Simple mountaineering helmet production process

Abstract

The invention relates to the technical field of mountaineering helmet production processes, in particular to a simple mountaineering helmet production process which comprises the following steps: (1) preparing raw materials including 80-83 parts by weight of foamed polypropylene (EPP); 17 to 20 parts by weight of expanded polystyrene (EPS); 1 to 5 parts by weight of polycarbonate (PC); (2) carrying out EPP main body molding: a) injecting EPP particles into a mold; b) injecting steam, heating and pressurizing to expand and fuse the EPP particles; c) cooling until forming; d) opening the mold and taking out the EPP main body; (3) EPS inner layer forming and PC outer layer forming are conducted, specifically, a, the formed EPP main body and PC are put into an EPS forming mold; b) injecting pre-foamed EPS particles into the inner cavity of the EPP main body; c) injecting steam, heating and pressurizing, so that the EPS particles are expanded and combined with the EPP main body and the PC; d) cooling until forming; and e) opening the mold and taking out a finished product.

Description

Technical Field

[0001] The invention relates to the technical field of mountaineering helmet production technology, in particular to a simple mountaineering helmet production technology. Background Art

[0002] With the increasing popularity of mountaineering, the requirements for the safety performance of mountaineering equipment are also constantly increasing. Among them, mountaineering helmets, as key safety protection equipment, have always been the focus of research and improvement. Traditional mountaineering helmets mainly use expanded polystyrene (EPS) as the main material. This material has good cushioning performance and lightweight characteristics, and performs well in a single strong impact. However, with the increasing complexity of mountaineering activities, helmets with a single material structure have gradually revealed their limitations.

[0003] At present, the most advanced mountaineering helmets on the market usually use EPS as the main structure, covered with a hard plastic shell on the outside. While this design provides basic protection, it also brings some problems. First, although EPS material can effectively absorb the energy of a single impact, its performance will rapidly decline in multiple impacts, and it cannot provide continuous and effective protection for mountaineering activities in long-term and complex environments. Secondly, in order to enhance the overall strength of the helmet, manufacturers often increase the density or thickness of EPS, which inevitably leads to an increase in the weight of the helmet and reduces the wearing comfort. In addition, although the closed-cell structure of EPS material provides good cushioning performance, it also causes the problem of poor breathability, which is easy to produce a stuffy feeling when worn for a long time.

[0004] On the other hand, some manufacturers have tried to use expanded polypropylene (EPP) to replace EPS in an attempt to solve the problem of multiple impact protection. EPP does perform well in repeated impacts, but the use of EPP alone will result in insufficient protection of the helmet in high-intensity single impacts. In addition, pure EPP helmets are usually heavy and do not meet the requirements of lightweight.

[0005] In terms of production technology, most mountaineering helmets currently use a step-by-step molding and then assembly method. Although this method has a simple production process, it results in insufficient bonding between materials, affecting the overall performance and durability of the helmet. Some manufacturers try to use adhesives to enhance the bonding between different material layers, but this introduces new problems, such as increased production costs and possible environmental pollution.

[0006] In summary, existing technologies face multiple challenges in the design and manufacture of mountaineering helmets: how to provide continuous and effective impact protection while ensuring lightweight; how to balance safety performance and wearing comfort; and how to improve the overall durability and environmental adaptability of helmets. Solving these problems is crucial to improving the safety of mountaineering and the experience of participants. Summary of the invention

[0007] The present invention aims to solve the above technical problems and provide a simple mountaineering helmet production process that can simultaneously meet the requirements of high safety, light weight, comfort and durability. Through innovative material combination and preparation method, the present invention achieves complementary advantages and synergistic enhancement of the performance of EPP and EPS materials, overcoming the limitations of a single material structure. At the same time, the use of an integrated molding process not only simplifies the production process, but also significantly improves the overall performance of the product.

[0008] The present invention proposes a simple mountaineering helmet production process, comprising the following steps:

[0009] (1) First, prepare raw materials, which include:

[0010] Expanded polypropylene (EPP) 80-83 parts by weight;

[0011] Expanded polystyrene (EPS) 17-20 parts by weight;

[0012] Polycarbonate PC 1-5 parts by weight;

[0013] (2) Secondly, the EPP main body is formed, including:

[0014] a) injecting EPP particles and PC into the mold;

[0015] b) injecting steam to heat and pressurize the EPP particles to expand and fuse;

[0016] c) cooling to form;

[0017] d) Open the mold and take out the EPP body;

[0018] (3) Then, the EPS inner layer is formed and the PC outer layer is formed, including:

[0019] a) Place the molded EPP body and PC into the EPS molding mold;

[0020] b) injecting pre-foamed EPS particles into the inner cavity of the EPP body;

[0021] c) injecting steam to heat and pressurize the EPS particles to expand and combine with the EPP body and PC;

[0022] d) cooling to form;

[0023] e) Open the mold and take out the finished product.

[0024] Preferably, the process parameters for forming the EPP body include:

[0025] Steam delay 0.2-0.4 seconds;

[0026] Steam start direction is standard;

[0027] Punching time 4-6 seconds;

[0028] Filling and cutting steam MI time 23-27 seconds;

[0029] Fill and cut steam MII time 22-26 seconds;

[0030] Double-sided steam MI and MII time are 11-15 seconds each;

[0031] Total steam time 45-55 seconds;

[0032] Condensation time 1.5-2.5 seconds;

[0033] The cooling time for MI and MII is 130-150 seconds respectively.

[0034] Preferably, the pressure parameters for molding the EPP body include:

[0035] Heat MI and MII pressure 0-0.1 bar before filling;

[0036] Die-cutting steam MI pressure 0.7-0.8 bar;

[0037] Die-cutting steam MII pressure 0.75-0.85bar;

[0038] Double-sided steam MII pressure 0.75-0.85bar;

[0039] Packing pressure 0.4-0.6bar.

[0040] Preferably, the process parameters for forming the EPS inner layer include:

[0041] Rapid mold opening distance 110-130mm;

[0042] Rapid mold closing distance 380-420mm;

[0043] Total steaming time 40-50 seconds;

[0044] The cooling time for MI and MII is 130-150 seconds respectively.

[0045] Preferably, the pressure parameters for forming the EPS inner layer include:

[0046] Heat MI and MII pressure 0-0.1 bar before filling;

[0047] Die-cutting steam MI pressure 0.7-0.8 bar;

[0048] Die-cutting steam MII pressure 0.75-0.85bar;

[0049] Double-sided steam MII pressure 0.75-0.85bar;

[0050] Packing pressure 0.4-0.6bar.

[0051] Preferably, the following common parameters are also included:

[0052] Open the drain valve;

[0053] Blowback time 2.5-3.5 seconds;

[0054] Vacuum demoulding;

[0055] Open push rod 75-85mm;

[0056] Open the push rod to contain 45-55mm of gas;

[0057] Close the push rod 0-5mm;

[0058] Slow push 300-340mm;

[0059] Maximum stroke 960-980mm;

[0060] Synchronous pause 0.4-0.6 seconds.

[0061] Preferably, after the EPP main body is formed, the EPP main body and PC are directly placed in an EPS forming mold to form the EPS inner layer, thereby achieving integrated forming of EPP, EPS and PC.

[0062] Preferably, by controlling the weight ratio of EPP, EPS and PC, a gradient structure design is formed, wherein the PC outer layer provides multiple impact protection and the EPS and EPP inner layers provide lightweight and single high-intensity impact protection.

[0063] The beneficial effects of the present invention are mainly reflected in the following aspects:

[0064] First, the invention successfully achieves excellent multiple impact protection through precise proportioning and integrated molding of EPP and EPS. The PC outer layer has excellent protection against sharp punctures, the EPP layer provides excellent elastic recovery and energy absorption, and the EPS layer plays a key role in high-intensity single impacts. The synergistic effect of the three materials enables the helmet to continuously provide a high level of safety protection during long-term, complex mountaineering activities.

[0065] Secondly, the invention cleverly balances lightweight and protective performance. By optimizing the ratio of EPP and EPS and using precisely controlled molding parameters, the weight of the helmet is successfully reduced while maintaining a high level of impact absorption. This lightweight design significantly improves wearing comfort and is particularly suitable for long-term mountaineering activities.

[0066] Furthermore, the integrated molding process of the present invention not only improves production efficiency, but also significantly enhances the bonding strength between the EPP and EPS layers. This tightly combined composite structure greatly improves the overall strength and durability of the helmet and extends the service life of the product.

[0067] In addition, the innovative design of the present invention brings an unexpected temperature regulation effect. The open foam structure of the EPP layer and the unique interface formed by the EPS layer provide good thermal insulation performance and ensure excellent air permeability. This feature effectively solves the problem of traditional mountaineering helmets being easily stuffy and greatly improves the comfort of long-term wearing.

[0068] Finally, the production process of the present invention does not use additional adhesives or chemical additives, which not only simplifies the production process and reduces costs, but also makes the product more environmentally friendly and easy to recycle.

[0069] In general, the simple mountaineering helmet production process provided by the present invention has achieved significant breakthroughs in many aspects such as safety, comfort, lightness and durability, opening up a new direction for the development of mountaineering safety equipment, and is expected to provide mountaineering enthusiasts with safer, more comfortable and reliable head protection solutions. BRIEF DESCRIPTION OF THE DRAWINGS

[0070] Figure 1 It is a schematic structural diagram of the simple mountaineering helmet of the present invention.

[0071] Figure 2 It is a cross-sectional view of the simple mountaineering helmet of the present invention. DETAILED DESCRIPTION

[0072] In order to further explain the technical means and effects adopted by the present invention to achieve the predetermined invention purpose, the specific implementation methods, structures, features and effects thereof are described in detail below in conjunction with the accompanying drawings and preferred embodiments. In the following description, different "one embodiment" or "another embodiment" does not necessarily refer to the same embodiment. In addition, specific features, structures or characteristics in one or more embodiments may be combined in any suitable form.

[0073] Unless defined otherwise, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs.

[0074] Please refer to Figure 1-2 Example 1: A method for preparing a lightweight, high-performance, simple mountaineering helmet

[0075] This embodiment provides a method for preparing a lightweight, high-performance, simple mountaineering helmet, which uses an innovative combination of EPP and EPS and achieves excellent safety performance and comfort through a precisely controlled integrated molding process.

[0076] Specifically, the preparation method of this embodiment includes the following steps:

[0077] (1) First, prepare the raw materials, including:

[0078] 80 parts by weight of expanded polypropylene (EPP);

[0079] Expanded polystyrene (EPS) 20 parts by weight;

[0080] Polycarbonate PC 5 parts by weight;

[0081] (2) Secondly, the EPP main body is formed. The specific steps are as follows:

[0082] a) injecting EPP particles (particle size 0.5-2.0 mm) into the mold;

[0083] b) Inject steam to heat and pressurize the EPP particles to fuse. In this process, the steam delay is set to 0.2 seconds, the die time is 4 seconds, the filling and cutting steam MI time is 23 seconds, the filling and cutting steam MII time is 22 seconds, the double-sided steam MI and MII time are 11 seconds each, and the total steam time is 45 seconds;

[0084] c) cooling, the condensation time is 1.5 seconds, and the cooling times MI and MII are 130 seconds respectively;

[0085] d) Finally, open the mold and take out the EPP body.

[0086] During the EPP main body molding process, the pressure parameters were set as follows: heating MI and MII pressures before filling were 0 bar, die-cutting steam MI pressure was 0.7 bar, die-cutting steam MII pressure was 0.75 bar, double-sided steam MII pressure was 0.75 bar, and filling pressure was 0.4 bar.

[0087] (3) Then, the EPS inner layer is formed and the PC outer layer is formed. The specific steps are as follows:

[0088] a) Place the molded EPP body and PC into the EPS molding mold;

[0089] b) injecting pre-foamed EPS particles into the inner cavity of the EPP body;

[0090] c) Inject steam to heat and pressurize, so that the EPS particles expand and combine with the EPP body and PC. In this process, the quick mold opening distance is 110mm, the quick mold closing distance is 380mm, and the total steam time is 40 seconds;

[0091] d) cooling, the cooling time MI and MII are 130 seconds respectively;

[0092] e) Finally, open the mold and take out the finished product.

[0093] During the EPS inner layer molding process, the pressure parameters were set as follows: heating MI and MII pressures before filling were 0 bar, die-cutting steam MI pressure was 0.7 bar, die-cutting steam MII pressure was 0.75 bar, double-sided steam MII pressure was 0.75 bar, and filling pressure was 0.4 bar.

[0094] In addition, this embodiment also includes the following common parameters: open the drain valve, the back-blowing time is 2.5 seconds, vacuum demolding is adopted, the push rod is opened to 75mm, the push rod is opened to contain air to 45mm, the push rod is closed to 0mm, the slow push rod is pushed to 300mm, the maximum stroke is 960mm, and the synchronous pause is 0.4 seconds.

[0095] Preferably, in the embodiment of the present invention, the EPP outer layer provides excellent multiple impact protection, which is mainly due to the unique molecular structure and foam morphology of the EPP material. The molecular chain of EPP has good elasticity and resilience, can effectively absorb and disperse energy when impacted, and quickly return to its original state after the impact ends. This property enables the EPP outer layer to continue to play a protective role in multiple impacts, greatly improving the service life and safety performance of the mountaineering helmet.

[0096] At the same time, the EPS inner layer takes advantage of its lightweight and single high-intensity impact protection. The closed-cell foam structure of EPS gives it an extremely low density, significantly reducing the overall weight of the helmet and improving wearing comfort. When subjected to a high-intensity impact, the EPS inner layer can absorb a large amount of energy through the compression and rupture of the foam structure, effectively protecting the user's head from injury.

[0097] Through the ingenious combination of EPP and EPS, the mountaineering helmet prepared in this embodiment achieves a perfect balance between light weight and high performance, providing mountaineering enthusiasts with safer and more comfortable head protection equipment.

[0098] Example 2: A method for preparing a high-strength and durable simple mountaineering helmet

[0099] This embodiment provides a method for preparing a high-strength and durable simple mountaineering helmet. The method achieves higher strength and durability by adjusting the ratio of EPP and EPS and optimizing preparation parameters.

[0100] Specifically, the preparation method of this embodiment includes the following steps:

[0101] (1) First, prepare the raw materials, including:

[0102] Expanded polypropylene (EPP) 83 parts by weight;

[0103] Expanded polystyrene (EPS) 17 parts by weight;

[0104] Polycarbonate PC4 parts by weight;

[0105] (2) Secondly, the EPP main body is formed. The specific steps are as follows:

[0106] a) injecting EPP particles (particle size 0.5-2.0 mm) into the mold;

[0107] b) Inject steam to heat and pressurize to expand and fuse the EPP particles and PC. In this process, the steam delay is set to 0.4 seconds, the die time is 6 seconds, the filling and cutting steam MI time is 27 seconds, the filling and cutting steam MII time is 26 seconds, the double-sided steam MI and MII time are 15 seconds each, and the total steam time is 55 seconds;

[0108] c) cooling, the condensation time is 2.5 seconds, and the cooling times MI and MII are 150 seconds respectively;

[0109] d) Finally, open the mold and take out the EPP body.

[0110] During the EPP main body molding process, the pressure parameters were set as follows: heating MI and MII pressures before filling were 0.1 bar, die-cutting steam MI pressure was 0.8 bar, die-cutting steam MII pressure was 0.85 bar, double-sided steam MII pressure was 0.85 bar, and filling pressure was 0.6 bar.

[0111] (3) Then, the EPS inner layer is formed and the PC outer layer is formed. The specific steps are as follows:

[0112] a) Place the molded EPP body and PC into the EPS molding mold;

[0113] b) injecting pre-foamed EPS particles into the inner cavity of the EPP body;

[0114] c) Inject steam, heat and pressurize to expand the EPS particles and combine with the EPP body and PC. In this process, the quick mold opening distance is 130mm, the quick mold closing distance is 420mm, and the total steam time is 50 seconds;

[0115] d) cooling, the cooling time MI and MII are 150 seconds respectively;

[0116] e) Finally, open the mold and take out the finished product.

[0117] During the EPS inner layer molding process, the pressure parameters were set as follows: heating MI and MII pressures before filling were 0.1 bar, die-cutting steam MI pressure was 0.8 bar, die-cutting steam MII pressure was 0.85 bar, double-sided steam MII pressure was 0.85 bar, and filling pressure was 0.6 bar.

[0118] In addition, this embodiment also includes the following common parameters: open the drain valve, the back-blowing time is 3.5 seconds, vacuum demolding is adopted, the push rod is opened to 85mm, the push rod is opened to contain air to 55mm, the push rod is closed to 5mm, the slow push rod is pushed to 340mm, the maximum stroke is 980mm, and the synchronous pause is 0.6 seconds.

[0119] Preferably, in the embodiment of the present invention, by increasing the proportion of EPP and optimizing the preparation parameters, the strength and durability of the mountaineering helmet are significantly improved. The higher EPP content (83 parts by weight) makes the outer layer of the helmet have better impact resistance and shape memory. This is mainly because the degree of cross-linking between the EPP molecular chains is higher, which can more effectively disperse the stress when subjected to external force, and quickly return to its original state after the external force disappears.

[0120] At the same time, by extending the steam treatment time and increasing the pressure, better fusion between EPP particles is promoted, forming a more dense and uniform foam structure. This optimized structure not only improves the overall strength of the helmet, but also enhances its puncture resistance and fatigue resistance.

[0121] Although the proportion of the EPS inner layer is slightly reduced (17 parts by weight), the EPS foam structure is made more uniform and stable by optimizing the preparation parameters, such as increasing the total steam time and cooling time. This structural optimization not only maintains the excellent energy absorption characteristics of EPS, but also improves its bonding strength with the EPP layer, further enhancing the overall performance of the helmet.

[0122] Through this innovative formula and process optimization, the mountaineering helmet prepared in this embodiment not only has excellent protective performance, but also has a longer service life, and can provide long-lasting and reliable head protection in harsh mountaineering environments.

[0123] Example 3: A method for preparing a lightweight, comfortable and simple mountaineering helmet

[0124] This embodiment provides a method for preparing a lightweight, comfortable and simple mountaineering helmet. The method achieves lighter weight and higher comfort by adjusting the ratio of EPP and EPS and optimizing preparation parameters.

[0125] Specifically, the preparation method of this embodiment includes the following steps:

[0126] (1) First, prepare the raw materials, including:

[0127] Expanded polypropylene (EPP) 81 parts by weight;

[0128] Expanded polystyrene (EPS) 19 parts by weight;

[0129] Polycarbonate PC 1 part by weight;

[0130] (2) Secondly, the EPP main body is formed. The specific steps are as follows:

[0131] a) injecting EPP particles (particle size 0.5-2.0 mm) into the mold;

[0132] b) Inject steam to heat and pressurize to expand and fuse the EPP particles and PC. In this process, the steam delay is set to 0.3 seconds, the die time is 5 seconds, the filling and cutting steam MI time is 25 seconds, the filling and cutting steam MII time is 24 seconds, the double-sided steam MI and MII time are 13 seconds each, and the total steam time is 50 seconds;

[0133] c) cooling, the condensation time is 2 seconds, and the cooling times MI and MII are 140 seconds respectively;

[0134] d) Finally, open the mold and take out the EPP body.

[0135] During the EPP main body molding process, the pressure parameters are set as follows: the heating MI and MII pressures before filling are 0.05 bar, the die-cutting steam MI pressure is 0.75 bar, the die-cutting steam MII pressure is 0.8 bar, the double-sided steam MII pressure is 0.8 bar, and the filling pressure is 0.5 bar.

[0136] (3) Then, the EPS inner layer is formed and the PC outer layer is formed. The specific steps are as follows:

[0137] a) Place the molded EPP body and PC into the EPS molding mold;

[0138] b) injecting pre-foamed EPS particles into the inner cavity of the EPP body;

[0139] c) Inject steam, heat and pressurize to expand the EPS particles and combine with the EPP body and PC. In this process, the quick mold opening distance is 120mm, the quick mold closing distance is 400mm, and the total steam time is 45 seconds;

[0140] d) cooling, the cooling time MI and MII are 140 seconds respectively;

[0141] e) Finally, open the mold and take out the finished product.

[0142] During the EPS inner layer molding process, the pressure parameters were set as follows: heating MI and MII pressures before filling were 0.05 bar, die-cutting steam MI pressure was 0.75 bar, die-cutting steam MII pressure was 0.8 bar, double-sided steam MII pressure was 0.8 bar, and filling pressure was 0.5 bar.

[0143] In addition, this embodiment also includes the following common parameters: open the drain valve, the back-blowing time is 3 seconds, vacuum demolding is adopted, the push rod is opened to 80mm, the push rod is opened to contain air to 50mm, the push rod is closed to 2.5mm, the slow push rod is pushed to 320mm, the maximum stroke is 970mm, and the synchronous pause is 0.5 seconds.

[0144] Preferably, in the embodiment of the present invention, by fine-tuning the ratio of EPP and EPS and optimizing the preparation parameters, the lightweight and comfort improvement of the mountaineering helmet is successfully achieved. The EPP content is kept at a high level (81 parts by weight) to ensure that the helmet has sufficient impact resistance, while the slightly increased EPS ratio (19 parts by weight) further reduces the overall weight of the helmet.

[0145] During the preparation process, we successfully controlled the foam structure of EPP and EPS by adjusting the steam treatment time and pressure parameters. For the EPP layer, medium-intensity steam treatment and pressure were used, so that the EPP particles could fully expand but still maintain a certain gap, forming a lighter and more elastic foam structure. This structure not only reduces the weight of the helmet, but also improves its breathability and comfort.

[0146] For the EPS inner layer, by precisely controlling the steam time and cooling parameters, we obtained a low-density but uniform and stable EPS foam structure. This structure further reduces the weight of the helmet while maintaining good energy absorption characteristics. In addition, the optimized EPS inner layer forms a more coordinated transition with the EPP outer layer, improving the overall comfort of the helmet.

[0147] Through this innovative formula adjustment and process optimization, the mountaineering helmet prepared in this embodiment not only maintains excellent protective performance, but also achieves lighter weight and higher comfort. This lightweight design significantly reduces the fatigue of the user during long-term wearing, and is particularly suitable for mountaineering activities that require wearing a helmet for a long time. At the same time, the optimized foam structure improves the breathability of the helmet, effectively improves the problem of stuffiness during long-term wear, and provides users with a more comfortable use experience.

[0148] Example 4: A method for preparing a simple mountaineering helmet with balanced performance

[0149] This embodiment provides a method for preparing a simple mountaineering helmet with balanced performance. The method achieves an optimal balance of safety, comfort and durability by precisely adjusting the ratio of EPP and EPS and preparation parameters.

[0150] Specifically, the preparation method of this embodiment includes the following steps:

[0151] (1) First, prepare the raw materials, including:

[0152] Expanded polypropylene (EPP) 82 parts by weight;

[0153] Expanded polystyrene (EPS) 18 parts by weight;

[0154] Polycarbonate PC 3 parts by weight;

[0155] (2) Secondly, the EPP main body is formed. The specific steps are as follows:

[0156] a) injecting EPP particles (particle size 0.5-2.0 mm) into the mold;

[0157] b) Inject steam to heat and pressurize to expand and fuse the EPP particles and PC. In this process, the steam delay is set to 0.3 seconds, the die time is 5 seconds, the filling and cutting steam MI time is 25 seconds, the filling and cutting steam MII time is 24 seconds, the double-sided steam MI and MII time are 13 seconds each, and the total steam time is 50 seconds;

[0158] c) cooling, the condensation time is 2 seconds, and the cooling times MI and MII are 140 seconds respectively;

[0159] d) Finally, open the mold and take out the EPP body.

[0160] During the EPP main body molding process, the pressure parameters were set as follows: heating MI and MII pressures before filling were 0.05 bar, die-cutting steam MI pressure was 0.75 bar, die-cutting steam MII pressure was 0.8 bar, double-sided steam MII pressure was 0.8 bar, and filling pressure was 0.5 bar.

[0161] (3) Then, the EPS inner layer is formed and the PC outer layer is formed. The specific steps are as follows:

[0162] a) Place the molded EPP body and PC into the EPS molding mold;

[0163] b) injecting pre-foamed EPS particles into the inner cavity of the EPP body;

[0164] c) Inject steam to heat and pressurize, so that the EPS particles expand and combine with the EPP body and PC. In this process, the quick mold opening distance is 120mm, the quick mold closing distance is 400mm, and the total steam time is 45 seconds;

[0165] d) cooling, the cooling time MI and MII are 140 seconds respectively;

[0166] e) Finally, open the mold and take out the finished product.

[0167] During the EPS inner layer molding process, the pressure parameters were set as follows: heating MI and MII pressures before filling were 0.05 bar, die-cutting steam MI pressure was 0.75 bar, die-cutting steam MII pressure was 0.8 bar, double-sided steam MII pressure was 0.8 bar, and filling pressure was 0.5 bar.

[0168] In addition, this embodiment also includes the following common parameters: open the drain valve, the back-blowing time is 3 seconds, vacuum demolding is adopted, the push rod is opened to 80mm, the push rod is opened to contain air to 50mm, the push rod is closed to 2.5mm, the slow push rod is pushed to 320mm, the maximum stroke is 970mm, and the synchronous pause is 0.5 seconds.

[0169] Preferably, in the embodiment of the present invention, the optimal balance of the performance of the mountaineering helmet is successfully achieved by precisely controlling the ratio of EPP to EPS (82:18) and optimizing the preparation parameters. This ratio makes full use of the excellent impact resistance of EPP and the lightweight characteristics of EPS, and at the same time achieves the best synergy of the performance of the three materials through the fine control of the process parameters.

[0170] During the EPP body molding process, medium-intensity steam treatment and pressure parameters are used, which allows the EPP particles to fully expand and form a stable network structure while retaining appropriate elasticity. This structure can provide excellent multiple impact protection while maintaining good comfort. In particular, by controlling the time of filling and cutting steam and double-sided steam, we have successfully created a subtle density gradient in the EPP layer. This gradient structure can more effectively absorb and disperse impact energy.

[0171] For the EPS inner layer, by precisely controlling the steam time and pressure parameters, we obtained EPS foam with moderate density and uniform structure. This structure ensures the lightweight of the helmet while maintaining excellent energy absorption characteristics. It is particularly worth mentioning that by optimizing the rapid opening and closing mold parameters during the EPS molding process, we significantly improved the bonding strength between the EPS layer and the EPP layer, which not only improves the overall strength of the helmet, but also enhances its anti-peeling performance.

[0172] In addition, the balanced preparation parameters used in this embodiment, such as moderate back blowing time and ejection distance, ensure the consistency and stability of the finished product. This process not only improves product quality, but also enhances the controllability and efficiency of the production process.

[0173] Through this innovative formula design and process optimization, the mountaineering helmet prepared in this embodiment achieves a perfect balance of safety, comfort and durability. It can not only provide users with reliable head protection, but also has excellent comfort and a long service life. This balanced performance design enables the helmet to adapt to various mountaineering environments and usage requirements, providing a comprehensive and reliable head protection solution for mountaineering enthusiasts.

[0174] Through the above four embodiments, the present invention fully demonstrates the flexibility and advantages of the simple mountaineering helmet production process of the present invention. From high-strength and durable type (Example 2) to lightweight and comfortable type (Example 3), and then to balanced performance type (Example 4), each embodiment is optimized for specific performance requirements. This flexible process not only meets the needs of different users, but also lays the foundation for further optimization and customized production of future products. By precisely controlling the ratio of EPP and EPS and the preparation parameters, we have successfully achieved a comprehensive improvement in the safety, comfort and durability of mountaineering helmets, providing mountaineering enthusiasts with safer, more comfortable and reliable head protection equipment.

[0175] Comparative Example 1: Preparation method of traditional EPS single-layer mountaineering helmet

[0176] This comparative example is intended to demonstrate the performance difference between a traditional single-layer EPS mountaineering helmet and the EPP-EPS composite structure of the present invention, corresponding to Example 1.

[0177] The method comprises the following steps:

[0178] (1) First, raw materials were prepared, including only 100 parts by weight of expanded polystyrene (EPS).

[0179] (2) Secondly, EPS helmet molding is carried out. The specific steps are as follows:

[0180] a) injecting EPS particles into a mold;

[0181] b) injecting steam to heat and pressurize the EPS particles to expand and fuse. In this process, the same steam parameters as in Example 1 are used;

[0182] c) cooling, using the same cooling parameters as in Example 1;

[0183] d) Finally, open the mold and take out the finished product.

[0184] Preferably, in this comparative example, although the single-layer EPS structure can provide good single impact protection and lightweight properties, it lacks the multiple impact protection capability brought by the EPP layer. By comparison with Example 1, it can be clearly seen that the EPP-EPS composite structure of the present invention has advantages in multiple impact protection and overall performance balance.

[0185] Comparative Example 2: Preparation method of high EPP ratio mountaineering helmet

[0186] This comparative example is intended to verify the effect of excessively high EPP ratio on the performance of mountaineering helmets, corresponding to Example 2.

[0187] The method comprises the following steps:

[0188] (1) First, prepare the raw materials, including:

[0189] 90 parts by weight of expanded polypropylene (EPP);

[0190] 10 parts by weight of expanded polystyrene (EPS);

[0191] Polycarbonate PC 4 parts by weight;

[0192] (2) Subsequently, the EPP main body and the EPS inner layer were formed according to the method of Example 2.

[0193] Preferably, in this comparative example, although the excessively high EPP ratio provides excellent multiple impact protection, it also increases the overall weight of the helmet and reduces comfort. By comparison with Example 2, it can be proved that the EPP-EPS ratio (83:17) selected by the present invention achieves the best balance between strength, durability and comfort.

[0194] Comparative Example 3: Preparation method of low pressure parameter mountaineering helmet

[0195] This comparative example is intended to verify the influence of pressure parameters on the performance of mountaineering helmets, corresponding to Example 3.

[0196] The method comprises the following steps:

[0197] (1) First, prepare the raw materials using the same proportions as in Example 3.

[0198] (2) Secondly, the EPP main body and EPS inner layer molding are performed, but all pressure parameters are reduced by 50%.

[0199] Preferably, in this comparative example, the lower pressure parameter leads to insufficient fusion of EPP and EPS particles, and the formed foam structure is loose and uneven. By comparison with Example 3, it can be proved that the pressure parameter used in the present invention is crucial to obtain an ideal foam structure and material properties.

[0200] Comparative Example 4: Preparation method of non-gradient structure mountaineering helmet

[0201] This comparative example is intended to verify the effect of gradient structure design on the performance of mountaineering helmets, corresponding to Example 4.

[0202] The method comprises the following steps:

[0203] (1) First, prepare the raw materials using the same proportions as in Example 4.

[0204] (2) Secondly, the EPP main body and the EPS inner layer are formed, but in the preparation process, the time difference between the filling and cutting steam and the double-sided steam is not used, but a uniform steam time is used.

[0205] Preferably, in this comparative example, due to the lack of a gradient structure, the helmet does not perform as well in terms of impact absorption and energy dispersion as Example 4. This highlights the importance of the present invention in creating a subtle density gradient by precisely controlling steam parameters, demonstrating the key role of the gradient structure in improving the overall performance of the helmet.

[0206] Comparative Example 5: Preparation method of mountaineering helmet with too short cooling time

[0207] This comparative example is intended to verify the effect of cooling time on the performance of mountaineering helmets, corresponding to Example 1.

[0208] The method comprises the following steps:

[0209] (1) First, prepare the raw materials using the same proportions as in Example 1.

[0210] (2) Secondly, the EPP main body and EPS inner layer are molded, but the cooling time is shortened to 50% of the original.

[0211] Preferably, in this comparative example, too short a cooling time leads to an unstable foam structure and residual internal stress, which affects the dimensional stability and long-term performance of the helmet. By comparison with Example 1, it can be proved that the sufficient cooling time adopted in the present invention is crucial to obtain a high-quality, high-performance mountaineering helmet.

[0212] Comparative Example 6: Preparation method of non-integrated molded mountaineering helmet

[0213] This comparative example is intended to verify the effect of the integrated molding process on the performance of mountaineering helmets, corresponding to Example 4.

[0214] The method comprises the following steps:

[0215] (1) First, prepare the raw materials using the same proportions as in Example 4.

[0216] (2) Secondly, the EPP outer layer and the EPS inner layer are independently molded.

[0217] (3) Finally, the molded EPP outer layer and EPS inner layer are assembled together using an adhesive.

[0218] Preferably, in this comparative example, although the non-integrated molding method uses the same material ratio, the lack of direct interface bonding leads to low interlayer bonding strength, which affects the overall performance and durability of the helmet. By comparing with Example 4, it can be clearly seen that the integrated molding process of the present invention has significant advantages in improving material interface bonding strength and overall performance.

[0219] In order to comprehensively evaluate the performance of the simple mountaineering helmet of the present invention, we designed the following test experiments:

[0220] 1. Impact resistance test

[0221] First, we use the impact absorption test method in the EN1078 standard. The helmet is fixed on the head shape, and then it falls freely from a height of 2 meters. The maximum acceleration of the head shape is measured using an accelerometer. Secondly, we conduct multiple impact tests, with 5 consecutive impacts, to evaluate the continuous protection ability of the helmet.

[0222] 2. Weight and comfort assessment

[0223] We used a precision electronic scale to measure the weight of the helmet. In addition, we invited 20 volunteers to wear the helmet for 2 hours and subjectively rate the comfort using a 1-10 scale.

[0224] 3. Thermal performance and air permeability test

[0225] A thermal imaging camera was used to observe the heat distribution of the helmet under simulated use conditions. At the same time, a gas permeability tester was used to measure the breathability of the helmet.

[0226] 4. Durability test

[0227] After 50 impacts, the helmets were evaluated for appearance changes and performance degradation. Scanning electron microscopy (SEM) was used to observe changes in the material's microstructure.

[0228] 5. Interface bonding strength test

[0229] The peel test method was used to evaluate the bonding strength between the EPP outer layer and the EPS inner layer.

[0230] The test results are shown in Table 1-3

[0231] Table 1: Impact resistance and multiple impact protection

[0232]

[0233]

[0234] Table 2: Weight, comfort and thermal performance

[0235]

[0236] Table 3: Durability and interface bonding strength

[0237]

[0238]

[0239] Based on the above test results, we can deeply analyze the superiority and unexpected technical effects of the present invention:

[0240] 1.Excellent multiple impact protection

[0241] As can be seen from Table 1, the embodiments of the present invention performed well in the multiple impact tests, especially Embodiment 2 and Embodiment 4, whose acceleration increases after the fifth impact were only 6.1% and 5.7%. This is much better than the 29.7% increase of Comparative Example 1 (traditional EPS single-layer structure). This result fully demonstrates the superiority of the EPP-EPS composite structure in providing continuous protection.

[0242] It is worth noting that Example 4 exhibits the best multiple impact protection performance, thanks to its optimized EPP-EPS ratio (82:18) and carefully designed gradient structure. The elastic deformation ability of the EPP layer and the energy absorption characteristics of the EPS layer form a perfect synergistic effect, which can not only effectively absorb a single strong impact, but also maintain stable protection performance in multiple impacts.

[0243] 2. A clever balance between lightness and comfort

[0244] The data in Table 2 show that the present invention successfully achieves a balance between lightness and comfort. While maintaining excellent protection performance, Example 3 weighs only 305g and has a comfort rating of 8.7 points. This result surpasses the traditional single-layer EPS helmet (Comparative Example 1) and the high EPP ratio helmet (Comparative Example 2).

[0245] It is worth mentioning that although the weight of Example 4 is slightly higher (315 g), it still obtains a high comfort score of 8.5 points. This shows that the present invention successfully finds the best balance between weight and comfort by precisely controlling the ratio of EPP and EPS and the molding process.

[0246] 3.Excellent thermal performance and breathability

[0247] The thermal performance test results show that all the embodiments of the present invention exhibit lower maximum surface temperature and higher gas permeability. In particular, the maximum surface temperatures of Embodiments 3 and 4 are 33.8°C and 34.0°C respectively, while maintaining a higher gas permeability (50cm 3 / s and 48cm 3 / s). This performance is significantly better than that of the traditional single-layer EPS helmet (Comparative Example 1) and the non-integrated molded helmet (Comparative Example 6).

[0248] This excellent thermal performance and breathability is due to the unique EPP-EPS composite structure and integrated molding process of the present invention. The open foam structure of the EPP layer provides an ideal channel for heat dissipation and air circulation, while the EPS layer provides additional thermal insulation while maintaining lightweight.

[0249] 4.Excellent durability and interface bonding strength

[0250] The data in Table 3 highlight the outstanding performance of the present invention in terms of durability and material interface bonding. Example 2 only shows 5.2% performance degradation after 50 impacts, and the EPP-EPS interface bonding strength is as high as 14.2 N / cm. This is far superior to the non-integrated comparative example 6 (11.2% degradation, 7.2 N / cm bonding strength).

[0251] This result demonstrates the key role of the integrated molding process of the present invention. By molding the EPS inner layer directly within the EPP body, we achieved a close combination of the three materials to form an integrated composite structure. This structure not only improves the overall strength of the helmet, but also significantly improves its long-term performance.

[0252] 5. Unexpected synergies

[0253] Through in-depth analysis of test data, we found that the present invention also brings some unexpected technical effects:

[0254] First, the EPP-EPS composite structure exhibited an unexpected temperature regulation capability. While maintaining excellent thermal insulation, Example 4 also exhibited excellent air permeability. This property may be due to the unique interface structure formed by EPP and EPS at the microscale, which not only blocks heat conduction but also creates an ideal channel for air circulation.

[0255] Secondly, we observed that after multiple impacts, the performance degradation of Examples 2 and 4 was much lower than expected. This shows that the EPP-EPS composite structure not only provides immediate impact protection, but also has the property of "self-healing". We speculate that this may be due to the fact that the EPP layer can quickly recover to its original shape after being impacted, and the deformation of the EPS layer can be compensated to a certain extent by the elastic deformation of the EPP layer.

[0256] Finally, the interface bonding strength test revealed an interesting phenomenon: the EPP-EPS interface bonding strength of Example 2 and Example 4 was not only higher than that of other samples, but also slightly increased after multiple impacts. This may be because during the impact process, the microstructure of the three materials was reorganized at the interface, further enhancing the interface bonding.

[0257] Through a series of comprehensive tests and in-depth analysis, we have confirmed the excellent performance and innovative value of the simple mountaineering helmet production process of the present invention. The EPP-EPS composite structure, integrated molding process and precisely controlled preparation parameters have jointly created a new mountaineering helmet that excels in safety, comfort and durability. In particular, Example 4 shows the best comprehensive performance and can be regarded as the best embodiment of the present invention.

[0258] This invention not only solves the problems of traditional mountaineering helmets in multiple impact protection, weight and comfort balance, but also brings a series of unexpected technical effects. These innovations and superior performance have opened up a new direction for the development of mountaineering safety equipment, and are expected to provide mountaineering enthusiasts with safer and more comfortable head protection solutions.

[0259] It should be noted that the above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the principles of the present invention should be included in the protection scope of the present invention.

Claims

1. A simple mountaineering helmet production process, characterized in that: The following steps are involved: (1) First, prepare raw materials, which include: 80-83 parts by weight of expanded polypropylene EPP; Expanded polystyrene EPS 17-20 parts by weight; Polycarbonate PC 1-5 parts by weight; (2) Secondly, the EPP main body is formed, including: a) injecting EPP particles and PC into the mold; b) injecting steam to heat and pressurize the EPP particles to expand and fuse; c) cooling to form; d) Open the mold and take out the EPP body; (3) Then, the EPS inner layer is formed and the PC outer layer is formed, including: a) Place the molded EPP body and PC into the EPS molding mold; b) injecting pre-foamed EPS particles into the inner cavity of the EPP body; c) injecting steam to heat and pressurize the EPS particles to expand and combine with the EPP body and PC; d) cooling to form; e) Open the mold and take out the finished product.

2. The simple mountaineering helmet production process according to claim 1, characterized in that: The process parameters of the EPP body molding include: Steam delay 0.2-0.4 seconds; Steam start direction is standard; Punching time 4-6 seconds; Filling and cutting steam MI time 23-27 seconds; Fill and cut steam MII time 22-26 seconds; Double-sided steam MI and MII time are 11-15 seconds each; Total steam time 45-55 seconds; Condensation time 1.5-2.5 seconds; The cooling time for MI and MII is 130-150 seconds respectively.

3. The simple mountaineering helmet production process according to claim 1, characterized in that: The pressure parameters for the EPP body molding include: Heat MI and MII pressure 0-0.1 bar before filling; Die-cutting steam MI pressure 0.7-0.8 bar; Die-cutting steam MII pressure 0.75-0.85bar; Double-sided steam MII pressure 0.75-0.85bar; Packing pressure 0.4-0.6bar.

4. The simple mountaineering helmet production process according to claim 1, characterized in that: The process parameters for forming the EPS inner layer include: Rapid mold opening distance 110-130mm; Rapid mold closing distance 380-420mm; Total steaming time 40-50 seconds; The cooling time for MI and MII is 130-150 seconds respectively.

5. The simple mountaineering helmet production process according to claim 1, characterized in that: The pressure parameters for the EPS inner layer molding include: Heat MI and MII pressure 0-0.1 bar before filling; Die-cutting steam MI pressure 0.7-0.8 bar; Die-cutting steam MII pressure 0.75-0.85bar; Double-sided steam MII pressure 0.75-0.85bar; Packing pressure 0.4-0.6bar.

6. The process for producing a simple mountaineering helmet according to any one of claims 1 to 5, characterized in that: The following common parameters are also included: Open the drain valve; Blowback time 2.5-3.5 seconds; Vacuum demoulding; Open push rod 75-85mm; Open the push rod to contain 45-55mm of gas; Close the push rod 0-5mm; Slow push 300-340mm; Maximum stroke 960-980mm; Synchronous pause 0.4-0.6 seconds.

7. The simple mountaineering helmet production process according to claim 1, characterized in that: After the EPP main body is formed, the EPP main body and PC are directly placed into an EPS forming mold to form the EPS inner layer, thereby achieving integrated forming of the EPP, EPS and PC.

8. The simple mountaineering helmet production process according to claim 1, characterized in that: By controlling the weight ratio of EPP, EPS and PC, a gradient structure design is formed, in which the PC outer layer provides multiple impact protection, and the EPS and EPP inner layers provide lightweight and single high-intensity impact protection.

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