摘要 |
A pump drive assembly is disclosed. The assembly includes a driver, a pump drive member driven by the driver, and a decoupler that decouples the drive member from the driver when a force acting upon the drive member exceeds a threshold force. The pump drive member can be a piston rod, and the decoupler can be a magnet attached to the piston rod and coupled to a magnetically attracted plate driven by the driver. When a force resisting movement of the piston rod exceeds the magnetic force coupling the magnet to the plate, the magnet decouples from the plate, and the pumping operation ceases.
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