Adjustable viscous shear coupling

Abstract

An adjustable viscous shear coupling comprises a housing containing a viscous fluid therein, an inner part such as a shaft extending into the housing, a set of outer disks non-rotatably connected to the housing, a set of inner disks non-rotatably connected to the inner part, the inner disks and the outer disks being interleaved so that adjacent disks are separated by a gap, and an axially movable piston which acts on the disks to adjust the width of the gaps. The adjustable viscous shear coupling is constructed so that sealing intervals are formed between the outer disks and the inner part and between the inner disks and the housing so that the overflow of viscous fluid from one gap to another is greatly inhibited. In a preferred embodiment, the adjustable viscous shear coupling includes inner choke elements disposed between the outer disks and the inner part, and outer choke elements disposed between the inner disks and the housing, the choke elements creating the sealing intervals.

Dependencies are inferred from the claim text.