Mold assembly for resin transfer molding

Patent metadata

Field	Value
Publication number	US-10994504-B2
Application number	US-201715599061-A
Country	US
Kind code	B2
Filing date	May 18, 2017
Priority date	May 19, 2016
Publication date	May 4, 2021
Grant date	May 4, 2021

Abstract

A mold assembly includes an injection mold configured to receive a woven preform. The preform has a principal direction with at least one edge extending substantially along the principal direction. The mold assembly is configured to allow the impregnation of the preform with a resin injected into the mold. The mold assembly further includes a removable longitudinal element for the injection mold, wherein said longitudinal element is configured to cooperate with the preform and conformed as a profiled member configured to be arranged in contact with the mold along at least the segment of the edge of the preform in order to prevent the pinching of free fibers extending from the edge of the preform between the two parts of the mold.

First claim

The invention claimed is:

1. A mold assembly comprising an injection mold having at least two parts, the mold configured to move between an open position in which said at least two parts are separated to allow the introduction of a preform in its entirety into a cavity of the at least one of said two parts, and a closed position in which said at least two parts are joined along a parting line to allow the impregnation of said preform with a resin injected into said mold, and then the polymerization of the resin impregnating said preform, said preform extending in a given principal direction, comprising at least one edge extending substantially along said principal direction in a vicinity of lateral edges of the cavity, and said edge comprising at least one segment from which there project free fibers liable to lie in the parting line of said two parts of said mold when it occupies its closed position, and at least one longitudinal element adapted to said injection mold, wherein said at least one longitudinal element is removable, configured so as to cooperate with the preform and conformed as a profiled member, and configured so as to be arranged in contact with said mold along at least said segment of said edge of the preform in order to prevent the pinching of the free fibers of said segment of said edge of the perform between said at least two parts of said mold, wherein the mold comprises a bottom part comprising a pattern configured so as to receive the preform and comprising at least a first mold closure face, a top part configured so as to close the bottom part and comprising at least one second mold closure face able to cooperate with the first face, said first and second faces being configured so as to be arranged in contact with each other along the whole of their surfaces along said at least one parting line in the closed position of the mold, and wherein said at least one removable element is configured so as to be disposed in contact with a wall of the pattern and at said parting line providing a junction of the bottom and top parts of the mold.

2. The mold assembly according to claim 1 , wherein said at least one longitudinal element has an L-shaped cross section and comprises a wall that is configured so as to be placed in contact with a wall of one of the at least two parts of the mold before the mold is closed and a wall that is configured so as to be arranged in contact with a facing wall of another of the at least two parts of the mold when the mold is closed.

3. The mold assembly according to claim 2 , wherein the walls of said at least one longitudinal element are configured so as to extend on either side of the edge of the preform at a minimum distance able to contain the free fibers of said segment of the edge of the preform projecting from said segment.

4. The mold assembly according to claim 2 , wherein said at least one longitudinal element is configured so as to cooperate with a preform comprising at least a first part comprising said edge, intended to be removed by machining after polymerization of said preform, and at least a second part intended to form a final component, and in that the walls of said at least one longitudinal element are configured so as to extend only facing said first part.

5. The mold assembly according to claim 1 , wherein the edge of the perform has a given profile and in that a profile of said at least one longitudinal element configured as a profiled member follows the profile of the edge of the preform along the entire length of said at least one longitudinal element.

6. A manufacturing method for manufacturing a turbine-engine component made from composite material by impregnating a woven preform with a resin with a mold assembly according to the claim 1 , characterized in that the method comprises successively:
a step during which a three-dimensional weaving of fibers is carried out;
a step during which the weave is cut in order to obtain a preform corresponding substantially to the component to be obtained, said preform comprising at least one edge, at least one segment of which comprises free fibers;
a step during which the preform is deposited in the pattern in the bottom part of the mold;
a step during which at least one longitudinal element, which is removable, is deposited in contact with a wall of the pattern along at least said segment of the edge of the preform and at the parting line of the mold providing the junction of its bottom and top parts;
a step during which the top part of the mold is closed on the bottom part;
a step during which resin is injected into the mold;
a step of polymerization of the resin;
a step during which the preform and the at least one longitudinal element trapped in the polymerized resin are extracted; and
a step during which a first part of the preform containing the at least one longitudinal element trapped in the polymerized resin is machined in order to eliminate said at least one longitudinal element and any excess resin in order to keep only a second part of the preform corresponding to the final component.

7. The manufacturing method according to claim 6 , wherein the walls of said at least one longitudinal element are configured so as to extend on either side of the edge of the preform at a minimum distance able to contain the free fibers of said segment of the edge of the preform projecting from said segment, and wherein said at least one longitudinal element is configured so as to cooperate with a preform comprising at least a first part comprising said edge, intended to be removed by machining after polymerization of said preform, and at least a second part intended to form a final component, and in that the walls are configured so as to extend only facing said first part, and wherein the edge of the perform has a given profile and in that a profile of said profiled member follows the profile of the edge of the preform along the entire length of said profiled member, the method comprising, prior to the step of depositing the removable element, a step during which said at least one longitudinal element is chosen from a stock of removable elements so that:
a profile of the profiled member of said at least one longitudinal element follows the profile of the edge of the preform along the entire length of said profiled member,
the walls of the profiled member of said at least one longitudinal element are configured to extend on either side of the edge of the preform along a minimum distance able to contain the free fibers of said segment of the preform extending from said segment, and
the walls of the profiled member of said at least one longitudinal element are configured to extend only in line with said first part of the preform.

8. A mold assembly comprising an injection mold having at least two parts, the mold configured to move between an open position in which said at least two parts are separated to allow the introduction of a preform into at least one of said parts, and a closed position in which said at least two parts are joined along a parting line to allow the impregnation of said preform with a resin injected into said mold, and then the polymerization of the resin impregnating said preform, said preform extending in a given principal direction, comprising at least one edge extending substantially along said principal direction, and said edge comprising at least one segment from which there project free fibers liable to lie in the parting line of said two parts of said mold when it occupies its closed position, and at least one longitudinal element adapted to said injection mold, wherein said at least one longitudinal element is removable, configured so as to cooperate with the preform and conformed as a profiled member, and configured so as to be arran

Assignees

• Safran Aircraft Engines

Inventors

• Techer Marc-Emmanuel Jean Franĉois
• Ashtari Nicolas Cambyse
• Six Pauline Nathalie

Classifications

• B29C70/541 Primary

  Positioning reinforcements in a mould, e.g. using clamping means for the reinforcement (positioning inserts in moulds B29C33/12; lay-up on a mould B29C70/30) · CPC title

• B29C70/54 Primary

  Component parts, details or accessories; Auxiliary operations {, e.g. feeding or storage of prepregs or SMC after impregnation or during ageing} · CPC title

• B29D99/0025

  Producing blades or the like, e.g. blades for turbines, propellers, or wings · CPC title

• B29C70/543

  Fixing the position or configuration of fibrous reinforcements before or during moulding (for non-woven fabrics D04H3/08) · CPC title

• B29C67/248

  Moulding mineral fibres or particles bonded with resin, e.g. for insulating or roofing board (articles from wood or lignocellulosic material with binding agents B27N; mineral aggregates bonded with resin B29C67/242; thermal insulation in general F16L59/00) · CPC title