Page 66 - Wire Rope News & Sling Technology - February 2019
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         Figure 11: View of the left-hand side of the winch system.
         gear 48 intermeshes between the front two 50 winch system
         gears. Preferably the cable 40 extends from the body 18 be-
         tween the front two driven rollers 50.
           In use, the disclosed apparatus for ensnaring and retriev-
         ing  objects  46  comprises  in  combination  a winch  system
         10, as described above and a processor energy source 12 to
         which the winch system 10 is coupled. The processor energy

                                                              Figure 14: Horizontal sectional view of the winch system.
                                                              ing unless the pawl is retracted.
                                                               Preferably, the cable is wound under tension. In practice,
                                                              is often helpful that the cable be spooled with a minimum
                                                              tension of about 10-15% of the working load. The smaller the
                                                              ratio between the drum diameter and cable diameter, the
                                                              more tension is needed. An insufficient tension allows the
                                                              cable to cut down between lower wraps. This tends to cause
                                                              damage to the cable. An ideal ratio between the drum diam-
         Figure 12: View of the rear of the winch system.     eter and the cable diameter is 25:1 or greater. And ANSI/
                                                              ASME standard sets a minimum of 15:1 for pulling and 18:1
         source 12 has multiple processor driving rollers 14 and some   for lifting. In one set of experiments, the drum diameter was
         embodiments have crab claw-like knives 16.           5 inches, and the wire diameter was 0.63 inches. In that ex-
           As used herein the term “winch” connotes a mechanical   ample, the ratio was 9:1.
         device that is used to pull in (wind up) or let out (wind out)   Relevant to smooth spooling is the angle (fleet angle) at
         or otherwise adjust the “tension” of a rope or wire rope   which  the cable comes  off the sheave and into the winch.
         (also called a “cable” or “wire cable”). In its simplest form,   Preferably, the fleet angle should lie between 0.5° and 1.5°.
         it consists of a spool and an attached hand crank. The   In practice, it is desirable that the winch be mounted so that
         spool can also be called the winch drum. Some designs   its shaft is at a 90 degree angle relative to a line that ex-
         have gear assemblies and can be powered by electric, hy-
         draulic,  pneumatic  or  internal  combustion  drives.  Some
         may include a solenoid brake and/or a mechanical brake
         or ratchet and pawl device that prevents it from unwind-

                                                              Figure 15: Quartering perspective view of an alternate embodiment
         Figure 13: Vertical sectional view of the system.    of the winch system.

         66     Wire Rope News & Sling Technology   February 2019
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