Patent Application
20120006137
The subject matter disclosed herein relates to gearboxes for aircraft. More specifically, the subject disclosure relates to connection of accessories to an aircraft gearbox.
A gearbox transfers power from a main shaft of an aircraft engine to a number of engine and aircraft accessories. A typical suite of accessories may include an electrical generator, hydraulic pump, fuel pump, starter, and oil lubrication and scavenging pump. Typically, these accessories are connected to the gearbox via a coaxial spline between a gearbox gear and the gearbox. This means of connecting accessories to the gearbox forces the accessories to be located at a face of the gearbox where packaging space is limited. Further, because of the direct spline connection, speed of the accessory is determined by the gear speed of the gearbox. Also, locating the accessories on the face of the gearbox increases cantilevering and unequal moments on the gearbox faces requiring increased structural support for the gearbox faces, which increases weight of the gearbox.
According to one aspect of the invention, an accessory gearbox assembly for an aircraft includes one or more intermeshed gears disposed in an accessory gearbox housing and configured to transfer rotational energy from an engine core. An accessory component has an accessory spur gear located at least partially in the accessory gearbox housing. The accessory spur gear is meshed with a gear within the gearbox housing thereby transferring rotational energy from the gearbox to the accessory component.
According to another aspect of the invention, a method for providing rotational energy to an accessory component at an accessory gearbox includes providing rotational energy to one or more intermeshed gears of an accessory gearbox and locating an accessory component at the accessory gearbox. The gearbox component includes a spur gear disposed at least partially in an accessory housing. The spur gear is meshed with a gear of the one or more gears and rotational energy is transferred from the one or more gears to the accessory component via the spur gear.
These and other advantages and features will become more apparent from the following description taken in conjunction with the drawings.
The subject matter, which is regarded as the invention, is particularly pointed out and distinctly claimed in the claims at the conclusion of the specification. The foregoing and other features, and advantages of the invention are apparent from the following detailed description taken in conjunction with the accompanying drawings in which:
The detailed description explains embodiments of the invention, together with advantages and features, by way of example with reference to the drawings.
Shown in
The gearbox 10 is configured to provide rotational energy to one or more accessory components 22 in operable communication with the gearbox 10. The accessory components 22 may be, for example, a fuel pump, lubrication pump, a hydraulic pump, or a cooling fan. In the embodiment of
The accessory component 22 is operably connected to the gearbox 10 via a spur gear 28, which rotates about spur axis 32. One of the gearbox gears 16 is disposed at least partially within an accessory housing 30. The spur gear 28 has a plurality of spur teeth 34 that extend toward a plurality of gear teeth 36 of one of the gears 16 and mesh therewith. The spur gear 28 meshes with the gear 16 such that rotation of the gear 16 drives rotation of the spur gear 28, which in turn drives rotation of an accessory shaft 38 to provide power to the accessory component 22. The spur axis 32 of rotation is substantially parallel to a gear axis 20 of rotation of the gear 16 with which the spur gear 28 is meshed.
Connection of the accessory component 22 to the gearbox 10 via the spur gear 28 allows for simple adjustment of the rotational speed of the spur gear 28 and therefore the rotational energy provided to the accessory component 22 by changing the number of spur teeth 34 in the spur gear 28 or by changing the number of gear teeth 36 in the gear 16 with which the spur gear 28 meshes.
To allow meshing of the spur gear 28 and the gear 16, the gearbox housing 18 includes a gear opening 40 in the longitudinal end 24 and the accessory housing 30 includes a complimentary spur opening 42 to allow one of the gearbox gears 16 and the accessory spur gear 28 to extend therethrough and to mesh. To seal the interface between the gearbox 10 and the accessory component 22 and prevent contaminants from entering the gearbox 10 through the gear opening 40 and from entering the accessory component 22 through the spur opening 42, a seal is provided between the accessory component 22 and the gearbox 10. As shown in
Referring now to
Referring again to
While the invention has been described in detail in connection with only a limited number of embodiments, it should be readily understood that the invention is not limited to such disclosed embodiments. Rather, the invention can be modified to incorporate any number of variations, alterations, substitutions or equivalent arrangements not heretofore described, but which are commensurate with the spirit and scope of the invention. Additionally, while various embodiments of the invention have been described, it is to be understood that aspects of the invention may include only some of the described embodiments. Accordingly, the invention is not to be seen as limited by the foregoing description, but is only limited by the scope of the appended claims.
