A forced demolding structure for paper-plastic molds

Abstract

This utility model discloses a forced demolding structure for paper-plastic molds. The portion of the forced demolding structure installed on the upper mold includes a top plate, an ejector spring, and a limiting screw. The top plate is located at the bottom of the upper mold. The ejector spring and the limiting screw are both vertically arranged. One end of the limiting screw is fixedly connected to the top plate, and the other end is slidably connected to a groove inside the upper mold. A limiting surface is provided at the end of the groove to limit the sliding height of the limiting screw. At least a portion of the top plate forms the forming surface of the upper mold. A locking structure is also provided between the top plate and the upper mold. The portion of the forced demolding structure installed on the lower mold includes a guide block, which is used to switch between two states of the locking structure. This utility model provides a pop-out top plate structure for demolding the formed paper-plastic product. By eliminating the air-blowing demolding method, energy consumption is saved, and the formation of dirt by air blowing is avoided, thus improving the production environment.

Description

Technical Field

[0001] This utility model relates to the field of paper-plastic mold technology, specifically a forced demolding structure for paper-plastic molds. Background Technology

[0002] Existing paper cups are typically produced using paper-plastic molds, and most current paper cups have an inverted structure. (Refer to...) Figure 7 As shown in the diagram, point R is the inverted structure. This structure can cause some interference during demolding after the mold is formed. (Refer to...) Figure 8 As shown in the figure, point r is the forming convex surface of the undercut structure. As can be seen from the figure, the undercut structure and its forming convex surface interlock in the vertical direction, causing interference and making it difficult to demold the product.

[0003] The existing process is as follows: 1. In the slurry tank, the slurry is sucked into the required product shape by a suction mold. The suction mold is then raised to perform wet pre-forming dehydration.

[0004] 2. After the hot press upper mold is moved onto the suction mold for mold closing, the suction mold blows air, and the hot press upper mold sucks in air, transferring the wet blank to the hot press upper mold.

[0005] 3. The hot press upper mold moves together with the wet blank to the top of the hot press lower mold, and the mold is closed and heated to evaporate the moisture of the wet blank to about 5% of the water content. At the moment of mold opening, the hot press upper mold blows air through the air hole to force the dry product to the hot press lower mold. Because the product has an internal buckle structure, it cannot be demolded. It is necessary to use a lot of air pressure to blow the product out of shape and then remove the buckle.

[0006] The above-mentioned air blowing method for demolding has the following problems: (1) Air blowing will break the loose paper fibers at the edge of the product and cause them to fly around on the machine table and fall into the mold cavity, resulting in dirt (paper scraps, dust, etc.) when the product is pressed and molded for the second time. Currently, the product defects caused by dirt reach 10% to 15%;

[0007] (2) Because high-pressure compressed air of 2.0 MPa or higher is used to blow the product, the cost of compressed air accounts for 10% of the total cost;

[0008] (3) The equipment needs to be shut down for one day out of every five days for maintenance, because the equipment gets very dirty due to the air blowing. This will affect the daily production capacity. Summary of the Invention

[0009] Technical problems to be solved

[0010] The purpose of this invention is to overcome the shortcomings of the existing technology and provide a forced demolding structure for paper-plastic molds.

[0011] Technical solution

[0012] To achieve the above objectives, this utility model provides the following technical solution: a forced demolding structure for a paper-plastic mold, wherein the forced demolding structure is installed on the upper mold and includes a top plate, an ejector spring, and a limiting screw. The top plate is located at the bottom of the upper mold, and the ejector spring and the limiting screw are both vertically arranged. One end of the limiting screw is fixedly connected to the top plate, and the other end of the limiting screw is slidably connected to a slide groove in the upper mold. A limiting surface is provided at the end of the slide groove to limit the height of the limiting screw as it slides down.

[0013] At least part of the top plate forms the forming surface of the upper mold;

[0014] A locking structure is also provided between the top plate and the upper mold. The locking structure has two states: in the locked state, the top plate and the upper mold are in close contact and locked together, and the top plate does not have a tendency to move away from the upper mold under the action of the ejector spring.

[0015] In the unlocked state, the top plate is disengaged from the upper mold, and the top plate tends to move away from the upper mold under the action of the ejector spring;

[0016] The forced demolding structure is the part installed on the lower mold, including a guide block, which is used to switch between the two states of the locking structure.

[0017] As mentioned above, the forming surface of the upper mold consists of a central forming surface and an edge forming surface, with the edge forming surface located on the top plate.

[0018] As mentioned above, the top plate is distributed in a ring around the outer side of the middle forming surface of the upper mold, and the middle forming surface of the upper mold has a forming convex surface that forms the inner buckle structure of the paper cup.

[0019] The aforementioned locking structure includes a hook mounted on the top plate and a connecting plate mounted on one side of the hook.

[0020] It also includes the hanging plate and push plate set in the upper mold;

[0021] The upper part of the hook bends towards the side of the hanging plate, and the lower part of the hook is rotatably connected to the top plate;

[0022] In the locked state, the upper part of the hook is attached to the hanging plate, which limits the downward movement of the top plate;

[0023] When unlocked, the hook is detached from the mounting plate.

[0024] As mentioned above, a return spring is horizontally connected between the connecting plate and the hook, and the return spring causes the upper part of the hook to tend to swing towards the side of the hanging plate.

[0025] The push plate is slidably connected to the upper mold and can slide along the horizontal direction. The push plate can push open the hooks mounted on the hanging plate, so that the locking structure switches from the locked state to the unlocked state.

[0026] As mentioned above, the hanging plate is set vertically, and the upper end of the hanging plate is used to connect with the hook. The length of the hanging plate is greater than or equal to the maximum distance between the top plate and the upper mold.

[0027] As described above, the suction mold is provided with a first guide block, and a first guide groove is provided on the first guide block. When the upper mold closes with the suction mold downwards, the guide shaft on the push plate is accommodated in the first guide groove. When the upper mold separates from the suction mold, the first guide groove guides the push plate to slide away from the hook.

[0028] As mentioned above, the hot-pressing lower mold is provided with a second guide block, and a second guide groove is provided on the second guide block. When the upper mold closes with the hot-pressing lower mold downwards, the guide shaft on the push plate is accommodated in the second guide groove. When the upper mold separates from the suction lower mold, the first guide groove guides the push plate to slide toward the hook.

[0029] Beneficial effects:

[0030] Compared with existing technologies, this forced demolding structure for paper-plastic molds has the following advantages:

[0031] This utility model provides a forced demolding structure for paper-plastic molds. The utility model is equipped with a pop-out top plate structure for demolding the formed paper-plastic products. By eliminating the air blowing demolding method, energy consumption is saved, and the formation of dirt by air blowing is also avoided, thus improving the production environment.

[0032] Other advantages, objectives and features of this invention will be set forth in part in the description which follows, and in part will be apparent to those skilled in the art from the following examination or study, or may be taught from the practice of this invention. Attached Figure Description

[0033] Figure 1 This is a schematic diagram of the overall structure of this utility model;

[0034] Figure 2 This is a schematic diagram of the installation position of the top plate structure of this utility model;

[0035] Figure 3 This is a schematic diagram of the structure of the present invention after the upper mold and the lower hot-pressing mold are separated;

[0036] Figure 4 This is a schematic diagram of the structure of the present invention after the upper mold and the lower mold for suction are separated;

[0037] Figure 5 This is a schematic diagram of the structure of the upper mold and the suction mold after they are closed.

[0038] Figure 6This is a schematic diagram of the structure of the upper mold and the lower hot-pressing mold after they are closed.

[0039] Figure 7 This is a schematic diagram of the inverted structure of the molded product of this utility model;

[0040] Figure 8 This is a schematic diagram of the mold forming surface and the structure of the molded product of this utility model. Detailed Implementation

[0041] The technical solutions of the present utility model will be clearly and completely described below with reference to the accompanying drawings of the embodiments. Obviously, the described embodiments are only some embodiments of the present utility model, and not all embodiments. Based on the embodiments of the present utility model, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the protection scope of the present utility model.

[0042] like Figure 1-6 As shown, this utility model provides a technical solution: (Refer to...) Figure 1 As shown, it includes an upper mold 2, a suction mold 4, and a hot-pressing mold 3;

[0043] The suction mold 4 is located in the slurry pool 5, and a lifting mechanism is installed at the bottom of the suction mold 4.

[0044] Both the upper mold 2 and the lower mold 4 are equipped with blowing and suction components, and both the upper mold 2 and the lower mold 4 have air-passing screen holes on their surfaces.

[0045] The upper mold 2 is positioned on a transferable path to allow switching between a position above the suction mold 4 and a position above the hot-pressing mold 3;

[0046] The upper mold 2 is provided with a demolding structure, which includes a top plate 21, an ejector spring 22 and a limiting screw 23. The top plate 21 is located at the bottom of the upper mold 2. The ejector spring 22 and the limiting screw 23 are both vertically arranged. One end of the limiting screw 23 is fixedly connected to the top plate 21, and the other end of the limiting screw 23 is slidably connected to the slide groove in the upper mold 2. A limiting surface is provided at the end of the slide groove to limit the height of the limiting screw 23 as it slides down.

[0047] At least a portion of the top plate 21 forms the forming surface of the upper mold 2; see reference. Figure 1 and Figure 2 As shown, the top plate 21 is distributed in a ring along the outer side of the middle forming surface of the upper mold 2. The top plate 21 is used to demold the molded product, so the top plate 21 must have partial contact with the molded product. Therefore, at least part of the molded product is formed on the bottom of the top plate 21, that is, part of the top plate 21 forms the forming surface of the upper mold 2.

[0048] Reference Figure 2as well as Figure 8 As shown, the middle forming surface of the upper mold 2 has a forming convex surface that forms the inner buckle structure of the paper cup.

[0049] A locking structure is also provided between the top plate 21 and the upper mold 2. The locking structure has two states: in the locked state, the top plate 21 and the upper mold 2 are in close contact and locked together, and the top plate 21 does not have a tendency to move away from the upper mold 2 under the action of the ejector spring 22.

[0050] In the unlocked state, the top plate 21 is disengaged from the upper mold 2, and the top plate 21 tends to move away from the upper mold 2 under the action of the ejector spring 22.

[0051] The locking structure is configured to be in a locked state after the upper mold 2 separates from the suction mold 4;

[0052] During the process from when the upper mold 2 and the lower hot-pressing mold 3 are closed until they are completely separated, the locking structure remains in the unlocked state.

[0053] Reference Figures 3-6 As shown, the locking structure includes a hook 25 disposed on the top plate 21 and a connecting plate 24 disposed on one side of the hook 25;

[0054] It also includes a hanging plate 26 and a push plate 27 set in the upper mold 2;

[0055] The upper part of the hook 25 is bent toward the side of the hanging plate 26, and the lower part of the hook 25 is rotatably connected to the top plate 21.

[0056] In the locked state, the upper part of the hook 25 is attached to the hanging plate 26, which limits the downward movement of the top plate 21.

[0057] In the unlocked state, hook 25 is detached from hanging plate 26.

[0058] A return spring is horizontally connected between the connecting plate 24 and the hook 25. The return spring causes the upper part of the hook 25 to tend to swing toward the side of the hanging plate 26.

[0059] The push plate 27 is slidably connected to the upper mold 2 and can slide along the horizontal direction. The push plate 27 can push open the hook 25 mounted on the hanging plate 26, so that the locking structure switches from the locked state to the unlocked state.

[0060] The "disengagement" mentioned above in the unlocked state does not mean that hook 25 and mounting plate 26 are completely out of contact. (See reference...) Figures 3-6As shown in any of the figures, the hanging plate 26 has a vertically extending structure. In the locked state, the upper curved portion of the hook 25 is attached to the upper end of the hanging plate 26. It is worth noting that the vertical length of the hanging plate 26 should be greater than or equal to the maximum distance between the top plate 21 and the upper mold 2, in order to prevent the hook 25 from swinging to a position away from the back of the hanging plate 26 under the action of the return spring.

[0061] Reference Figure 4 As shown, the suction mold 4 is provided with a first guide block 31, and a first guide groove is provided on the first guide block 31. When the upper mold 2 closes with the suction mold 4 downwards, the guide shaft 28 on the push plate 27 is accommodated in the first guide groove. When the upper mold 2 separates from the suction mold 4, the first guide groove guides the push plate 27 to slide away from the hook 25.

[0062] Reference Figure 3 As shown, the hot-pressing lower mold 3 is provided with a second guide block 51, and a second guide groove is provided on the second guide block 51. When the upper mold 2 closes with the hot-pressing lower mold 3 downwards, the guide shaft 28 on the push plate 27 is accommodated in the second guide groove. When the upper mold 2 separates from the suction lower mold 4, the first guide groove guides the push plate 27 to slide toward the hook 25.

[0063] The working steps of the mold disclosed in this embodiment are as follows:

[0064] In the initial state, the locking structure is unlocked, and the top plate 21 and the upper mold 2 are separated to their maximum distance, supported by the limit screw 23. The push plate 27 is in the unlocked state and is closest to the hanging plate 26, but this position does not obstruct the hook 25 from being attached. This position is considered the initial position of the push plate 27.

[0065] The lower mold 4 has a cavity, and the pulp from the pulp tank is drawn into the cavity through the bottom pipe 6 by vacuuming. Then, it is raised by a lifting mechanism and removed from the surface of the pulp tank.

[0066] The upper mold 2 moves to the upper part of the suction mold 4 and closes downward. During the mold closing process, the push plate 27 moves away from the hook 25 under the action of the first guide block 41. At this time, the top plate 21 and the upper mold 2 are pressed together. The hook 25 is hung on the hanging plate 26 under the action of the return spring, so that the locking structure is in the locked state.

[0067] After the upper mold 2 and the lower mold 4 are closed, the upper mold 2 draws air upward and the lower mold 4 blows air upward, thus forming a wet pulp blank in the cavity after the upper mold 2 and the lower mold 4 are closed. The upper mold 2 and the lower mold 4 are separated. During the separation, the upper mold 2 always continues to draw air to fix the wet pulp blank.

[0068] Reference Figure 4 as well as Figure 5As shown, when the upper mold 2 separates from the lower mold 4, the push plate 27 slides toward the hook 25 under the guidance of the first guide groove. When the lower mold 2 is completely separated from the lower mold 4, the push plate 27 does not push the hook 25. At this time, the push plate 27 is in the initial position and the locking structure is in the locked state to prevent the top plate 21 from pushing out the wet pulp blank.

[0069] Next, the upper mold 2 moves to the upper part of the hot-pressing lower mold 3 and closes downward. During the mold closing process, the push plate 27 moves toward the hook 25 under the action of the second guide block 31. After the mold closing is completed, since the push plate 27 always stays close to the side of the hook 25, the swing of the hook 25 toward the hanging plate 26 is limited, so the locking structure always stays in the unlocked state.

[0070] After the upper mold 2 and the hot-pressing lower mold 3 are closed, the moisture of the wet pulp blank is evaporated by heating to form the finished product. The upper mold 2 and the hot-pressing lower mold 3 are separated. During the separation process, the top plate 21 pushes the finished product downward and separates it from the upper mold 2 under the action of the top spring 22.

[0071] Furthermore, during the separation process, the push plate 27 maintains its blocking and limiting effect on the hook 25. Because the top plate 21 moves downwards, the hook 25 and the hanging plate 26 are misaligned. Even if the push plate 27 moves away from the hook 25 under the action of the second guide block 21, the hook 25 cannot be hooked onto the hanging plate 26 under the action of the return spring. This keeps the locking structure in an unlocked state. In other words, during this process, the push plate 27 pushes the hook 25 away, the top plate 21 unlocks and is ejected under the action of the ejector spring, and then, after being squeezed by the mold closing, it re-fits the upper mold. However, because the push plate 27 occupies the space on the side of the hanging plate 26 opposite to the hook 25, the hook 25 cannot be re-hooked onto the hanging plate 26 under the action of the return spring. Figure 6 The state shown.

[0072] After the upper mold 2 and the hot-pressing lower mold 3 are closed, the moisture of the wet pulp blank is evaporated by heating to form the finished product. The upper mold 2 and the hot-pressing lower mold 3 are separated. During the separation process, since the locking structure is in the unlocked state, the top plate 21 pushes the finished product downward and separates it from the upper mold 2 under the action of the top spring 22.

[0073] Furthermore, during the separation process, the push plate 27 maintains its blocking and limiting effect on the hook 25. Because the top plate 21 moves downwards, the positions of the hook 25 and the hanging plate 26 are staggered. Even if the push plate 27 moves away from the hook 25 under the action of the second guide block 21, the hook 25 cannot be hooked onto the hanging plate 26 under the action of the return spring. This keeps the locking structure in the unlocked state. During its ascent, the push plate 27, guided by the second guide block 21, returns to its initial position, and the locking structure remains in its unlocked initial state.

[0074] Although embodiments of the present invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the present invention, the scope of which is defined by the appended claims and their equivalents.

Claims

1. A forced demolding structure for paper-plastic molds, characterized in that: The forced demolding structure is installed on the upper mold (2), including a top plate (21), an ejector spring (22) and a limiting screw (23). The top plate (21) is located at the bottom of the upper mold (2). The ejector spring (22) and the limiting screw (23) are both vertically arranged. One end of the limiting screw (23) is fixedly connected to the top plate (21), and the other end of the limiting screw (23) is slidably connected to the slide groove in the upper mold (2). A limiting surface is provided at the end of the slide groove to limit the height of the limiting screw (23) sliding down. At least part of the top plate (21) forms the forming surface of the upper mold (2); A locking structure is also provided between the top plate (21) and the upper mold (2). The locking structure has two states: in the locked state, the top plate (21) and the upper mold (2) are in contact with each other and locked, and the top plate (21) does not have a tendency to move away from the upper mold (2) under the action of the ejector spring (22). In the unlocked state, the top plate (21) is disengaged from the upper mold (2), and the top plate (21) tends to move away from the upper mold (2) under the action of the ejector spring (22); The forced demolding structure is the part installed on the lower mold, including a guide block, which is used to switch between the two states of the locking structure.

2. The forced demolding structure for paper-plastic molds according to claim 1, characterized in that: The upper mold's forming surface consists of a central forming surface and an edge forming surface, with the edge forming surface located on the top plate (21).

3. The forced demolding structure for paper-plastic molds according to claim 2, characterized in that: The top plate (21) is distributed in a ring along the outer side of the middle forming surface of the upper mold (2), and the middle forming surface of the upper mold (2) has a forming convex surface that forms the inner buckle structure of the paper cup.

4. The forced demolding structure for paper-plastic molds according to claim 1, characterized in that: The locking structure includes a hook (25) provided on the top plate (21) and a connecting plate (24) provided on one side of the hook (25); It also includes a hanging plate (26) and a push plate (27) set in the upper mold (2); The upper part of the hook (25) is bent toward the side of the hanging plate (26), and the lower part of the hook (25) is rotatably connected to the top plate (21); In the locked state, the upper part of the hook (25) is attached to the hanging plate (26), which limits the downward movement of the top plate (21); In the unlocked state, the hook (25) is detached from the mounting plate (26).

5. The forced demolding structure for paper-plastic molds according to claim 4, characterized in that: A return spring is horizontally connected between the connecting plate (24) and the hook (25), and the return spring causes the upper part of the hook (25) to tend to swing toward the side of the hanging plate (26); The push plate (27) is slidably connected to the upper mold (2) and can slide along the horizontal direction. The push plate (27) can push open the hook (25) mounted on the hanging plate (26), so that the locking structure switches from the locked state to the unlocked state.

6. The forced demolding structure for paper-plastic molds according to claim 1, characterized in that: The hanging plate (26) is set in the vertical direction. The upper end of the hanging plate (26) is used to connect with the hook (25). The length of the hanging plate (26) is greater than or equal to the maximum distance of the top plate (21) separated from the upper mold.

7. The forced demolding structure for paper-plastic molds according to claim 1, characterized in that: The suction mold (4) is provided with a first guide block (31), and a first guide groove is provided on the first guide block (31). When the upper mold (2) closes with the suction mold (4) downwards, the guide shaft (28) on the push plate (27) is housed in the first guide groove. When the upper mold (2) separates from the suction mold (4), the first guide groove guides the push plate (27) to slide away from the hook (25).

8. A forced demolding structure for paper-plastic molds according to claim 1 or 7, characterized in that: The hot press lower mold (3) is provided with a second guide block (51), and a second guide groove is provided on the second guide block (51). When the upper mold (2) closes with the hot press lower mold (3) downwards, the guide shaft (28) on the push plate (27) is housed in the second guide groove. When the upper mold (2) separates from the suction lower mold (4), the first guide groove guides the push plate (27) to slide toward the hook (25).

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