An electrical submersible well pump assembly (ESP) has a spring brake having helical turns mounted between the shaft and one of the housings. The spring brake allows free rotation of the shaft in a driving direction and stops the shaft from rotating in a reverse direction. The spring brake may have one end be affixed to the housing to rotate in unison in both directions. Alternately, the spring brake may have one end affixed to the shaft for rotation with the shaft. Further, the spring brake could be free of being connected to either the shaft or the housing. A shear member may be mounted between the shaft and the housing to prevent any rotation of the shaft during run-in.

An isolating decoupler comprising a shaft, a pulley journalled to the shaft on at least one bearing, a one-way clutch engaged with the shaft, a torsion spring engaged between the one-way clutch and the pulley, the shaft comprises an inner race of the at least one bearing, and the torsion spring having an end welded to the one-way clutch and having another end welded to the pulley.

In a torque limiter of the present invention, a difference is provided between a maximum static frictional force between the coil spring and the first outer circumferential surface and a maximum static frictional force between the coil spring and the second outer circumferential surface such that, when rotational torque in a direction of increasing the diameter of the coil spring and less than a predetermined value is applied to the first or second rotator, the first and second rotators integrally rotate via the coil spring, and one of the first and second rotators relatively rotates relative to the other of the first and second rotators together with the coil spring when the rotational torque is greater the predetermined value.

A pulley structure includes: a cylindrical outer rotation body; an inner rotation body; and a torsion coil spring. The torsion coil spring includes: one end region which is in contact with one rotation body; the other end region which is in contact with the other rotation body; and a middle region. The other rotation body includes: a first contact surface; a facing surface; an inclined surface; and a second contact surface. The facing surface includes a constraining surface connected to the inclined surface. The constraining surface is configured to be capable of constraining the other end region of the torsion coil spring before press fitting so as to prevent a displacement of an axis of the torsion coil spring before the press fitting with respect to an axis of the other rotation body.

In one aspect, a shutter assembly includes a shutter frame and a plurality of louvers supported by the frame. The shutter assembly also includes a louver drive assembly and a motor positioned within the frame. The motor is configured to rotationally drive a drive shaft extending within the frame. Additionally, the shutter assembly includes a clutch assembly rotationally coupled between the drive shaft and the louver drive assembly. The clutch assembly is configured to disengage or decouple the drive shaft from the louver drive assembly when a torque transmitted through the clutch assembly exceeds a given torque threshold.

An isolating decoupler comprising a shaft, a pulley journalled to the shaft on at least one bearing, a one-way clutch engaged with the shaft, a torsion spring engaged between the one-way clutch and the pulley, the shaft comprises an inner race of the at least one bearing, and the torsion spring having an end welded to the one-way clutch and having another end welded to the pulley.

The present invention relates to a pulley structure (1) equipped with an outer rotating body (2), an inner rotating body (3), and a coil spring (4) provided between the outer rotating body (2) and the inner rotating body (3). The coil spring (4) is configured so as to undergo torsional deformation in a diameter-expanding or a diameter-contracting direction, thereby engaging the outer rotating body (2) and the inner rotating body (3) and transmitting torque, and to undergo torsional deformation in the direction opposite the direction in which torque is transmitted, thereby entering a disengaged state in which the coil spring slides with the outer rotating body (2) or the inner rotating body (3), thus interrupting the transmission of torque. The number of windings of the coil spring (4) is in a range between [M-0.125] and M (both inclusive), where M is a natural number.

In a torque limiter of the present invention, a difference is provided between a maximum static frictional force between the coil spring and the first outer circumferential surface and a maximum static frictional force between the coil spring and the second outer circumferential surface such that, when rotational torque in a direction of increasing the diameter of the coil spring and less than a predetermined value is applied to the first or second rotator, the first and second rotators integrally rotate via the coil spring, and one of the first and second rotators relatively rotates relative to the other of the first and second rotators together with the coil spring when the rotational torque is greater the predetermined value.

A torque limiter and no-back assembly comprises an input shaft, an output shaft, a torque limiter provided between the input shaft and the output shaft, the torque limiter comprising a torque sensing element; and a no-back device arranged to brake the output shaft when the torque sensing element senses levels of torque above a threshold level between the input shaft and the output shaft, characterised in that the torque sensing element comprises a torsion spring having ends which are coupled to the input shaft and the output shaft for rotation therewith.

A torque limiting device comprises rotationally mounted input and output shafts, an intermediate drive element rotationally coupled to the input shaft and a plurality of jammer elements mounted between the intermediate drive element and the output shaft. A spring mechanism is connected between the input shaft and the intermediate drive element for aligning the intermediate drive element and the input shaft in a driving configuration in which rotation of the input shaft at a torque below a predetermined threshold is transmitted to the output shaft via the jammer element, but in which torque above the predetermined threshold moves the input shaft rotationally relative to the intermediate drive element against the force of the spring mechanism so as to disengage that jammer elements from driving engagement with the output shaft.