Help with a backup manual drive mechanism for a chain drive system
Help with a backup manual drive mechanism for a chain drive system
(OP)
Good afternoon, and thank in advance for any help or suggestions. Apologies if this is not posted in the correct area!
I have a chain driven mechanism that raises and lowers a sensor, and I have previously designed a manual drive back up for the emergency case where we lose power to the drive motor (or the motor fails). This is to prevent damage to the sensor. Everything worked well until the client changed the sensor to one much heavier than the previous. The motor that we were previously using now back drives (lowers the sensor) under just the hanging load of the new sensor. We then upgraded the motor to a 90 degree drive motor which cannot be back driven (at least not at this weight). Unfortunately the new motor cannot be manual driven either!
So I want to introduce a method of disengaging the motor from the chain drive system.
I have attached a rough sketch of my concept in doing this, but I feel as though I am missing a simpler solution to the problem. I'm the only engineer on staff here, so I have no one to bounce ideas off of, so looking for some back and forth discussion. The chain drive sprockets (shown in red) are the only thing that is fixed at this time. They cannot be moved from their current location, all other components are up for debate.

I have a chain driven mechanism that raises and lowers a sensor, and I have previously designed a manual drive back up for the emergency case where we lose power to the drive motor (or the motor fails). This is to prevent damage to the sensor. Everything worked well until the client changed the sensor to one much heavier than the previous. The motor that we were previously using now back drives (lowers the sensor) under just the hanging load of the new sensor. We then upgraded the motor to a 90 degree drive motor which cannot be back driven (at least not at this weight). Unfortunately the new motor cannot be manual driven either!
So I want to introduce a method of disengaging the motor from the chain drive system.
I have attached a rough sketch of my concept in doing this, but I feel as though I am missing a simpler solution to the problem. I'm the only engineer on staff here, so I have no one to bounce ideas off of, so looking for some back and forth discussion. The chain drive sprockets (shown in red) are the only thing that is fixed at this time. They cannot be moved from their current location, all other components are up for debate.






RE: Help with a backup manual drive mechanism for a chain drive system
RE: Help with a backup manual drive mechanism for a chain drive system
Dog clutch? If you don't need the gearset, a dog clutch (very common in marine drives) would allow direct drive.
je suis charlie
RE: Help with a backup manual drive mechanism for a chain drive system
RE: Help with a backup manual drive mechanism for a chain drive system
COTS solutions are always best, would love to find something to just drop in.
So the "safe" position for the sensor is in the up or fully retracted position. I have a set of positive locking pins for when the sensor reaches this position, which engage mechanically. So in the instance where we lose power or the motor, we manually drive the sensor back up until the pins engage. Then we have no issue with back driving.
RE: Help with a backup manual drive mechanism for a chain drive system
RE: Help with a backup manual drive mechanism for a chain drive system
RE: Help with a backup manual drive mechanism for a chain drive system