] Step S2: coating one end of the peripheral wall of the first intermediate body with a heat shrinkable color film;

[0024] Step S3: injection molding a second intermediate body covering the lower end of the first intermediate body and the heat shrinkable color film in the second molding cavity, and molding an internal thread structure at the upper end of the inner wall of the second intermediate body.

[0025] The beneficial effects of the present invention are as follows: the present invention first forms a first intermediate, then covers one end of the outer peripheral wall of the first intermediate with a heat-shrinkable color film to form a color gradient effect, and then secondary forms a second intermediate covering one end of the first intermediate and the heat-shrinkable color film to complete the injection-molded lip glaze brush head, thereby avoiding the use of a two-color injection molding process, which is beneficial to improving production efficiency and reducing production costs. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] Figure 1 It is a structural schematic diagram of the integrated injection molding device of the present invention;

[0027] Figure 2 is a cross-sectional schematic diagram of the integrated injection molding device of the present invention;

[0028] Figure 3 It is a cross-sectional schematic diagram of the integrated injection molding device of the present invention when the second mold core is inserted into the first concave mold cavity;

[0029] Figure 4 yes Figure 3 A local enlarged schematic diagram of the middle A;

[0030] Figure 5 It is a cross-sectional schematic diagram of the one-piece injection molding device of the present invention when the second mold core is inserted into the heating tube;

[0031] Figure 6 yes Figure 5 A partial enlarged schematic diagram of point B in the middle;

[0032] Figure 7It is a cross-sectional schematic diagram of the one-piece injection molding device of the present invention when the second mold core is inserted into the second concave mold cavity;

[0033] Figure 8 yes Figure 7 A partial enlarged schematic diagram of point C in the middle;

[0034] Fig. 9 It is a structural schematic diagram of the concave mold assembly of the present invention;

[0035] Fig.10 is a cross-sectional schematic diagram of a concave mold assembly of the present invention;

[0036] Fig.11 It is a structural schematic diagram of the die ring of the present invention;

[0037] Fig.12 It is a structural schematic diagram of the rotary punch assembly of the present invention;

[0038] Fig.13 yes Fig.12 A partial enlarged schematic diagram of point D in the middle;

[0039] Fig.14 is a cross-sectional schematic diagram of the rotary punch assembly of the present invention;

[0040] Fig.15 It is a cross-sectional schematic diagram of the male mold unit of the present invention;

[0041] Fig.16 It is a cross-sectional schematic diagram of the cooperation of the driving pin, the injection molding machine frame and the rotating frame of the present invention;

[0042] Fig.17 is a cross-sectional schematic diagram of a lip glaze brush head after injection molding of the present invention;

[0043] Fig.18 It is a schematic flow chart of the one-piece injection molding method of the present invention;

[0044] Explanation of the reference numerals: 1. injection molding frame; 21. die ring; 211. first die cavity; 212. second die cavity; 213. feeding cavity; 22. feeder; 23. heating tube; 24. discharge chute; 31. rotating frame; 311. driving shaft; 3121. first vertical groove; 3122. second vertical groove; 3123. third vertical groove; 3124. first spiral groove; 3125. second spiral groove; 3126. third spiral groove; 32. first mold core; 321. rod forming cavity; 33. second mold core; 331. external thread structure; 34. friction wheel; 4. push rod; 5. driving pin; 6. friction plate; 7. return spring; 8. first glue injection nozzle; 9. second glue injection nozzle; 101. first intermediate; 102. second intermediate; 103. heat shrinkable color film; 104. internal thread structure. DETAILED DESCRIPTION

[0045] The present invention will be further described in detail below in conjunction with the accompanying drawings and specific embodiments, but the implementation scope of the present invention is not limited thereto.

[0046] The lip gloss brush head of this embodiment includes a first intermediate body 101, a second intermediate body 102 sleeved on one end of the first intermediate body 101, and a heat shrinkable color film 103 arranged between the first intermediate body 101 and the second intermediate body 102. The heat shrinkable color film 103 is made of PVC or PET material, and a decorative pattern layer or color layer is sprayed, printed or electroplated on the PVC or PET material, so that the lip gloss brush head presents different appearance effects, such as a color gradient effect, through the heat shrinkable color film 103.

[0047] like Figures 1 to 17 As shown, the one-piece injection molding device of a lip glaze brush head described in this embodiment includes an injection molding frame 1, on which a concave mold assembly and a rotating convex mold assembly arranged above the concave mold assembly are arranged;

[0048] The die assembly includes a die ring 21, on which a die forming unit is arranged, and the die forming unit includes a first die cavity 211 and a second die cavity 212 which are arranged at intervals on the die ring 21; the rotating punch assembly includes a rotating frame 31, on which a punch unit is arranged; the punch unit includes a first mold core 32 and a second mold core 33 which is rotatably sleeved on the lower end of the outer peripheral wall of the first mold core 32, the second mold core 33 is provided with an external thread structure 331, and the first mold core 32 is provided with a rod forming cavity 321 to form the rod portion of the first intermediate 101.

[0049] The integrated injection molding equipment described in this embodiment, specifically, when the second mold core 33 is inserted into the first mold cavity 211, the first mold core 32, the second mold core 33, the first mold cavity 211 and the rod molding cavity 321 jointly form the first molding cavity; when the second mold core 33 is inserted into the second mold cavity 212, the second mold core 33, the first intermediate body 101 and the second mold cavity 212 jointly form the second molding cavity.

[0050] During the molding process, the male mold unit is first driven by the rotating frame 31 to move to a position corresponding to the female mold unit, and the male mold unit is molded with the female mold unit, so that the second mold core 33 is inserted into the first female mold cavity 211, so that the first mold core 32, the second mold core 33, the first female mold cavity 211 and the rod molding cavity 321 form a first molding cavity, and then a molten transparent plastic (such as polyethylene, polypropylene, methyl methacrylate) is injected into the first molding cavity to form a first intermediate 101. After holding the pressure for 20 seconds, the rotating frame 31 drives the male mold unit and the molding unit to demold. Due to the adhesive force between the first intermediate 101 and the second mold core 33, the molded first intermediate 101 moves out of the first female mold cavity 211 along with the second mold core 33;

[0051] Then, the heat shrinkable color film 103 is coated on one end of the first intermediate 101. After completion, the rotating frame 31 drives the male mold unit and the molded first intermediate 101 and the heat shrinkable color film 103 to move to the position corresponding to the second female mold cavity 212, and the second mold core 33, the first intermediate 101, and the heat shrinkable color film 103 are inserted into the second female mold cavity 212. At this time, the second mold core 33, the first intermediate 101 and the second female mold cavity 212 form a second molding cavity, and then a molten transparent plastic (such as polyethylene, polypropylene, methyl methacrylate) is injected into the second molding cavity to form the second intermediate 102, and the second intermediate 102 is combined with the first intermediate 101 as a whole. An external thread structure 331 is arranged, so that an internal thread structure 104 is synchronously formed on the inner wall of the second intermediate body 102. After holding the pressure for 25 seconds, the rotating frame 31 drives the male mold unit and the molding unit to demould, and the molded second intermediate body 102 and the second mold core 33 are threadedly engaged with each other through the internal thread structure 104 and the external thread structure 331, so that the second intermediate body 102 follows the second mold core 33 and moves out of the second concave mold cavity 212, and then the second intermediate body 102 is rotated relative to the second mold core 33, and the threaded engagement between the second intermediate body 102 and the second mold core 33 is utilized to make the second intermediate body 102 drive the first intermediate body 101 and the heat shrinkable color film 103 to disengage from the male mold unit, thereby completing the molding of the lip glaze brush head.

[0052] In this embodiment, the first intermediate body 101 is first formed, and then a heat-shrinkable color film 103 with a color gradient effect is coated on one end of the outer peripheral wall of the first intermediate body 101, and then a second intermediate body 102 is secondary molded to cover one end of the first intermediate body 101 and the heat-shrinkable color film 103 to complete the injection-molded lip glaze brush head, thereby avoiding the use of a two-color injection molding process, which is beneficial to improving production efficiency and reducing production costs.

[0053] like Figure 2 , Figure 5 , Figure 6 , Figures 9 to 11As shown, in the integrated injection molding device described in this embodiment, in some embodiments, the die ring 21 is provided with a film feeding assembly between the first die cavity 211 and the second die cavity 212;

[0054] The film feeding assembly includes a feeder 22, a feeding cavity 213 arranged on the die ring 21, and a heating tube 23 arranged on the inner wall of the feeding cavity 213; tear lines for breaking the heat shrinkable color film 103 are arranged at equal intervals on the heat shrinkable color film 103. When the first intermediate 101 is inserted into the heating tube 23, the feeder 22 transports the heat shrinkable color film 103 to between the periphery of the first intermediate 101 and the heating tube 23. The heating tube 23 heats the heat shrinkable color film 103, so that the heat shrinkable color film 103 shrinks and covers the outer peripheral wall of the first intermediate 101.

[0055] Specifically, when the rotating frame 31 drives the second mold core 33 and the molded first intermediate 101 to rotate until the second mold core 33 is located directly above the feeding cavity 213, the rotating frame 31 drives the second mold core 33 and the first intermediate 101 to be inserted into the heating tube 23, and the feeder 22 transports the heat shrinkable color film 103 to between the heating tube 23 and the first intermediate 101. However, the heat shrinkable color film 103 is heated by the heating tube 23, so that the heat shrinkable color film 103 shrinks and is coated on the outer peripheral wall of the first intermediate 101. The heat shrinkable color film 103 is separated from the remaining heat shrinkable color films 103 through the tear line during the heat shrinking process, thereby completing the process of the heat shrinkable color film 103 coating the outer peripheral wall of the first intermediate 101.

[0056] like Figures 1 to 3 , Figure 5 , Fig. 9 , Figure 12 to Figure 14 As shown, in the integrated injection molding equipment described in this embodiment, in some embodiments, a push rod 4 is arranged on the top of the injection molding frame 1, and the output end of the push rod 4 is rotatably connected to the rotating frame 31; the rotating frame 31 has a driving shaft 311, and the outer wall of the driving shaft 311 is provided with multiple groups of driving grooves connected end to end in sequence along the circumferential direction, such as four groups of driving grooves; the injection molding frame 1 is elastically floatingly connected with a driving pin 5, and the driving pin 5 is movably embedded in the driving groove, and the rotating frame 31 can be driven to rotate by the cooperation between the driving pin 5 and the driving groove; multiple groups of concave mold forming units are arranged on the concave mold ring 21 along the circumferential direction, such as four groups of concave mold forming units; multiple groups of punch units are arranged on the rotating frame 31, such as four groups of punch units.

[0057] In this embodiment, the push rod 4 drives the rotating frame 31 to move up and down to close and open the mold between the male mold unit and the female mold molding unit. The driving pin 5 cooperates with the driving groove, so that the rotating frame 31 drives the male mold unit to cooperate with the first female mold cavity 211 and the second female mold cavity 212 in sequence to perform injection molding of the first intermediate 101 and the second intermediate 102. By providing multiple groups of female mold molding units, multiple groups of male mold units and multiple groups of driving grooves, injection molding of multiple lip glaze brush heads can be performed simultaneously, thereby further improving production efficiency and reducing production costs.

[0058] like Fig.13 As shown, the one-piece injection molding device described in this embodiment, specifically, each group of driving grooves includes a first vertical groove 3121, a second vertical groove 3122 and a third vertical groove 3123 which are arranged side by side at intervals and whose depths gradually increase; the height of the lower end of the first vertical groove 3121, the height of the lower end of the second vertical groove 3122, and the height of the lower end of the third vertical groove 3123 decrease in sequence;

[0059] A first spiral groove 3124 is connected between the lower end of the first vertical groove 3121 and the lower end of the second vertical groove 3122, a second spiral groove 3125 is connected between the lower end of the second vertical groove 3122 and the lower end of the third vertical groove 3123, a third spiral groove 3126 is connected between the lower end of the third vertical groove 3123 and the lower end of the first vertical groove 3121 of the adjacent driving groove, a depth of one end of the third spiral groove 3126 is greater than the depth of the third vertical groove 3123, a depth of the other end of the third spiral groove 3126 is less than the depth of the first vertical groove 3121, and both ends of the third spiral groove 3126 are smoothly transitioned.

[0060] The integrated injection molding equipment described in this embodiment, further, when the driving pin 5 is located in the first vertical groove 3121, the second mold core 33 is located directly above the first concave mold cavity 211; when the driving pin 5 is located in the second vertical groove 3122, the second mold core 33 is located directly above the feeding cavity 213; when the driving pin 5 is located in the third vertical groove 3123, the second mold core 33 is located directly above the second concave mold cavity 212.

[0061] During the molding process, the driving pin 5 is located at the lower end of the first vertical groove 3121, and the push rod 4 drives the rotating frame 31 to move downward. At this time, the second mold core 33 is aligned with the first concave mold cavity 211 until the second mold core 33 is inserted into the first concave mold cavity 211 to form a first molding cavity, thereby injecting molten transparent plastic into the first molding cavity to form a first intermediate 101. Figure 4As shown, after the pressure is maintained, the push rod 4 drives the rotating frame 31 to move upward, so that the second mold core 33 drives the formed first intermediate 101 to move out of the first concave mold cavity 211 synchronously, and the driving pin 5 moves downward along the first vertical groove 3121 until the driving pin 5 moves to the lower end of the first vertical groove 3121. As the push rod 4 continues to drive the rotating frame 31 to move upward, the driving pin 5 enters the first spiral groove 3124 from the first vertical groove 3121. Under the cooperation of the driving pin 5 and the first spiral groove 3124, the rotating frame 31 drives the punch unit to rotate until the driving pin 5 enters the lower end position of the second vertical groove 3122 from the first spiral groove 3124. At this time, the second mold core 33 of the punch unit rotates to be directly above the feeding cavity 213.

[0062] At this time, the push rod 4 drives the rotating frame 31 to move downward, and the driving pin 5 moves upward along the second vertical groove 3122, so that the second mold core 33 drives the first intermediate 101 to be inserted into the heating tube 23, and the feeder 22 conveys the heat shrinkable color film 103 into the heating tube 23, and the heat shrinkable color film 103 is placed between the inner wall of the heating tube 23 and the first intermediate 101, and then the heating tube 23 works to heat the heat shrinkable color film 103, so that the heat shrinkable color film 103 shrinks and covers the first intermediate 101, as shown in FIG. Figure 6 As shown;

[0063] After completion, the push rod 4 drives the male mold unit to move upward, so that the first intermediate body 101 and the heat shrinkable color film 103 coated on the outer peripheral wall of the first intermediate body 101 are moved out of the heating tube 23, and the driving pin 5 moves downward along the second vertical groove 3122 to the lower end of the second vertical groove 3122, until the driving pin 5 enters the second spiral groove 3125 from the lower end of the second vertical groove 3122. At this time, under the cooperation of the driving pin 5 and the second spiral groove 3125, the rotating frame 31 rotates again, driving the second mold core 33 to rotate until the second mold core 33 is located directly above the second concave mold cavity 212, and at this time, the driving pin 5 enters the lower end of the third vertical groove 3123 from the second spiral groove 3125;

[0064] Then the push rod 4 pushes the rotating frame 31 downward again, so that the second mold core 33 drives the first intermediate body 101 and the heat shrinkable color film 103 to be inserted into the second concave mold cavity 212 to form a second molding cavity, and then the second intermediate body 102 covering the first intermediate body 101 and the heat shrinkable color film 103 is injection molded. Figure 8As shown, after the pressure is maintained, the push rod 4 drives the rotating frame 31 to move upward, so that the second intermediate body 102, the first intermediate body 101 and the heat shrinkable color film 103 are synchronously moved out of the second concave mold cavity 212, and the driving pin 5 moves to the lower end of the third vertical groove 3123 and enters the third spiral groove 3126 from the third vertical groove 3123. At this time, the rotating frame 31 drives the male mold unit to rotate. During the rotation process, the external thread structure 331 of the second mold core 33 and the internal thread structure 104 of the second intermediate body 102 are used to make the formed lip glaze brush head detach from the male mold unit, thereby completing the injection molding process of the lip glaze brush head, until the driving pin 5 enters the lower end of the first vertical groove 3121 of the adjacent driving groove through the third spiral groove 3126. At this time, the male mold unit rotates to correspond to the adjacent female mold molding unit up and down;

[0065] Such a cyclic operation continuously performs the injection molding process of the lip gloss brush head, which greatly improves the production efficiency and reduces the production cost.

[0066] like Figure 1 , Figure 2 , Fig. 9 and Fig.10 As shown, in the integrated injection molding equipment described in this embodiment, in some embodiments, the die ring 21 is provided with a feed chute 24 between adjacent die molding units, the injection molding machine frame 1 is provided with a friction plate 6 above the feed chute 24, and the outer wall of the second mold core 33 is provided with a friction wheel 34. When the friction wheel 34 is in friction contact with the friction plate 6, the friction wheel 34 drives the second mold core 33 to rotate.

[0067] Specifically, when the driving pin 5 moves along the trajectory of the third spiral groove 3126, the rotating frame 31 rotates, and the rotating frame 31 drives the friction wheel 34 of the punch unit to rotate, so that the friction wheel 34 contacts the friction plate 6. The friction wheel 34 rotates under the drive of the friction plate 6, and drives the second mold core 33 to rotate relatively. During the rotation of the second mold core 33, the external thread structure 331 and the internal thread structure 104 cooperate to make the formed lip glaze brush head detach from the punch unit. The detached lip glaze brush head falls onto the discharge chute 24 and moves out of the working area along the discharge chute 24.

[0068] like Figures 1 to 3 , Figure 5 and Figure 7 As shown, in the one-piece injection molding device described in this embodiment, in some embodiments, the injection molding frame 1 is provided with a center hole coaxially arranged with the die ring 21, the drive shaft 311 movably passes through the center hole, and a return spring 7 is connected between the drive shaft 311 and the injection molding frame 1 along the axial direction of the drive shaft 311. In this embodiment, the return spring 7 is provided to facilitate the return movement of the rotating bracket.

[0069] like Figures 2 to 11As shown, in the integrated injection molding device described in this embodiment, in some embodiments, the position of the injection molding frame 1 corresponding to the first molding cavity is provided with a first glue injection nozzle 8, and the position corresponding to the second molding cavity is provided with a second glue injection nozzle 9. In this embodiment, the first glue injection nozzle 8 and the second glue injection nozzle 9 are provided to inject molten transparent plastic into the first molding cavity and inject molten transparent plastic into the second molding cavity.

[0070] like Figures 1 to 18 As shown, this embodiment also provides an integrated injection molding method, which is implemented by the above-mentioned integrated injection molding device and specifically includes the following steps:

[0071] Step S1: injection molding a first intermediate body 101 in a first molding cavity;

[0072] Step S2: coating one end of the outer peripheral wall of the first intermediate body 101 with a heat shrinkable color film 103;

[0073] Step S3: injection molding the second intermediate body 102 covering the lower end of the first intermediate body 101 and the heat shrinkable color film 103 in the second molding cavity, and molding the internal thread structure 104 at the upper end of the inner wall of the second intermediate body 102 .

[0074] In this embodiment, the first intermediate body 101 is first formed, and then a heat-shrinkable color film 103 with a color gradient effect is coated on one end of the outer peripheral wall of the first intermediate body 101, and then a second intermediate body 102 is secondary molded to cover one end of the first intermediate body 101 and the heat-shrinkable color film 103 to complete the injection-molded lip glaze brush head, thereby avoiding the use of a two-color injection molding process, which is beneficial to improving production efficiency and reducing production costs.

[0075] The above description is only a preferred embodiment of the present invention. Therefore, any equivalent changes or modifications made according to the structure, characteristics and principles described in the scope of the patent application of the present invention are included in the protection scope of the patent application of the present invention.

Claims

1. An integrated injection molding device for a lip glaze brush head, characterized in that: The invention comprises an injection molding machine frame, on which a concave mold assembly and a rotating convex mold assembly arranged above the concave mold assembly are arranged; The die assembly comprises a die ring, a die forming unit is arranged on the die ring, and the die forming unit comprises a first die cavity and a second die cavity which are arranged on the die ring at intervals; The rotary punch assembly comprises a rotary frame, on which a punch unit is arranged; the punch unit comprises a first mold core and a second mold core rotatably sleeved on the lower end of the outer peripheral wall of the first mold core, the second mold core is provided with an external thread structure, and the first mold core is provided with a rod forming cavity; When the second mold core is inserted into the first concave mold cavity, the first mold core, the second mold core, the first concave mold cavity and the rod molding cavity together form a first molding cavity; when the second mold core is inserted into the second concave mold cavity, the second mold core, the first intermediate body and the second concave mold cavity together form a second molding cavity; The die ring is provided with a film feeding assembly between the first die cavity and the second die cavity; The film feeding assembly includes a feeder, a feeding cavity arranged on a die ring, and a heating tube arranged on the inner wall of the feeding cavity; easy-tear lines for breaking the heat-shrinkable color film are arranged at equal intervals on the heat-shrinkable color film; when the first intermediate is inserted into the heating tube, the feeder conveys the heat-shrinkable color film to between the outer periphery of the first intermediate and the heating tube, and the heating tube heats the heat-shrinkable color film so that the heat-shrinkable color film shrinks and covers the outer peripheral wall of the first intermediate; A push rod is arranged on the top of the injection molding frame, and the output end of the push rod is rotatably connected to the rotating frame; the rotating frame has a driving shaft, and the outer wall of the driving shaft is provided with a plurality of driving grooves connected end to end in the circumferential direction; the injection molding frame is elastically and floatingly connected with a driving pin, and the driving pin is movably embedded in the driving groove, and the rotating frame can be driven to rotate by the driving pin and the driving groove cooperating with each other; A plurality of groups of concave die forming units are arranged on the concave die ring along the circumferential direction; and a plurality of groups of convex die units are arranged on the rotating frame.

2. The one-piece injection molding device for a lip glaze brush head according to claim 1, characterized in that: Each set of driving grooves includes a first vertical groove, a second vertical groove and a third vertical groove which are arranged side by side at intervals and have gradually increasing depths; the height of the lower end of the first vertical groove, the height of the lower end of the second vertical groove and the height of the lower end of the third vertical groove decrease in sequence; A first spiral groove is connected between the lower end of the first vertical groove and the lower end of the second vertical groove, a second spiral groove is connected between the lower end of the second vertical groove and the lower end of the third vertical groove, a third spiral groove is connected between the lower end of the third vertical groove and the lower end of the first vertical groove of the adjacent driving groove, a depth of one end of the third spiral groove is greater than the depth of the third vertical groove, a depth of the other end of the third spiral groove is less than the depth of the first vertical groove, and both ends of the third spiral groove are smoothly transitioned.

3. The one-piece injection molding device for a lip glaze brush head according to claim 2, characterized in that: When the drive pin is located in the first vertical groove, the second mold core is located directly above the first die cavity; when the drive pin is located in the second vertical groove, the second mold core is located directly above the feeding cavity; when the drive pin is located in the third vertical groove, the second mold core is located directly above the second die cavity.

4. The one-piece injection molding device for a lip glaze brush head according to claim 1, characterized in that: The die ring is provided with a feed trough between adjacent die forming units, the injection molding machine frame is provided with a friction plate above the feed trough, and the outer wall sleeve of the second mold core is provided with a friction wheel. When the friction wheel is in friction contact with the friction plate, the friction wheel drives the second mold core to rotate.

5. The one-piece injection molding device for a lip glaze brush head according to claim 1, characterized in that: The injection molding machine frame is provided with a center hole coaxially arranged with the die ring, the driving shaft movably passes through the center hole, and a return spring is connected between the driving shaft and the injection molding machine frame along the axial direction of the driving shaft.

6. The one-piece injection molding device for a lip glaze brush head according to claim 1, characterized in that: The injection molding machine frame is provided with a first glue injection nozzle at a position corresponding to the first molding cavity, and a second glue injection nozzle at a position corresponding to the second molding cavity.

7. A one-piece injection molding method for a lip glaze brush head, characterized in that: Using the one-piece injection molding device according to any one of claims 1 to 6, the method comprises the following steps: S1: injection molding a first intermediate in a first molding cavity; S2: Covering one end of the peripheral wall of the first intermediate with a layer of heat shrinkable color film; S3: Injection molding a second intermediate body covering the lower end of the first intermediate body and the heat shrinkable color film in the second molding cavity, and molding an internal thread structure at the upper end of the inner wall of the second intermediate body.

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