Abstract:
A transportation tool for transporting, for example, a single composite aircraft fuselage section, including a first spindle weldment mounted on a first tower, and a second spindle weldment mounted on a second tower and configured to couple the single composite aircraft fuselage section to the towers. A first gimbal assembly configured to allow the first spindle weldment to move independent of the first tower, and a second gimbal assembly configured to allow the second spindle weldment to move independent of the second tower.

Description:
TECHNICAL FIELD 
     The present embodiments relate to a tool used for handling multiple-length composite fuselage sections with integrated related tooling and used to assist with trim and non-destructive inspection (NDI) operations of multiple-length composite fuselage sections. 
     BACKGROUND 
     Aircraft manufacturing technology has advanced to the state where the creation of a very large one-piece aircraft composite fuselage section creating load requirements of near 50,000 lbs (22,680 kgs) is possible. 
     These unique airplane fuselage sections have driven a need for proper handling equipment. For example, in test programs for large aircraft composite fuselage sections, a need has arisen for a tool capable of supporting, positioning and transporting large composite fuselage sections of varying lengths, while the sections are integrated with layup tools and internal support tooling. The sections must be supported and positioned while being transported throughout a factory and while being moved in and out of an autoclave. Heretofore, such large transport tools were not necessary since the manufacture of large composite fuselage sections was not done. 
     SUMMARY 
     The present disclosure provides a tool capable of supporting, positioning and transporting large composite fuselage sections of varying lengths. Moreover, the tool of the present disclosure may be capable of supporting, positioning and transporting the sections with integrated layup tools and internal support tooling throughout a factory and while being moved in and out of an autoclave. 
     In an aspect of the disclosure, a transportation tool is provided that includes a first tower, and a second tower. A first side rail and a second side rail secure the first tower to the second tower to support a payload. The first and second side rails define vacuum chamber accumulators. 
     In another aspect of the disclosure, a transportation tool is provided for transporting a single composite aircraft fuselage section. The tool includes a first spindle weldment mounted on a first tower, and a second spindle weldment mounted on a second tower. The spindle weldments are configured to couple the single composite aircraft fuselage section to the first and second towers. Also included is a first gimbal assembly configured to allow the first spindle weldment to move independent of the first tower, and a second gimbal assembly configured to allow the second spindle weldment to move independent of the second tower. The tool further includes a first side rail and a second side rail for securing the first tower to the second tower. The first and second side rails define vacuum chamber accumulators. 
     In yet another aspect of the disclosure, a method is provided for manufacture of a one-piece composite aircraft fuselage. The method comprises loading a composite fuselage into a support structure, performing vacuum bagging operations on the composite fuselage, and maintaining vacuum integrity of the bagged composite fuselage for processing in an autoclave using vacuum accumulators integrated into the support structure. 
     Additional objects and features of the disclosure will be set forth in part in the detailed description which follows. It is to be understood that both the foregoing general description and the following detailed description are merely example embodiments of the disclosure, and are intended to provide an overview or framework for understanding the nature and character of the embodiments of the disclosure as they are claimed. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       The accompanying drawings are included to provide further understanding of the disclosure, illustrate various embodiments, and together with the description serve to explain the principles and operation of the embodiments. In the drawings, the same components have the same reference numerals. The drawings illustrate the present embodiments, but do not to limit the claims. The drawings include the following Figures: 
         FIG. 1  is a support, position and transport tool for a large payload in accordance with one of the present embodiments; 
         FIG. 2  is an exploded view of the tool of  FIG. 1  in accordance with one of the present embodiments; 
         FIG. 3  is an exploded view of a component of the tool of  FIG. 1  in accordance with one of the present embodiments; 
         FIGS. 4A and 4B  are perspective views of the first and second towers in accordance with one of the present embodiments; 
         FIG. 5  is a detailed perspective view of a tower of the transport tool of  FIG. 1  in accordance with one of the present embodiments; and 
         FIG. 6  is an illustration of a removable disk brake in use with a drive system in accordance with one of the present embodiments. 
     
    
    
     DETAILED DESCRIPTION 
       FIG. 1  is an illustration of a multi-use transport tool  100  or cart created to support, position and transport a payload  102 , with a capacity of up to approximately 50,000 lbs (22,680 kgs). In one embodiment, payload  102  includes a composite fuselage section of an aircraft and may further include integrated layup and support tooling. As an example of the capacity of tool  100 , payload  102  may be a payload up to about 42 ft (12.8 m) long with a diameter of up to about 20 ft (6.1 m). 
     Payload  102  may be manufactured using well-known composite manufacturing techniques, which may involve using tape layup processes that require the use of an autoclave to cure the composite material. Accordingly, tool  100  is capable of enduring adverse environments such as those generated by an autoclave, for example, elevated temperatures of about 450° F. (232° C.) and elevated pressures of about 90 psi (621 kPa). Tool  100  may be used to support and transport payload  102  from an area including a tape layup machine to an area housing the autoclave. Tool  100  may be required to support payload  102  in the environment created by the autoclave for the duration of a cure cycle. Tool  100  may then be used to transport payload  102  to non-destructive inspection (NDI) and trim area. Those of ordinary skill in the art will appreciate that the present multi-use transport tool  100  is not limited to applications involving composite payloads. 
     After tool  100  has been used to support payload  102  throughout the composite layup and curing, process, tool  100  may then be used in conjunction with secondary support tooling (not shown) to transport payload  102  to a location that may be, for example, miles (kilometers) away. As described below, tool  100  includes features to reduce deflection in payload  102  caused by dynamic load effects experienced during the entire transport sequence. 
       FIG. 2  is an exploded view of tool  100  in accordance with one of the present embodiments. In the illustrated embodiment, tool  100  includes first tower  202 , second tower  204 , first side rail  206 , second side rail  208 , free end spindle weldment  210 , geared end spindle weldment  212 , free end gimbal assembly  214 , and geared end gimbal assembly  216 . Eight swivel casters  218 , twelve autoclave casters  220 , a pneumatic powered drive system  222  and a pneumatic disk brake system  224  with pneumatic controls facilitate the transportation function of tool  100 . Those of ordinary skill in the art will appreciate that different numbers of swivel casters  218  and autoclave casters  220  may be provided. 
     The supported payload  102  indexes to spindle weldments  210 ,  212  with a receptacle  302  ( FIG. 3 ) that captures a spherical hub (not shown). As shown in  FIG. 1 , generally, the hub along with mandrel  104  is an integrated part of payload  102  and thus is common among different types of payloads. After indexing payload  102 , mandrel  104 , supporting payload  102 , and tool  100  may then be bolted at spindle weldments  210 ,  212 , for example, along the bolt pattern  304  shown in  FIG. 3 . 
     As shown in  FIGS. 2 ,  4 A,  4 B and  5 , spindle weldments  210 ,  212  each rest on gimbal assemblies  214 ,  216 , respectively. Each gimbal assembly  214 ,  216  is supported by structural first tower  202  and second tower  204 , respectively. Towers  202 ,  204  can be made of any suitable material, such as steel for example. 
     Tool  100  may experience various transportation routes. For example, the uncured payload  102  may be transported from a layup area to a cure area. The post cure payload  102  may be transported from the cure area to a trim, test and assembly area. The trimmed payload  102  may be transported from the trim/test/assembly area across roadways (which can include railroad tracks) to various other locations, such as a paint hangar. All of these moves may cause payload  102  to experience dynamic effects created by rough and uneven surfaces. As a result, the relative position of first tower  202  and second tower  204  may see movement, deflection, racking and vibration with respect to each other and/or with respect to the payload  102 . Undesirable loads, deflections, racking or vibrations can be transferred into and to have undesirable effects on the production payload  102 . For example, wrinkles may develop in the pre-cured payload  102  when moving it from the layup area to the cure area. 
     In accordance with one of the present embodiments, gimbal assemblies  214 ,  216  are incorporated into tool  100  to reduce the effects of the undesirable loads. Gimbal assemblies  214 ,  216  reduce induced deflections of the pre-cured and post-cured payload  102  as well as provide bearings for support and rotation. 
     Gimbal assemblies  214 ,  216  allow payload  102  to be supported independent of the deflections experienced by tool  100 . With reference to  FIG. 5 , gimbal assemblies  214 ,  216  allow payload  102  and spindle weldments  210 ,  212  to rotate about longitudinal axis  502 X, lateral horizontal axis  502 Y, and vertical axis  502 Z using, for example, a set of roller bearings. 
     As best illustrated in  FIG. 5  with regard to gimbal assembly  214 , each gimbal assembly  214 ,  216  may be vertically repositioned as indicated by arrow  506  to an elevated height H. Height H may range from 0 ft (0 m) to about 3 ft. (0.9 m). Before moving gimbal assemblies  214 ,  216  along arrow  506 , payload  102  may be removed. With the payload  102  removed, gimbal assemblies  214 ,  216  are lifted to expose a portion of column  508 . A pin  510  is then positioned through column  508  to bear on platform  511  and hold column  508  at the elevated position H. The ability to raise and lower gimbal assemblies  214 ,  216  assists for example NDI, bagging and trimming operations. 
     As shown in  FIGS. 3 ,  4 A and  6 , spindle weldment  212  on first tower  202  at the drive end of tool  100  is coupled to drive system  222  that controls longitudinal rotation of payload  102 . In one embodiment, drive system  222  is pneumatically powered. For example, drive system  222  may operate with shop supplied air routed through a control box (not shown). In one embodiment, as shown in  FIG. 3 , load may be transmitted by an air motor  306  and a series of chain driven gears  308 . In one embodiment, through a particular arrangement of gears, motor  306  can generate an output beyond 8,300 ft-lbs (11,200 Nm) of torque. 
     In one embodiment, drive system  222  may rotate payload  102  both in the clockwise and counterclockwise directions. When motor  306  is powered on, pneumatic disk brake  602  ( FIG. 6 ) may be disengaged. When motor  306  is powered off, pneumatic disk brake  602 . may be engaged. Once payload  102  comes to rest, pneumatic disk brake  602  resists undesired rotation of payload  102 . In one embodiment, disk brake  602  may resist up to 16,600 ft-lbs (22,510 Nm) of torque, including a safety factor. In one embodiment, air motor  306  and disk brake  602  are removable from toot  100  so that air motor  306  and disk brake  602  are not exposed to the autoclave environment. Once the autoclave operations are complete, motor  306  and brake  602  may be reinstalled. 
     In one operational example, the power and braking systems may be expected to turn and stop an unbalanced payload  102  at up to 8,333 ft-lbs (11,300 Nm) of torque. In this example, payload  102  is a composite fuselage section. Due to tolerances in layup tool manufacturing and layup variability, a 50,000 lb (22,680 kg) load could vary from the theoretical axis of rotation by up to 2 in (5 cm). Also, different geometries of fuselage sections can add to the generation of imbalanced loads. 
     It is undesirable for an imbalanced payload  102  to spool freely. Spooling may be controlled by applying back pressure to the air motor.  306 . Since the example system is pneumatically powered, it may function such that when the air is on, motor  306  turns and brake  602  is disengaged. In one embodiment, to power air motor  306  an operator must physically hold the control knob to an on position. When the air is off, motor  306  ceases operation and a spring loaded brake  602  is applied. Brake  602  is disengaged with air pressure and engaged by releasing the air pressure in order to activate the spring mechanism. 
     Alternatively, a set of lock pins  400  as shown in  FIGS. 4A and 4B , one per tower  202 ,  204 , may be inserted through bearing assemblies on gimbal assemblies  214 ,  216  to serve as a backup to brake  602  for prevention of rotation during stationary operations. In one embodiment, the lock pin  400  and housing  402  are engineered to resist over 41,600 ft-lbs (56,400 Nm) of torque including a safety factor. Additionally, the lock pins may serve the same function for ground transportation operations. The pins are installed and removed manually. 
     As shown in  FIGS. 4A and 4B , spindle weldments  210 ,  212  on the first and second towers  204  rest on bearings  404 , which allow for rotation of spindle weldments  210 ,  212  about longitudinal. axis A L . Spindle weldments  210 ,  212  also allow for translation along longitudinal axis A L , which may be caused by thermal expansion during the payload  102  build/cure/transport cycle. 
     As shown in  FIGS. 2 ,  4 A, and  4 B, first tower  202  and second tower  204  are joined together by a first hollow side rail  206 , a second hollow side rail  208  and fasteners  410 . In certain embodiments, the side rails  206 ,  208  may not be hollow. However, in embodiments in which the side rails  206 ,  208  are hollow they may serve as vacuum accumulators to maintain vacuum pressure to a bagged payload  102 , such as a bagged pre-cured composite fuselage section. Hollow side rails  206 ,  208  are equipped with valve fittings  226  ( FIG. 4A ) to connect vacuum hoses (not shown). 
     Typically, vacuum accumulators are a separate independent system attached to transport tools. In accordance with the present embodiments, integrated parts of tool  100 , namely hollow side rails  206 ,  208 , may be used as vacuum accumulators. This adaptation reduces tooling costs. 
     The hollow side rails  206 ,  208  comprise an integrated vacuum system, which may be used to hold vacuum on a bagged payload  102  while the payload  102  is being transported, for example, from a layup area to a curing area. The integrated vacuum system may also be used after cure to transport the payload  102  to the NDI and trim area. 
     In one embodiment, once air is pumped out of the hollow side rails  206 ,  208 , the hoses are disconnected from the valves  226  leaving hollow side rails  206 ,  208  charged with less than atmospheric pressure. When needed in the transport process, hoses can be re-connected from hollow side rails  206 ,  208  to the bagged payload  102 . In this embodiment, the bagged payload  102  has previously had air evacuated from it and been sealed. When the bagged payload  102  is connected via the hoses to the hollow side rails  206 ,  208 , the valves  226  are opened so that the vacuum pressure in the hollow side rails  206 ,  208  is transferred to the bagged payload  102 . In this manner, vacuum pressure can be maintained on the bagged payload  102  such that any leaking in the bag system is overcome. 
     As best shown in  FIGS. 4A and 4B , for ground transportation, each tower  202 ,  204  has four swivel casters  218 . In certain embodiments, the swivel casters  218  may be spring loaded. To shuttle the payload  102  in and out of the autoclave, the swivel casters  218  are removed from each tower  202 ,  204 . Towers  202 ,  204  are equipped with jack support points  406  ( FIG. 4B ) to raise and lower the towers  202 ,  204 . Using jack supports (not shown), tool  100  may be lowered on to a different set of casters  220 , referred to as autoclave casters  220 . Each tower  202 ,  204  may have at least six autoclave casters  220 . Each autoclave caster  220  may have a raised ridge  408  circumscribing the caster  220  that coordinates to recessed floor mounted steel tracks (not shown). 
     Again referring to  FIGS. 4A and 4B , each tower  202 ,  204  may be equipped with a tow bar  412 . Tow bar  412  may be used to connect the assembled tool  100  to a towing device (not shown) such as a tug or a fork truck. One tow bar  412  may be used for longitudinal towing and another (not shown) may be attached to the side(s) of either or both towers  202 ,  204  for lateral positioning. 
     The scope of the present disclosure should not be limited to the particular embodiments illustrated and described herein, as they are merely examples, but rather, should be fully commensurate with that of the claims appended hereafter and their functional equivalents.