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US 5,992,574 AGranted
Method and apparatus to inspect hoisting ropes
AssigneeOtis Elevator Company
InventorsEric G. Olsen, Hugh J. O'Donnell
Life of this patent
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AssigneeOtis Elevator Company
InventorsEric G. Olsen, Hugh J. O'Donnell
Estimating the term…
A hoisting rope includes a plurality of longitudinally spaced, discrete targets retained within the rope. The targets have a characteristic that may be monitored by a device that is responsive to that characteristic. In a particular embodiment, the targets are formed from a magnetically permeable material and the monitoring device responds to changes in the magnetic field as the target passes the monitoring device. In another embodiment, the targets are formed from material that reflects electromagnetic energy. In this embodiment, the monitoring device emits electromagnetic energy and is sensitive to the energy that is reflected back from the target. A method to inspect the hoisting ropes includes the steps of positioning the monitoring device proximate to the hoisting rope, moving the hoisting rope relative to the device, and monitoring the targets to determine the spacing between targets. Changes in spacing are indicative of stretching of the rope, and thereby degradation of the rope.
An elevator hoisting rope including a plurality of discrete targets permanently fixed within the hoisting rope, the targets being spaced along the length of the hoisting rope, the targets having a characteristic that may be monitored by a device responsive to that characteristic, such that changes in spacing between targets may be determined, and wherein such changes in spacing between targets is indicative of degradation in the hoisting rope such that an elongation in the elevator rope may indicate that maintenance or replacement of the rope is necessary.
A method to monitor the degradation of an elevator hoisting rope, the hoisting rope including a plurality of discrete targets permanently fixed within the hoisting rope, the targets being spaced along the length of the hoisting rope, the method including the steps of:
Dependencies are inferred from the claim text.