Abstract: A portable descent device for lowering an object at a controlled speed has a rotating spool carrying wrapped cable mounted within a casing. The spool rotates about a fixed shaft in a sealed chamber containing a viscous liquid. A series of alternating, closely adjacent, flat, parallel, rotatable and non-rotatable discs are mounted in the sealed chamber and extend radially of the shaft. As cable is payed out from the device, movement of the rotatable discs through the fluid creates a frictional drag which slows the descent rate to a relatively constant, safe speed.

Abstract: A casing incorporates a spool having a cable wound thereon. One end of the cable is fixed to the spool and the other end passes from the casing. A safety belt is secured to the casing and arranged to support a human body. The extending free end of the cable terminates in a hook or other device for attaching the same to a high rise building. In the event of fire or other emergency, a person can lower himself by paying out the cable from the casing. Appropriate viscous fluid in the casing provides a drag so that the rate of descent is controlled.

Abstract: A fire escape device includes a portable spool journalled in a casing including a safety hook for suspending the spool from an eyebolt installed in elevated relation to ground level. A support line is wound about the spool and includes a body harness at its free end. For retarding rapid descent of a human body in the harness, a cylindrical rotor extends coaxially from the spool for joint rotation therewith. The spool lies within a cylindrical cup supported by the casing defining a fluid tight chamber coaxially about the rotor. The chamber is filled with a viscous fluid to provide viscous friction forces in the circumference of the rotor. The viscous fluid is dimethyl siloxane having a density between 0.65.times.10.sup.6 and 2.0 .times. 10.sup.6 centistokes and the annular gap between the rotor and the cup is chosen to achieve a descent rate ranging between 3 and 5 feet per second for a human body weighing 250 pounds.