WO2020000980A1

WO2020000980A1 - One-step forming process of ankle-foot orthosis and ankle-foot orthosis

Info

Publication number: WO2020000980A1
Application number: PCT/CN2018/125130
Authority: WO
Inventors: 刘若鹏; 赵治亚; 王唯贻
Original assignee: 深圳光启尖端技术有限责任公司
Priority date: 2018-06-26
Filing date: 2018-12-29
Publication date: 2020-01-02
Also published as: CN110641041A

Abstract

Disclosed are a one-step forming process of an ankle-foot orthosis and an ankle-foot orthosis. The one-step forming process of the ankle-foot orthosis comprises: step S1, manufacturing a mold and a pressure equalizing plate (2); step S2, paving a composite prepreg on the mold, and assembling the mold paved with the composite prepreg and the pressure equalizing plate (2) together to obtain an assembly; step S3, performing a vacuuming process and a curing process on the assembly sequentially, wherein the curing process includes: placing the assembly into a pressurized tank and pressurizing to a first preset pressure; and heating, according to a preset first temperature gradient, the assembly to a first preset temperature, and maintaining the temperature within a first time period; and step S4, performing a demolding process on the assembly to obtain an ankle-foot orthosis. The implementation of the described technical solution can save costs and increase production value.

Description

One-step forming process of ankle and foot orthosis and ankle and foot orthosis

Technical field

The invention relates to the field of manufacturing ankle and foot orthosis, in particular to a one-step forming process of an ankle and foot orthosis and an ankle and foot orthosis.

Background technique

Carbon fiber composite prosthetics and orthotics are new applications in the field of composite materials. Carbon fiber composite materials are ideal materials for the manufacture of prostheses and orthotics. The products meet the relevant management requirements of the medical and bioengineering industries. At present, the annual global demand for carbon fiber composite prostheses and orthotics is 800,000-1.2 million sets, and the sales are US $ 1-150 million. Ankle and foot orthosis is a typical orthosis product in the above field. Although the carbon fiber composite prosthetic foot and orthosis products have been greatly developed since the advent of the product, there are still some technical problems in the production and preparation of the product, the most significant of which is also a common problem with carbon fiber composite products is that the product is prone to delamination. And pores, the formation of the defect is mainly because the air enclosed in the product is not effectively exhausted by means of pressure or vacuum during the preparation process. After the defect is formed, the product strength and fatigue resistance will be reduced, which will affect its service life. .

In order to solve this problem, people have proposed different solutions, such as replacing composite materials with resin systems, evacuating the blanks in a vacuum box, and reducing the ambient temperature of the blanks. These methods either start with raw materials or from equipment Starting with it, the proportion of product defects is reduced to a certain extent.

However, for the manufacturing process of orthotics, it is the primary task to improve the primary qualification rate of the product through process improvement and improve the operating environment of the operator. For example, the prior art uses soft compression, that is, vulcanization, which has a certain hardness and toughness. Silicone rubber is pressurized, but most of them are silicone rubber flat plates (2D). Because the ankle and foot orthosis presents a tapered gradient from the position of the leg to the ankle, that is, the width is wide and the width is narrow, then a soft plate The pressure applied on the cover will inevitably cause the ankle to be under-pressurized. In some cases, wrinkles will appear, and serious resin accumulation will occur, which will affect the appearance of the product. Faced with the above situation, the existing method is to use two-step molding, that is, firstly lay up most of the prepreg for curing and then sanding, and finally lay the last two or two layers of prepreg for secondary curing. However, this This method does not completely eliminate the occurrence of defects, and at the same time increases the impact of fiber breaks on the performance of the part and related costs such as manpower and material resources.

Aiming at the problems in related technologies, no effective solution has been proposed at present.

Summary of the invention

Aiming at the problems in the related art, the present invention proposes a one-step molding process for ankle and foot orthosis and ankle and foot orthosis. It eliminates the pressure of the original silicone plate, and is made by selecting an expandable unvulcanized silicone rubber. A pressure equalizing plate (3D) that is more closely fitted to the molding mold to achieve the effect of one-step molding, thereby improving the first pass rate of the product through process improvement, and thereby improving the operating environment of the operator.

The technical solution of the present invention is implemented as follows:

According to one aspect of the present invention, a one-step forming process for an ankle and foot orthosis is provided.

The one-step forming process of the ankle and foot orthosis includes:

Step S1, manufacturing a mold and a pressure equalizing plate;

Step S2: lay the composite prepreg on the mold, and assemble the mold and the pressure equalizing plate after the composite prepreg is applied to obtain the assembly;

In step S3, the assembly is sequentially subjected to a vacuum treatment and a curing process, wherein the curing process includes: placing the assembly in a pressure tank and pressurizing it to a first preset pressure; according to a preset first temperature gradient, Heating the assembly to a first preset temperature and keeping it warm for a first period of time;

In step S4, the assembly is demoulded to obtain an ankle and foot orthosis.

According to an embodiment of the present invention, in step S2, the composite prepreg is laid on a transition area of the mold by means of a gradual lamination.

According to an embodiment of the present invention, the curing process further includes: heating the assembly to a second preset temperature according to a preset second temperature gradient, and maintaining heat and pressure for a second period of time.

According to an embodiment of the present invention, the curing process further includes:

Repeat the following steps: the pressure in the pressurized tank will be zero, and the vacuum tank will be evacuated in the third time period, and air will be introduced into the pressurized tank in the fourth time period;

Until the execution times are the same as the preset times, the loop is stopped;

Pressurize to a second preset pressure, and heat the assembly to a third preset temperature according to a preset third temperature gradient, and maintain heat and pressure for a third period of time.

According to an embodiment of the present invention, the vacuuming treatment includes: placing the assembly into a vacuum bag, and connecting the vacuum bag and a vacuum pump to perform the vacuuming treatment by the vacuum pump.

According to an embodiment of the present invention, performing demolding treatment on the assembly to obtain an ankle and foot orthosis includes: demolding the assembly to obtain a tibial portion, and the inner surface of the tibial portion is used for contacting the tibia of the human body. Fit; combine the tibia and the foot to receive the foot to get an ankle and foot orthosis.

According to an embodiment of the present invention, the one-step molding process further includes: Step S5, detecting the ankle and foot orthosis by using a pressure detection device.

According to an embodiment of the present invention, step S2 further includes: laying a breathable felt on the surface of the pressure equalizing plate in the assembly.

According to an embodiment of the present invention, in the process of manufacturing the pressure equalizing plate in step S1, a breathable felt is applied to the surface of the pressure equalizing plate, so as to obtain a pressure equalizing plate having a breathable felt.

According to an embodiment of the present invention, in step S2: the release agent and the composite prepreg are sequentially laid on the mold.

According to another aspect of the invention, an ankle and foot orthosis is provided.

The ankle-foot orthosis includes: the ankle-foot orthosis is made by a one-step forming process of any of the above-mentioned ankle-foot orthosis.

The beneficial technical effects of the present invention are:

In the present invention, a mold and a pressure equalizing plate are manufactured, and then the composite material prepreg is laid on the mold, and the mold and the pressure equalizing plate after the composite material prepreg is applied are assembled to obtain an assembly, and then the assembly is sequentially Vacuuming and curing, wherein the curing includes: putting the assembly into a pressure tank, pressurizing to a first preset pressure; and heating the assembly to the first according to a preset first temperature gradient Pre-set temperature and heat preservation for the first time period, and finally demoulding the assembly to obtain an ankle and foot orthosis, which can save costs and increase production value. Compared with the existing two-step curing molding, The improved one-step molding process saves half the amount of cans used in the autoclave, and in terms of materials, it saves the auxiliary materials such as breathable felt, insulation film, PE film and vacuum bag used in the original first curing. At the same time, in terms of personnel, it also reduced the one-time grinding process, saving labor costs. In addition, it also saved the bagging and demoulding work of the paving staff, saving time and improving For efficiency.

BRIEF DESCRIPTION OF THE DRAWINGS

In order to more clearly explain the embodiments of the present invention or the technical solutions in the prior art, the drawings used in the embodiments will be briefly introduced below. Obviously, the drawings in the following description are only some of the present invention. For those of ordinary skill in the art, other embodiments may be obtained based on these drawings without paying creative effort.

1 is a flowchart of a one-step molding process of an ankle and foot orthosis according to an embodiment of the present invention;

2 is a schematic diagram of each step of a one-step molding process of an ankle and foot orthosis according to a specific embodiment of the present invention;

FIG. 3 is a schematic diagram of the assembly according to an embodiment of the present invention;

4 is a flowchart of a one-step molding process of an ankle and foot orthosis according to a specific embodiment of the present invention.

detailed description

In the following, the technical solutions in the embodiments of the present invention will be clearly and completely described with reference to the drawings in the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, but not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art fall within the protection scope of the present invention.

According to an embodiment of the present invention, a one-step forming process of an ankle and foot orthosis is provided.

As shown in FIG. 1, the one-step molding process of an ankle and foot orthosis according to an embodiment of the present invention includes: Step S101, manufacturing a mold and a pressure equalizing plate; Step S103, applying a composite prepreg on the mold, and applying the composite prepreg. The mold and the pressure equalizing plate after the composite prepreg are assembled to obtain an assembly; step S105, the assembly is sequentially subjected to a vacuum treatment and a curing process, wherein the curing process includes: putting the assembly into a pressure tank , Pressurizing to the first preset pressure; heating the assembly to the first preset temperature according to the preset first temperature gradient, and maintaining the heat for the first time period; step S107, demolding the assembly, To get an ankle and foot orthosis.

With the help of the above technical solution, a mold and a pressure equalizing plate are manufactured, and then the composite prepreg is laid on the mold, and the mold and the pressure equalizing plate after the composite prepreg is applied are assembled to obtain an assembly, and then The assembly is vacuumed and cured in sequence. The curing process includes: placing the assembly in a pressure tank and pressurizing it to a first preset pressure; and according to a preset first temperature gradient, the assembly It is heated to the first preset temperature and kept warm for the first period of time. Finally, the assembly is demoulded to obtain an ankle and foot orthosis, which can save costs and increase production value. It is cured with the existing two-step curing process. Compared with molding, the improved one-step molding process saves half the amount of cans used in the autoclave, and in terms of materials, it saves the breathable felt, release film, PE film and vacuum used in the original first curing. At the same time, in terms of personnel, it also reduces the grinding process once, saving labor costs. In addition, it saves the bagging and demoulding work once by the paving staff, saving Time, improve work efficiency.

In order to better describe the technical solution of the present invention, detailed descriptions are provided below through specific embodiments.

As shown in FIG. 2, the steps of the one-step molding process of the ankle and foot orthosis include: step S21, first, cutting and laying of the prepreg; step S22, then pre-compacting the prepreg after being laid , It can pre-compact the prepreg after paving by assembling the mold; step S23, then packaging the assembled mold, if it can be packed into a vacuum bag, and then Vacuum treatment is performed by a vacuum pumping device; step S24, followed by curing treatment, for example, curing treatment at a curing temperature of 130 ° C and a pressure of 0.3 MPa; step S25, subsequent release treatment of the cured mold, and There is a grinding process; step S26, the finished product is tested.

In addition, the prepreg, adhesive film cutting, laying, pre-compacting, and packaging must be performed in a clean room. The room should be maintained at a temperature of 22 ± 4 ° C and a relative humidity of 30% to 65%. The cleanliness of the indoor air should reach Dust particles equal to and larger than 10 μm should not exceed 10 particles per liter. The positive pressure difference between indoor and outdoor should be 10 to 40 Pa. In addition, the curing temperature is 130 ° C and the pressure is 0.3 MPa. The temperature should be 15 ～ 32 ℃, the relative humidity should be less than 75%, and the room should be well ventilated. In addition, although the parameter range of the one-step molding process of the ankle and foot orthosis is shown above, those skilled in the art should It is understood that the parameter range can also be set according to actual needs. For example, according to an embodiment of the present invention, the curing temperature is 150 ° C., which is not limited in the present invention.

In addition, the equipment used for cutting, paving, pre-compacting, and packaging of prepregs and films include automatic feeders, ovens, and vacuum pumps. In addition, autoclaves are required for curing, and universal testing is required for grinding and inspection. Machine and sander.

In addition, as shown in FIG. 3, the forming mold includes a male mold 1 and a pressure equalizing plate 2. The pressure equalizing plate 2 has the same shape as the male mold 1 and can have a good fit with the male mold 1. A back surface of the pressure equalizing plate 2 is provided. Ground hole connected to male mold 1. In addition, the above-mentioned pressure-equalizing pressure equalizing plate 2 avoids bridging in the potholes during the pressurization process, resulting in a decrease in pressure transmission and defects such as pits on the surface of the product. In addition, the manufacturing process of the pressure equalizing plate 2 is cumbersome, and it cannot be turned directly on the mold because the size of the pressure equalizing plate is too small due to the problem of curvature between the molds, so it needs to be polished. On the end-of-life orthosis bracket. At the same time, the forming of the pressure equalizing plate 2 uses a hot press tank, the process temperature is 160 ° C., the time is 3 hours, and the pressure is 0.4 MPa. In addition, breathable felt can be applied to the surface of the equalizing plate 2 during the forming process, which is beneficial to improving the strength and hardness of the equalizing plate. In addition, those skilled in the art can set the size of the male mold 1 according to the required size of the ankle and foot orthosis, which is not limited in the present invention. In addition, because the barefoot orthosis has a large change in curvature of the shaped part in many positions of the product, which provides conditions for possible defects such as stress concentration and bridging, it is not enough to use soft compression alone. It is necessary to select a suitable compression soft mold according to the differences in the positions of the mold. For this reason, the invention adopts an overall soft mold method, which is different from the traditional soft mold flat plate. The soft mold sleeve eliminates the possibility of the above defects.

In order to better describe the technical solution of the present invention, it will be described in detail below with reference to FIG. 4 through three specific embodiments.

First embodiment

Referring to FIG. 4, in this embodiment, an opening for vacuum extraction is provided on the mold 1. The one-step molding process of the ankle and foot orthosis includes:

Step A: According to the shape of the product, a male mold 1 and a pressure equalizing plate 2 of the mold shown in FIG. 3 are manufactured;

Step B: Cut and lay the prepreg according to the requirements of the layup process on the male mold 1 with a release cloth;

Step C: Connect the pressure equalizing plate 2 and the male mold 1 through rivets to obtain an assembly. In addition, lay a breathable felt on the surface of the pressure equalizing plate in the assembly, and place the assembly in a vacuum bag, and The vacuum bag is connected to a vacuum pump, so that the vacuum pumping process is performed by the vacuum pump. For example, according to an embodiment of the present invention, under the condition of -0.95 Bar, at least 15 minutes are drawn, so that the Can remove air between male mold 1 and prepreg. In addition, of course, it can be understood that although this embodiment shows that the pressure equalizing plate 2 and the male mold 1 are connected by rivets, those skilled in the art may choose other active connection methods of the pressure equalizing plate 2 and the male mold 1 according to actual needs. The invention does not limit this;

Step D: heating the assembly to a first preset temperature according to a preset first temperature gradient, for example, according to an embodiment of the present invention, heating the mold to a preset temperature of 130 ° C at 1 ° C / min;

Step E: After putting the assembly into a pressurized tank, pressurize it to a first preset pressure. For example, according to an embodiment of the present invention, put the assembly into a pressurized tank and pressurize it to 0.3 MPa. And under the conditions of step D and step E, heat preservation and pressure retention for 120min;

Step F: The mold is heated according to the curing curve, the resin is cured, and the mold is removed.

In addition, in this embodiment, although the order of steps D and E is shown, those skilled in the art should understand that the order of steps D and E can be adjusted. For example, according to an embodiment of the present invention, The pressure treatment is performed first, and then the heat treatment is performed, and then under the conditions, the temperature is maintained for 120 minutes, which is not limited in the present invention.

In addition, in this embodiment, although the specific parameters of vacuum processing, heating and pressurizing are shown, those skilled in the art can set the above-mentioned parameters of vacuum processing, heating and pressurizing according to actual needs. The present invention This is not limited.

Second embodiment

In this embodiment, the molding process of the composite material product is basically the same as that of the first embodiment, except that the large steps will cause obvious stress concentration, which will cause the phenomenon of leg fracture in the later use of the product. Therefore, in step B, a change in the prepreg paving process is added to prevent excessive steps from appearing in the transition area and reduce the stress concentration at the transition. Referring to FIG. 4, the one-step molding process of the ankle and foot orthosis includes:

Step A: manufacturing the male mold 1 and the pressure equalizing plate 2 of the mold according to the shape of the product;

Step B: Cut and lay the prepreg according to the requirements of the layup process on the male mold 1 with a release cloth. In addition, the ankle and foot orthosis includes a tibial part and a foot part 4 connected to the tibial part. The inner surface is adapted to fit the human tibia, and the foot is used to receive the human foot. Wherein, the tibial portion is a prepreg obtained after demolding. Meanwhile, referring to FIG. 3, the transition region 5 and the intermediate turning region 6 in the tibial portion are thickened regions, and the gradation ply is used to thicken the transition region 5 and the intermediate turning region 6, that is, the transition region 5 And the middle turning area 6 has a plurality of layups that gradually change in size from the bottom layer to the top layer, so that the thickness of the transition area 5 and the middle turning area 6 is uniform and the transition at the surface is uniform;

Third embodiment

In this embodiment, the molding process of the composite material product is basically the same as that of the first embodiment, except that the temperature gradient is added in step D, and the temperature is maintained and maintained according to the temperature gradient, so that the resin is further improved during the curing stage. The degree of infiltration can make the product more compact and manufacture products with complex structures. Referring to FIG. 4, the one-step molding process of the ankle and foot orthosis includes:

Step B: Cut and lay the prepreg according to the requirements of the layup process on the male mold 1 with a release cloth. Also referring to FIG. 3, the transition region 5 and the intermediate turning region 6 at the tibial portion are thickened regions, and the transitional layer 5 and the intermediate turning region 6 are thickened by a gradual lamination method so that the transition region 5 and the intermediate turning region 6 are thickened. The thickness is uniform and the transition at the surface is uniform;

Step D: heating the assembly to a first preset temperature according to a preset first temperature gradient, and heating the assembly to a second preset temperature according to a preset second temperature gradient, and in a second time period Internal thermal insulation and pressure retention, for example, according to an embodiment of the present invention, the mold is heated to a preset temperature of 50 ° C at 1 ° C / min, and maintained for 60 minutes, and the mold is heated to a preset temperature of 130 ° C at 1 ° C / min. Pressure for 120min;

Embodiment 4:

In this embodiment, the molding process of the composite material product is basically the same as the above-mentioned second embodiment, except that in step D, a defoaming process is added, and repeated vacuum-air defoaming technology is used. Reduce air bubbles between prepreg layers to ensure product quality. The one-step forming process of the ankle and foot orthosis includes:

Step D: After putting the assembly into a pressure tank, pressurize it to a first preset pressure, and heat the assembly to a first preset temperature according to a preset first temperature gradient, and step A The pressure drop in the pressure tank is zero, and the pressure tank is evacuated in the third period, and the air is introduced into the pressure tank in the fourth period, and the above step A is repeated until the execution The number of times is the same as the preset number, then the cycle is stopped, and then the pressure is increased to the second preset pressure, and the assembly is heated to the third preset temperature according to the preset third temperature gradient, and within the third time period For example, according to an embodiment of the present invention, after putting the assembly into the autoclave, the air temperature is set to 50 ° C, and the heating rate is set to 1 ° C / min. After the tank door is closed, it starts at the same time. Pressurize and heat up, and count the time. After 20 minutes, release the pressure to 0 first, and then open the air to 15min after vacuuming for 10min, then perform a second vacuum for 10min and then open the atmosphere for 15min, and then after the third vacuum Open the atmosphere for more than 15min in the above three cycles , Vented to atmosphere, the set pressure 0.3MPa, the set air temperature of 135 deg.] C, heating rate was set to 2 ℃ / min, and began pressurized and heated to the timing when the temperature reaches 130 ℃, holding 2H;

Step E: The mold is heated according to the curing curve, the resin is cured, and the mold is removed.

In addition, after passing through the first embodiment, the second embodiment, the third embodiment, or the fourth embodiment, a tibial portion is obtained, and then the tibial portion and the foot are combined to obtain an ankle and foot orthosis. The finished ankle and foot orthosis is then tested. The testing process is as follows:

Test method: Fix the foot of the product with a steel fixture, press with a steel pressure plate, apply a load rod to the produced tibia, and load the point at a distance of 100mm from the foot;

Test parameters: preload is 10N, record the load value when the deformation is 10mm;

Test equipment: universal testing machine;

Test standard: small (S): load range 300-406N when the deformation is 10mm, the ratio is 30-40.6N / mm; medium (M): load range 314-425N when the deformation is 10mm, the ratio is 31.4- 42.5N / mm; Large (L): Load range is 344-465N when the deformation is 10mm, and the ratio is 34.4-46.5N / mm.

According to an embodiment of the present invention, an ankle and foot orthosis is also provided.

In summary, by means of the above technical solution of the present invention, by manufacturing a mold and a pressure equalizing plate, and then laying the composite prepreg on the mold, and performing the mold and the pressure equalizing plate after applying the composite prepreg. Assemble to obtain the assembly, and then vacuum and cure the assembly in sequence. The curing process includes: putting the assembly into a pressure tank, pressurizing to a first preset pressure; according to the preset A first temperature gradient, which heats the assembly to a first preset temperature and insulates it for a first period of time, and finally performs a demolding process on the assembly to obtain an ankle and foot orthosis, which can save costs and increase production value. Compared with the existing two-step curing molding, the improved one-step molding process saves half the amount of cans in the use of the autoclave, and in terms of materials, it saves the breathable felt used in the original first curing. , Isolation film, PE film and vacuum bag, etc. At the same time, in terms of personnel, it also reduces the one-time grinding process, saving labor costs, in addition, it also saves the shoppers to pack the bag once. Stripping work, saving time and increasing efficiency.

The above are only the preferred embodiments of the present invention and are not intended to limit the present invention. Any modification, equivalent replacement, or improvement made within the spirit and principle of the present invention shall be included in the present invention. Within the scope of protection.

Claims

A one-step forming process for an ankle and foot orthosis, which is characterized by comprising:

Step S1, manufacturing a mold and a pressure equalizing plate;

Step S2: laying a composite prepreg on the mold, and assembling the mold and the pressure equalizing plate after the composite prepreg is applied to obtain a composite part;

In step S3, the assembly is sequentially subjected to a vacuum treatment and a curing process, wherein the curing process includes:

After putting the assembly into a pressure tank, pressurizing it to a first preset pressure;

Heating the assembly to a first preset temperature according to a preset first temperature gradient, and maintaining heat for the first time period;

In step S4, the assembly is demoulded to obtain the ankle and foot orthosis.
The one-step molding process according to claim 1, wherein in step S2,

The composite prepreg is laid on the transition area of the mold in a gradual lamination manner.
The one-step molding process according to claim 1, wherein the curing process further comprises:

Heating the assembly to a second preset temperature according to a preset second temperature gradient, and maintaining heat and pressure for a second period of time.
The one-step molding process according to claim 1, wherein the curing process further comprises:

Repeat the following steps: reduce the pressure in the pressurized tank to zero, and evacuate the pressurized tank in the third time period, and in the fourth time period, go to the pressurized tank Let in air

Until the execution times are the same as the preset times, the loop is stopped;

Pressurize to a second preset pressure, and heat the assembly to a third preset temperature according to a preset third temperature gradient, and maintain heat and pressure for a third period of time.
The one-step forming process according to claim 1, wherein the evacuation process comprises:

The assembly is placed in a vacuum bag, and the vacuum bag is connected to a vacuum pump, so that the vacuum processing is performed by the vacuum pump.
The one-step molding process according to claim 1, wherein performing demolding treatment on the assembly to obtain the ankle and foot orthosis comprises:

Demoulding the assembly to obtain a tibia portion, and the inner surface of the tibia portion is used to fit the tibia of the human body;

The tibial portion and the foot receiving the foot are combined to obtain the ankle-foot orthosis.
The one-step molding process according to claim 1, wherein the step S2 further comprises: laying a breathable felt on a surface of the pressure equalizing plate in the assembly.
The one-step molding process according to claim 7, wherein during the step S1 of manufacturing the pressure equalizing plate,

The breathable felt is applied on the surface of the pressure equalizing plate, so as to obtain a pressure equalizing plate having the breathable felt.
The one-step molding process according to claim 1, wherein in step S2,

A release agent and the composite prepreg are sequentially laid on the mold.
An ankle and foot orthosis, characterized in that the ankle and foot orthosis is made by a one-step molding process of the ankle and foot orthosis according to any one of claims 1-10.