In an aspect, an automotive air conditioning assembly comprising a scroll compressor and a wrap spring clutch. The wrap spring clutch enables the use of a comparatively smaller pulley (a diameter of at most 85 mm) which comparatively increases the compressor speed and hence cooling capacity at a given engine speed. The clutch requires low power (e.g. less than 5 Watts) for continuous operation.

A driving force transmission mechanism includes a first transmission member and a second transmission member that are arranged on an identical rotational center axis. The first transmission member includes one or more transmission claws engaged with the second transmission member. The transmission claw includes, at a position away from the rotational center axis, a fixing portion with respect to the first transmission member, and extends in a direction crossing a direction directed from the fixing portion to the rotational center axis. The second transmission member includes one or more stoppers engaged with a tip end of the transmission claw and one or more holding portions engaged with a side of the transmission claw, which faces the rotational center axis.

A driving force transmission mechanism includes a first transmission member and a second transmission member that are arranged on an identical rotational center axis. The first transmission member includes one or more transmission claws engaged with the second transmission member. The transmission claw includes, at a position away from the rotational center axis, a fixing portion with respect to the first transmission member, and extends in a direction crossing a direction directed from the fixing portion to the rotational center axis. The second transmission member includes one or more stoppers engaged with a tip end of the transmission claw and one or more holding portions engaged with a side of the transmission claw, which faces the rotational center axis.

A torque limiter (120) includes a coil spring (124), an inner shaft which is connected to a drive shaft (58) and is disposed to be inserted into a coil portion of the coil spring (124) so that the coil portion of the coil spring (124) is configured to come into close contact with an outer peripheral surface, a bottomed cylindrical outer member (122) which is disposed at the outside of the coil portion with a gap interposed therebetween and is provided relatively rotatable with respect to the inner shaft so that both end portions of a wire forming the coil spring (124) are locked thereto, and a drive gear (123) which is integrally formed with a plate portion (122a) of the outer member (122) and is configured to transmit a rotational force to the screw shaft.

A torque limiter (120) includes a coil spring (124), an inner shaft which is connected to a drive shaft (58) and is disposed to be inserted into a coil portion of the coil spring (124) so that the coil portion of the coil spring (124) is configured to come into close contact with an outer peripheral surface, a bottomed cylindrical outer member (122) which is disposed at the outside of the coil portion with a gap interposed therebetween and is provided relatively rotatable with respect to the inner shaft so that both end portions of a wire forming the coil spring (124) are locked thereto, and a drive gear (123) which is integrally formed with a plate portion (122a) of the outer member (122) and is configured to transmit a rotational force to the screw shaft.

An operating system for use with an architectural-structure covering for moving a covering portion of the architectural-structure covering between an extended position and a retracted position is disclosed. The operating system may include a drive mechanism (e.g., a drive spool), a driven member operatively coupled to the drive mechanism, a clutch mechanism (e.g., a wrap spring) operatively coupled to the drive mechanism and the driven member, and a collar operatively associated with the clutch mechanism. The collar may be adapted and configured to receive an end portion of the clutch mechanism so that the end portion of the clutch mechanism is encased by the collar.

A rotary clutch uses a wrap spring clutch. An actuator generates a drag force to control the wrap spring clutch to engage or disengage the clutch. The actuator includes an electromagnet, a two-component armature and an axial return spring. The two-component armature includes first and second components threadingly connected one another for relative axial translation as they rotate relative to one another, and an angular position biasing member connecting them. The second component translates axially under magnetic force from the electromagnet, and when stopped by the electromagnet the first armature component translates axially due to their threaded connection. Due to the previous axial movement of the floating component the translation of the first armature component occurs in conditions where the air gap and reluctance of a magnetic circuit is reduced compared to the prior art, and thus the overall strength of the applied magnetic field can be comparatively reduced.

A rotary clutch uses a wrap spring clutch. An actuator generates a drag force to control the wrap spring clutch to engage or disengage the clutch. The actuator includes an electromagnet, a two-component armature and an axial return spring. The two-component armature includes first and second components threadingly connected one another for relative axial translation as they rotate relative to one another, and an angular position biasing member connecting them. The second component translates axially under magnetic force from the electromagnet, and when stopped by the electromagnet the first armature component translates axially due to their threaded connection. Due to the previous axial movement of the floating component the translation of the first armature component occurs in conditions where the air gap and reluctance of a magnetic circuit is reduced compared to the prior art, and thus the overall strength of the applied magnetic field can be comparatively reduced.

Methods and apparatus related to electrolaminate clutches and transmissions are disclosed. A device can include: an input shaft that can be coupled to an electrolaminate sheet; an output shaft that can be coupled rigidly to a spring positioned over the input shaft, where the spring includes a tab that fits a groove of a spring capture ring that can be positioned over the input shaft; and a drum connected to an electrical ground between the electrolaminate sheet and the spring capture ring, where the drum can be coupled rigidly to the spring capture ring. Then, when a voltage is applied to the electrolaminate sheet, the electrolaminate sheet can clamp to the drum and impart rotation of the input shaft to the drum. The imparted rotation can cause the spring capture ring and the spring to rotate and clamp down on the input shaft, imparting rotation to the output shaft.

In an aspect, the invention is directed to a clutched device that includes a clutch input member, a clutch output member, and a wrap spring clutch. The wrap spring clutch is engageable with the clutch input member and the clutch output member and has a radially outer surface and a radially inner surface. One of the radially outer and inner surfaces is engageable with a clutch engagement surface on one of the clutch input member and the clutch output member. The clutch engagement surface has a surface finish that includes peaks and valleys, wherein the peaks engage the wrap spring clutch and each have a selected width.