Multi-color composite supercritical thermoplastic polyurethane foam forming mold structure

Abstract

The utility model relates to a multicolor composite supercritical thermoplastic polyurethane foam forming mold structure, which comprises a lower mold, an upper mold and a lower mold, the upper die is arranged above the lower die and is provided with a die convex part facing the lower die cavity; the middle die is arranged between the upper die and the lower die and is provided with a hollow ring part corresponding to the lower die cavity and the die convex part, the inner ring surface of the hollow ring part is provided with a positioning structure, and the positioning structure is used for positioning a different-color surface part; through the structural design of the mold, foamed finished products with various colors can be obtained in a single foaming forming process, and matching of various colors can be realized without surface modification or secondary processing after foaming forming, so that the production efficiency is effectively improved, and the cost is saved.

Description

Technical Field

[0001] This utility model relates to supercritical thermoplastic polyurethane (TPU) foaming molding molds, and in particular to a multi-color composite supercritical thermoplastic polyurethane (TPU) foaming molding mold structure. Background Technology

[0002] Supercritical TPU (thermoplastic polyurethane) foaming mold is an advanced technology specifically designed for manufacturing lightweight, highly elastic products. This technology primarily utilizes supercritical fluids (such as carbon dioxide or nitrogen) as foaming agents, dissolving them in the TPU material under high pressure. The pressure is then released within the mold, creating a fine, uniform bubble structure within the material. This achieves the goals of weight reduction, enhanced cushioning, and reduced environmental impact.

[0003] Plastic products integrally molded by supercritical TPU foaming molds can be used for sports shoes and casual shoes midsoles, such as cushioning pads, protective gear and yoga mats, medical and assistive devices such as orthopedic insoles and prosthetic pads, and automotive or bicycle components such as seat cushions and seals.

[0004] However, despite the numerous advantages of supercritical TPU foaming technology, it can only produce monochrome items. This is primarily because supercritical fluids need to be dissolved within the TPU under high pressure. Adding particles or pigments of multiple colors may result in uneven distribution, affecting the foaming effect and the consistency of the final product. Furthermore, the solubility and diffusion characteristics of pigments differ in the supercritical state compared to traditional melt mixing. Attempting to mix multiple colors may lead to color layering or unevenness after foaming due to differences in density or affinity.

[0005] Therefore, if plastic products integrally molded using supercritical TPU foaming are to have multiple colors, further processing is required, highlighting the labor-intensive and time-consuming drawbacks. For example, if different colors are desired on the perimeter of a shoe midsole, the injection-molded midsole must be transported elsewhere for dyeing, coating, or color patch bonding, leading to increased production costs. Utility Model Content

[0006] The purpose of this invention is to provide a multi-color composite supercritical thermoplastic polyurethane (TPU) foaming molding mold structure that can solve one of the above problems.

[0007] To achieve the aforementioned objectives, this utility model provides a multi-color composite supercritical thermoplastic polyurethane (TPU) foaming molding mold structure, comprising: a lower mold having a lower mold cavity; an upper mold disposed above the lower mold and having a mold protrusion facing the lower mold cavity; and a middle mold disposed between the upper mold and the lower mold and having a hollow ring portion corresponding to the lower mold cavity and the mold protrusion. The inner ring surface of the hollow ring portion has a positioning structure for positioning a different colored surface part. When the lower mold, the upper mold, and the middle mold are closed, the lower mold cavity, the mold protrusion, and the hollow ring portion together form a closed mold cavity.

[0008] The advantages of this invention are as follows: By incorporating a positioning structure design in the hollow ring of the intermediate mold, the mold can pre-position the discolored surface part within the hollow ring during the foaming process. Subsequently, mold closing and supercritical foaming operations are performed, resulting in a multi-colored composite foamed product with a discolored surface part. Therefore, this invention's mold structure design allows for the production of multi-colored foamed products in a single foaming process, eliminating the need for post-foaming surface finishing or secondary processing to achieve color combinations, such as dyeing, coating, or bonding with other materials. This invention effectively improves production efficiency and saves costs. This multi-colored composite foamed product can be used as a midsole for athletic and casual shoes, but is not limited to these applications; it can also be used for cushioning pads, protective gear, bicycle seats, etc.

[0009] Preferably, the positioning structure is a plane or a groove.

[0010] Preferably, the intermediate mold includes an intermediate mold body and a separable intermediate mold component. The intermediate mold body has a first connecting portion, the separable intermediate mold component has a second connecting portion that connects to or separates from the first connecting portion, and the hollow ring portion.

[0011] Preferably, the first joint portion of the intermediate mold body has a plurality of positioning protrusions, and the second joint portion of the split intermediate mold has a plurality of positioning recesses corresponding to each of the positioning protrusions.

[0012] In addition, to achieve the aforementioned objective, this utility model provides a multi-color composite supercritical thermoplastic polyurethane (TPU) foaming molding mold structure, comprising: a lower mold having a lower mold cavity and a positioning structure disposed in the lower mold cavity, the positioning structure being used to position a different colored surface part; and an upper mold disposed above the lower mold and having a mold protrusion facing the lower mold cavity, wherein when the lower mold and the upper mold are closed, the lower mold cavity and the mold protrusion together form a closed mold cavity.

[0013] The advantages of this invention are as follows: By incorporating a positioning structure design in the lower mold cavity, the mold can pre-position the discolored surface part within this structure during foaming molding. Subsequently, mold closing and supercritical foaming operations are performed, resulting in a multi-colored composite foamed product with a discolored surface part. Therefore, this invention's mold structure design allows for the production of multi-colored foamed products in a single foaming molding process, eliminating the need for post-foaming surface finishing or secondary processing to achieve color combinations, such as dyeing, coating, or bonding with other materials. This invention effectively improves production efficiency and saves costs. This multi-colored composite foamed product can be used as a midsole for athletic and casual shoes, but is not limited to these applications; it can also be used for cushioning pads, protective gear, bicycle seats, etc.

[0014] Preferably, the positioning structure is a plane or a groove.

[0015] Preferably, the lower mold includes a lower mold body and a separable lower mold component. The lower mold body has a first connecting portion, and the separable lower mold component has a second connecting portion that connects to or separates from the first connecting portion and the positioning structure.

[0016] Preferably, the first joint portion of the lower mold body has a plurality of positioning protrusions, and the second joint portion of the separable lower mold part has a plurality of positioning recesses corresponding to each of the positioning protrusions. Attached Figure Description

[0017] Figure 1 This is an exploded perspective view of the first embodiment of the present invention;

[0018] Figure 2 This is a three-dimensional assembly diagram of the first embodiment of this utility model;

[0019] Figure 3A This is a combined cross-sectional view of the first embodiment of the present invention, showing the state of the lower mold, upper mold and middle mold when they are closed;

[0020] Figure 3B yes Figure 3A A magnified view of a portion of the image;

[0021] Figure 3C This is a partial enlarged view of the first embodiment of the present invention, showing that the positioning structure of the middle mold is in a groove state;

[0022] Figure 4A This is a combined cross-sectional view of the first embodiment of the present invention, showing the state of supercritical foaming operation;

[0023] Figure 4B yes Figure 4A A magnified view of a portion of the image;

[0024] Figure 5This is a perspective view of the first embodiment of the present invention, showing the state of the multi-color composite foamed product;

[0025] Figure 6 This is an exploded perspective view of the second embodiment of the present invention;

[0026] Figure 7 This is a perspective view of the second embodiment of the present invention;

[0027] Figure 8A This is a combined cross-sectional view of the second embodiment of the present invention;

[0028] Figure 8B This is an exploded view of the second embodiment of the present invention;

[0029] Figure 9 This is an exploded perspective view of the third embodiment of the present invention;

[0030] Figure 10A This is a combined cross-sectional view of the third embodiment of the present invention, showing the state when the lower mold and the upper mold are closed;

[0031] Figure 10B yes Figure 10A A magnified view of a portion of the image;

[0032] Figure 11 This is an exploded perspective view of the fourth embodiment of the present invention;

[0033] Figure 12 This is a three-dimensional assembly diagram of the fourth embodiment of this utility model;

[0034] Figure 13 This is an exploded view of the fourth embodiment of the present invention; and

[0035] Figure 14 This is a combined cross-sectional view of the fourth embodiment of the present invention.

[0036] In the diagram: 10. Different colored surface part; 11. Different colored surface; 12. Fusion interface layer; 20. Foamed finished product; 30. Lower mold; 31. Lower mold cavity; 311. Positioning structure; 32. Lower mold body; 321. First joint; 322. Positioning protrusion; 33. Separable lower mold part; 331. Second joint; 332. Positioning recess; 40. Upper mold; 41. Mold protrusion; 50. Middle mold; 51. Hollow ring; 511. Positioning structure; 52. Middle mold body; 521. First joint; 522. Positioning protrusion; 53. Separable middle mold part; 531. Second joint; 532. Positioning recess; 60. Guide post; A. Closed mold cavity. Detailed Implementation

[0037] Before this utility model is described in detail, it should be noted that similar parts are represented by the same numbers in the following description.

[0038] See Figures 1 to 3B As shown, the first embodiment of this utility model provides a multi-color composite supercritical thermoplastic polyurethane (TPU) foaming molding mold structure, suitable for providing a different colored surface part 10. The different colored surface part 10 has a different colored surface 11, and the color presented by the different colored surface 11 is different from the color presented by the foamed finished product 20 (e.g., Figure 5 (As shown). The multi-color composite supercritical thermoplastic polyurethane (TPU) foam molding mold structure mainly consists of a lower mold 30, an upper mold 40, and a middle mold 50. In this embodiment, a mold for molding a shoe midsole is taken as an example, but it is not limited thereto.

[0039] The lower mold 30 has a lower mold cavity 31 shaped like a shoe midsole.

[0040] The upper mold 40 is disposed above the lower mold 30 and has a mold protrusion 41 facing the lower mold cavity 31 and shaped like a shoe midsole. In this embodiment, the upper mold 40 is movable back and forth along the guide post 60 toward the lower mold 30.

[0041] The intermediate mold 50 is disposed between the upper mold 40 and the lower mold 30, and has a hollow ring portion 51 corresponding to the lower mold cavity 31 and the mold protrusion 41. The inner ring surface of the hollow ring portion 51 has a positioning structure 511, which is used to position the discolored surface part 10. When the lower mold 30, the upper mold 40 and the intermediate mold 50 are closed, the lower mold cavity 31, the mold protrusion 41 and the hollow ring portion 51 together form a closed mold cavity A. In this embodiment, the intermediate mold 50 can be reciprocally disposed between the lower mold 30 and the upper mold 40 along the guide post 60, but it is not limited thereto. The intermediate mold 50 can also be pivotally disposed on the lower mold 30 at one end, so that the intermediate mold 50 can be opened or closed with the lower mold 30 by means of a lifting motion. In addition, in this embodiment, the positioning structure 511 is planar, allowing the discolored surface member 10 to be positioned on the positioning structure 511 by means of material properties or other properties; however, this is not a limitation, see also [reference needed]. Figure 3C As shown, the positioning structure 511 can also be in the shape of a groove, so that the discolored surface part 10 can be stably positioned on the groove-shaped positioning structure 511.

[0042] It is worth noting that the discolored surface part 10 also has a fusion interface layer 12 opposite to the discolored surface 11. The fusion interface layer 12 is a hot melt polyurethane adhesive, but it is not limited to this. The material of the fusion interface layer 12 can be fused with the TPU material injected during mold closing, so that the foamed finished product 20 and the discolored surface part 10 are integrated.

[0043] The above describes the configuration of the main components of the first embodiment of this utility model. The operation and function of this utility model are explained below.

[0044] See Figure 1 and Figure 3B As shown, by designing a positioning structure 511 in the hollow ring portion 51 of the intermediate mold 50, the mold can pre-position the discolored surface part 10 in the hollow ring portion 51 of the intermediate mold 50 during the foaming molding operation. (See reference...) Figure 3A , Figure 4A , Figure 4B and Figure 5 As shown, the lower mold 30, the upper mold 40 and the middle mold 50 are then closed, and a supercritical foaming operation is performed on the closed mold, so that the foamed product 20 has a different colored surface part 10, so as to present a multi-colored composite foamed product 20.

[0045] Therefore, the mold structure design of this utility model allows for the production of multi-colored foamed products 20 in a single foaming molding process, eliminating the need for post-foaming surface finishing or secondary processing to achieve multiple color combinations, such as dyeing, coating, or bonding with other materials. Thus, this utility model effectively improves production efficiency and saves costs. This multi-colored composite foamed product can be used as the midsole of sports shoes and casual shoes, but is not limited to these applications; it can also be used as cushioning pads for sports equipment, protective gear, bicycle seats, etc.

[0046] See Figures 6 to 8B As shown, the second embodiment of this utility model provides a multi-color composite supercritical thermoplastic polyurethane (TPU) foaming molding mold structure. The difference between the second embodiment and the first embodiment lies in the structural design of the middle mold 50.

[0047] The intermediate mold 50 includes an intermediate mold body 52 and a separable intermediate mold component 53. The intermediate mold body 52 has a first connecting portion 521, and the separable intermediate mold component 53 has a second connecting portion 531 that connects to or separates from the first connecting portion 521, and a hollow ring portion 51. In this embodiment, the first connecting portion 521 is in the form of a groove, and the second connecting portion 531 is in the form of a protrusion. The first connecting portion 521 of the intermediate mold body 52 has a plurality of positioning protrusions 522, and the second connecting portion 531 of the separable intermediate mold component 53 has a plurality of positioning recesses 532 corresponding to each positioning protrusion 522. When the separable intermediate mold component 53 is connected to the intermediate mold body 52, the positioning recesses 532 fit over the positioning protrusions 522, thereby improving the accuracy and stability of the connection between the separable intermediate mold component 53 and the intermediate mold body 52.

[0048] By adopting a split structure design of the intermediate mold 50, which combines the intermediate mold body 52 with the split intermediate mold parts 53, one intermediate mold body 52 can be used with multiple split intermediate mold parts 53. Accordingly, when the split intermediate mold part 53 is being injection molded, another spare split intermediate mold part 53 can be installed with the different colored surface part 10 simultaneously outside the production line. In this way, after the injection operation of the current split intermediate mold part 53 is completed, it can be immediately replaced and the split intermediate mold part 53 with the different colored surface part 10 installed can continue to be put into production. This not only saves the waiting time for the split intermediate mold part 53 to cool or clean, but also avoids the idleness of the production line.

[0049] Furthermore, the replaced split-type mold part 53 can be sent to the pre-processing area immediately for the installation of the discolored surface part 10, completing the preparation work for the next round, forming a continuous cyclical production process with alternating pre-processing and injection operations. Therefore, the structural design of the second embodiment of this utility model realizes the parallelization of the mold processing flow, greatly improving the overall production efficiency. It is particularly suitable for multi-cavity, high-volume injection processes, helping to shorten the production cycle, increase equipment utilization, thereby reducing production costs and enhancing market competitiveness.

[0050] See Figures 9 to 10B As shown, the third embodiment of this utility model provides a multi-color composite supercritical thermoplastic polyurethane (TPU) foaming molding mold structure. The difference between this third embodiment and the first embodiment is that the multi-color composite supercritical thermoplastic polyurethane (TPU) foaming molding mold structure mainly consists of a lower mold 30 and an upper mold 40. In this embodiment, a bicycle saddle is used as an example, but it is not limited to this; it can also be used to mold cushioning pads and protective gear for sports equipment. Wherein:

[0051] The lower mold 30 has a lower mold cavity 31 in the shape of a bicycle seat and a positioning structure 311 disposed in the lower mold cavity 31. The positioning structure 311 is used to position a different colored surface part 10. The material and structural form of the different colored surface part 10 are the same as those in the first embodiment, except that it is in the shape of a seat.

[0052] The upper mold 40 is disposed above the lower mold 30 and has a mold protrusion 41 shaped like a bicycle seat facing the lower mold cavity 31. When the lower mold 30 and the upper mold 40 are closed, the lower mold cavity 31 and the mold protrusion 41 together form a closed mold cavity A. In this embodiment, the upper mold 40 can be reciprocated along the guide post 60 toward the lower mold 30.

[0053] By designing a positioning structure 311 in the lower mold cavity 31 of the lower mold 30, the mold can pre-position the discolored surface part 10 in the positioning structure 311 of the lower mold 30 during the foaming molding operation. Then, the mold is closed and supercritical foaming operation is performed, so that the foamed product 20 has the discolored surface part 10, thus presenting a multi-colored composite foamed product 20. It can be seen that the mold structure design of this utility model can obtain a foamed product 20 with multiple colors in a single foaming molding process, without the need for surface modification or secondary processing after foaming molding to achieve the combination of multiple colors, such as dyeing, coating or bonding with other materials. Therefore, this utility model effectively improves production efficiency and saves costs.

[0054] See Figures 11 to 14 As shown, the fourth embodiment of this utility model provides a multi-color composite supercritical thermoplastic polyurethane (TPU) foaming molding mold structure. The difference between the fourth embodiment and the third embodiment lies in the structural design of the lower mold 30.

[0055] The lower mold 30 includes a lower mold body 32 and a separable lower mold component 33. The lower mold body 32 has a first connecting portion 321, and the separable lower mold component 33 has a second connecting portion 331 that connects to or separates from the first connecting portion 321, a lower mold cavity 31, and a positioning structure 311. In this embodiment, the first connecting portion 321 of the lower mold body 32 is in the shape of a groove and has a plurality of positioning protrusions 322, and the second connecting portion 331 of the separable lower mold component 33 is in the shape of a protrusion and has a plurality of positioning recesses 332 corresponding to each positioning protrusion 322. When the separable lower mold component 33 is connected to the lower mold body 32, the positioning recesses 332 fit over the positioning protrusions 322 to improve the accuracy and stability of the connection between the two.

[0056] Since the split structure design adopted by the lower mold 30 has the same effects as the description of the split middle mold 50 in the second embodiment, it will not be repeated here.

Claims

1. A multi-color composite supercritical thermoplastic polyurethane foam molding mold structure, characterized in that, include: One mold has one mold cavity; An upper mold is disposed above the lower mold and has a mold protrusion facing the lower mold cavity; as well as A middle mold is disposed between the upper mold and the lower mold, and has a hollow ring portion corresponding to the lower mold cavity and the mold protrusion. The inner ring surface of the hollow ring portion has a positioning structure for positioning a different colored surface part. When the lower mold, the upper mold and the middle mold are closed, the lower mold cavity, the mold protrusion and the hollow ring portion together form a closed mold cavity.

2. The multi-color composite supercritical thermoplastic polyurethane foam molding die structure as described in claim 1, characterized in that, The positioning structure can be a plane or a groove.

3. The multi-color composite supercritical thermoplastic polyurethane foam molding die structure as described in claim 1, characterized in that, The intermediate mold includes an intermediate mold body and a separable intermediate mold component. The intermediate mold body has a first connecting portion, the separable intermediate mold component has a second connecting portion that connects with or separates from the first connecting portion, and a hollow ring portion.

4. The multi-color composite supercritical thermoplastic polyurethane foam molding die structure as described in claim 3, characterized in that, The first joint of the middle mold body has a plurality of positioning protrusions, and the second joint of the split middle mold has a plurality of positioning recesses corresponding to each of the positioning protrusions.

5. A multi-color composite supercritical thermoplastic polyurethane foam molding die structure, characterized in that, include: A lower mold has a lower mold cavity and a positioning structure disposed in the lower mold cavity, the positioning structure being used to position a part with a different colored surface; as well as An upper mold is disposed above the lower mold and has a mold protrusion facing the lower mold cavity. When the lower mold and the upper mold are closed, the lower mold cavity and the mold protrusion together form a closed mold cavity.

6. The multi-color composite supercritical thermoplastic polyurethane foam molding die structure as described in claim 5, characterized in that, The positioning structure can be a plane or a groove.

7. The multi-color composite supercritical thermoplastic polyurethane foam molding die structure as described in claim 5, characterized in that, The lower mold includes a lower mold body and a separable lower mold component. The lower mold body has a first connecting portion, and the separable lower mold component has a second connecting portion that connects with or separates from the first connecting portion, as well as the positioning structure.

8. The multi-color composite supercritical thermoplastic polyurethane foam molding die structure as described in claim 7, characterized in that, The first joint of the lower mold body has a plurality of positioning protrusions, and the second joint of the split lower mold part has a plurality of positioning recesses corresponding to each of the positioning protrusions.

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