DOC AIRBUS | AMM A320FACCESSORY DRIVE GEARBOX - DESCRIPTION AND OPERATION
** ON A/C NOT FOR ALL
** ON A/C NOT FOR ALL
1. General
The cast-aluminum accessory-drive gearbox (referred to as the gearbox) has the drive pads for the Auxiliary Power Unit (APU) generator and accessories which include:
** ON A/C NOT FOR ALL The cast-aluminum accessory-drive gearbox (referred to as the gearbox) has the drive pads for the Auxiliary Power Unit (APU) generator and accessories which include:
- the starter motor assembly,
- the oil pump module,
- the fuel control unit (FCU),
- the cooling-air fan assembly.
** ON A/C NOT FOR ALL
Accessory Drive Gearbox3. Description
The gearbox is designed as a module. You can remove it from the APU leaving all the gears, bearings and seals in position. The gearbox is of a low weight design with improved gear lubrication and is fitted with a heater to aid start reliability.
A flanged joint attaches the gearbox to the load compressor. The APU gives a direct drive to the gearbox. The APU forward side mounts are part of the gearbox structure, which is also an oil reservoir (for the wet-sump lubrication system) (Ref. AMM D/O 49-90-00-00). The capacity of the oil reservoir is 6.26 l (1.6537 USgal). The gravity fill port is part of the gearbox housing. A direct-reading sight glass, installed adjacent to the gravity fill port, gives a visible oil-level indication. An oil level switch, installed in the sump, gives minimum oil-level indication signals to the Electronic Control Box (ECB) 59KD (Ref.
The gearbox is of the nonpressurised type. All the accessories mounted on the APU gearbox are approved by the APU manufacturer's type certification.
This meets the requirements of JAR 25A 1011, 1163 (a) and 25B 1163.
Accessory Drive Gearbox
** ON A/C NOT FOR ALL The gearbox is designed as a module. You can remove it from the APU leaving all the gears, bearings and seals in position. The gearbox is of a low weight design with improved gear lubrication and is fitted with a heater to aid start reliability.
A flanged joint attaches the gearbox to the load compressor. The APU gives a direct drive to the gearbox. The APU forward side mounts are part of the gearbox structure, which is also an oil reservoir (for the wet-sump lubrication system) (Ref. AMM D/O 49-90-00-00). The capacity of the oil reservoir is 6.26 l (1.6537 USgal). The gravity fill port is part of the gearbox housing. A direct-reading sight glass, installed adjacent to the gravity fill port, gives a visible oil-level indication. An oil level switch, installed in the sump, gives minimum oil-level indication signals to the Electronic Control Box (ECB) 59KD (Ref.
The gearbox is of the nonpressurised type. All the accessories mounted on the APU gearbox are approved by the APU manufacturer's type certification.
This meets the requirements of JAR 25A 1011, 1163 (a) and 25B 1163.
Accessory Drive Gearbox
4. Operation
The gearbox contains the oil that is used to lubricate the components of the APU. Oil is drawn from the gearbox by a pump and passed to the oil cooler. From the oil cooler, the oil is passed to the various components. The gearbox also contains two filters, each fitted with a pressure relief valve to prevent excessive pressure if the filters become blocked.
The gearbox contains the oil that is used to lubricate the components of the APU. Oil is drawn from the gearbox by a pump and passed to the oil cooler. From the oil cooler, the oil is passed to the various components. The gearbox also contains two filters, each fitted with a pressure relief valve to prevent excessive pressure if the filters become blocked.