Single-side injection mold for transparent plastic mask

Abstract

The utility model relates to a transparent plastic mask unilateral injection mould, including upper mould body and lower mould body, the upper mould body includes upper fixed plate, hot runner plate, needle valve hot runner, fixed template, the fixed template is equipped with the cavity, the lower mould body includes lower fixed plate, two mould foot, first top plate, second top plate, movable template, the movable template is equipped with the mould core, the mould foot is equipped with the first top plate, the second top plate is equipped with the first top plate, the second top plate is equipped with the second top plate. A mask forming area used for forming a mask body is formed between the mold core and the mold cavity, the movable mold is provided with a first forming area used for forming a connecting part and a first injection molding runner, the first forming area is communicated with the mask forming area, and a pouring inlet communicated with the first forming area is formed in the side wall of the first injection molding runner; the pouring gate is positioned on one side, far away from the mold core, of the first forming area. The pouring gate is communicated with the first forming area to control a pouring gate scar on the connecting part, so that the appearance quality of the mask body is guaranteed.

Description

Technical Field

[0001] This utility model relates to the field of molds, and in particular to a single-sided injection mold for a transparent plastic face mask. Background Technology

[0002] A transparent plastic face mask, such as Figure 1 As shown, the mask includes a face mask body 9. One end of the face mask body 9 has a connecting portion 91 for assembly, and the connecting portion 91 has several annular first reinforcing ribs 92. The other end of the face mask body 9 has second reinforcing ribs 93. After assembly, the connecting portion 91 is covered, leaving the entire face mask body 9 exposed. Because the face mask body 9 is a transparent part, any appearance defects produced during injection molding will be very noticeable. However, since the face mask body 9 is a plastic part, gate scars will form between the face mask body 9 and the gate during injection molding, which will undoubtedly directly affect the appearance quality of the face mask body 9. Utility Model Content

[0003] This application provides a single-sided injection mold for a transparent plastic face mask, which controls gate scars on the connection part by connecting the gate to the first molding area, thereby ensuring the appearance quality of the face mask body.

[0004] The technical solution for a single-sided injection mold of a transparent plastic face mask provided in this application is as follows:

[0005] A single-sided injection mold for a transparent plastic face mask includes an upper mold body and a lower mold body. The upper mold body includes an upper fixed plate, a hot runner plate, a needle valve hot runner, and a fixed mold plate. The fixed mold plate has a cavity. The lower mold body includes a lower fixed plate, two mold feet, a first top plate, a second top plate, and a movable mold plate. The movable mold plate has a core. The movable mold plate has a first molding area and a first injection runner for molding the connecting part. The first molding area is connected to the face mask molding area. The side wall of the first injection runner has a gate that connects to the first molding area. The gate is located on the side of the first molding area away from the core.

[0006] By adopting the above technical solution, the gate scars are controlled at the connection point by connecting the gate to the first molding zone, thereby ensuring the appearance quality of the mask body. Simultaneously, in the initial stages of product injection molding, the hot melt plastic absorbs some heat from the mold. This portion of the hot melt plastic, when injected into the product, results in poor gloss and other appearance conditions. To address this, by connecting the gate to the first molding zone, the lower-temperature hot melt plastic from the initial injection molding process is used to mold the connection point, while the more appropriately heated hot melt plastic from the later stages of injection molding is used to mold the mask body, thus ensuring the molding effect of the mask body.

[0007] Preferably, the first injection runner is U-shaped, the needle valve hot runner includes a hot runner body and a needle valve tube, the outlet of the needle valve tube is connected to one end of the first injection runner, and the inlet is located on the side wall of the first injection runner away from the needle valve tube.

[0008] By adopting the above technical solution, the hot melt plastic flowing out of the needle valve tube will not directly rush into the gate, thereby preventing the hot melt plastic from being sprayed and filled during the molding of the mask body, and thus preventing watermarks from appearing on the surface of the mask body during molding.

[0009] Preferably, the cavity has a U-shaped second injection runner, the needle valve tube of the needle valve hot runner extends into the second injection runner, and the cross-sections of the first injection runner and the second injection runner of the needle valve hot runner are both semi-circular. When the mold is closed, the first injection runner and the second injection runner are interconnected to form a tubular injection cavity.

[0010] By adopting the above technical solution, the tubular injection cavity offers less resistance to the flow of hot-melt plastic compared to other types of injection cavities of the same diameter. This better ensures the direct injection pressure of the hot-melt plastic, allowing for a full injection of the mask body. Simultaneously, the tubular shape of the injection cavity allows some of the hot-melt plastic to better adhere to the cavity wall during the initial injection molding process, forming a heat insulation layer. This reduces heat loss from the hot-melt plastic in subsequent processes and prevents shrinkage and sticking issues caused by low temperatures during the hot-melt plastic molding of the mask body.

[0011] Preferably, a through hole is provided on the bottom surface of the first injection channel, the through hole being directly opposite the outlet of the needle valve tube, and a push rod is provided on the second top plate, the top end of the push rod extending into the through hole.

[0012] By adopting the above technical solution, when the face mask body needs to be demolded during injection molding, the injection molding machine will drive the second top plate to move. When the second top plate moves, it will drive the ejector rod to move. When the ejector rod moves, it will push the waste material out from the first injection channel.

[0013] Preferably, the moving template has two venting grooves, which are located on both sides of the first forming area and are connected to the first forming area. The fixed template has two protrusions. When the mold is closed, the two protrusions extend into the two venting grooves, forming two venting channels between the two protrusions and the two venting grooves. The two venting channels are respectively connected to the first forming area.

[0014] By adopting the above technical solution, the first molding area is located deep in the area where several first reinforcing ribs are formed. Therefore, air is easily trapped during the injection molding process, which prevents the hot melt plastic from filling the first molding area and causes the connection part to be incompletely formed. Therefore, by setting two exhaust channels, the air inside the hot melt plastic can be discharged into the two exhaust channels when filling the first molding area, thereby preventing the connection part from being incompletely formed.

[0015] Preferably, the distance from the inlet to the two venting slots is equal.

[0016] By adopting the above technical solution, when the hot melt plastic enters the first molding area through the gate, it will diffuse to both sides of the first molding area and fill the first molding area. The gate is set between the two venting grooves so that the hot melt plastic that diffuses to both sides of the first molding area can fill the first molding area together at about the same time and diffuse into the mask molding area at the same time, thereby reducing the probability of weld lines being generated in the mask body due to the collision of hot melt plastic in the mask molding area.

[0017] Preferably, the moving template has an installation groove, the installation groove has a forming insert, the forming insert has a first forming groove on the side facing the core, the core has a second forming groove, the first forming groove and the second forming groove together form a second forming area for forming the second reinforcing rib, the forming insert has multiple bolts threadedly connected, and the bottom wall of the installation groove has multiple threaded holes for connecting with the bolts.

[0018] By adopting the above technical solution, it is convenient for workers to polish the first and second molding grooves, thereby reducing the probability of surface scratches during the demolding process of the second reinforcing rib.

[0019] Preferably, the moving template is slidably connected with a plurality of top blocks, each of the top blocks having a connecting hole at its bottom, each of the connecting holes having a connecting rod inside, the bottom ends of each of the connecting rods being disposed on a second top plate, and each of the top blocks having a fixing member for fixing the connecting rod in the connecting hole.

[0020] By adopting the above technical solution, after the mask body is injection molded, the injection molding machine drives the first top plate and the second top plate to move together toward the moving template. When the second top plate moves, it will drive several connecting rods to move. When the connecting rods move, they will drive several top blocks to move, so that the mask body after the top blocks are formed will be ejected from the core.

[0021] Preferably, the top blocks are arranged in pairs opposite each other on both sides of the core.

[0022] By adopting the above technical solution, the force is more even when the top block pushes out of the mask body, preventing the mask body from deforming when it is pushed out by the top block.

[0023] Preferably, the top block has a mounting hole on its side wall, the axis of the mounting hole is perpendicular to the axis of the connecting hole, the mounting hole is connected to the connecting hole, the fixing member is a locking pin that is snapped into the mounting hole, the top end of the connecting rod has a limiting groove, the limiting groove is connected to the mounting hole, and the end of the locking pin away from the opening of the mounting hole is inserted into the limiting groove.

[0024] By adopting the above technical solution, it is convenient to install the connecting rod and the top block. When the connecting rod is installed on the top block, first insert the top of the connecting rod into the connecting hole, then rotate the top rod to make the limiting groove connect with the installation hole, and then insert the locking column into the installation hole while making the locking column teahouse in the limiting groove.

[0025] The main technical effects of this utility model are reflected in the following aspects:

[0026] 1. This utility model controls the gate scars on the connection part by connecting the gate to the first molding area, thereby ensuring the appearance quality of the mask body;

[0027] 2. This utility model features a tubular injection cavity to prevent watermarks from forming on the surface of the mask body during molding;

[0028] 3. This utility model provides two exhaust channels so that when the hot melt plastic fills the first molding area, the air inside can be discharged into the two exhaust channels, thereby preventing incomplete molding of the connecting part. Attached Figure Description

[0029] Figure 1 This is a schematic diagram of the mask body.

[0030] Figure 2 This is a structural schematic diagram of the mold used in this application.

[0031] Figure 3 yes Figure 2 A schematic diagram of the upper and middle phantoms.

[0032] Figure 4 yes Figure 2 Schematic diagram of the middle and lower mold body.

[0033] Figure 5 yes Figure 4 A schematic diagram of the structure of the lower and middle mold body after removing the moving template.

[0034] Figure 6 yes Figure 2 A schematic diagram of the structure of the moving template.

[0035] Figure 7 yes Figure 6 A magnified view of a portion of point A in the middle.

[0036] Figure 8 yes Figure 2 A cross-sectional view of the middle mold along the BB line.

[0037] Figure 9 yes Figure 8 A magnified view of a section at point C.

[0038] Figure 10 yes Figure 2 A cross-sectional view of the fixed template and the moving template along line DD.

[0039] Figure 11 yes Figure 10 A magnified view of a section at point E in the middle.

[0040] Figure 12 yes Figure 8 A magnified view of a section at point F.

[0041] Figure 13 This is a schematic diagram of the structure of the molded insert.

[0042] Figure 14 This is a schematic diagram of the hot runner structure of a needle valve.

[0043] Figure 15 This is a structural diagram of the top block and connecting rod.

[0044] Figure 16 yes Figure 15 Partial sectional view of the top block and connecting rod.

[0045] Reference numerals: 1. Upper mold body; 11. Upper fixed plate; 12. Hot runner plate; 13. Needle valve hot runner; 131. Hot runner body; 132. Needle valve tube; 14. Fixed mold plate; 141. Cavity; 142. Second injection runner; 143. Protrusion; 2. Lower mold body; 21. Lower fixed plate; 211. Guide pillar; 22. Mold foot; 23. First ejector plate; 24. Second ejector plate; 241. Ejector rod; 25. Moving mold plate; 251. First molding zone; 252. First injection runner; 253. Gate; 254. Through hole; 25 5. Venting groove; 256. Mounting groove; 257. Threaded hole; 3. Core; 31. Second molding groove; 4. Ejector rod; 5. Molding insert; 51. First molding groove; 52. Bolt; 6. Ejector block; 61. Connecting hole; 62. Mounting hole; 7. Connecting rod; 71. Limiting groove; 8. Fixing component; 81. Locking post; 9. Mask body; 91. Connecting part; 92. Annular first reinforcing rib; 93. Second reinforcing rib; 101. Tubular injection cavity; 102. Venting channel; 103. Second molding area; 104. Mask molding area. Detailed Implementation

[0046] The present application will be further described in detail below with reference to the accompanying drawings, so that the technical solution of the present application can be more easily understood and mastered.

[0047] Reference Figure 2 , Figure 3 and Figure 14 This embodiment includes an upper mold body 1 and a lower mold body 2. The upper mold body 1 includes an upper fixed plate 11, a hot runner plate 12, a needle valve hot runner 13, and a fixed mold plate 14. The hot runner plate 12 is fixed to the upper fixed plate 11, the needle valve hot runner 13 is fixed to the hot runner plate 12, and the fixed mold plate 14 is fixed to the hot runner plate 12. The fixed mold plate 14 has a cavity 141, and a U-shaped second injection runner 142 is formed in the cavity 141. The needle valve hot runner 13 includes a hot runner body 131 and a needle valve tube 132, with the needle valve tube 132 extending into the second injection runner 142.

[0048] Reference Figure 2 and Figure 4 The lower mold body 2 includes a lower fixed plate 21, two mold feet 22, a first top plate 23, a second top plate 24, and a movable template 25. The two mold feet 22 are fixed to both ends of the lower fixed plate 21, and the movable template 25 is fixed to two mold plates. The first top plate 23 and the second top plate 24 are fixed to each other, with the second top plate 24 located on the side of the first top plate 23 away from the lower fixed plate 21. Several guide pillars are fixedly connected between the movable template 25 and the lower fixed plate 21, and the first top plate 23 and the second top plate 24 slide along the mold opening direction and are connected to the guide pillars.

[0049] Reference Figure 2 , Figure 4 , Figure 5 , Figures 7-9 The moving mold plate 25 is provided with a core 3, and a mask forming area 104 for forming the mask body 9 is formed between the core 3 and the cavity 141. The moving mold is provided with a first forming area 251 for forming the connecting part 91, and the first forming area 251 is connected to the mask forming area 104. Two push rods are fixedly connected to the second top plate 24, and the top ends of the two push rods extend into the first forming area 251.

[0050] Reference Figure 2 , Figures 4-9The moving mold is provided with a first injection runner 252, which is U-shaped and located on the side of the first molding area 251 away from the core 3. The cross-sections of the first injection runner 252 and the second injection runner 142 are both semi-circular. The first injection runner 252 and the second injection runner 142 are interconnected to form a tubular injection cavity 101. The needle valve tube 132 extends into one end hole of the first injection runner 252. The side wall of the first injection runner 252 away from the needle valve tube 132 is provided with a gate 253 that connects to the first molding area 251. At the same time, a through hole 254 is provided on the bottom surface of the first injection runner 252, which is directly opposite the outlet of the needle valve tube 132. A ejector rod (4) is fixedly connected to the second top plate 24, and the top end of the ejector rod (4) extends into the through hole 254.

[0051] Reference Figures 2-4 , Figure 7 , Figures 10-11 The moving mold plate 25 has two venting grooves 255 along the mold opening direction perpendicular to the mold. The two venting grooves 255 are located on both sides of the first forming area 251, and both venting grooves 255 are connected to the first forming area 251. The fixed mold plate 14 has two protrusions 143, which extend into the two venting grooves 255. The two protrusions 143 and the two venting grooves 255 form two venting channels 102. The distance from the gate 253 to the two venting grooves 255 is equal, and the two venting channels 102 are connected to the first forming area 251 respectively.

[0052] Reference Figure 2 , Figure 4 , Figure 6 , Figure 8 , Figure 12 , Figure 13 The moving template 25 also has an installation groove 256, which is located on the side of the core 3 away from the first forming area 251. A forming insert 5 is provided inside the installation groove 256, and two bolts 52 are threadedly connected to the forming insert 5. Two threaded holes 257 for connecting the bolts 52 are provided on the bottom wall of the installation groove 256, and the two bolts 52 are threaded into the two threaded holes 257 respectively. A first forming groove 51 is provided on the side of the forming insert 5 facing the core 3, and a second forming groove 31 is provided on the core 3. The first forming groove 51 and the second forming groove 31 together form a second forming area 103 for forming the second reinforcing rib.

[0053] Reference Figure 2 , Figure 4 , Figure 5A number of top blocks 6 are slidably connected to the moving template 25 along the mold opening direction. The top blocks 6 are arranged in pairs opposite each other on both sides of the core 3. The bottom of each top block 6 is provided with a connecting hole 61 along the mold opening direction. A connecting rod 7 is installed in each connecting hole 61. The bottom end of each connecting rod 7 is fixed on the second top plate 24.

[0054] Reference Figure 2 , Figure 4 , Figure 5 , Figure 15 , Figure 16 As shown in the figure, each of the top blocks 6 is provided with a fixing member 8 for fixing the connecting rod 7 in the connecting hole 61. A mounting hole 62 is provided on the side wall of the top block 6, the axis of which is perpendicular to the axis of the connecting hole 61. The fixing member 8 is a locking post 81 that snaps into the mounting hole 62. A limiting groove 71 is provided at the top of the connecting rod 7, which communicates with the mounting hole 62. The locking post 81 is engaged within the mounting hole 62, with one end of the locking post 81 away from the opening of the mounting hole 62 inserted into the limiting groove 71.

[0055] The complete injection molding process of the mold in this application is as follows:

[0056] First, the injection molding machine controls the mold to close. Then, the hot runner 13 of the needle valve injects hot melt plastic into the tubular injection cavity 101 through the needle valve tube 132. The first hot melt plastic ejected will contact the cavity wall of the tubular injection cavity 101 and cool down to form a heat insulation layer, reducing the heat loss of the subsequent hot melt plastic. Another part of the hot melt plastic with a lower temperature will be retained in the through hole 254.

[0057] Subsequently, hot-melt plastic at a higher temperature flows into and fills the first molding zone 251 through the injection port, forcing air out of the first molding zone 251 into the two exhaust channels 102. After the hot-melt plastic fills the first molding zone 251, it enters the mask molding zone 104 to mold the mask body 9. After the hot-melt plastic fills the mask molding zone 104, it enters the second molding zone 103 to mold the second reinforcing rib 93. The mask molding zone 104 is filled with hot-melt plastic, and the injection molding machine maintains pressure on the product to prevent water from entering.

[0058] After the product pressure holding is completed, the injection molding machine controls the lower mold body 2 to move away from the upper mold body 1. After the mold is fully opened, the injection molding machine drives the first ejector plate 23 and the second ejector plate 24 to move towards the moving mold plate 25. The movement of the second ejector plate 24 will drive the ejector rod, two ejector rods, and several ejector blocks 6 to move synchronously. When the ejector rod moves, it will push the plastic waste located in the first injection runner 252 out of the first injection runner 252. When the two ejector rods move, they will push the connecting part 91 out of the first molding area 251. When the several ejector blocks 6 move, they will push the mask body 9 out of the core 3. The demolding of the transparent plastic mask is completed through the movement of the ejector rod, the two ejector rods, and the several ejector blocks 6.

[0059] After the transparent plastic face mask is demolded, the injection molding machine controls the first ejector plate 23 and the second ejector plate 24 to move and reset, and drives the ejector rod, two ejector pins, and several ejector blocks 6 to move and reset. After the first ejector plate 23 and the second ejector plate 24 have moved and reset, the injection molding machine controls the lower mold body 2 to move toward the upper mold body 1 so that the mold closes and begins the injection molding of the next transparent plastic face mask.

[0060] Of course, the above are just typical examples of this application. In addition, this application may have many other specific implementation methods. All technical solutions formed by equivalent substitution or equivalent transformation fall within the scope of protection claimed in this application.

Claims

1. A single-sided injection mold for a transparent plastic face mask, comprising an upper mold body (1) and a lower mold body (2), wherein the upper mold body (1) comprises an upper fixed plate (11), a hot runner plate (12), a needle valve hot runner (13), and a fixed template (14), wherein the fixed template (14) is provided with a cavity (141), and the lower mold body (2) comprises a lower fixed plate (21), two mold feet (22), a first top plate (23), a second top plate (24), and a movable template (25), wherein the movable template (25) is provided with a core (3), and a face mask forming area (104) for forming the face mask body (9) is formed between the core (3) and the cavity (141), characterized in that: The moving mold is provided with a first molding area (251) and a first injection runner (252) for molding the connecting part (91). The first molding area (251) is connected to the mask molding area (104). The side wall of the first injection runner (252) is provided with a gate (253) that is connected to the first molding area (251). The gate (253) is located on the side of the first molding area (251) away from the core (3).

2. The single-sided injection mold for a transparent plastic face mask according to claim 1, characterized in that: The first injection runner (252) is U-shaped. The needle valve hot runner (13) includes a hot runner body (131) and a needle valve tube (132). The outlet of the needle valve tube (132) is connected to one end of the first injection runner (252). The inlet (253) is located on the side wall of the first injection runner (252) away from the needle valve tube (132).

3. The single-sided injection mold for a transparent plastic face mask according to claim 2, characterized in that: The cavity (141) is provided with a U-shaped second injection channel (142), and the needle valve tube (132) extends into the second injection channel (142). The cross-sections of the first injection channel (252) and the second injection channel (142) are both semi-circular. When the mold is closed, the first injection channel (252) and the second injection channel (142) are interconnected to form a tubular injection cavity (101).

4. A single-sided injection mold for a transparent plastic face mask according to claim 2, characterized in that: The bottom surface of the first injection channel (252) is provided with a through hole (254), which is directly opposite the outlet of the needle valve tube (132). The second top plate (24) is provided with a push rod (4), the top end of which extends into the through hole (254).

5. A single-sided injection mold for a transparent plastic face mask according to claim 1, characterized in that: The moving template (25) has two venting grooves (255) on it. The two venting grooves (255) are located on both sides of the first forming area (251). The two venting grooves (255) are connected to the first forming area (251). The fixed template (14) has two protrusions (143). When the mold is closed, the two protrusions (143) extend into the two venting grooves (255). Two venting channels (102) are formed between the two protrusions (143) and the two venting grooves (255). The two venting channels (102) are connected to the first forming area (251) respectively.

6. A single-sided injection mold for a transparent plastic face mask according to claim 1, characterized in that: The distance from the inlet (253) to the two venting slots (255) is equal.

7. A single-sided injection mold for a transparent plastic face mask according to claim 1, characterized in that: The moving template (25) is provided with an installation groove (256), and a forming insert (5) is provided in the installation groove (256). A first forming groove (51) is provided on the side of the forming insert (5) facing the core (3), and a second forming groove (31) is provided on the core (3). The first forming groove (51) and the second forming groove (31) together form a second forming area (103) for forming the second reinforcing rib (93). Multiple bolts (52) are threadedly connected to the forming insert (5), and multiple threaded holes (257) for connecting with the bolts (52) are provided on the bottom wall of the installation groove (256).

8. A single-sided injection mold for a transparent plastic face mask according to claim 1, characterized in that: The moving template (25) is slidably connected to a plurality of top blocks (6), each of the top blocks (6) having a connecting hole (61) at its bottom, each of the connecting holes (61) having a connecting rod (7) inside, each of the connecting rods (7) having its bottom end on the second top plate (24), and each of the top blocks (6) having a fixing member (8) for fixing the connecting rod (7) inside the connecting hole (61).

9. A single-sided injection mold for a transparent plastic face mask according to claim 8, characterized in that: Several of the top blocks (6) are respectively arranged opposite each other on both sides of the core (3).

10. A single-sided injection mold for a transparent plastic face mask according to claim 8, characterized in that: The top block (6) has a mounting hole (62) on its side wall. The axis of the mounting hole (62) is perpendicular to the axis of the connecting hole (61). The mounting hole (62) is connected to the connecting hole (61). The fastener (8) is a locking pin (81) that is snapped into the mounting hole (62). The top end of the connecting rod (7) has a limiting groove (71) that is connected to the mounting hole (62). The end of the locking pin (81) away from the opening of the mounting hole (62) is inserted into the limiting groove (71).

Images