An apparatus includes a drum to draw in or let out a line and a motor and transmission coupled to the drum to apply a torque thereto. An encoder is provided to measure an angular position of the drum. A counter is provided to record a number of rotations of the drum. A locking mechanism automatically prevents rotation of the drum when the drum stops. Using this information, a processor may calculate an amount of line let out from the drum based on the number of rotations of the drum, the angular position of the drum, and a radius of the drum. In certain embodiments, the angular position and/or number of rotations is stored in non-volatile memory so that is can be recovered in the event of a power outage or other significant event.
Accurate Position Tracking for Motorized Lifting Device
2015-10-08
Patent
Electronic Resource
English
IPC: | B66D Haspeln , CAPSTANS |
Motorized Lifting Device with Accurate Weight Measuring Capability
European Patent Office | 2015
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