Abstract:
Aspects of the disclosure are directed to a toolset configured to fabricate a component of an aircraft, the toolset comprising: a mold base configured to seat at least one mandrel, a mold lid configured to be coupled to the mold base, and at least one driver block that is integral with the mold lid and projects from an interior surface of the mold lid.

Description:
BACKGROUND 
       [0001]    Various types of molding techniques may be used to construct components of an aircraft. For example, a resin pressure molding (RPM) technique or a Same Qualified Resin Transfer Molding (SQRTM) technique as developed by Radius Engineering, Inc., combines pre-preg processing and liquid molding to produce components targeted to aerospace applications. Reference may be had to  FIG. 11 , which illustrates a mold  1100  in accordance with the prior art. As part of these techniques, pre-preg plies are arranged within the mold  1100 , the mold  1100  is closed, and then a resin is injected. The resin maintains hydrostatic pressure within the mold  1100 . 
         [0002]    As part of conventional fabrication/molding, a mandrel stack/assembly  1106  including a plurality of mandrels  1106   a  are inserted into a base  1112  of the mold  1100 . Individual tapered tooling pieces  1118   a,    1118   b,    1118   c,  and  1118   d,  typically called “driver blocks”, are the final pieces inserted into the mold assembly. Multiple driver blocks  1118   a - 1118   d  are individually pressed/driven into place, and typically require considerable force to locate properly. These driver blocks  1118   a - 1118   d  create lateral pressures in the mold  1100 . 
         [0003]    The driver blocks  1118   a - 1118   d  may be struck by a hammer or mallet, if necessary, in order to drive the mandrels  1106   a  into predetermined initial positions. Thereafter, a lid (not shown) is placed on top of the mold base  1112  and a press is activated. The press applies pressure to clamp together the lid and the base  1112 , and thereby further drive a driver block  1118   a - 1118   d  into its final position where it pushes laterally against the mandrels  1106   a  to clamp them together. When the fabrication of the component is complete, the press is deactivated, the lid is removed, and then the driver blocks  1118   a - 1118   d  are removed at elevated temperatures, e.g., 350 degrees Fahrenheit (177 degrees Celsius). Removal of the driver blocks  1118   a - 1118   d  at the elevated temperatures represent a cost in terms of the steps a technician/operator must take to remove the driver blocks  1118   a - 1118   d  while still hot, and to avoid burning him/herself. The driver blocks  1118   a - 1118   d  are discrete parts that are inserted and removed separately from the mold  1100 . In  FIG. 11 , the driver blocks  1118   a - 1118   d  are shown at the relative positions they would be located when placed/inserted in the mold  1100 . 
       BRIEF SUMMARY 
       [0004]    The following presents a simplified summary in order to provide a basic understanding of some aspects of the disclosure. The summary is not an extensive overview of the disclosure. It is neither intended to identify key or critical elements of the disclosure nor to delineate the scope of the disclosure. The following summary merely presents some concepts of the disclosure in a simplified form as a prelude to the description below. 
         [0005]    Aspects of the disclosure are directed to a toolset configured to fabricate a component of an aircraft, the toolset comprising: a mold base configured to seat at least one mandrel, a mold lid configured to be coupled to the mold base, and at least one driver block that is integral with the mold lid and projects from an interior surface of the mold lid. In some embodiments, the toolset comprises the at least one mandrel. In some embodiments, the mold base includes a hard stop configured to prevent the at least one mandrel from being inserted into the mold base in an amount greater than a threshold. In some embodiments, the hard stop is configured as an elevated portion of the mold base relative to a floor of the mold base. In some embodiments, the at least one driver block is configured to locate the at least one mandrel in the mold base in terms of at least two reference directions. In some embodiments, the mold base includes a guide configured to couple the mold base and the mold lid. In some embodiments, the at least one driver block includes a plurality of driver blocks. In some embodiments, the toolset is configured to fabricate at least one of a control structure, an airfoil, or a wing of the aircraft. In some embodiments, the toolset is configured to fabricate at least a portion of a stabilizer or stabilator of the aircraft. In some embodiments, the component includes a first skin formed by the mold lid and a second skin formed by the mold base. In some embodiments, the component includes a spar formed by the at least one mandrel. In some embodiments, the at least one driver block includes a double angle and the at least one mandrel includes a matching angle to prevent a mold lock condition. In some embodiments, the at least one driver block is configured to force and hold a composite material to a predetermined dimension during a curing of the component. 
         [0006]    Aspects of the disclosure are directed to a method for fabricating a component using a composite material, the method comprising: laying-up mandrels and skins in a mold base and a mold lid, assembling a mold by assembling the mandrels into the mold base and installing the mold lid onto the mold base, the assembled mold including at least one driver block that is integral with the mold lid and projects from an interior surface of the mold lid, closing the mold and placing the mold into a press, drawing a vacuum and injecting resin, curing the component at a curing temperature, removing the mold from the press, and removing the lid with the at least one integral driver block from the mold base, thereby automatically extracting the at least one driver block from the mold base as the lid is raised. In some embodiments, the lid is removed when the at least one driver block is at a temperature that is close to the curing temperature. In some embodiments, the composite material includes a carbon pre-preg material. In some embodiments, the component includes at least a portion of a stabilizer or stabilator of an aircraft. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0007]    The present disclosure is illustrated by way of example and not limited in the accompanying figures in which like reference numerals indicate similar elements. 
           [0008]      FIG. 1A  illustrates a top view of a mold base in accordance with aspects of this disclosure. 
           [0009]      FIG. 1B  illustrates a perspective view of a portion of the mold base of  FIG. 1A  about the line A-A of  FIG. 1A . 
           [0010]      FIG. 2A  illustrates a top view of a mold lid in accordance with aspects of this disclosure. 
           [0011]      FIG. 2B  illustrates a side view of a portion of the mold lid of  FIG. 2A  about the line A-A of  FIG. 2A . 
           [0012]      FIG. 3A  represents an additional view of the mold base of  FIG. 1A . 
           [0013]      FIG. 3B  represents an additional view of the mold lid of  FIG. 2A . 
           [0014]      FIGS. 4A-4D  illustrate an assembled mold in accordance with aspects of this disclosure. 
           [0015]      FIG. 5  illustrates a method for fabricating a component using the toolset described herein. 
           [0016]      FIG. 6  illustrates a component formed via a toolset in accordance with aspects of this disclosure. 
           [0017]      FIGS. 7A-7B  illustrate a toolset for forming the component of  FIG. 6  in accordance with aspects of this disclosure. 
           [0018]      FIG. 7C  illustrates in detail exemplary guides in the toolset of  FIGS. 7A-7B . 
           [0019]      FIG. 8  illustrates a bottom view/surface of the mold lid of  FIG. 2A  with the guides of  FIG. 7C  at least partially incorporated in the mold lid. 
           [0020]      FIGS. 9A-9B  illustrate angles associated with respective surfaces of a driver block in accordance with aspects of this disclosure. 
           [0021]      FIG. 10  illustrates a provisioning of a composite material in relation to a driver block in accordance with aspects of this disclosure. 
           [0022]      FIG. 11  illustrates a mold in accordance with the prior art. 
       
    
    
     DETAILED DESCRIPTION 
       [0023]    It is noted that various connections are set forth between elements in the following description and in the drawings (the contents of which are included in this disclosure by way of reference). It is noted that these connections are general and, unless specified otherwise, may be direct or indirect and that this specification is not intended to be limiting in this respect. A coupling between two or more entities may refer to a direct connection or an indirect connection. An indirect connection may incorporate one or more intervening entities. 
         [0024]    In accordance with various aspects of the disclosure, apparatuses, systems, and methods are described in connection with a toolset used to produce a component of, e.g., an aircraft. In some embodiments, the toolset may include a mold. The mold may be composed of two or more portions or sections, such as for example a base and a lid. One or more driver blocks may be integral with (e.g., machined as part of or assembled to) the lid. 
         [0025]    Referring now to  FIGS. 1A-1B , a mold base  100  associated with a toolset (e.g., toolset  700  of  FIG. 7A ) is shown. The mold base  100  may include a hard stop  104 . The hard stop  104  may be implemented/configured as an elevated portion of the mold base  100 , relative to a base/floor  110  of the mold base  100 . The hard stop  104  may prevent mandrels (see, e.g., mandrels  302  of  FIG. 3A ) from being inserted/installed too far (e.g., in an amount greater than a threshold) into the mold base  100  in the direction of arrow  116 . More generally, the hard stop  104  may locate the mandrels in a proper/predetermined position. 
         [0026]    Referring to  FIGS. 2A-2B , a mold lid  200  associated with the toolset is shown. The mold lid  200  may include locating/guide features that may provide a technician/operator with direction in terms of coupling/placing the mold lid  200  on top of the mold base  100 . 
         [0027]    The mold lid  200  may include one or more driver blocks/features, such as for example a driver block  206 . In some embodiments, the driver blocks may project from an interior surface  214  of the mold lid  200 . In some embodiments, the driver blocks may be integrally formed with the lid by machining from a single billet of material. The use of a single piece may help avoid introducing crevices where material may inadvertently be located/trapped. Alternatively, the integral driver blocks might be separately formed and mechanically attached, bolted, or welded to the lid. Such separation may facilitate a partial replacement procedure in the event that one or more portions of the mold lid (e.g., a driver block) need to be replaced due to wear, for example. 
         [0028]    The driver blocks  206  may be used for ensuring that the mandrels are properly seated/located within the mold base  100  in one or more reference directions (e.g., reference directions  116   a  and  116   b —see  FIG. 1A ). For example, a driver block  206  is driven in one direction by the press into the mold and the cam angles cause it to push against the mandrels in an orthogonal direction. Pushing the mandrels together helps apply pressure to, e.g., pre-preg located between the mandrels that may form ribs of a component (e.g., a stabilizer or stabilator). A size/dimension of the driver blocks  206  may be selected/predetermined to provide for any of the functionality described above or herein. In reference to  FIG. 4D , lateral pressure is applied without a locking condition or part hang-up occurring as described further below. 
         [0029]    Referring to  FIGS. 3A-3B , the mold base  100  and the mold lid  200  are shown in a disassembled state with respect to on another. In  FIG. 3A  the mold base  100  is shown with mandrels  302  having been inserted/installed. The driver block  206  incorporated in the mold lid  200  may be used to locate/position the mandrels  302  in the mold base  100  within a given tolerance/threshold. 
         [0030]    Referring to  FIGS. 4A-4D , the mold base  100  and the mold lid  200  are shown in an assembled state to form an assembled/complete mold  400 , where the mold lid  200  is placed on top of the mold base  100 . The particular shape/form-factor shown is illustrative; modifications may be made. For example, while the mold  400  is shown as including a sharp corner  408 , the corner  408  may be clipped or rounded to ensure operator/technician safety. An outline of composite material that may be used to fabricate a component is shown in  FIG. 4C  via reference character  412 . 
         [0031]    In some embodiments, one or more portions of the mold  400  may be configured with particular angles or dimensions to prevent mold lock. For example, and as seen in  FIG. 4D , the driver blocks  206  may include a double angle to prevent a lock condition; a matching angle may be included on one or more of the mandrels  302 . A further description of the angles associated with, e.g., the driver blocks  206  is provided below. 
         [0032]    In some embodiments, an integral guide (see  FIG. 9B ) may be included to prevent the mold lid  200  from being driven back/away from the mandrels  302  during a closing of the mold  400 . 
         [0033]    The mold  400  (e.g., the base  100 , the lid  200 , and/or the mandrels  302 ) may be manufactured of one or more materials. For example, the mold  400  may include aluminum, steel, Invar or nickel-alloy, etc. Aluminum may be preferred based on being a relatively light-weight material with a high degree of heat transfer capability. 
         [0034]      FIG. 5  illustrates a method  500  that may be used to fabricate a component using the toolset described herein. 
         [0035]    In block  502 , a lay-up of skins and mandrels may be provided. For example, a skin may be laid-up in a mold base and a skin may be laid-up in a mold lid. One or more mandrels may be laid-up as part of block  502 . 
         [0036]    In block  510 , a mold may be assembled. For example, the mandrels of block  502  may be assembled into the mold base and the mold lid may be installed onto the mold base (and mandrels). 
         [0037]    In block  516 , the mold of block  510  may be closed. As part of block  516 , the mold may be placed in a press (e.g., press  416 —see  FIG. 4A ). The mold may be heated to at least an initial temperature. Such heating may apply via a platen in the press, or the mold itself may include an integrated heating source. 
         [0038]    In block  522 , a vacuum may be drawn. Resin may be injected at an intermediate temperature, where the intermediate temperature is above the initial temperature described above in connection with block  516 . The resin may be injected to create/ensure a constant hydrostatic pressure (typically 75-100 psi) is maintained throughout an injection and cure cycle. During the heat-up phase, as the mold increases in size, there is a tendency for the pressure inside the mold to drop, possibly creating voids in the material. As the resin cures, it increases in volume, and there is a tendency for the pressure in the mold to become higher than optimum, if some of the resin cannot be pushed back out of the mold. The injection resin maintains pressure at the desired level throughout. 
         [0039]    In block  528 , the, temperature may continue to increase (relative to block  522 ) until a threshold temperature is reached, referred to herein as a curing temperature. At this temperature the component may be formed via curing. 
         [0040]    In block  534 , the mold may be removed from the press and the mold lid may be removed. The lid may be removed when the driver blocks are still at an elevated temperature, such as for example close to the curing temperature of block  528 . Such removal may be provided to avoid the mold material (e.g., aluminum) from shrinking to the point where removal of the component may become difficult. 
         [0041]    In block  540 , the component that is formed may be cooled and/or de-molded. 
         [0042]    The method  500  is illustrative. In some embodiments, one or more of the blocks or operations (or portions thereof) may be optional. The blocks/operations may execute in an order or sequence that is different from what is shown. In some embodiments, additional blocks/operations not shown may be included. 
         [0043]    In some embodiments, a component that is fabricated/formed via the toolset described herein may include a control structure, an airfoil, or a wing of an aircraft. In some embodiments, a component that is fabricated/formed via the toolset described herein may include at least a portion of a stabilizer or stabilator of an aircraft. 
         [0044]    An example of a component  600  that may be fabricated/formed via the toolset described herein is shown in  FIG. 6 . In particular, the component  600  may include a first or upper skin  604  formed by the lid  200 , a second or lower skin  610  formed by the base  100 , and one or more spars  616  that may be formed by the mandrels  302 . 
         [0045]      FIG. 7A  illustrates, in an exploded/disassembled state, a toolset  700  that may be used to fabricate/form the component  600 . In particular, the toolset  700  is shown as including the mold base  100 , the mold lid  200 , the mandrels  302 , and a caul plate  708 . As one skilled in the art would appreciate, the caul plate  708  may be used to protect one or more o-rings from incurring wear. 
         [0046]      FIG. 7B  illustrates the toolset  700  in an assembled state. As shown in  FIGS. 7B-7C  the toolset  700  may include one or more guides or guiding devices/features  714 . The guides  714  may be used to facilitate the assembly of the toolset  700  or the coupling of the mold base  100  and the mold lid  200 .  FIG. 8  provides another view of the mold lid  200  with the guides  714  at least partially incorporated therein. 
         [0047]    There are a number of form factors that may be used, for the guides. For example,  FIGS. 7C and 8  illustratively depict the guides  714  as being formed via tabs/flanges in the mold lid  200  and pockets/recesses in the mold base  100 . In some embodiments, the guides may include one or more tracks that may couple to/mate with a roller/wheel for purposes of forming an assembled mold as described above. Alternatively, or additionally, the guides may include tooling pins, tapered pieces, etc. 
         [0048]    In some embodiments, the guides may be configured to selectively engage or mate with one another in advance of the driver blocks  206  entering, or fully protruding into, a cavity formed in the assembled mold base  100  and mold lid  200 . 
         [0049]    As shown in  FIG. 9A , a driver block  206  may include a first surface  902  that is oriented at an angle  908  relative to, e.g., a normal of the mold lid  200 . The angle  908  may be at least seven degrees in some embodiments. 
         [0050]    As shown in  FIG. 9B , the driver block  206  may include a second surface  912  that is oriented at an angle  918  relative to the normal of the mold lid  200 . The angle  918  may be at least seven degrees in some embodiments. In some embodiments, a combination or summation of the angles  908  and  918  may be at least fourteen degrees. Other values for the angle  908 , the angle  918 , or the combination of the angles  908  and  918  may be used. For example, in some embodiments the angle  908  and/or the angle  918  may have a value within a range of: (1) five to ten degrees, (2) four to fifteen degrees, or (3) three to twenty degrees. 
         [0051]      FIG. 10  illustrates composite material  1010  in relation to a driver block  206 . The driver block  206  forces and holds the composite material  1010  to a predetermined dimension (e.g., thickness) during curing. For example, the driver block  206  may force a compression of the composite material  1010  before and during a curing cycle. A press (e.g., press  416 ) may assist in holding and maintaining that compression. 
         [0052]    Technical effects and benefits of the disclosure include an integration of driver blocks with a mold lid. Such integration may reduce procedural steps that need to be taken by an operator/technician as the operator might not need to engage in a separate step of installing or removing the driver blocks. Still further, the integration of the driver blocks with the lid may enhance safety as the operator might not need to separately handle the driver blocks; the driver blocks may be removed with the lid following the formation/fabrication of a component. 
         [0053]    Aspects of the disclosure have been described in terms of illustrative embodiments thereof. Numerous other embodiments, modifications, and variations within the scope and spirit of the appended claims will occur to persons of ordinary skill in the art from a review of this disclosure. For example, one of ordinary skill in the art will appreciate that the steps described in conjunction with the illustrative figures may be performed in other than the recited order, and that one or more steps illustrated may be optional in accordance with aspects of the disclosure. One or more features described in connection with a first embodiment may be combined with one or more features of one or more additional embodiments.