CN112297473A - Forming die for composite material elongated box-shaped beam with negative angle on one side - Google Patents
Forming die for composite material elongated box-shaped beam with negative angle on one side Download PDFInfo
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- CN112297473A CN112297473A CN202011076081.5A CN202011076081A CN112297473A CN 112297473 A CN112297473 A CN 112297473A CN 202011076081 A CN202011076081 A CN 202011076081A CN 112297473 A CN112297473 A CN 112297473A
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- die
- box
- forming
- male die
- negative angle
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
- B29C—SHAPING OR JOINING OF PLASTICS; SHAPING OF MATERIAL IN A PLASTIC STATE, NOT OTHERWISE PROVIDED FOR; AFTER-TREATMENT OF THE SHAPED PRODUCTS, e.g. REPAIRING
- B29C70/00—Shaping composites, i.e. plastics material comprising reinforcements, fillers or preformed parts, e.g. inserts
- B29C70/04—Shaping composites, i.e. plastics material comprising reinforcements, fillers or preformed parts, e.g. inserts comprising reinforcements only, e.g. self-reinforcing plastics
- B29C70/28—Shaping operations therefor
- B29C70/54—Component parts, details or accessories; Auxiliary operations, e.g. feeding or storage of prepregs or SMC after impregnation or during ageing
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
- B29C—SHAPING OR JOINING OF PLASTICS; SHAPING OF MATERIAL IN A PLASTIC STATE, NOT OTHERWISE PROVIDED FOR; AFTER-TREATMENT OF THE SHAPED PRODUCTS, e.g. REPAIRING
- B29C33/00—Moulds or cores; Details thereof or accessories therefor
- B29C33/10—Moulds or cores; Details thereof or accessories therefor with incorporated venting means
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
- B29C—SHAPING OR JOINING OF PLASTICS; SHAPING OF MATERIAL IN A PLASTIC STATE, NOT OTHERWISE PROVIDED FOR; AFTER-TREATMENT OF THE SHAPED PRODUCTS, e.g. REPAIRING
- B29C33/00—Moulds or cores; Details thereof or accessories therefor
- B29C33/30—Mounting, exchanging or centering
- B29C33/303—Mounting, exchanging or centering centering mould parts or halves, e.g. during mounting
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
- B29L—INDEXING SCHEME ASSOCIATED WITH SUBCLASS B29C, RELATING TO PARTICULAR ARTICLES
- B29L2031/00—Other particular articles
- B29L2031/30—Vehicles, e.g. ships or aircraft, or body parts thereof
- B29L2031/3076—Aircrafts
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- Engineering & Computer Science (AREA)
- Mechanical Engineering (AREA)
- Chemical & Material Sciences (AREA)
- Composite Materials (AREA)
- Moulds For Moulding Plastics Or The Like (AREA)
Abstract
The invention relates to a forming die for a composite material elongated box-shaped beam with a negative angle on one side, and belongs to the technical field of autoclave forming. A forming die for a composite material elongated box-shaped beam with a negative angle on one side comprises a beam forming die and a beam uniform pressure plate forming die, wherein a die attaching surface of the beam forming die is an inner molded surface of the box-shaped beam and is used for forming the box-shaped beam, and a die attaching surface of the beam uniform pressure plate forming die is an outer molded surface of the box-shaped beam and is used for forming a uniform pressure plate of the box-shaped beam; the beam forming die comprises a male die I, a male die II and a bottom support. The invention has the following advantages: 1. the precision of the die is ensured, the manufacturing difficulty of the die is reduced, and the production efficiency is improved; 2. the problems that the box-shaped beam is difficult to position and form at a negative angle are solved; 3. the slotting is convenient for workshop workers to take the box-shaped beam out of the die; 4. the grooves and the ventilation grooves are lightened, so that the quality of the male die is ensured; 5. the forming qualification rate of the box-shaped beam is improved.
Description
Technical Field
The invention relates to a forming die for a composite material elongated box-shaped beam with a negative angle on one side, and belongs to the technical field of autoclave forming.
Background
As an advanced material, the composite material is widely applied to the fields of aviation, aerospace and civil life due to high specific strength and modulus, excellent fatigue resistance, chemical corrosion resistance, low expansion performance and the like. The upper beam of the airplane is used as one of main bearing structures, and the structural forms of the upper beam of the airplane comprise a I-shaped beam, a J-shaped beam, an I-shaped beam, a box-shaped beam and the like. The parts such as the beam are internal components of large parts of the airplane, and after the parts such as the beam are finished, a gluing process with other parts of the airplane exists, so that the shape change of the beam needs to be strictly controlled in the manufacturing process. The importance of the mold to the manufacture of the composite material member is self-evident. The mold for the composite material member must be specifically combined for different objects from material selection to structural design. A box beam about 2600mm in length, 162mm in width and 72mm in height is a typical long span elongated box beam with a large negative angle in one side profile of the box beam (see fig. 1 and 2). According to the requirements of the structure and precision of the beam, the design of the box-shaped beam forming die has certain complexity and processing difficulty, and the molded surface of the long and thin box-shaped beam is easy to deform in the forming process, so that the surface quality and the assembly precision of the beam are influenced. When forming such an elongated box beam, the mold structure should be designed reasonably, not only considering the deformation condition and the uniformity of heat and pressure transmission during the beam forming process, but also paying attention to whether the beam is easy to be taken out from the mold after being formed.
Disclosure of Invention
The invention aims to solve the problems in the prior art and provide the forming die of the composite material elongated box-shaped beam with the negative angle on one side, which can reduce the manufacturing difficulty of the die, ensure the die precision and improve the production efficiency.
In order to achieve the purpose, the invention adopts the following technical scheme: a forming die for a composite material elongated box-shaped beam with a negative angle on one side comprises a beam forming die and a beam uniform pressure plate forming die, wherein a die attaching surface of the beam forming die is an inner molded surface of the box-shaped beam and is used for forming the box-shaped beam, and a die attaching surface of the beam uniform pressure plate forming die is an outer molded surface of the box-shaped beam and is used for forming a uniform pressure plate of the box-shaped beam; the beam forming die comprises a male die I, a male die II and a bottom support, parting surfaces of the male die I and the male die II are perpendicular to the bottom support, the bottom support is used as a bottom surface for forming the box-shaped beam, and the male die I and the male die II are positioned on the bottom support and are manufactured separately from the bottom support.
Preferably, the convex die II is close to one side of the negative angle, the bottom of the convex die II is provided with a groove, a convex positioning block is fixed on the bottom support, and the groove is matched with the convex positioning block and is in contact positioning with the convex positioning block.
Preferably, a wedge-shaped block is arranged on one side of the male die II and used for positioning the side face of the male die II.
Preferably, be provided with a plurality of lightening grooves in I inside terrace die, lighten the length direction evenly distributed of groove along I main part of terrace die, its opening is towards the bottom sprag.
Preferably, the connecting rib plate between the adjacent lightening grooves is provided with a ventilation groove.
Preferably, the male die I is far away from the negative angle side, and a part edge line is arranged on the main body of the male die I along the length direction of the male die I and is used as an edge reference line of the box-shaped beam.
Preferably, a plurality of grooves are formed below the edge line of the part and are uniformly distributed along the length direction of the male die I body.
Preferably, the base support is a frame structure.
Preferably, the main body structures of the beam forming die and the beam uniform pressure plate forming die are consistent.
Two sets of dies are provided for forming the composite material elongated box-shaped beam with a negative angle on one side, and the two sets of dies are respectively a beam forming die and a beam pressure equalizing plate forming die. The uniform pressure plate is made of uniform materials by pressing, the beam uniform pressure plate forming die is used for forming the uniform pressure plate of the beam, and the forming surface is the outer profile of the beam and is used for manufacturing the uniform pressure plate made of the glass fiber reinforced plastic material with the same thickness of about 12 mm; the beam forming die is used for forming the box-shaped beam, and the formed pressure equalizing plate is placed on the surface of the beam and used for controlling the surface quality and the thickness of the beam. The main structure of the beam uniform pressure plate forming die is consistent with that of the beam forming die, the die attaching surface of the beam uniform pressure plate forming die is an outer molded surface of the beam, and the die attaching surface of the beam forming die is an inner molded surface of the beam.
Compared with the prior art, the invention has the following advantages:
1. the male die and the frame structure are manufactured in a split mode and then welded, so that the die precision is guaranteed, the die manufacturing difficulty is reduced, and the production efficiency is improved;
2. the male die is divided into two parts, and a convex positioning block is adopted for positioning, so that the problems that the negative angle of the box-shaped beam is difficult to position and form are solved;
3. a notch is formed in the male die I, so that a workshop worker can conveniently take the box-shaped beam out of the die;
4. the male die I is provided with the lightening groove and the ventilating groove, so that air circulation and uniform heating and pressing of the die are guaranteed in the forming process of the die, the weight of the die is lightened, and the quality of the male die is guaranteed;
5. the surface quality and the thickness of the box-shaped beam are effectively controlled, and the forming qualification rate of the box-shaped beam is improved.
Drawings
FIG. 1 is an isometric view of a box beam 1 according to an embodiment of the invention;
FIG. 2 is an isometric view 2 of a box beam in an embodiment of the invention;
FIG. 3 is an isometric view of an embodiment of the present invention;
FIG. 4 is an isometric view of an embodiment of the invention (without a wedge);
FIG. 5 is an isometric view of a frame and a male locating block in an embodiment of the invention;
FIG. 6 is an isometric view of a punch II and a locating boss according to an embodiment of the present invention;
FIG. 7 is an isometric view of punch II in an embodiment of the invention;
FIG. 8 is an isometric view of punch I in an embodiment of the invention;
FIG. 9 is an isometric view of a vent slot in a punch I according to an embodiment of the invention;
FIG. 10 is a schematic view of the caul plate being placed in the beam forming mold;
in the figure, 1, frame; 2. a wedge block; 3. a male die II; 4. a male die I; 5. Slotting; 6. a part edge line; 7. a convex positioning block; 8. a relief groove; 9. and (4) ventilating slots.
Detailed Description
The technical solutions of the present invention will be described clearly and completely with reference to fig. 1 to 9, and it should be understood by those skilled in the art that the described embodiments are a part of the embodiments of the present invention, but not all of the embodiments. All other embodiments obtained without inventive work on the basis of the embodiments of the present invention fall within the scope of protection of the present invention.
A forming die for a composite material elongated box-shaped beam with a negative angle on one side is provided, wherein two sets of dies are provided for forming the composite material elongated box-shaped beam with the negative angle on one side, and the two sets of dies are a beam forming die and a beam pressure equalizing plate forming die respectively. The uniform pressure plate is made of uniform materials through pressing, the beam uniform pressure plate forming die is used for forming the uniform pressure plate of the beam, and the forming surface is the outer profile of the beam and is used for manufacturing the uniform pressure plate made of the glass fiber reinforced plastic materials with the same thickness of about 12 mm. The beam forming mold is used for forming the box-shaped beam, and the formed pressure equalizing plate is placed on the surface of the beam (as shown in fig. 10, the beam forming mold, the paved beam and the pressure equalizing plate are arranged from inside to outside in sequence) and used for controlling the surface quality and the thickness of the beam. The main structures of the beam pressure equalizing plate die and the beam forming die are consistent, and the only difference is that the die attaching surface of the beam pressure equalizing plate die is the outer profile of the beam, and the die attaching surface of the beam forming die is the inner profile of the beam (the die attaching surface is the forming profile of the male die I and the male die II which are mentioned next). Therefore, the structure of the die will be described below by taking a beam forming die as an example.
As shown in fig. 1 to 4, a beam forming mold for forming a composite material elongated box-shaped beam having a negative angle on one side thereof is mainly composed of a frame 1, a male mold i 4, a male mold ii 3, a wedge block 2, and a convex positioning block 7. Due to the large size span of the box beam (as shown in fig. 1-2), a frame type structure is adopted in order to make the box beam heated and pressed quickly and uniformly in the forming process. The box-shaped beam is formed by adopting a male die, so that the male die and the frame 1 are manufactured in a split mode and then welded, the precision of the die is guaranteed, the manufacturing difficulty of the die is reduced, and the production efficiency is improved. Because one end of the beam has a negative angle, the male die is divided into two parts: the die comprises a male die I4 and a male die II 3, and the parting surfaces of the male die I4 and the male die II 3 are guaranteed to be perpendicular to the bottom surface (the frame 1) of the die.
As shown in fig. 5-7, the convex positioning block 7 is welded on the frame 1 for positioning, the male die ii 3 is provided with a groove, the groove is matched with the convex positioning block 7, the male die ii 3 is positioned by the contact of the convex positioning block 7, the surface a and the surface B position two surfaces of the male die ii 3 and the convex positioning block 7 respectively, the side surface of the male die ii 3 is positioned by the wedge block 2, and the other surface (surface C) of the male die ii 3 is positioned by the contact of the surface i 4 (surface C) of the male die, so that the male die ii 3 is positioned completely.
As shown in fig. 8-9, the male die i 4 is provided with a slotting 5, a part edge line 6, a lightening groove 8 and a ventilating groove 9, wherein the part edge line 6 is arranged on the main body of the male die i and extends along the length direction of the main body to be used as an edge reference line of a beam paved with box-shaped beams; in order to facilitate workshop workers to take the box-shaped beam out of the die, a notch 5 is formed below the edge line 6 of the part, and the notch 5 is a kidney-shaped groove and is uniformly distributed along the length direction of the main body of the male die I; because the size span of the box-shaped beam is large, in order to ensure that the box-shaped beam is heated and pressed quickly and uniformly in the forming process and also to reduce the weight of the die, lightening grooves 8 are uniformly formed in the male die I4, the lightening grooves 8 are uniformly distributed along the length direction of the main body of the male die I, and the openings of the lightening grooves face the frame 1; because the mould is heated and is pressed, when box-shaped beam shaping, the mould can expand, for the quality of guaranteeing terrace die I4, so evenly open on terrace die I4 has ventilation groove 9, and ventilation groove 9 is seted up on adjacent connection gusset that alleviates between groove 8, and is located the bottom that alleviates groove 8 and frame 1 contact to the circulation of air when guaranteeing the shaping.
The forming method of the elongated box-shaped beam comprises the following steps: firstly, a beam pressure equalizing plate is formed on the beam pressure equalizing plate, when the beam pressure equalizing plate is taken out of a mold, a 2# wedge-shaped block is moved away from the side of a 4# male mold I, and a 3# male mold II is taken out simultaneously when the beam pressure equalizing plate is taken out, so that the beam pressure equalizing plate can be safely and effectively taken out of the mold. And (3) paving a beam to be formed on the male die I and the male die II on a beam forming die, as shown in figure 10, placing a pressure equalizing plate on the surface of the paved beam for controlling the surface quality and thickness of the beam, and carrying out autoclave forming together with the beam forming die. After the box-shaped beam is formed, when the box-shaped beam is taken out of the die, the No. 2 wedge-shaped block is moved away from the No. 4 male die I, and the No. 3 male die II is taken out simultaneously when the box-shaped beam is taken out, so that the box-shaped beam can be safely and effectively taken out of the die.
The working environment of the forming die is vacuum pressure: not less than 0.096MPa, external pressure of 0.8MPa, temperature of 200 ℃, and heat preservation for 3h to realize product molding.
Claims (9)
1. The utility model provides a one side has forming die of combined material elongated box roof beam of negative angle which characterized in that: the forming die comprises a beam forming die and a beam equalizing plate forming die, wherein the die attaching surface of the beam forming die is an inner profile of the box-shaped beam and is used for forming the box-shaped beam, and the die attaching surface of the beam equalizing plate forming die is an outer profile of the box-shaped beam and is used for forming the equalizing plate of the box-shaped beam; the beam forming die comprises a male die I, a male die II and a bottom support, parting surfaces of the male die I and the male die II are perpendicular to the bottom support, the bottom support is used as a bottom surface for forming the box-shaped beam, and the male die I and the male die II are positioned on the bottom support and are manufactured separately from the bottom support.
2. The mold for molding an elongated box beam of composite material having a negative angle on one side thereof as claimed in claim 1, wherein: and a groove is formed in the bottom of the male die II close to one side of the negative angle, a convex positioning block is fixed on the bottom support, and the groove is matched with the convex positioning block and is in contact positioning with the convex positioning block.
3. The mold for molding an elongated box beam of composite material having a negative angle on one side thereof as claimed in claim 2, wherein: and a wedge-shaped block is arranged on one side of the male die II and used for positioning the side face of the male die II.
4. The mold for molding an elongated box beam of composite material having a negative angle on one side thereof as claimed in claim 2, wherein: a plurality of lightening grooves are formed in the male die I, the lightening grooves are evenly distributed along the length direction of the male die I body, and the opening of the lightening grooves faces the bottom support.
5. The mold for molding an elongated box beam of composite material having a negative angle on one side as claimed in claim 4, wherein: and ventilation grooves are formed on the connecting rib plates between the adjacent lightening grooves.
6. The mold for molding an elongated box beam of composite material having a negative angle on one side thereof as claimed in claim 2, wherein: and the male die I is far away from one side of the negative angle, and a part edge line is arranged on the main body of the male die I along the length direction of the male die I and is used as an edge reference line of the box-shaped beam.
7. The mold for molding an elongated box beam of composite material having a negative angle on one side as claimed in claim 6, wherein: a plurality of grooves are formed below the edge line of the part and are uniformly distributed along the length direction of the male die I body.
8. The mold for molding an elongated box beam of composite material having a negative angle on one side thereof as claimed in claim 2, wherein: the bottom support is a frame structure.
9. The mold for molding an elongated box beam of composite material having a negative angle on one side thereof as claimed in claim 1, wherein: the main body structures of the beam forming die and the beam uniform pressure plate forming die are consistent.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202011076081.5A CN112297473A (en) | 2020-10-10 | 2020-10-10 | Forming die for composite material elongated box-shaped beam with negative angle on one side |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202011076081.5A CN112297473A (en) | 2020-10-10 | 2020-10-10 | Forming die for composite material elongated box-shaped beam with negative angle on one side |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN112297473A true CN112297473A (en) | 2021-02-02 |
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Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202011076081.5A Pending CN112297473A (en) | 2020-10-10 | 2020-10-10 | Forming die for composite material elongated box-shaped beam with negative angle on one side |
Country Status (1)
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| CN (1) | CN112297473A (en) |
Citations (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101057073A (en) * | 2004-09-14 | 2007-10-17 | 歌美飒风电有限公司 | Structure beam for wind turbomachine blade and preparation thereof |
| CN103029307A (en) * | 2012-12-12 | 2013-04-10 | 江西洪都航空工业集团有限责任公司 | Manufacture method of box-shaped structural main beam made from composite material |
| CN103264513A (en) * | 2013-05-30 | 2013-08-28 | 中国商用飞机有限责任公司 | Integrated co-curing forming technology method for composite material multi-beam box section |
| CN104175571A (en) * | 2014-09-15 | 2014-12-03 | 沈阳飞机工业（集团）有限公司 | Positioning method for membrane pre-forming of composite material C-shaped beam |
| CN105269721A (en) * | 2015-11-26 | 2016-01-27 | 中国航空工业集团公司基础技术研究院 | Forming mould for composite material part of box type closed-angle structure |
| CN211591370U (en) * | 2019-12-04 | 2020-09-29 | 江西洪都航空工业集团有限责任公司 | Forming die for composite material box-shaped ribs of airplane |
-
2020
- 2020-10-10 CN CN202011076081.5A patent/CN112297473A/en active Pending
Patent Citations (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101057073A (en) * | 2004-09-14 | 2007-10-17 | 歌美飒风电有限公司 | Structure beam for wind turbomachine blade and preparation thereof |
| US20080310964A1 (en) * | 2004-09-14 | 2008-12-18 | Jose Ignacio Llorente Gonzalez | Stuctural Beam for a Wind Generator Blade Production Method Thereof |
| CN103029307A (en) * | 2012-12-12 | 2013-04-10 | 江西洪都航空工业集团有限责任公司 | Manufacture method of box-shaped structural main beam made from composite material |
| CN103264513A (en) * | 2013-05-30 | 2013-08-28 | 中国商用飞机有限责任公司 | Integrated co-curing forming technology method for composite material multi-beam box section |
| CN104175571A (en) * | 2014-09-15 | 2014-12-03 | 沈阳飞机工业（集团）有限公司 | Positioning method for membrane pre-forming of composite material C-shaped beam |
| CN105269721A (en) * | 2015-11-26 | 2016-01-27 | 中国航空工业集团公司基础技术研究院 | Forming mould for composite material part of box type closed-angle structure |
| CN211591370U (en) * | 2019-12-04 | 2020-09-29 | 江西洪都航空工业集团有限责任公司 | Forming die for composite material box-shaped ribs of airplane |
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Application publication date: 20210202 |
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