Orbiting fairlead block for guiding cables
A pulley block that guides a cable while keeping a minimum bend radius by carrying pulleys in a block that can travel in an arched path relative to its suspension. The block has side plates with one or two bowed carrier members forming an inner circular segment; a traveling carriage or suspending plate with contact elements runs along that arch so the block orbits around a point coincident with the pulley contact circle. Intended users include offshore vessels, winch systems and other heavy-cable handling installations.
(57) What the patent covered
This write-up was generated by AI from the patent's text and may contain mistakes, so check it against the original patent before relying on it.
The main independent claim covered a fairlead block having side elements with at least one pulley on a parallel axis, at least one block carrier bow forming an opening whose inner circular segment defines an arch-shaped traveling path, and a suspension arrangement with a traveling bow contact element forming a carriage that runs along that arch in a plane parallel to the pulley axes; the bow and suspension are arranged so the center of rotation of the inner circular segment coincides with the circumferential contact surface of the pulley nearest the suspension arrangement.
Distinguishing feature: The block carrier bow and travelling carriage produce an orbiting motion where the block’s center of rotation coincides with the pulleys’ circumferential contact surface, constraining cable movement to maintain bend radius.
Novelty 4/5. Most fairleads then pivoted on a single eye or clevis causing lateral and vertical movement; this patent applied an orbiting carriage along an arched bow to keep the rotation center at the pulley contact surface, a new approach to reducing unwanted cable motion.
Manufacturing
Machined or stamped steel side plates and carrier bows; machined pulleys with bearing inserts; manufacture or molding of endless double-curved elastic belt; assembly with pins/hinges and rolling elements onto a suspending plate; bolted assembly and inspection.
Materials: Stamped or machined steel side plates, Forged or machined steel pulleys (sheaves), Elastomeric double-curved endless belt (rubber or polyurethane), Bolts, pins and bearings (steel).
Manufacturability 3/5. Requires multiple machined or stamped metal parts, bearings/rolling elements and an elastic loop; moderate assembly precision for pulley alignment and carriage travel; common metalworking and bearing suppliers suffice.
Market demand
No demand check has been run for this patent. Likely search terms: orbiting fairlead block, cable guide pulley block arched carriage, offshore fairlead orbiting sheave. The links in the sidebar open these searches.
Buyers: Offshore vessel riggers, winch system integrators, heavy lifting contractors.
Before manufacturing
No related continuation or divisional patents in force were found. Design patents, trademarks and unrelated patents may still cover the product.
Patent has lapsed; practical risks include ensuring materials and bearings meet marine corrosion and load requirements and confirming the patent file contains no still-active family members in target markets.
About 1.5% of lapsed patents are later revived by their owners. This page is a research lead, not legal advice. Obtain a freedom-to-operate opinion before manufacturing.