US 4693068

I'll search for authoritative information on this specific patent number before summarizing.

US Patent 4,693,068 — Summary

Note on sourcing: The authoritative full text supplied in the prompt (from https://patents.google.com/patent/[US4693068](/patent/US4693068)/en) is my primary source. My searches also returned the Justia mirror of the same document (https://patents.justia.com/patent/4693068). I was unable to retrieve anything from the USPTO Patent Public Search/Patent Center or from CAFC 2026 dockets — see "Litigation / Docket Check" below.

Bibliographic data

Abstract (verbatim)

"Device for regulating the tension of a thread through the different transformation operations to which said thread is subjected during its manufacture, said device being of the type forming an assembly comprising cups between which passes the thread, said cups being mounted on a hub and locked in position one against the other by way of a nut, and said hub being mounted on a rotary shaft which is common to all the positions of one face of the machine, device wherein: the cups are mounted in pairs on either side of a cylindrical track which is fast in rotation with said cups, said track having a diameter at least equal to the diameter of the circle of contact between the two cups, and said thread being, while thrown, in contact with the central cylindrical track, and after throwing, pushed back onto the side tracks constituted by each pair of cups in order to be placed in the normal working conditions after throwing; and the nuts holding each pair of cups one against the other enable a variation of their pressure, hence an adjustment of the tension which is communicated to the thread."

Claims structure

The patent has 4 claims; only claim 1 is independent. Claims 2–4 depend from it (2→1, 3→2, 4→1).

Independent Claim 1 — plain-language overview

A rotating "slackener" assembly built on one driven shaft, with two yarn-tensioning stations (rather than the prior single station):

• A rotary shaft carries first and second hubs that rotate with it, their inner ends facing each other (juxtaposed).
• A cylindrical track sits at/adjacent those inner ends, encircling the shaft, and is fixedly secured to at least one of the hubs, so it rotates with them.
• Two nuts — one threaded on the outer end of each hub — can be moved axially to change clamping pressure.
• Two pairs of cups straddle the cylindrical track (one pair on each side). Each pair projects radially outward from its hub, ends in free outer ends that form a lateral rim, and is clamped together by its nut to define a side track (a nip through which yarn passes).
• Diameter relationship: the cylindrical track's external diameter is at least equal to the diameter of the first side track and at least equal to the diameter of the second side track.
• Tension adjustment: sliding either nut axially changes cup pressure and therefore the tension imparted to yarn running in that side track.
• Mode of use: during "throwing" (stringing/threading-up), the yarn rides on the central cylindrical track; after throwing it is pushed back onto one of the side tracks for normal running.

This gives two capabilities: running two yarns in parallel (one per side track) or performing two successive slackening/tension adjustments on a single yarn (e.g., before and after a heat-treatment oven).

Dependent claims

• Claim 2 — Central track is a separate part interposed between the two hubs, fastened by a screw, and has two peripheral flanges to retain the yarn during throwing. (This is the FIG. 1 embodiment.)
• Claim 3 — Where the track is that separate part, its external diameter is greater than the diameter of each cup's lateral rim (track protrudes beyond the cups).
• Claim 4 — Alternative: the central track is integrally formed with one of the hubs, and its external diameter is less than the diameter of either lateral rim, so the cup rims retain the yarn and act as a ramp to guide the yarn onto the side tracks after throwing. (This is the FIG. 2 embodiment.)

Litigation / Docket Check

• My searches for CAFC 2026 docket activity involving 4,693,068 returned no results, and no USPTO litigation record surfaced. I cannot confirm a negative from an authoritative docket source (I could not reach Patent Center or the CAFC docket system), so I flag this as unverified rather than conclusive.
• Contextual point (not a substitute for a docket check): the patent lapsed on 1991-09-15 for failure to pay maintenance fees, so it has been unenforceable for over three decades. Any 2026 Federal Circuit appeal involving this patent would be highly unusual.
• Cited-by references in the record include US5345790 (Schouten), GB2325246/US6065711 (Sipra), WO2012174514/US9382645 (American Linc), and CN110735200 — these are later citations, not litigation.

Uncertainty flags

• I did not independently confirm the "I.C. ACBF" assignee name beyond the patent record, and the Google Patents rendering of the current-assignee field is truncated/oddly formatted ("I C ACBF"); the assignment record gives the address as Allée Charles Baron, 26000 Valence, France, effective 1986-06-02.
• All bibliographic values above come from the patent record and Justia mirror; I could not cross-verify against USPTO Patent Center directly.