Abstract: The present invention provides a coupling device for coupling a rotary actuator to a mechanical device having a rotatable shaft. The coupling device comprises a spring return module with a first rotatable coupling configured to engage a first portion of the shaft, and a spring engaged with the first rotatable coupling, wherein the first rotatable coupling is rotatable about a rotation axis, and wherein rotation of the rotatable coupling about the rotation axis in a first direction causes mechanical energy to be stored in the spring. The coupling device further comprises an actuator coupling module comprising a second rotatable coupling. The second rotatable coupling is configured to engage a second portion of the shaft, the second rotatable coupling being further engageable with an output of the rotary actuator. The second rotatable coupling is rotatable about the rotation axis, the second rotatable coupling being rotatable relative to the first rotatable coupling about the rotation axis.

Abstract: A gyroscopic stabiliser for stabilising motion of an object includes a support for attaching to the object, a gimbal rotatably supported by the support to be rotatable around a first axis, a flywheel rotatably supported by the gimbal to be rotatable around a second axis relative to the gimbal, orthogonal to the first axis, and a rotary damper. The rotary damper has a chamber containing a damping fluid a vane that is rotatable within the chamber and that is coupled to the gimbal and a flow passage allowing flow of the damping fluid from the chamber on one side of the vane to the chamber on the other side of the vane when the vane is rotated.

Abstract: A gyroscopic stabiliser for stabilising motion of an object, the gyroscopic stabiliser comprising: a support for attaching to the object whose motion is to be stabilised; a gimbal rotatably supported by the support to be rotatable around a first axis relative to the support; and a flywheel rotatably supported by the gimbal to be rotatable around a second axis relative to the gimbal, the second axis being orthogonal to the first axis; wherein the gimbal is rotatably supported by the support at least partly within a maximum width of the gimbal along the first axis; and a maximum width of the gyroscopic stabiliser along the first axis is equal to, or substantially equal to, the maximum width of the gimbal along the first axis.

Abstract: A spring return device comprising a rotatable drive coupling configured for releasably engaging a rotatable drive part on a first side of the device and configured for releasably engaging a rotatable drive part on an opposite second side of the device; a spring engaged with the drive coupling; and a retainer that retains the spring; wherein: rotation of the drive coupling in a first direction relative to the retainer causes mechanical energy to be stored in the spring; and the spring return device comprises an integral locking mechanism that is actuatable between a first state in which rotation of the drive coupling relative to the retainer is allowed and a second state in which rotation of the drive coupling relative to the retainer is prevented.

Abstract: A vane assembly for use in a rotary vane actuator, the vane assembly comprising: a rotatable vane having a first side and a second side; a vane axle connected to the rotatable vane for converting pressure exerted on the rotatable vane into rotational motion; a vane seal on the first side of the rotatable vane, the vane seal being for sealing the rotatable vane; and a side-plate on the first side of the rotatable vane, the side-plate clamping the vane seal in position; wherein the side-plate comprises: an outer part providing an outer surface of the side-plate, the outer part defining an internal volume; and an inner part filling or substantially filling the internal volume defined by the outer part, the inner part being distinct from the outer part.

Abstract: A rotary vane type actuator includes a vane assembly for converting pressure from a pressurized medium within the actuator into rotational movement. The vane assembly has a rotatable vane and a vane seal for preventing leakage of pressurized medium through or around the vane assembly. A side-plate is attached to the rotatable vane and the side-plate has a limiting protrusion that abuts the vane to maintain a gap between the vane and the side-plate so that the seal in the gap is not extruded from between the vane and side-plate.

Abstract: In order to position a rotary actuator, a positioning device is coupled to the actuator. The positioning device has a coupling shaft and springs which respectively surround top and bottom portions of the shaft and are coupled thereto by respective coupling rings. The springs apply oppositely directed torques to the shaft such that one spring urges the shaft in a clockwise direction towards a stop position and the other spring urges the shaft in a anticlockwise direction towards that stop position. The stop position corresponds to an intermediate rotary position of the actuator.

Abstract: A valve actuator adaptor attaches a rotary valve whose mounting is in accordance with ISO 5211/DIN 3337 to a rotary actuator whose mounting is not in accordance with ISO 5211/DIN 3337. The adaptor has first and second mounting surfaces to which the valve head and the actuator are respectively secured and a coupling link extends through the body of the adaptor to interconnect the actuator drive shaft and the valve stem. The adaptor has holes which extend from the first mounting surface to an exposed surface intermediate along the axial length of the actuator. That exposed surface is formed by recesses in the body of the actuator and by partial flanges. Screws or bolts then pass through those holes to the adapter to the valve head, the exposed surface having recesses therein, which recesses are shaped to receive the heads of the screws or bolts, or nuts on the bolts, to prevent them rotating.

Abstract: A declutchable manual override gearbox, comprising a casing, and a drive shaft mounted for rotation within the casing. The drive shaft has an input end and an output end, the input end of the drive shaft adapted to engage the output of a rotary actuator and the output end of the drive shaft adapted for attachment to a device or mechanism, for example the drive linkage for a damper valve, to be driven by the actuator. A manual override is provided for manually rotating the drive shaft, the gearbox also including a clutch arrangment for selectively rendering the manual override inoperative. Attachments associated with a base portion of the casing enable mounting of the gearbox on an underlying support stand.

Abstract: A rotary damper has an inner member located within an outer member and an annular seal between the members enclosing a fluid-filled space bounded in part by mutually adjacent faces of the members. A viscous damping force is thereby generated by relative rotation of the members. The seal has a radially inner rim in sliding engagement with the inner member. A resilient flexible retainer held by the outer member bears on the seal inner rim, flexure of the retainer providing a predetermined axial sealing pressure on the rim. The seal includes a diaphragm portion exposed to atmospheric pressure and deformable to accommodate thermal expansion of the fluid in the sealed space.

Abstract: A liquid dashpot has a casing comprising a main body and bottom cover. The main body contains a liquid chamber which is divided into two discrete spaces by a vane member. One end wall of the chamber has porting passage means formed between the outer face of said wall and the bottom cover to provide restricted communication between the chamber spaces. A flexible diaphragm forms a compensation chamber on the bottom cover subject to atmospheric pressure. The chamber can communicate with the spaces within the liquid chamber through non-return means that block super-atmospheric flow to the compensating chamber. The porting and the communicating passage means between the spaces and the compensating chamber are formed integrally in the die-cast main body and/or the bottom cover, requiring no machining. Assembly is facilitated by bringing together the bottom cover, flexible diaphragm and non-return means as a sub-assembly.

Abstract: A fluid flow device for minimizing the effects of fluctuating pressures on the fluid flow rate has a variable restriction in the fluid path through the device arranged to produce a lesser restriction as the pressure difference between the inlet and outlet of the device increases, and vice versa. This first, variable restriction is formed by an inlet tube and a blocking member. A second, constant restriction for the fluid flow is formed by the tube and a parallel bore through which the tube extends, to produce a pressure drop which creates a pressure differential across a diaphragm balanced by a spring. A change of the pressure differential across the device also changes the pressure differential on the diaphragm, which is connected to the blocking member, so that movement of the diaphragm has the effect of varying the restriction in the manner described to reduce flow rate variations through the device.

Abstract: A fluid-operated actuator (2) is connected to a pumping unit (12) through a control unit (10) in which are mounted control valves (30,32) for regulating the movements of the actuator. The control valves communicate with the actuator and the pumping unit through conduits in replaceable adaptor plates (60a,60b,60c). By changing the adaptor plates, different operating modes of the actuator can be selected. The pumping unit is carried on the control unit through a rotationally adjustable connection to permit it to be mounted upright although the orientation of the actuator and control unit may vary.