Abstract: There is provided an indicator for a torque limiter, comprising one or more resilient members configured to move from an initial, compressed state during normal operation of the torque limiter, to a subsequent, expanded state upon tripping of the torque limiter, to provide a visual indication that the torque limiter has tripped.

Abstract: A torque limiter assembly is disclosed comprising a housing having at least one first engagement member, an input shaft that is rotatable relative to the housing and having at least one second engagement member; and an electromagnet. The electromagnet 10 is arranged and configured such that when activated it generates a magnetic field that moves the at least one first engagement member relative to the at least one second engagement member, such that the first and second engagement members engage each other and stop or inhibit rotation of the input shaft relative to the housing.

Abstract: A spool for a spool valve having a longitudinal axis (L). The spool comprising: a plurality of lands each having a substantially radially extending metering edge and an axially extending circumferential surface; a plurality of grooves separating each of the plurality of the lands; and a guiding section located axially between at least one land and an adjacent groove. The guiding section comprising a plurality of circumferentially spaced guiding surfaces being substantially flush and contiguous with the circumferential surface of the land, wherein the guiding section allows fluid communication between the groove and the metering edge of the land.

Abstract: A spool for a spool valve having a longitudinal axis (L). The spool comprising: a plurality of lands each having a substantially radially extending metering edge and an axially extending circumferential surface; a plurality of grooves separating each of the plurality of the lands; and a guiding section located axially between at least one land and an adjacent groove. The guiding section comprising a plurality of circumferentially spaced guiding surfaces being substantially flush and contiguous with the circumferential surface of the land, wherein the guiding section allows fluid communication between the groove and the metering edge of the land.

Abstract: A torque limiter assembly is disclosed comprising a housing having at least one first engagement member, an input shaft that is rotatable relative to the housing and having at least one second engagement member; and an electromagnet. The electromagnet 10 is arranged and configured such that when activated it generates a magnetic field that moves the at least one first engagement member relative to the at least one second engagement member, such that the first and second engagement members engage each other and stop or inhibit rotation of the input shaft relative to the housing.

Abstract: There is provided an indicator for a torque limiter, comprising one or more resilient members configured to move from an initial, compressed state during normal operation of the torque limiter, to a subsequent, expanded state upon tripping of the torque limiter, to provide a visual indication that the torque limiter has tripped.