2 Speed AMM

Antonov 2-Speed Mechanical Module, (AMM)

The Antonov 2-Speed Mechanical Module, AMM, is based on one of Antonov’s original patents. At the heart of the device is a self controlling, fully automatic mechanical shift system. The AMM utilises internal mechanical forces created by torque and speed to effect a smooth, clean shift between two gear ratios.

As part of the requirements for reduced CO2 emissions and fuel consumption, vehicle OEMs are constantly reducing the idle speed of their engines. At these low engine speeds, engine accessories such as alternators and superchargers do not perform optimally or efficiently. The Antonov AMM provides an ideal solution to this problem by overspeeding engine accessories at low engine rpms and then reverting back to direct drive at higher engine rpms. The AMM can be incorporated into the FEAD system in several ways. It can be integrated with a single accessory, be a standalone unit within the belt run, or even incorporated into the crank nose pulley so that all engine accessories can be driven at 2-speeds.

As well as optimising the performance and efficiency of engine accessories, the AMM could be used as an automatic transmission for recreational vehicles such as ATVs and boats, and it lends itself particularly well to military applications where not having an electronic control system would be an advantage.

AMM Principle of Operation

The AMM principle of operation is to control a gear shift from a speed increasing ratio of between 1:1.2 and 1:1.9 and direct drive, 1:1, through the use of mechanical forces generated within the unit by speed and torque. Axial force generated by centrifugal weights acts against spring preload and axial force generated by torque on helical gears. As the input speed to the AMM increases, at a particular input speed, which can be tuned for each individual application, the axial force generated by the centrifugal weights overcomes the other two forces and the AMM shifts from the overspeeding ratio to direct drive. Conversely, as the input speed decreases, the axial force generated by the centrifugal weights decreases to a point where it can no longer overcome the spring and gear axial forces, and the AMM shifts to the overspeeding ratio. Because of hysteresis in the system, there is a 200-300rpm difference between the upshift and the downshift. This means that the AMM does not hunt between the two ratios and is always positively in one ratio or the other.