Manufacturing method of one-time injection-molded dual-density insole for shoes

Abstract

The invention belongs to the technical field of shoe insole forming, and particularly discloses a manufacturing method of a one-time injection-molded dual-density insole for shoes, which comprises the following steps: S1, mounting a parting strip: positioning and clamping the parting strip into a groove of a lower mold; s2, mold closing and material injection: the upper mold and the lower mold are closed, the interior of the mold is partitioned by a partition strip to form a front sole cavity and a rear foot cavity, a soft material is injected into the front sole cavity by using an injection molding machine, meanwhile, a hard material is injected into the rear foot cavity, and the hard material and the soft material are fused through the partition strip; s3, cooling and curing: cooling the mold, so that the hard material, the soft material and the parting strips are cooled to jointly form a shoe insole with the front sole softer than the rear sole; s4, demolding: opening the mold and taking out the insole. According to the double-density insole injection mold, the interior of the mold is divided into the two cavities through the division bar, material mixing between different materials is prevented, the two materials are injected at a time, the hard material and the soft material are fused through the division bar, the double-density insole is formed, the cost is saved, and the production efficiency is improved.

Description

Technical Field

[0001] The invention belongs to the technical field of shoe midsole molding, and in particular relates to a method for manufacturing a double-density midsole for shoes through one-time injection molding. Background Art

[0002] In the shoemaking industry, the performance of the midsole is directly related to the comfort and durability of the shoe. Especially for high-heeled shoes, in order to meet the wearer's needs for soft and comfortable forefoot and stable heel support, the design of the midsole often requires the use of materials of different hardness in different areas.

[0003] Most existing shoe midsole molding processes use segmented injection molding, that is, first injecting a harder material into a mold cavity, and then replacing the mold or injecting a softer material into another separate area of ​​the same mold after it solidifies. Although this method can achieve the combination of soft and hard materials to a certain extent, it has many shortcomings.

[0004] First, the mold design in the existing process is complex, requiring multiple opening and closing of the mold, replacement of injection molding materials, and multiple injection molding, which not only increases production costs, but also reduces production efficiency. Secondly, due to the fluidity of the material during the injection molding process, even if a partition structure is convexly set in the mold (the partition structure is part of the mold and will not be integrated with the soft and hard materials. After molding, a groove will be formed at the bottom of the shoe midsole), so that the front and rear ends of the mold cavity are partially connected, it is difficult to completely avoid the "material cross-linking" phenomenon between the soft and hard materials, resulting in uneven performance of the finished shoe midsole, affecting the wearing experience.

[0005] Therefore, the inventor is committed to designing a shoe midsole injection molding process to solve the above problems. Summary of the invention

[0006] The purpose of the present invention is to provide a method for manufacturing a dual-density midsole for shoes by one-time injection molding, which can be molded in one shot, save costs, improve production efficiency, and at the same time prevent "material cross-linking" between different materials to make the performance of the shoe midsole uniform.

[0007] In order to achieve the above object, a technical solution adopted by the present invention is:

[0008] A method for manufacturing a dual-density midsole for a shoe by one-time injection molding, comprising the following steps:

[0009] S1. Install the spacer: Position the spacer into the groove of the lower mold so that the spacer separates the space above the bottom cloth in the groove into two parts, front and back;

[0010] S2. Mold closing and material injection: The upper mold and the lower mold are closed, and the interior of the mold is separated by a spacer to form a forefoot cavity and a rear foot cavity. The soft material is injected into the forefoot cavity by an injection molding machine, and the hard material is injected into the rear foot cavity at the same time, so that the hard material and the soft material are fused through the spacer;

[0011] S3, cooling and solidification: cooling the mold so that the hard material, the soft material and the spacer are cooled to form a shoe midsole with the forefoot being softer than the rear foot;

[0012] S4, demoulding: open the upper mold and take out the molded shoe midsole.

[0013] As an improvement of the method for manufacturing a dual-density midsole for shoes by one-time injection molding of the present invention, the method comprises the following steps:

[0014] S0, prefabricate the spacers by cutting or laser cutting;

[0015] S01. Placing the bottom cloth: placing the bottom cloth into the groove of the lower mold, using the positioning column at the bottom of the groove to pass through the bottom cloth, positioning the bottom cloth, and pressing the bottom cloth to make the bottom cloth fit the bottom of the groove of the lower mold;

[0016] S1. Install the spacer: Position the spacer into the groove of the lower mold so that the spacer separates the space above the bottom cloth in the groove into two parts, front and back;

[0017] S11, placing the top layer of fabric; placing the top layer of fabric on the upper mold at a position opposite to the groove, installing a pressure strip, and using the pressure strip to press the top layer of fabric onto the upper mold;

[0018] S2. Mold closing and material injection: The upper mold and the lower mold are closed, and the interior of the mold is separated by a spacer to form a forefoot cavity and a rear foot cavity. The soft material is injected into the forefoot cavity by an injection molding machine, and the hard material is injected into the rear foot cavity at the same time, so that the hard material and the soft material are fused through the spacer;

[0019] S3, cooling and solidification: cooling the mold, so that the hard material, soft material, spacer, bottom cloth and top cloth are cooled to form a shoe midsole with a forefoot being softer than the rear foot;

[0020] S4, demoulding: open the upper mold and take out the molded shoe midsole.

[0021] As an improvement of the method for manufacturing a dual-density midsole for shoes by one-time injection molding of the present invention, step S1 is specifically: placing a spacer into the groove of the lower mold so that the bottom of the spacer presses against the bottom cloth, positioning the spacer using a positioning column, and the two ends of the spacer are respectively inserted into the grooves on the two side walls of the groove, so that the spacer separates the space above the bottom cloth in the groove into two front and rear parts.

[0022] As an improvement of the method for manufacturing a dual-density midsole for shoes by one-time injection molding of the present invention, the number of the positioning posts is multiple pairs, the spacer is clamped between the same pair of the positioning posts, and the spacer is arc-shaped.

[0023] As an improvement of the method for manufacturing a dual-density midsole for shoes by one-time injection molding of the present invention, in step S11, the soft material pouring hole of the upper mold is exposed to the top layer cloth, and the hard material pouring hole of the upper mold is exposed to the pressure strip.

[0024] As an improvement of the method for manufacturing a dual-density midsole for shoes by one-time injection molding of the present invention, the mating surface of the upper mold and the mating surface of the lower mold are both arc-shaped, and the depth of the groove gradually increases from front to back.

[0025] As an improvement of the method for manufacturing a dual-density midsole for shoes by one-time injection molding of the present invention, the hard material is at least one of PP material, ABS material or TPR material, the soft material is at least one of TPE material, TPU material or TPR material, and the spacer is a fiber strip or a TPE strip or a plastic strip or a thermoplastic elastomer strip.

[0026] As an improvement on the method for manufacturing a dual-density midsole by one-time injection molding for shoes of the present invention, the midsole includes a soft material layer, a hard material layer and a spacer. The soft material layer is made of soft material to form the forefoot, and the hard material layer is made of hard material to form the rear foot. The spacer is arc-shaped and is located at the arch of the rear foot, separating the soft material layer and the hard material layer and fusing them together.

[0027] As an improvement on the method for manufacturing a dual-density midsole by one-time injection molding for shoes of the present invention, the shoe midsole also includes a layering strip, a top layer of cloth and a bottom layer of cloth, the top layer of cloth covers the top surfaces of the soft material layer, the spacer strip and the hard material layer, the layering strip is embedded in the bottom of the hard material layer, and the bottom layer of cloth covers the bottom surfaces of the soft material layer, the spacer strip, the hard material layer and the layering strip.

[0028] As an improvement on the method for producing a dual-density midsole by one-time injection molding for shoes of the present invention, two grooves are provided on the mold surface of the lower mold, and a plurality of pairs of positioning columns are vertically provided on the bottom of each of the grooves. A clamping groove for clamping a spacer is provided on two opposite inner walls of each of the grooves. The upper mold and the lower mold are combined to form two mold cavities, and a hard material gate and a soft material gate are provided on the upper mold. The hard material gate is connected to the two mold cavities through two hard material inlet holes, and the soft material gate is connected to the two mold cavities through two soft material inlet holes.

[0029] Compared with the prior art, the method for making a dual-density midsole for shoes by one-time injection molding of the present invention uses spacers to separate the interior of the mold to form a forefoot cavity and a rearfoot cavity, thereby preventing "material cross-talk" between different materials and making the performance of the shoe midsole uniform. Hard material is then injected into the forefoot cavity and soft material is injected into the rearfoot cavity at the same time, and two materials are injected at one time, saving costs and improving production efficiency. The hard material and the soft material are fused together by the spacers, and after cooling and solidification, a dual-density shoe midsole in which the forefoot is softer than the rearfoot can be formed, thereby improving the user's wearing experience. BRIEF DESCRIPTION OF THE DRAWINGS

[0030] Figure 1 is an enlarged schematic cross-sectional view of the shoe midsole of the present invention;

[0031] Figure 2 yes Figure 1 The enlarged view of point A in the middle;

[0032] Figure 3 It is a three-dimensional enlarged schematic diagram of the soft material layer, the hard material layer and the spacer of the present invention;

[0033] Figure 4 It is a three-dimensional structural schematic diagram of the mold of the present invention in an open state;

[0034] Figure 5 It is a schematic diagram of the three-dimensional structure of placing the bottom layer cloth in the lower mold in the present invention;

[0035] Figure 6 It is a three-dimensional structural schematic diagram of the mold after installing the spacer and placing the top layer of cloth in the present invention;

[0036] Figure 7 yes Figure 6 The enlarged view of point B in the middle;

[0037] Figure 8 It is a three-dimensional structural schematic diagram of the mold in the mold closing state in the present invention.

[0038] Illustration Description:

[0039] 1. Hard material layer; 2. Soft material layer; 3. Pressure strip; 4. Bottom material layer; 5. Top material layer; 6. Spacer; 7. Lower mold; 71. Groove; 72. Slot; 73. Positioning column; 8. Upper mold; 81. Hard material inlet hole; 811. Hard material gate; 82. Soft material inlet hole; 821. Soft material gate. DETAILED DESCRIPTION

[0040] The following specifically describes the implementation modes of the present invention in conjunction with the accompanying drawings. The accompanying drawings are only for reference and illustration and do not constitute a limitation on the scope of patent protection of the present invention.

[0041] Reference Figures 1 to 8, a method for manufacturing a dual-density midsole for a shoe by one-time injection molding, comprising the following steps:

[0042] S0, prefabricate the spacers by cutting or laser cutting;

[0043] S01, placing the bottom cloth 4: placing the bottom cloth 4 into the groove 71 of the lower mold 7, using the positioning column 73 at the bottom of the groove 71 to penetrate the bottom cloth 4, positioning the bottom cloth 4, pressing the bottom cloth 4, so that the bottom cloth 4 fits the bottom of the groove 71 of the lower mold 7 (such as Figure 8 shown);

[0044] S1. Install the spacer 6: put the spacer 6 into the groove 71 of the lower mold 7, so that the bottom of the spacer 6 presses against the bottom cloth 4, and use the positioning column 73 to position the spacer 6, and the two ends of the spacer 6 are respectively inserted into the grooves 72 on the two side walls of the groove 71, so that the spacer 6 separates the space above the bottom cloth 4 in the groove 71 into two front and rear parts;

[0045] S11, placing the top layer fabric 5; placing the top layer fabric 5 on the upper mold 8 at a position opposite to the groove 71, installing the pressure strip 3, and using the pressure strip 3 to press the top layer fabric 5 onto the upper mold 8;

[0046] S2, mold closing and material injection: the upper mold 8 is closed with the lower mold 7, and the interior of the mold is separated by the partition bar 6 to form a forefoot cavity and a rear foot cavity. The injection molding machine injects soft material into the forefoot cavity, and injects hard material into the rear foot cavity at the same time. Specifically, the injection molding machine injects hard material through the hard material gate 811, and the hard material enters the forefoot cavity through the hard material runner and the hard material inlet hole 81 in turn. At the same time, the injection molding machine injects soft material through the soft material gate 821, and the soft material enters the rear foot cavity through the soft material runner and the soft material inlet hole 82 in turn, until the forefoot cavity and the rear foot cavity are filled with corresponding materials, so that the hard material and the soft material are fused through the partition bar 6;

[0047] S3, cooling and curing: cooling the mold by air cooling, water cooling, etc., so that the hard material, soft material, spacer strip 6, bottom cloth 4 and top cloth 5 are cooled to form a shoe midsole in which the forefoot is softer than the rear foot;

[0048] S4, demoulding: opening the upper mold 8 and taking out the molded shoe midsole;

[0049] S5, finishing treatment: removing the burrs on the edge of the midsole and the redundant parts at both ends of the spacer 6.

[0050] In the present invention, the same set of molds can form two shoe midsoles at one time. In the same groove 71 of the lower mold 7, there are multiple pairs of positioning columns 73, and the spacer 6 is clamped between the same pair of positioning columns 73. The spacer 6 is installed in an arc shape.

[0051] In the step S11 , the soft material pouring hole 82 of the upper mold 8 is exposed on the top layer of the fabric 5 , and the hard material pouring hole 81 of the upper mold 8 is exposed on the pressure strip 3 .

[0052] In the present invention, the mating surfaces of the upper mold 8 and the lower mold 7 are both arc-shaped, and the depth of each groove 71 gradually increases from front to back, so that the thickness of the molded shoe midsole gradually increases from front to back.

[0053] In the present invention, the hard material is at least one of PP material, ABS material or TPR material, and the hard material of the present invention is preferably PP material. The soft material is at least one of TPE material, TPU material or TPR material, and the soft material of the present invention is preferably TPE material. The spacer 6 is a fiber strip or a TPE strip or a plastic strip or a thermoplastic elastomer strip. Other materials that can fuse and connect the hard material and the soft material can also be used. The spacer 6 of the present invention is preferably a fiber strip, such as carbon fiber, glass fiber, aramid fiber, etc. The top layer cloth 5 and the bottom layer cloth 4 are both non-woven fabrics.

[0054] Reference Figures 1 to 3 The present invention utilizes the above-mentioned one-time injection molding dual-density midsole manufacturing method for shoes to prepare the midsole, which includes a soft material layer 2, a hard material layer 1 and a spacer 6. The soft material layer 2 is made of soft material to form the forefoot, and the hard material layer 1 is made of hard material to form the rear foot (the rear foot includes an arch and a heel, the arch is located between the forefoot and the heel, and the forefoot and the heel are connected by the arch). The spacer 6 is arc-shaped and is located at the arch of the rear foot, separating the soft material layer 2 and the hard material layer 1 and fusing them together.

[0055] The shoe midsole also includes a press strip 3, a top layer cloth 5 and a bottom layer cloth 4. The top layer cloth 5 and the bottom layer cloth 4 are both made of non-woven fabrics. The top layer cloth 5 covers the top surface of the soft material layer 2, the spacer strip 6 and the hard material layer 1. The press strip 3 is in the shape of a long strip and is embedded in the bottom of the hard material layer 1. The bottom layer cloth 4 covers the bottom surface of the soft material layer 2, the spacer strip 6, the hard material layer 1 and the press strip 3.

[0056] In the present invention, the overall thickness of the midsole gradually increases from front to back, and the hardness of the forefoot of the midsole is greater than the hardness of the rear foot (that is, the hardness of the hard material layer 1 is greater than the hardness of the soft material layer 2). The hardness of the hard material layer 1 is 55-90 degrees, and the hardness of the soft material layer 2 is 10-110 degrees (measured by a type A Shore hardness tester).

[0057] Reference Figures 4 to 8In the present invention, the mold used in the above-mentioned method for making a double-density midsole for shoes by one-time injection molding comprises an upper mold 8 and a lower mold 7. Two grooves 71 are arranged on the mold surface of the lower mold 7. A plurality of pairs of positioning columns 73 are vertically arranged at the bottom of each groove 71. The plurality of pairs of positioning columns 73 are arranged at intervals. A clamping groove 72 for clamping the spacer 6 is arranged on the two opposite inner walls of each groove 71. When the spacer 6 is positioned by the plurality of pairs of positioning columns 73 and its two ends are respectively clamped in the two clamping grooves 72, the spacer 6 is arc-shaped. The upper mold 8 and the lower mold 7 are combined to form two mold cavities. The two mold cavities can form a pair of shoe midsoles. A hard material gate 811 and a soft material gate 821 are arranged on the upper mold 8. The hard material gate 811 passes through two hard material gates. The pouring holes 81 are respectively connected to the two mold cavities, and the soft material gate 821 is respectively connected to the two mold cavities through the two soft material pouring holes 82. When a partition bar 6 is respectively installed in the two mold cavities, each mold cavity is separated by the corresponding partition bar 6 to form a forefoot cavity and a rear foot cavity. The injection molding machine injects hard material at the hard material gate 811, and the hard material enters the two rear foot cavities respectively through the two hard material pouring holes 81. At the same time, the injection molding machine injects soft material at the soft material gate 821, and the soft material enters the two forefoot cavities respectively through the two soft material pouring holes 82. The hard material in the rear foot cavity can form a hard material layer 1 after cooling and solidification, and the soft material in the forefoot cavity can form a soft material layer 2 after cooling and solidification.

[0058] The method for manufacturing a dual-density midsole for shoes by one-time injection molding of the present invention has the following technical effects:

[0059] (1) By accurately placing the bottom cloth 4 in the groove 71 of the lower mold, a stable base is provided for subsequent material injection, while enhancing the structural strength of the midsole;

[0060] (2) The spacer bar 6 is inserted into the groove 71 of the mold, which not only simplifies the mold structure, but also effectively prevents the problem of soft and hard materials from mixing during the injection molding process through physical isolation;

[0061] (3) Through single injection molding after mold closing, different soft and hard materials are injected into the forefoot cavity and the rear foot cavity at the same time, which greatly improves production efficiency and reduces costs;

[0062] (4) During the cooling process, the spacer 6, the bottom cloth 4, the top cloth 5 and the soft and hard materials are tightly combined to form an integral shoe midsole that not only meets the softness requirements of the forefoot but also has the stability of the heel support.

[0063] In summary, the present invention effectively solves the problems of material cross-linking, low efficiency and loose material bonding in the traditional shoe midsole molding process by optimizing the mold design, innovatively using the spacer 6 and improving the injection molding process, and provides an efficient and high-quality solution for the manufacturing of midsoles for special shoes such as high heels.

[0064] The above disclosure is only a preferred embodiment of the present invention, which cannot be used to limit the scope of protection of the present invention. Therefore, equivalent changes made within the scope of the patent application of the present invention are still within the scope covered by the present invention.

Claims

1. A method for manufacturing a dual-density midsole for shoes by one-time injection molding, characterized in that: The following steps are involved: S1. Install the spacer: Position the spacer into the groove of the lower mold so that the spacer separates the space above the bottom cloth in the groove into two parts, front and back; S2. Mold closing and material injection: The upper mold and the lower mold are closed, and the interior of the mold is separated by a spacer to form a forefoot cavity and a rear foot cavity. The soft material is injected into the forefoot cavity by an injection molding machine, and the hard material is injected into the rear foot cavity at the same time, so that the hard material and the soft material are fused through the spacer; S3, cooling and solidification: cooling the mold so that the hard material, the soft material and the spacer are cooled to form a shoe midsole with the forefoot being softer than the rear foot; S4, demoulding: open the upper mold and take out the molded shoe midsole.

2. The method for manufacturing a dual-density midsole for shoes by one-time injection molding according to claim 1, characterized in that: The following steps are involved: S0, prefabricate the spacers by cutting or laser cutting; S01. Placing the bottom cloth: placing the bottom cloth into the groove of the lower mold, using the positioning column at the bottom of the groove to pass through the bottom cloth, positioning the bottom cloth, and pressing the bottom cloth to make the bottom cloth fit the bottom of the groove of the lower mold; S1. Install the spacer: Position the spacer into the groove of the lower mold so that the spacer separates the space above the bottom cloth in the groove into two parts, front and back; S11, placing the top layer of fabric; placing the top layer of fabric on the upper mold at a position opposite to the groove, installing a pressure strip, and using the pressure strip to press the top layer of fabric onto the upper mold; S2. Mold closing and material injection: The upper mold and the lower mold are closed, and the interior of the mold is separated by a spacer to form a forefoot cavity and a rear foot cavity. The soft material is injected into the forefoot cavity by an injection molding machine, and the hard material is injected into the rear foot cavity at the same time, so that the hard material and the soft material are fused through the spacer; S3, cooling and solidification: cooling the mold, so that the hard material, soft material, spacer, bottom cloth and top cloth are cooled to form a shoe midsole with a forefoot being softer than the rear foot; S4, demoulding: open the upper mold and take out the molded shoe midsole.

3. The method for manufacturing a dual-density midsole for shoes by one-time injection molding according to claim 2, characterized in that: The step S1 specifically includes: placing the spacer into the groove of the lower mold so that the bottom of the spacer presses against the bottom cloth, positioning the spacer using a positioning column, and respectively inserting the two ends of the spacer into the grooves on the two side walls of the groove so that the spacer separates the space above the bottom cloth in the groove into two front and rear parts.

4. The method for manufacturing a dual-density midsole for shoes by one-time injection molding according to claim 3, characterized in that: The number of the positioning posts is a plurality of pairs, and the spacer is clamped between the same pair of the positioning posts, and the spacer is arc-shaped.

5. The method for manufacturing a dual-density midsole for shoes by one-time injection molding according to claim 2, characterized in that: In the step S11, the soft material pouring hole of the upper mold is exposed on the top layer cloth, and the hard material pouring hole of the upper mold is exposed on the pressure strip.

6. The method for manufacturing a dual-density midsole for shoes by one-time injection molding according to claim 1 or 2, characterized in that: The mating surfaces of the upper mold and the lower mold are both arc-shaped, and the depth of the groove gradually increases from front to back.

7. The method for manufacturing a dual-density midsole for shoes by one-time injection molding according to claim 1 or 2, characterized in that: The hard material is at least one of PP material, ABS material or TPR material, the soft material is at least one of TPE material, TPU material or TPR material, and the spacer strip is a fiber strip or a TPE strip or a plastic strip or a thermoplastic elastomer strip.

8. The method for manufacturing a dual-density midsole for shoes by one-time injection molding according to claim 1 or 2, characterized in that: The shoe midsole includes a soft material layer, a hard material layer and a spacer. The soft material layer is made of soft material to form the forefoot, and the hard material layer is made of hard material to form the rear foot. The spacer is arc-shaped and is located at the arch of the rear foot, separating the soft material layer and the hard material layer and fusing them together.

9. The method for manufacturing a dual-density midsole for shoes by one-time injection molding according to claim 8, characterized in that: The shoe midsole also includes a layering strip, a top layer of cloth and a bottom layer of cloth, the top layer of cloth covers the top surfaces of the soft material layer, the spacer strip and the hard material layer, the layering strip is embedded in the bottom of the hard material layer, and the bottom layer of cloth covers the bottom surfaces of the soft material layer, the spacer strip, the hard material layer and the layering strip.

10. The method for manufacturing a dual-density midsole for shoes by one-time injection molding according to claim 1 or 2, characterized in that: The lower mold is provided with two grooves on the mold surface, and a plurality of pairs of positioning columns are vertically provided at the bottom of each groove. The two opposite inner walls of each groove are provided with clamping grooves for clamping the spacer strips. The upper mold and the lower mold are combined to form two mold cavities. The upper mold is provided with a hard material gate and a soft material gate. The hard material gate is connected with the two mold cavities through two hard material inlet holes, and the soft material gate is connected with the two mold cavities through two soft material inlet holes.

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