Footwear dual-density insole and production process and mold thereof

Abstract

The invention provides a shoe dual-density insole and a production process and mold thereof, the insole comprises a hard plastic half fork, a soft plastic half sole and a plastic strip, and the hard plastic half fork, the soft plastic half sole and the plastic strip are integrally formed. A shoe dual-density insole mold comprises an upper mold and a lower mold, a cavity used for containing foaming materials is formed between the bottom face of the upper mold and the upper surface of the lower mold, a plastic strip positioning pin is arranged in the middle of the lower mold, and the plastic strip positioning pin is used for fixing a plastic strip in the middle of the lower mold. And a foaming particle feeding hole is formed in the upper surface of the upper mold. The soft material and hard material combined dual-density insole is produced, the rear-end sole part is hard and plays a supporting role, the front-end sole part is soft, the sole is comfortable to wear, one-time injection molding of the soft material and the hard material is achieved through the production process, the tedious process of injection molding in two times is avoided, and the production efficiency is improved. Therefore, the production efficiency is improved, and the cost is reduced.

Description

Technical Field

[0001] The invention relates to the technical field of sole structures, and in particular to a double-density midsole of footwear and a production process and a mold thereof. Background Art

[0002] A pair of high-quality high-heeled shoes can make women more beautiful and confident, but the price of beauty is that the feet need to withstand a large front-to-back drop. The soles of conventional high-heeled shoes are integrally formed with the heels. Due to the large front-to-back drop, a material with higher hardness is needed to support the user's metatarsal bones. However, the hard soles of high-heeled shoes have poor shock absorption ability, and the user's feet are in a tense state and cannot effectively buffer the impact when walking, so the user will quickly feel tired. The existing solution is to use softer insoles to minimize the impact, but the thickness of the insoles is still not enough to offset the impact generated when walking, and they are easy to slide in the shoes, which is not conducive to the user's walking.

[0003] The human foot is divided into the forefoot, the outer side of the sole, the heel and the arch. The Yongquan point is located in the depression of the forefoot when the foot is curled, approximately at the intersection of the front 1 / 3 and the back 2 / 3 of the line connecting the tips of the second and third toes and the heel. The point of force when wearing high heels is within a certain range forward of the Yongquan point.

[0004] When standing in high heels, 60% of the body weight needs to be supported by the forefoot, especially for high heels with 8 cm long heels, where almost all of the body weight is supported by the forefoot; when walking in high heels, the force application position of the foot changes from the heel dissipating force and the forefoot applying force to the forefoot both dissipating force and applying force. At the moment the foot contacts the ground, the reaction force of the ground changes the downward component of the force into an upward component of force, and the forefoot will bear double the pressure, so the forefoot is prone to soreness and pain.

[0005] There is a double-density sole with a soft front and hard back. The double-density sole mold used in production solves the problem of producing a sole with a soft upper surface and a hard lower surface. However, the existing technology requires two injection moldings to complete the production of the sole, which is troublesome to operate and leads to low output.

[0006] A new type of dual-density midsole for footwear and its production process and mold are now needed to solve the above-mentioned problems. Summary of the invention

[0007] The invention provides a double-density midsole for shoes, a production process and a mold thereof, and solves the problem that the existing double-density midsole needs to be injected twice, the production process is relatively complicated and the production efficiency is low by technically transforming the existing high-heeled shoe midsole production process.

[0008] To achieve the above object, the technical solution adopted by the present invention is:

[0009] A double-density midsole for footwear comprises a hard plastic half fork, a soft plastic forefoot and a plastic strip, wherein the plastic strip divides the midsole into a front end area and a rear end area, wherein the rear end area is the hard plastic half fork, and the front end area is the soft plastic forefoot, and the hard plastic half fork, the soft plastic forefoot and the plastic strip are integrally formed.

[0010] A double-density midsole mold for shoes comprises an upper mold and a lower mold, wherein a cavity for accommodating a foaming material is formed between the bottom surface of the upper mold and the upper surface of the lower mold, a plastic strip positioning pin is arranged in the middle position of the lower mold, and the plastic strip positioning pin is used to fix the plastic strip in the middle position of the lower mold, and the plastic strip divides the cavity into a front end cavity and a rear end cavity, and a foaming particle feeding port is provided on the upper surface of the upper mold.

[0011] Preferably, the foamed particle feed port includes a soft material feed port and a hard material feed port, the soft material feed port is connected to the front end chamber of the internal cavity of the mold, the hard material feed port is connected to the rear end chamber of the internal cavity of the mold, and the soft material feed port and the hard material feed port are connected to an external injection machine.

[0012] Preferably, the plastic strip positioning pins include an upper positioning pin and a lower positioning pin, the upper positioning pin and the lower positioning pin are respectively fixedly arranged on the upper and lower sides of the middle position of the lower mold, and the plastic strip is clamped between the upper positioning pin and the lower positioning pin.

[0013] Preferably, a gap is formed between the upper end surface of the plastic strip and the upper mold.

[0014] A production process for a dual-density midsole for footwear, comprising the following steps:

[0015] S1. Material preparation and pretreatment: Select appropriate soft and hard materials to ensure that their physical and chemical properties are stable and can meet the requirements of high-heeled shoes for cushioning, support and wear resistance. Pre-treat soft and hard materials, such as drying and screening, to ensure uniform quality of materials and avoid defects in the production process.

[0016] S2. Mold design and production. According to the design requirements of the midsole of high-heeled shoes, a dual-density mold is designed and produced. A plastic strip should be set in the mold to divide the mold cavity into two parts, the front end and the rear end. The mold should have two independent injection holes, corresponding to the front end and the rear end, so that soft and hard materials can be injected at the same time to ensure the accuracy and durability of the mold, so as to improve production efficiency and product quality;

[0017] S3, molding process, use a double-head injection machine to inject the soft material and hard material into the front and rear ends of the mold through the injection holes respectively, control the injection speed, pressure and time to ensure that the soft material and hard material can fully fill the mold and achieve the desired shape. During the injection molding process, pay attention to controlling environmental factors such as temperature and humidity to avoid adverse reactions of the material in the mold;

[0018] S4, cooling and demoulding, a cooling system is set in the mold to quickly cool the molded midsole to shorten the production cycle and improve product quality. After cooling, the mold is opened and the molded midsole is taken out. At this time, the soft material and the hard material should be separated by a plastic strip, and the three are hot-melt-molded into one;

[0019] S5. Subsequent processing and quality inspection: the removed midsole shall be polished, trimmed and decorated as necessary to improve its appearance quality and wearing comfort. Strict quality inspection shall be carried out to ensure that the midsole meets the design requirements and quality standards. Unqualified products shall be reworked or scrapped.

[0020] The beneficial effects of the present invention are:

[0021] The present invention adopts two materials of different densities to foam and form shoes of different densities before and after, and then a plastic strip is arranged in the midsole manufacturing mold, and the soft material and the hard material are spaced apart, and the soft material and the hard material are respectively injected into the front end and the rear end of the mold cavity at the same time, and the soft material and the hard material are spaced apart by the plastic strip. During the foaming molding process, the soft material and the hard material wrap the plastic strip to form an integrated structure, the sole part formed by the rear end cavity is harder than the sole part formed by the front end cavity, and plays a supporting role, and the sole part formed by the front end cavity is relatively soft, and the sole is more comfortable to wear.

[0022] This production process realizes one-time injection molding of soft and hard materials, avoiding the cumbersome process of two-step injection molding, thereby improving production efficiency and reducing costs. At the same time, because the soft and hard materials are separated by plastic strips and hot-melt molded in one piece, the midsole has better resistance to bending and deformation and lower risk of breakage. Therefore, this process has significant advantages and broad application prospects in the production of high-heeled shoe midsoles.

[0023] Through the above improved technical solutions, the production process of dual-density midsoles will be more mature and efficient, and can meet the needs of the high-heeled shoe market for comfort and durability. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] Figure 1 It is a schematic diagram of the structure of the midsole product of the present invention;

[0025] Figure 2 It is a schematic diagram of the mold structure of the present invention;

[0026] Figure 3 It is a schematic diagram of the internal structure of the mold of the present invention;

[0027] Figure 4 It is a schematic diagram of the production process steps of the dual-density midsole of the present invention;

[0028] Description of the accompanying drawings: hard plastic half fork 1, soft plastic forefoot 2, plastic strip 3, upper mold 4, lower mold 5, cavity 6, front end chamber 61, rear end chamber 62, plastic strip positioning pin 7, upper side positioning pin 71, lower side positioning pin 72, foam particle feed inlet 8, soft material feed inlet 81, hard material feed inlet 82. DETAILED DESCRIPTION

[0029] The specific contents of the present invention are described in detail below with reference to the accompanying drawings and embodiments.

[0030] See also Figure 1-4 As shown, the present invention provides a dual-density midsole for footwear, comprising a hard plastic half fork 1, a soft plastic forefoot 2 and a plastic strip 3, wherein the plastic strip 3 divides the midsole into a front end area and a rear end area, wherein the rear end area is the hard plastic half fork 1, and the front end area is the soft plastic forefoot 2, and the hard plastic half fork 1, the soft plastic forefoot 2 and the plastic strip 3 are integrally formed.

[0031] The hard plastic half fork 1 is made of environmentally friendly EVA material, and the soft plastic forefoot 2 is made of soft PU material, ensuring that they have excellent cushioning performance and wear resistance.

[0032] A double-density midsole mold for shoes, comprising an upper mold 4 and a lower mold 5, wherein a cavity 6 for accommodating a foaming material is formed between the bottom surface of the upper mold 4 and the upper surface of the lower mold 5, a plastic strip positioning pin 7 is provided in the middle position of the lower mold 5, the plastic strip positioning pin 7 is used to fix the plastic strip 3 in the middle position of the lower mold 5, the plastic strip 3 divides the cavity 6 into a front end chamber 61 and a rear end chamber 62, and a foaming particle feeding port 8 is provided on the upper surface of the upper mold 4.

[0033] Furthermore, in order to achieve the simultaneous injection of soft material and hard material, the foam particle feed port 8 includes a soft material feed port 81 and a hard material feed port 82, the soft material feed port 81 is connected to the front end chamber 61 of the internal cavity 6 of the mold, the hard material feed port 82 is connected to the rear end chamber 62 of the internal cavity 6 of the mold, and the soft material feed port 81 and the hard material feed port 82 are connected to an external injection machine.

[0034] Furthermore, the plastic strip positioning pin 7 includes an upper positioning pin 71 and a lower positioning pin 72, and the upper positioning pin 71 and the lower positioning pin 72 are respectively fixedly arranged on the upper and lower sides of the middle position of the lower mold 5, and the plastic strip 3 is clamped between the upper positioning pin 71 and the lower positioning pin 72.

[0035] Furthermore, in order to enable the soft material and the hard material to be integrally formed with the plastic strip 3 after foaming, a gap is formed between the upper end surface of the plastic strip 3 and the upper mold 4 .

[0036] The production process of the above-mentioned dual-density midsole for footwear comprises the following steps:

[0037] S1. Material preparation and pretreatment: Select appropriate soft and hard materials to ensure that their physical and chemical properties are stable and can meet the requirements of high-heeled shoes for cushioning, support and wear resistance. Pre-treat soft and hard materials, such as drying and screening, to ensure uniform quality of materials and avoid defects in the production process.

[0038] S2. Mold design and production. According to the design requirements of the midsole of high-heeled shoes, a dual-density mold is designed and produced. A plastic strip should be set in the mold to divide the mold cavity into two parts, the front end and the rear end. The mold should have two independent injection holes, corresponding to the front end and the rear end, so that soft and hard materials can be injected at the same time to ensure the accuracy and durability of the mold, so as to improve production efficiency and product quality;

[0039] S3, molding process, use a double-head injection machine to inject the soft material and hard material into the front and rear ends of the mold through the injection holes respectively, control the injection speed, pressure and time to ensure that the soft material and hard material can fully fill the mold and achieve the desired shape. During the injection molding process, pay attention to controlling environmental factors such as temperature and humidity to avoid adverse reactions of the material in the mold;

[0040] S4, cooling and demoulding, a cooling system is set in the mold to quickly cool the molded midsole to shorten the production cycle and improve product quality. After cooling, the mold is opened and the molded midsole is taken out. At this time, the soft material and the hard material should be separated by a plastic strip, and the three are hot-melt-molded into one;

[0041] S5. Subsequent processing and quality inspection: the removed midsole shall be polished, trimmed and decorated as necessary to improve its appearance quality and wearing comfort. Strict quality inspection shall be carried out to ensure that the midsole meets the design requirements and quality standards. Unqualified products shall be reworked or scrapped.

[0042] The present invention adopts two materials of different densities to foam and form shoes of different densities before and after, and then a plastic strip is arranged in the midsole manufacturing mold, and the soft material and the hard material are spaced apart, and the soft material and the hard material are respectively injected into the front end and the rear end of the mold cavity at the same time, and the soft material and the hard material are spaced apart by the plastic strip. During the foaming molding process, the soft material and the hard material wrap the plastic strip to form an integrated structure, the sole part formed by the rear end cavity is harder than the sole part formed by the front end cavity, and plays a supporting role, and the sole part formed by the front end cavity is relatively soft, and the sole is more comfortable to wear.

[0043] This production process realizes one-time injection molding of soft and hard materials, avoiding the cumbersome process of two-step injection molding, thereby improving production efficiency and reducing costs. At the same time, because the soft and hard materials are separated by plastic strips and hot-melt molded in one piece, the midsole has better resistance to bending and deformation and lower risk of breakage. Therefore, this process has significant advantages and broad application prospects in the production of high-heeled shoe midsoles.

[0044] Through the above improved technical solutions, the production process of dual-density midsoles will be more mature and efficient, and can meet the needs of the high-heeled shoe market for comfort and durability.

[0045] Finally, it should be noted that the above embodiments are only used to illustrate the technical solution of the present invention rather than to limit it. Although the present invention has been described in detail with reference to the preferred embodiments, those skilled in the art should understand that the technical solution of the present invention can be modified or replaced by equivalents without departing from the purpose and scope of the technical solution of the present invention, which should be included in the scope of the claims of the present invention.

[0046] The standard parts used in the present invention can all be purchased from the market, and special-shaped parts can be customized according to the description in the specification and the drawings. The specific connection methods of each part adopt conventional means such as mature bolts, rivets, welding, etc. in the prior art. Machinery, parts and equipment all adopt conventional models in the prior art, and the circuit connection adopts the conventional connection method in the prior art, which will not be described in detail here.

[0047] In the description of the present invention, unless otherwise clearly specified and limited, the terms "installed", "connected", "connected", and "fixed" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be directly connected or connected through an intermediate medium, it can be the internal connection of two elements or the interaction relationship between two elements. For those skilled in the art, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

Claims

1. A dual-density midsole for footwear, characterized in that: It includes a hard plastic half fork, a soft plastic forefoot and a plastic strip, wherein the plastic strip divides the midsole into a front end area and a rear end area, wherein the rear end area is the hard plastic half fork, and the front end area is the soft plastic forefoot, and the hard plastic half fork, the soft plastic forefoot and the plastic strip are integrally formed.

2. A dual-density midsole mold for footwear, characterized in that: It includes an upper mold and a lower mold, a cavity for accommodating foaming material is formed between the bottom surface of the upper mold and the upper surface of the lower mold, a plastic strip positioning pin is arranged in the middle position of the lower mold, the plastic strip positioning pin is used to fix the plastic strip in the middle position of the lower mold, the plastic strip divides the cavity into a front end chamber and a rear end chamber, and a foaming particle feeding port is opened on the upper surface of the upper mold.

3. A dual-density midsole mold for footwear according to claim 2, characterized in that: The foam particle feed port includes a soft material feed port and a hard material feed port. The soft material feed port is connected to the front end chamber of the internal cavity of the mold, and the hard material feed port is connected to the rear end chamber of the internal cavity of the mold. The soft material feed port and the hard material feed port are connected to an external injection machine.

4. A dual-density midsole mold for footwear according to claim 2, characterized in that: The plastic strip positioning pins include an upper positioning pin and a lower positioning pin, which are respectively fixedly arranged at the upper and lower sides of the middle position of the lower mold, and the plastic strip is clamped between the upper positioning pin and the lower positioning pin.

5. The dual-density midsole mold for footwear according to claim 2, characterized in that: A gap is formed between the upper end surface of the plastic strip and the upper mold.

6. A production process for a dual-density midsole for footwear, characterized in that: The following steps are involved: S1. Material preparation and pretreatment: Select appropriate soft and hard materials to ensure that their physical and chemical properties are stable and can meet the requirements of high-heeled shoes for cushioning, support and wear resistance. Pre-treat soft and hard materials, such as drying and screening, to ensure uniform quality of materials and avoid defects in the production process. S2. Mold design and production. According to the design requirements of the midsole of high-heeled shoes, a dual-density mold is designed and produced. A plastic strip should be set in the mold to divide the mold cavity into two parts, the front end and the rear end. The mold should have two independent injection holes, corresponding to the front end and the rear end, so that soft and hard materials can be injected at the same time to ensure the accuracy and durability of the mold, so as to improve production efficiency and product quality; S3, molding process, use a double-head injection machine to inject the soft material and hard material into the front and rear ends of the mold through the injection holes respectively, control the injection speed, pressure and time to ensure that the soft material and hard material can fully fill the mold and achieve the desired shape. During the injection molding process, pay attention to controlling environmental factors such as temperature and humidity to avoid adverse reactions of the material in the mold; S4, cooling and demoulding, a cooling system is set in the mold to quickly cool the molded midsole to shorten the production cycle and improve product quality. After cooling, the mold is opened and the molded midsole is taken out. At this time, the soft material and the hard material should be separated by a plastic strip, and the three are hot-melt-molded into one; S5. Subsequent processing and quality inspection: the removed midsole shall be polished, trimmed and decorated as necessary to improve its appearance quality and wearing comfort. Strict quality inspection shall be carried out to ensure that the midsole meets the design requirements and quality standards. Unqualified products shall be reworked or scrapped.

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