RU2404203C1 - Device for shaping parts from polymer composite material - Google Patents

Abstract

FIELD: machine building.

SUBSTANCE: device for shaping parts from polymer composite material includes support system 1 consisting of a set of longitudinal walls 9 connected with transverse walls 8, and shaping surface installed on support structure - by means of point supports - locking members 5, located on ends of transverse walls 8 taking the shape of inner side of shaping surface and compensating its inaccuracies.

EFFECT: invention allows developing the design of device for shaping of thin-wall parts with complex geometric shape which would allow quality product without deformation and distortions, thus keeping the specified geometric shapes, and with high strength and reliability characteristics.

4 cl, 4 dwg

Description

Technical field

The invention relates to the field of plastic processing by shaping by coating the mold, namely, snap-ins for molding multilayer parts from a polymer composite material (PCM), and can be used in the manufacture of parts for aircraft and machine building.

State of the art

A device for the vacuum-autoclave molding of structural panels of polymer composite materials (PCM) is known / RF patent 2106251 C1, class B29C 43/20, 1998 / According to the patent, the tool has a base in the form of rods horizontally located along the forming shell, on which the ability to move installed lodgements. The forming shell is fixed on the lodges by means of adjustable supports with the formation of a guaranteed gap between the forming shell and the lodges.

The disadvantage of this device is the need for fastening the forming shell to the lodgements with a screw connection. This creates the possibility of violation of the tightness of the forming tool due to the difference in the coefficients of linear thermal expansion (KLTR) or relative sizes between the fastener element and the forming tool, which leads to poor-quality parts, and the manufacture of such equipment is very time-consuming.

Closest to the proposed device in terms of technical nature and technical solution is a tool for molding products from a polymer composite material / according to the patent of the Russian Federation 2090364 C1 class В29С 43/20, 1997 /, according to which the tooling for molding contains a support system and a forming system fixed to it shell. The support system contains

- lodgements made in the form of a set of hollow V-shaped sections spaced across the width of the shell with support legs and open ends pulled together by stiffeners spaced along the length of the profiles;

- Compensators of curvature located between the mating surfaces of the profiles and forming equipment.

The disadvantage of this invention is that the equipment does not allow to obtain the required uniformity of temperature distribution over the entire volume of the furnace, since continuous V-shaped profiles have solid walls that impede free circulation, which leads to the formation of stagnant zones and a large temperature difference in the volume of the furnace chamber.

SUMMARY OF THE INVENTION

The objective of the present invention is to provide a design tooling for forming thin-walled parts of complex geometric shape from PCM, which would allow to obtain a high-quality product without warping and leashes, while maintaining the specified geometric shapes, as well as high characteristics of strength and reliability.

The problem is solved due to the fact that in the snap-in for molding parts from PCM, made in the form of a support system and a forming surface for laying out the prepreg package, the forming surface is mounted on the support system using point support latches that take the shape of the wrong side of the forming surface and compensate for it inaccuracies. The point support-clamp is made in the form of a bracket rigidly fixed to the longitudinal wall of the support system having a shelf carrying a pillow of the point support-clamp made of heat-resistant uncured plastics based on cold-cured resins.

The point support-latch can be made in the form of an adjustable, containing bracket, rigidly fixed to the longitudinal wall, support system. The bracket has a glass into which a screw is screwed to an adjustable height, which carries a cushion of a point support-clamp made of heat-resistant uncured plastics based on cold-cured resins.

In addition, the longitudinal walls of the support system, intended for installation on the support surface, are made with a higher height, and the transverse walls are raised relative to the lower edge of the longitudinal walls and installed with a gap, forming a space in the lower part of the support system.

This solution to the problem allows you to get a quality product without warping and leash, while maintaining the specified geometric shapes, and accordingly high characteristics of strength and reliability.

The device is illustrated by drawings, in which:

Figure 1 shows a general view of a tooling for molding PCM parts with a prepreg package placed on it (front view).

Figure 2 shows a General view of the tooling for forming parts from RMB (side view).

Figure 3 shows the node A of figure 2.

Figure 4 shows an adjustable point support latch.

The implementation of the invention

The tooling for molding PCM parts includes (Fig. 1) a support system 1, a forming surface 2 for laying out the prepreg package 3, point support latches 5, consisting of an arm 6 and a cushion of point support 7.

The transverse walls 8 of the support system are made with a gap relative to the forming surface 2, thereby forming channels 4.

The support system 1 (Fig. 1) consists of a set of longitudinal walls 9 connected by transverse walls 8 into a rigid frame along the entire width of the forming surface 2. The longitudinal walls 9 are designed to be mounted on the supporting surface, the transverse walls 8 are raised relative to the lower edge of the longitudinal walls 9 and installed with a gap, i.e. forming a space for the passage of hot air in the lower part of the support system 1. The longitudinal and transverse walls are made of fiberglass impregnated with cold cured resin by contact molding or vacuum molding. This material has a low heat capacity and sufficient mechanical strength.

The thickness of the longitudinal and transverse walls is 5-10 mm.

The forming surface 2 is made thin-walled from the same materials as the walls of the support system. The geometry and construction height of the forming surface is set using the master model. The construction height of the forming surface is 140 mm. A matrix gel coat is applied to the front of the forming surface. The thickness of the forming surface is 8 mm. The selected thickness and construction height for this material provide the necessary rigidity of the forming surface. The forming surface is mounted on the support system with the help of point support latches 5 located on the transverse walls 8 of the support system (figure 2). Point support clamps are located at the ends of the transverse walls 8 between the mating surfaces of the transverse walls and the forming surface 2. The point support clamp 5 (Fig. 3) is made in the form of an arm 6 made of the same material as the walls of the support system. The bracket 6 is mounted on the longitudinal wall 9 with screws 10 and has a shelf carrying a cushion 7 of a point support-retainer. The point support pad is made of uncured plastics based on cold cured resins, which are heat resistant at product molding temperatures (e.g. + 200 ° C). During curing, the material of the cushion 7 of the point support-clamp easily assumes the shape of the wrong side of the forming surface 2, thereby ensuring a snug fit to the wrong side of the forming surface and acting as curvature compensators. Also, in the process of curing the pads 7 of the point support-retainer, the forming surface 2 is glued - fixed to the point support-retainer. The height of the point support-latch 5 is calculated in such a way as to ensure the guaranteed height of the channel 4 for the movement of heated air flows (20 mm minimum). The area in the places of contact of the cushion 7 of the point support to the forming surface 2 should not exceed 2 cm ² .

Depending on the load on the forming surface and the complexity of its geometric shape, the number of point support-clamps can increase to the amount necessary to create a given structural rigidity of the forming surface. But at the same time, the point supports should be positioned in such a way as to guarantee the presence of a channel for the circulation of hot air flows and the minimum contact area of the point support with the forming surface.

The point support-latch can be made adjustable (figure 4). At the ends of the transverse walls 8 between the mating surfaces of the transverse walls 8 and the forming surface 2 are installed adjustable point supports-clamps (figure 4). The adjustable point support-latch is made in the form of an arm 11 and a cushion 7 of a point support. The bracket 11 is mounted on the longitudinal wall with screws. A glass 12 is installed in the bracket of the point support, into which a bolt 13 is carried to an adjustable height, which carries the pillow 7 of the point support described above.

The channel in the proposed invention (figure 1) is formed between the forming surface 2 and the upper edge of the transverse walls 8 of the support system.

The operation of the device is as follows.

On the forming surface 2 lay the prepreg package 3, then the prepreg package is hermetically sealed with a film. A vacuum is created under the film, and the film seals the prepreg bag.

Equipment with a prepreg package located on it is placed in a thermal furnace, where the prepreg material is held at a certain temperature until the curing process is completed.

Channel 4 is located under the forming surface and provides unhindered circulation of hot air flows, uniformly heating the forming surface and, accordingly, the entire prepreg package located on it.

Upon completion of the required curing cycle, the sealing film is removed, the equipment and the product are cooled at room temperature. The finished product is removed from the forming surface of the snap.

Also, the curing process using the above equipment can be carried out in an autoclave.

Due to the fact that the forming surface is mounted on the support system using point support latches (with the possibility of regulation) with a minimum contact area, a uniform heat supply to the prepreg package is ensured, which allows to obtain a high-quality part. This design snap allows you to reduce its cost.

Claims (4)

1. Tooling for molding parts from a polymer composite material, comprising a support system and a forming surface, characterized in that the support system consists of a set of longitudinal walls and connected by transverse walls, and the forming surface is mounted on the support system using point support latches located at the ends of the transverse walls, taking the form of the wrong side of the forming surface and compensating for its errors. 2. A tool for molding parts from a polymer composite material according to claim 1, characterized in that the point support-lock is made in the form of a bracket rigidly mounted on the longitudinal wall of the support system having a shelf carrying a pillow of the point support-clamp made of heat-resistant, uncured plastics based on cold cured resins. 3. Tooling for molding parts from a polymer composite material according to claim 1, characterized in that the adjustable point support-latch is made in the form of a bracket rigidly fixed to the longitudinal wall of the support system having a glass into which a screw carrying a pad is screwed onto an adjustable height point support-clamp made of heat-resistant uncured plastics based on cold cured resins. 4. Tooling for molding parts from a polymer composite material according to claim 1, characterized in that the transverse walls are raised relative to the lower edge of the longitudinal walls and installed with a gap, forming a space in the lower part of the support system.

Images