Patent ID: 7311179

Claim:
An elevator dampening device comprising: a hydraulic motor having an axle; a hydraulic fluid reservoir in fluid communication with the hydraulic motor; a relief valve in fluid communication with the motor and the reservoir; a check valve in fluid communication with the motor and the reservoir; hydraulic fluid in the hydraulic fluid reservoir and the motor; a cog attached to the axle of the hydraulic motor and the cog having an alternating series of radially projecting teeth and grooves; a pair of guide rollers being axially spaced and coaxially parallel; a non-rigid track having a series of projecting teeth fitting into the series of grooves on the cog; wherein said cog is offset perpendicularly from said axis of said guide rollers; wherein said guide rollers cause the track to firmly engage the cog; wherein the cog substantially resists downward motion along the track; and wherein said non-rigid track comprises at least one roller chain attached to a structure above an elevator car containing a load, said at least one roller chain allowing said elevator car to move up and down along said at least one roller chain.