DESC: Title of invention
Title of invention: Stay rod mechanism for daily inspection panels in aircraft.
2. Field of invention
The present invention relates to aircraft structural engineering in general, and more particularly to aircraft structural design for inspection panels.
3. Background of invention
Aircraft panels needs to be designed for easy maintainability and reliability. Most of the daily inspection panels are provided with hinged cover with quick release fasteners.
In modern fighter aircraft, some of the service panels which are required to be serviced by Ground Support Equipment (GSE) adaptor after each sortie needs to cater to spring loaded hinge mechanism which “stays” in open position after opening. But due to the frequent operation of the above panel, the effectiveness of the spring hinge reduces leading to sagging of the panel over the time which could cause safety issues and also inhibit Ground Support Equipment (GSE) adaptor mating. These service panels are designed with spring hinge-trigger lock mechanism for quick opening of the panel. Spring hinge failure in the panel may lead to safety and maintainability issues. This leads to additional cost for the replacement of spring hinge and it increases aircraft down time.
In the prior art of aircraft panel system, spring hinge mechanism was used. The drawbacks of the prior art include:
a. it has limited life cycle;
b. it does not ensure the integrity of the panel for the full cycle of the aircraft;
c. sagging of the panel due to the weakening of the spring hinge which leads to limited access to LRU’s (Line Replaceable Units), thereby hindering access and maintenance;
d. it may not be visible during routine visual inspections. Checking of hinge and trigger locks each time would increase inspection downtimes before each sortie. Degradation of the spring effectiveness is difficult to quantify in inspections and it is subjective, leading to vulnerability; and
e. its overall reliability is less.
4. Summary of the present invention
The primary objective of the present invention is to provide an improved and reliable panel opening stay system to enable ease of maintenance. In small panels, due to space required for adaptor interface, it is difficult to integrate elaborate stay mechanism due to space constraints. The present invention uses stay rod mechanism, which is hinged at bracket and positioned at the frame location in the open position of the panel. The present invention ensures that the panel is opened at the desired angle of opening (above 90deg), consistently, and there is no compromise on safety and accessibility aspects. This mechanism does not occupy any space in the system maintenance area. The present invention enables clear and consistent access, thereby improving overall maintainability and reliability of the panels. Safety aspects in flight operation is completely mitigated in this scheme.
5. Brief description of drawings
Fig-1: illustrates the preferred embodiment of the present invention - a stay rod mechanism (100) for Daily inspection panels in aircrafts with stay rod (101), link (102) etc. The stay rod mechanism (100) is placed at the identified location.
6. Detailed description of invention
Refer FIG-1. This panel (108) is designed with two trigger locks (107) and piano hinge (106) along with stay rod mechanism (100). The aircraft technician needs to press the trigger locks (107) for unlocking the panel (108). The stay rod mechanism (100) consists of stay rod (101), link (102), bolt(103) and threaded bracket (104). The threaded bracket (104) and bolt(103) secures the link(102) and stay rod(101) in the panel(108). The stay rod(101) is secured with a spring clip (105) in the panel (108) at closed position. Once the trigger lock (107) is pressed, the panel (108) can be opened through hinged axis which is attaching both the fixed and removable panel (108).
In next step, remove the stay rod (101) from the spring clip (105) (11 0’clock position) and rotate it clockwise about the link (102) and threaded bracket (104) center axis and lock it in the spring clip (105) (3 0’clock position), positioned inside bottom of the panel (108). Now the stay rod (101) is positioned perpendicular to the panel (108) and fixed structure. With the above steps, the service panel (108) is positioned on the fixed structure. In the open position, maintenance of the system LRU’s (Line Replaceable Units) and inspection checks can be carried out.
After inspection, remove the stay rod (101) from the spring clip (105) (3 0’clock position) and rotate it counter clock wise to the locking position (11 0’clock position). Close the panel (108) with the trigger locks (107).
The invention is self-sufficient and can be used for ground maintenance and inspection checks. ,CLAIMS:We Claim:
1. A stay rod mechanism (100) for aircraft daily inspection panels (108), comprising:
- a stay rod (101);
- a link (102) for the rotary motion of the stay rod (101);
- a bolt (103) for locking the stay rod (101) that ensures the safe positioning of link(102) and stay rod(101) permanently onto the panel(108);
- a threaded bracket (104) for stay rod (101) rotary motion; and
- a spring clip (104) that is used to secure the stay rod (101) in the panel (108) at open and closed position.
2. The stay rod mechanism (100) for aircraft daily inspection panels, as claimed in claim 1, wherein, the panel (108) is designed with a plurality of trigger locks (107) and piano hinge (106) along with the stay rod mechanism (100); and the panel (108) is unlocked by pressing the trigger locks (107).
3. The stay rod mechanism (100) for aircraft daily inspection panels, as claimed in claim 1, wherein, combination of the link (102), the bolt (103), and the threaded bracket (104) is ensuring the rotary motion of the stay rod (101) to lock the panel in the desired open position.