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US 5,439,200 AGranted
Air lifting and balancing unit
AssigneeColumbus McKinnon Corporation
InventorsRobert O. Braesch, Peter L. Hong, Thomas A. Mefferd, Michael D. Olson
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AssigneeColumbus McKinnon Corporation
InventorsRobert O. Braesch, Peter L. Hong, Thomas A. Mefferd, Michael D. Olson
Estimating the term…
An air lifting and balancing unit including a cylinder, a piston in the cylinder, a ball screw affixed to the piston, a ball nut mounted for rotation on the ball screw, a drum mounted on the ball nut, a chain driven by the drum, and centrifugally actuated brakes mounted on the drum for stopping rotation of the drum when the drum exceeds a predetermined acceleration either due to a loss of load or to a loss of air pressure applied to the piston, and a pneumatic circuit in communication with the cylinder for providing air pressure thereto which applies a force on the piston which is at a substantially constant incremental value in opposition to the force exerted by the load applied to the piston through the chain and the drum and the ball screw regardless of variations in said air pressure to thereby cause the speed of the chain to remain substantially constant.
An air lifting and balancing unit comprising a cylinder, a piston in said cylinder, a ball screw affixed to said piston, a ball nut, means mounting said ball nut for rotation on said ball screw, drum means mounted on said ball nut for moving an elongated member which carries a load, brake means mounted relative to said drum, and means for causing said brake means to stop rotation of said drum when said drum exceeds a predetermined acceleration.
An air lifting and balancing unit comprising a cylinder, a piston in said cylinder, a ball screw affixed to said piston, a ball nut, means mounting said ball nut for rotation on said ball screw, drum means mounted on said ball nut for rotation with said ball nut, an elongated member mounted on said drum means for carrying a load, brake means mounted relative to said drum means, means for causing said brake means to stop rotation of said drum means when said drum means exceeds a predetermined acceleration, and pneumatic circuit means in communication with said cylinder for providing air pressure thereto to produce a force on said piston which is at a substantially constant incremental value in opposition to the force transmitted by said load to said piston to thereby cause the speed of said piston to remain substantially constant regardless of variations in said air pressure and thereby cause the speed of said elongated member to remain substantially constant.
Dependencies are inferred from the claim text.