Abstract: A failsafe module comprising an input member (310), an output member (312), and a coupling mechanism for coupling the input member to the output member. The coupling mechanism comprises an intermediate member (316a) movable relative to the output member to energise an energy storage device and a latch mechanism (318, 320) to hold the energy storage device in an energised state. When the latch mechanism is engaged, the input and output members are coupled together and the energy storage device is held in an energised state and isolated from the coupling between the input and output members. When the latch mechanism is released, the energy storage device can release its energy to drive the output member to a predetermined position.

Abstract: A rotating direction change device for a microtome includes: a first shaft arranged in a first fixed position; a first gear wheel non-rotatably mounted to the first shaft; a second shaft movable in a first direction; a second gear wheel non-rotatably mounted to the second shaft; a third shaft movable in a second direction; a third gear wheel non-rotatably mounted to the third shaft; and a first connection part connecting the second shaft and the third shaft such that the second gear wheel is constantly meshed with the third gear wheel, in which the second gear wheel can be driven by the first gear wheel directly or indirectly. Hence, the rotating direction change device has advantages of simple structure and low friction.

Abstract: A stop module for non-jamming end-of-stroke stoppage of a rotary drive actuator includes timing gears to articulate a stopping pawl, and a low inertia, deformable stopping disk arranged to safely dissipate excess rotational kinetic energy of the rotary actuator. The stop module does not rely on friction to stop and dissipate the excess kinetic energy, but instead relies on predictable deformation of a metallic stopping disk which may be provided in a stopping cartridge of the stop module. Use of a deformable element to dissipate excess energy allows the disclosed stop module to be lighter and smaller than conventional end-of-stroke stopping mechanisms.

Abstract: Method and system for controllably administering and/or withdrawing fluid from a patient. In one embodiment, the system may include an infusion needle, a pump adapted to be operably coupled to the infusion needle for creating fluid flow through the infusion needle, and a hands-free switch for activating and/or deactivating the pump.

Abstract: The present disclosure provides a power transmission device in which stress is reduced and a vehicle air-conditioning device. An air-conditioning device has an inside/outside air door. A power transmission device drives the inside/outside air door. The power transmission device has a motor, a gear train, and a cam mechanism. A first gear of the gear train provides a rotatable member. A plurality of lock mechanisms is provided, which stops a rotation of the first gear at one end and/or the other end in a rotation direction of the first gear. The plurality of lock mechanisms provide a plurality of contacts between the first gear and a stationary link cover.

Abstract: A gear device includes an internal gear, a flexible external gear, and a wave generator. The wave generator includes an elliptical cam and a bearing. Grease is applied to the inner circumferential surface of the external gear. A groove is provided along a rotation axis on at least one of the inner circumferential surface of the external gear and an outer circumferential surface of the bearing.

Abstract: A flow rate adjusting valve, in which a needle valve is arranged so as to face a fluid passage of a main body, is equipped with a handle configured to enable a rotational operation to be performed manually, an electric motor configured to be operated remotely, and a motive power transmission mechanism that selectively switches between a rotational operating force of the handle and a driving force of the electric motor, and to transmit the force to the needle valve. The switching is performed by causing the handle to be moved in a direction of an axis of rotation.

Abstract: An operating device for a human-powered vehicle comprises a base member, an operating member, and an assist operating interface. The base member includes a coupling end, a free end, and a grip portion. The coupling end is configured to be coupled to a handlebar. The free end is opposite to the coupling end. The grip portion is provided between the coupling end and the free end. The operating member is pivotally coupled to the base member about a pivot axis. The assist operating interface is configured to receive a first user input indicating that an assist driving unit generates a temporary assist driving force for a limited period corresponding to an operation of the first user input.

Abstract: This disclosure relates to a fuel or charging port door assembly of a motor vehicle. In particular, this disclosure relates to a fuel or charging port door assembly configured to permit a door to open when an override force is applied using an assist tool, for example. An example vehicle includes a door configured to move relative to a body of the vehicle between open and closed positions. The door is a fuel door or a charging port door. The vehicle also includes a lock assembly including a base and a tip. The base is configured to hold the tip during normal operating conditions, and the base and tip are configured to separate upon application of an override force to the door.

Abstract: The invention relates to an improved throttle control system for an aircraft. The throttle system includes providing friction to the throttle to maintain the position of the throttle until the pilot overcomes the friction by using force to move the throttle. The throttle is attached to and positioned about a shaft to provide rotatable movement. The invention uses a first and second friction resistance to maintain the position of the throttle along with an automatic regulating device capable of automatically controlling rotation of the shaft having a geared motor assembly.

Abstract: The invention relates generally to hydraulic rotator. More specifically, the invention relates to a system that provides for the successful three hundred and sixty-degree, clockwise or counterclockwise rotation of heavy weights. The system successfully bears the weight of the equipment, the hydraulic rotator, the attachment to the hydraulic rotator and the materials being targeted by the attachment, as well as the torque load and stress produced by the successful three-hundred-and-sixty-degree rotation.

Abstract: A door operator with high-speed operation and fire escape functions comprises a motor, a high-speed centrifugal brake module, a centrifugal reduction module, a central shaft locking module and a first and second clutch module. In the stationary state, the high-speed centrifugal brake module, centrifugal reduction module and central shaft locking module are connected to each other, and the drive shaft of the motor is locked by the central shaft locking module. In the normal operation, the first clutch module disengages the high-speed centrifugal brake module from the centrifugal reduction module, and the drive shaft is rotatable at high speed. In the event of fire escape, the second clutch module disengages centrifugal reduction module from central shaft locking module, and the drive shaft rotates at a lower speed. The device will provide high-speed rotation under normal operation, and automatically close the door panel at a gradually lowered speed in the event of fire escape.

Abstract: Linear actuators driven by everted ball screw assemblies are described herein. In some examples, the everted ball screw assembly includes a hollow screw shaft with internal threads, a ball cylinder concentrically positioned therein and having external threads, and a plurality of balls sized to fit in a substantially contiguous series along a working pathway that is defined by the space between the internal and external threads. One or more limiters prevent the ball cylinder from rotating. A motor rotates the hollow screw shaft, thereby driving the balls along the pathway and imparting linear motion to the ball cylinder, which is coupled to a connecting rod for actuating a load. The ball cylinder in some examples includes an internal return path with scoop elements that are sized and shaped to guide the balls into the internal return path and then back onto the working pathway.

Abstract: A system including a frame and a pair wheel of assemblies to engage with one or more tracks of a structure. The pair of wheel assemblies include a first hub assembly, having a first wheel and a first attachment mechanism to engage with the one or more tracks of the structure, and a second hub assembly having a second wheel and a second attachment mechanism to engage with the one or more tracks of the structure. The system further includes an elongated rod coupling the first hub assembly to the second hub assembly, where a movement of the elongated rod causes the first attachment mechanism and the second attachment mechanism to engage with the one or more tracks of the structure.

Abstract: An actuating drive (1) for actuating an actuator of a valve, with a motor drive unit (2) for the motorized actuation of the actuator and a manual drive element (3) for the manual actuation of the actuator, wherein an output shaft (13) of the actuating drive (1), which is displaced or can be displaced into an operative connection with the actuator, can be optionally actuated using the motor drive unit (2) or using the manual drive element (3). The actuating drive (1) includes at least one sensor (4, 8, 9, 10, 11), using which a rotational movement of the manual drive element (3) around a rotary axis (5) is detectable, in particular one that has been performed during the motor drive mode.

Abstract: An operating device comprises a base member, an operating member, a user operating portion, and a restriction member. The base member includes a first end portion, a second end portion, and a grip portion. The first end portion is configured to be coupled to a handlebar. The second end portion is opposite to the first end portion. The grip portion is provided between the first end portion and the second end portion. The operating member is pivotally coupled to the base member about a pivot axis. The user operating portion is configured to receive a user input and provided at the second end portion of the base member. The restriction member is at least partly provided, as viewed along the pivot axis, between the user operating portion and the first end portion of the base member to restrict unintentional access to the user operating portion.

Abstract: A fluid control device connectable to a fluid pipe includes an electric motor mechanically connected to a fluid valve configured to open and close the fluid valve. A manual motor disengagement knob is at least partially accessible to a user and mechanically connected to the fluid valve. The knob is configured to manually disengage the mechanical connection between the electric motor and the fluid valve while still engaging the fluid valve allowing the user to manually close or open the fluid valve without the assistance or interference of the electric motor. This is accomplished by a manual over-ride primary shaft translatably connected to a clutch shaft and in turn to the fluid valve, where the shaft in a first position is mechanically connected to the electric motor and in a second position the shaft is not mechanically connected to the electric motor.

Abstract: A piston pump assembly for a hydraulic power vehicle braking system including an electric motor, a planetary gear set, a helical gear, and a piston which is displaceable in a cylinder. To prevent the piston from rotating in the cylinder, cylinder pins are situated in grooves at an inner side of the cylinder and engage with the recesses in a flange of the piston. Due to reshaping, the grooves are closed at one end, so that the cylinder pins are axially secured.

Abstract: A reverse rotation prevention mechanism is provided on a torque transmission path between an output shaft and a driving shaft of a motor. The reverse rotation prevention mechanism includes: a first frictional force generation unit configured to inhibit a lock plate provided on the torque transmission path from rotating relative to another member when an external force is exerted on the output shaft; and a second frictional force generation unit configured to generate a braking force that prevents reverse rotation when an external force is exerted on the output shaft by causing a portion of the lock plate to be pressed. The first frictional force generation unit is provided in an area different from the second frictional force generation unit.

Abstract: A dual-mode turret system includes a turret base operable by a motor drive of the turret system, a cylindrical sleeve secured to the turret base, a mounting cylinder disposed in the cylindrical sleeve, and a frame secured to the mounting cylinder, wherein the frame is adapted to hold a weapon. The dual-mode turret system also includes a locking apparatus that when engaged prevents the mounting cylinder from rotating independently of the cylindrical sleeve, a controller, and an input device coupled to the controller. Rotation of the frame is manually adjustable when the locking apparatus is disengaged, and the rotation of the frame is adjusted by the controller in response to commands received from the input device when the locking apparatus is engaged.

Abstract: Disclosed herein is a refrigerator which includes a body, a door configured to open and close a storage compartment and a door opening and closing apparatus. The door opening and closing apparatus includes a pair of intermittent gears configured to transmit the power from a first gear to a second gear of the door opening and closing apparatus and configured to prevent an external force from being transmitted from the second gear to the first gear while the external force is applied to open and close the door. This configuration, among other benefits, improves the durability of a door opening and closing apparatus.

Abstract: Operating a machine including a continuously variable transmission (CVT) includes operating an engine of the machine at a lower engine speed, receiving data indicative of an expected increase in load on the engine, and commanding increasing the engine speed responsive to the data. The engine is operated at a higher engine speed responsive to the commanded increase, with the operation at the higher engine speed being initiated proactively so as to limit retarding a ground speed of the machine. Related control logic and machine structure is also disclosed.

Abstract: A vehicle shift control lever device may be provided that includes: a transmission rod; a detent pin which is disposed under the transmission rod in such a manner as to move in up-and-down and back-and-forth directions; and a groove member which has a groove formed therein which guides the detent pin. The groove member includes a first stable position “a” at which the detent pin is placed when a shift position is R, D, M or N-shift positions and a second stable position “b” at which the detent pin is placed when the shift position is a P-shift position.

Abstract: A thermostat valve includes a housing with several cooling fluid connections, at least two hollow valve elements mounted rotatably next to one another in the housing on a common rotational shaft, each having at least one opening selectively couplable to one or more of the cooling fluid connections by way of rotation of the valve elements, and a rotational drive for a first of the valve elements can be driven rotationally in the housing, a second of the valve elements can be selectively coupled to or decoupled from the first valve element, the second valve element driven rotationally, when it is coupled to the first valve element, and a coupling element mounted axially movably on the rotational shaft, and a coupling drive by way of which the coupling element can be moved axially on the rotational shaft between a coupling position and a decoupling position.

Abstract: The invention relates to an aircraft cockpit center pedestal for the attachment of control and instrumentation equipment for this aircraft, wherein the center pedestal includes an equipment module including controls connected to at least one first electrical connector, and a single-piece frame including an upper face provided with a recess including at least one second electrical connector installed at the bottom of the recess and connected to computers onboard this aircraft in which this equipment module is installed, the at least one first electrical connector of the equipment module being inserted into at least one second electrical connector so as to connect the controls of the equipment module and these onboard computers. The invention also relates to an aircraft including such a pedestal.

Abstract: A method for regulating an energy recovery in a pedal-driven vehicle having a crank drive, an electric auxiliary drive and a rechargeable energy source includes: detecting a direction of rotation of the crank drive, and recovery of energy and storage of energy in the energy source when the direction of rotation of the crank drive is directed backward.

Abstract: A system, in certain embodiments, includes a gate valve including a gate disposed within a valve body. The gate valve also includes a motorized ball screw actuator having an actuating rod assembly directly coupled to the gate. The motorized ball screw actuator is configured to linearly actuate the actuating rod assembly to drive the gate between an open position and a closed position.

Abstract: A tunnel raceway type ball screw assembly includes a screw nut having an inner thread groove, a screw shaft inserted through the screw nut and including outer grooves, a mounting groove extending across the outer grooves and a first reflow groove in radial communication with the mounting groove, and a reflow component mounted in the mounting groove of the screw shaft and including a rolling groove connected with the outer grooves to form an outer thread that defines with the inner thread groove a spiral channel therebetween and a second reflow groove that defines with the first reflow groove a reflow channel therebetween in communication with the spiral channel. Thus, multiple balls can be cycled in the spiral channel and the reflow channel.

Abstract: A hydraulically powered switch machine having power and manual operating modes, and a dual disconnect mechanism. In power operation mode, the machine may be operated remotely, or using controls located on or near the machine. In the event of power failure, the machine may be operated manually. The dual disconnect mechanism physically disconnects the powered throw mechanism when the machine is operating in manual mode and physically disconnects the manual throw mechanism when the machine is operating in power mode, in both cases preventing unexpected movement of the manual throw mechanism.

Abstract: A retractable awning having a roller, a flexible canopy having one end secured to the roller and rollable onto the roller, and a motor operable to rotate the roller to roll the flexible canopy onto or off the roller. The motor includes a protective housing, with a manual motor override on the motor within the housing. An aperture in the housing proximate the override is aligned with and permits access to the override through the aperture.

Abstract: A linear actuator (1) includes an electrical driving mechanism (10), a lead screw (20), an outer tube (30), a telescopic tube (40) and an arm driven mechanism (50). The arm driven mechanism (50) comprises an arm (51), a driving nut (52), a telescopic sleeve (53), a first washer (54), a nut-tube (55) and a second washer (56). The arm (51) is provided with a handle (511) and a sleeve (512), and the sleeve (512) links with the lead screw (20). An outer peripheral of the telescopic sleeve (53) provided with a plural of screws for screwing with the telescopic tube (40). The nut-tube (55) links with the driving nut (52) for moving together. When the handle (511) rotates, the linear actuator (1) can be operated.

Abstract: The invention relates to a mechanism for converting a rotary motion originating from a rotary energy generator (1) into a longitudinal motion of a carriage (25) that is adapted for attachment to a covering, such that said rotary motion will result in a longitudinal displacement of the covering, the mechanism comprising one or more spindle sections (2, 3, 4, 5) drivingly connected at a longitudinal end of at least one of said spindle sections via a gear means (7; 9; 22, 23, 24, 27) to said rotary energy generator (1). The invention further relates to a drive system for coverings comprising mechanisms according to the invention. The invention further relates to a covering system for covering a surface portion such as a window, glass door or the like, of a building.

Abstract: A powered dispensing tool includes a housing, a motor at least partially positioned within the housing, a rack operably coupled to the motor for powered translation, and a transmission selectively operably coupling the motor and the rack. The transmission includes an output shaft rotatable in response to rotation of the motor, and an output member drivably coupled to the rack and supported on the output shaft for relative rotation therewith. The transmission also includes a clutch member coupled for co-rotation with the output shaft and movable along the output shaft between a first position, in which the clutch member is engaged with the output member for transferring torque from the output shaft to the output member, and a second position, in which the clutch member is disengaged from the output member to inhibit torque transfer between the output shaft and the output member.

Abstract: A motor drive unit assembly for a motorized drapery system having a drapery fabric can include a motor having a drive shaft, an output member rotatable about a drive axis, such that rotation of the output member about the drive axis causes the drapery fabric to move, and a clutch member operatively coupled between the drive shaft of the motor and the output member. The clutch member is configured to automatically couple the output member to the drive shaft such that rotation of the motor drive shaft causes the output member to rotate about the drive axis when the motor drives the drive shaft. The clutch member is further configured to automatically decouple the output member from the motor drive shaft so that the output member rotates about the drive axis relative to the motor drive shaft when the output member is manually driven.

Abstract: A door machine having an electric motor and a chain disk locking mechanism. The chain disk locking mechanism includes a chain disk, an engaging rotary block, a stationary shaft and a plurality of moving pins. When the chain disk is pulled to rotate, the fixed pins of the chain disk press the moving pins so as to push the engaging rotary block to rotate with the stationary shaft together. When the stationary shaft is pulled to rotate, the engaging rotary block prohibits the moving pins from rotation. When the chain disk is pulled manually, the rolling door can be rolled upward or downward; when cease pulling the chain disk, braking is immediately effected so as to prevent the rolling door from moving upward or downward. Hence, the clutch mechanism can be omitted for cost saving and the structure of the mechanism can be simplified.

Abstract: The drive for a pedal vehicle, particularly for children, comprising a drive axle having two drive wheels, further comprising a pedal crank the pinion of which is connected via a chain to a further pinion which is firmly seated on the drive axle, is characterized in that the one drive wheel is connected via a freewheeling mechanism in both directions to the drive axle, and that the other drive wheel is freely rotatably seated on the drive axle and is drivable by an electric motor.

Abstract: A method of operating a double clutch that is actuated by a hydrostatic actuating system having two clutch actuators assigned to two individual clutches and each clutch actuator including a pressure sensor for sensing the operating pressure of the respective clutch actuator, the method having the step of limiting a total actuating force of the double clutch in the event of a fault using the pressure values sensed by the pressure sensors.

Abstract: A rotator drive connection for a gas turbine engine accessory box has a shaft connected to be driven by a main shaft in a gas turbine engine through a gear train. A first drive connection allows selective drive of the shaft. A biased drive member includes a second drive connection selectively brought into contact with the first drive connection to allow rotation of the main shaft. The biased drive member biases the second drive connection out of contact with the first drive connection. A gas turbine engine accessory box and a method of borescopic inspection are also disclosed and claimed.

Abstract: A hand pulling drive mechanism includes a hand drive device and a shaft connected with the hand drive device. The mechanism further includes a gear pair, a rotation propelling device connected with the shaft, and an eccentric pulling device including a shaft pin placed on the shaft and a torsion jacket pivotally connected to the shaft and rotated relative to the shaft pin. The gear pair includes a drive gear sleeved on the shaft for switching, and a follower gear secured to a motor shaft. The rotation propelling device is connected with the drive gear. The torsion jacket and the drive gear pull the torsion jacket through eccentric rotation of the shaft pin when the shaft is rotated, so that the drive gear moves in an axial direction and the follower drive engages with and disengages from the drive gear.

Abstract: An integrated brake and chain disk device for a door operator includes an electrical motor with a main shaft coupled to a gear box for rolling a rolling door through an output shaft of the gear box; a brake device for braking the main shaft; a chain disk device for manually rotating the main shaft upon power failure; a clutch device which disengages the intermediate shaft from the chain disk device or engages the intermediate shaft with the chain disk device. The brake device includes at least one torsion spring fitting on a fixed hub. The torsion spring tightly fits on the hub and becomes immovable when a force in a spiral direction of the torsion spring is exerted on either end of the torsion spring, and can be released from the hub when a force in a direction opposite to the spiral direction of the torsion spring is exerted on either end of the torsion spring. In this way, the brake device and the chain disk device are integrated.

Abstract: There is provided a power source device capable of obtaining power not only when springs or the like return but also when a handle for winding up the springs or the like are operated. The power source device comprises a main shaft connected to both the handle and a main power generation device, an auxiliary shaft connected to an auxiliary power generation device arranged side by side in parallel with the main shaft, the main spring and the auxiliary spring requiring less load to wind up than the main spring being installed between the main shaft and the auxiliary shaft via drums such that accumulation and release of elastic force of the springs are alternated on both shafts, wherein when the main shaft is normally rotated by the handle, elastic force accumulated in the auxiliary spring is applied in the direction of rotation of the main shaft as releasing force.

Abstract: A drive arrangement for a shaft has a module carried by the shaft and including a motor, a driven wheel and a drive wheel. The motor, gearbox and drive wheel are carried on a slider plate which can slide transverse to the axis of the shaft. A front plate is fixed transverse to the axis of the shaft. A Bowden cable has its sheath attached to the front plate, and its inner cable attached to the slider plate, so that manipulation of the Bowden cable at a remote location allows force to be applied between the plates either tightening the belt to apply drive from the motor to the shaft, or releasing tension in the belt, to disengage the drive.

Abstract: A manual drive is provided for an electric-motor actuating drive for controlling fittings for process automation. The manual drive includes a constraining transmission, whose output drive can be operatively connected for braking purposes to the motor shaft, such that force can be transmitted, via a detachable clutch which is operable electrically.

Abstract: An integrated brake and chain disk device for a door operator includes an electrical motor with a main shaft coupled to a gear box for rolling a rolling door through an output shaft of the gear box; a brake device for braking the main shaft; a chain disk device for manually rotating the main shaft upon power failure; a clutch device which disengages the intermediate shaft from the chain disk device or engages the intermediate shaft with the chain disk device. The brake device includes at least one torsion spring fitting on a fixed hub. The torsion spring tightly fits on the hub and becomes immovable when a force in a spiral direction of the torsion spring is exerted on either end of the torsion spring, and can be released from the hub when a force in a direction opposite to the spiral direction of the torsion spring is exerted on either end of the torsion spring. In this way, the brake device and the chain disk device are integrated.

Abstract: An operating device for selecting shift stages in a shift-by-wire gearbox. The device comprises a selector lever which is movable between a drive gear position and a park position, and a locking device with a spring-loaded detent pin and a lock-in gate. An actuator device, that moves the selector lever, comprises a disengagement device. A detent pin and a lock-in gate can be brought, via a disengagement device, from a first relative position, in which the detent pin engages a shifting track of the lock-in gate, into another relative position, in which the detent pin disengages the shifting track. The operating device facilitates simple and safe actuator-induced return of the selector lever, into the park position, and offers the driver reliable optic and tactile feedback about the actual shift condition of the transmission.

Abstract: A drive for a movable furniture element has an actuating element for moving the furniture element and a motor for driving the actuating element. The actuating element and the furniture element may at times be moved independently of one another, and a position measurement system is provided for determining both the position of the actuating element and the position of the furniture element.

Abstract: An electric motor actuating drive for actuating elements designed such that the drive train, which is formed from spur gears, is not self-locking, and such that a braking spring is operatively connected to a gearbox stage upstream of the output-drive element of the drive train, such that, when the drive motor is disconnected, the actuating element is effectively prevented from being moved even when attempts are made to move it by external force or by extreme force. Furthermore, the actuating drive is in the form of a spring return and is equipped with a drive spring which is arranged such that the load on it is removed in the event of electrical power failure, and it therefore acts as a drive element. Furthermore, the electrical components are arranged in an end-face housing wall for a compact design.

Abstract: A torque limiter is provided with a first plate that rotates a second plate via a plurality of balls. The second plate shares the same axis as the first plate. Each ball is suitable for escaping from a respective housing in order to cease driving the second plate when the torque exceeds a predetermined threshold. Each housing includes a first orifice and a second orifice facing each other and formed respectively in the first plate and in the second plate. The torque limiter is remarkable in that it includes first and second distinct inlets for causing the first plate to turn about its axis.

Abstract: A retarding system for a work machine having a power source, a transmission, and a manually operated braking mechanism is disclosed. The retarding system has an engine retarder associated with the power source and a controller in communication with the transmission, the manually operated braking mechanism, and the engine retarder. The controller is configured to determine a deceleration rate of the work machine and compare the deceleration rate of the work machine to a predetermined threshold rate. The controller is also configured to determined if the manually operated braking mechanism is active and to cause the transmission to downshift if the deceleration rate is less than the predetermined threshold rate and the manually operated braking mechanism is determined to be active. The controller is further configured to prevent the transmission from downshifting if the deceleration rate is less than the predetermined threshold rate and the manually operated braking mechanism is determined to be inactive.

Abstract: An auxiliary operating device for manually operating a normally motor-operated closure between open and closed positions, the device comprising a shaft, a driving member mounted to the shaft and displaceable between an idle position and an operational position wherein the driving member is operatively coupled to the closure. The device further comprises a manual actuator for first displacing the driving member from its idle position to its operational position and then driving the driving member in order to displace the closure. The actuator can be advantageously mounted at either end portions of the shaft irrespectively of the position of the driving member on the shaft.