A method for managing avionic data between a flight management system FMS and one or more clients, the FMS comprising resources accessible through avionic services Ci (1,n); the execution of the Ci (1,n) determining an avionic functionality Fj (1,m); each of the Fj (1,m) associated with an intrusiveness parameter Ik and a criticality parameter Ck; the method comprises the steps of receiving a request specifying the call to an Fj (1,m); and determining a predefined execution right for a Ci (1,n), dependent on the predefined intrusiveness and/or criticality parameters associated with the Fj (1,m). Developments describe particularly the comparison of the execution rights, notice of a rejection, various avionic services and functionalities, the management of criticality ranges, consideration of the flight context, etc. Software and system aspects are described (e.g. equipment of EFB type).

The present invention provides a flight control method for an aerial vehicle and a related device. The method may comprises receiving flight indication data under a current environment, the flight indication data including flight indication data detected by another aerial vehicle or provided by an external storage device; generating a flight control instruction according to the received flight indication data to control a flight of the aerial vehicle. An embodiment of the present invention may store and manage the flight indication data acquired by various aerial vehicles, so as to provide the support of related flight indication data to some requesting aerial vehicles, to enable the requesting aerial vehicles to perform operations such as obstacle avoidance, safe path planning and finding landing places based on the flight indication data.

The general field of the invention is that of methods of three-dimensional graphical representation of a landing runway on a viewing screen of an onboard viewing system for aircraft, the said graphical representation being displayed in a synthetic view of an exterior landscape. The graphical representation according to the invention comprises a line disposed along the axis of the runway, the said line being a straight stripe inclined by an angle of between one and a few degrees with respect to the horizontal, the said line beginning at the runway threshold.

A positive electrode active material includes: secondary particles obtained by aggregation of a plurality of primary particles. The primary particles include, core particles including a lithium composite oxide, and a layer that is provided on surfaces of the core particles and includes a lithium composite oxide. The lithium composite oxide included in the core particles and the lithium composite oxide included in the layer have the same composition or almost the same composition, and crystallinity of the lithium composite oxide included in the layer is lower than crystallinity of the lithium composite oxide included in the core particles.

The present invention provides a manually powered drive assembly for a vehicle. A foot crank winds a helical torsion spring through a system of shafts and sprockets in a first direction. By releasing a brake applied to a wheel, or wheels, of the vehicle, the wound spring transfers a rotational movement from a spring shaft to a freewheel sprocket coaxially aligned with the axle supporting a wheel, so that the rotational movement upon the wheel assists a user in manually moving the vehicle. The drive assembly may be advantageously used with a wheelbarrow to assist in building up momentum for moving heavy loads.

A vehicle passive entry side door latch release system engageable with a release cable connected a door latch includes a moveable linkage assembly engageable with the cable, and a motor including an output shaft engaged with a tensioning gear for driving a ratcheting gearwheel rotatably affixed to a coil spring, with the gearwheel including external teeth engageable with a rack affixed to the linkage to move the cable to unlatch the door latch. A pivotable ratcheting pawl may be engageable with the gearwheel to allow or prevent rotation of the gearwheel. Operation of the motor may drive the gear to drive the gearwheel in a rotary direction to energize the spring, and disengagement of the pawl from the gearwheel may allow stored energy in the spring to drive the gearwheel in an opposite rotary direction to thereby drive the rack to move the cable to unlatch the door latch.

When a rotational shaft of a gear speed reducer is rotated, a small-diameter gear of a first gear is held in mesh with first internal teeth of a fixed gear and a large-diameter gear of the first gear is held in mesh with second internal teeth of a second gear. The first gear and the second gear comprise cycloidal gears, respectively, and transmit rotational drive power to the second gear. The rotational drive power is output from an output shaft of the second gear. The gear speed reducer has a default mechanism for holding the output shaft at a predetermined angular position when an electric signal applied to an actuator is interrupted, and a self-lock function for preventing drive power applied from the output shaft from being transmitted to the actuator.

This application includes a number of embodiments of a spring powered toothbrush for cleaning teeth. A wind-up spring is located in the base of the toothbrush which spring provides power for a gear train including a drive shaft assembly that is designed to bring about rapid movement of the brush portion of the toothbrush to aid in cleaning the teeth. The drive mechanism is controlled by a spring biased push button in the toothbrush housing. In one version the brush portion of the toothbrush includes a rotatable brush section that is gear driven by the drive shaft. In another version the upper portion of the toothbrush is vibrated by an offset weight connected to the drive shaft and in a third version the drive shaft includes an offset weight that acts to oscillate a movable brush section by intermittent engagement between the; weight and brush section.

A driving apparatus for driving a functional body mounted on a vehicle comprises a power supply, an electric motor, and a driving means. The electric motor is connected to the power supply and is started by a power feed from the power supply. The driving means has a spring motor and is connected to the electric motor and the functional body. The driving means accumulates an urging force by winding up the spring motor by the electric motor and driving the functional body by the urging force. This driving apparatus can automatically drive the functional body, can be manufactured inexpensively, and accumulates a driving force to the functional body without giving burdens to an occupant.

A pumping unit system having vertical sampson post, a walking beam pivotally supported at the upper end of the sampson post and a horsehead affixed at a forward end thereof that supports a reciprocated sucker rod string, including a gear reducer mounted at selectable positions on the walking beam and having a horizontally extending drive shaft, a crank arm affixed to the drive shaft the spacing between a selectable length pitman rod having a first end secured to said crank arm and a second end having a pitman bearing that is selectably mountable to a plurality of pitman bearing locations and a prime mover connected to the gear reducer and wherein the characteristics of the pumping unit are determined by the selectable position of the gear reducer, the selectable length of the crank arm, the selectable length of the pitman rod, and the selectable pitman bearing location.

Luggage or carrying container (1) having an interface (10) for cooperating with one or more electronic and/or wireless devices (20, 22, 24, 26, 28), a rechargeable power source (30), an integrated antenna (40), and a wireless communication system (50). The luggage (1) allows a user to better manage various electronic devices/accessories in terms of space, efficiency and operation during travel.

An actuator and door latch system incorporating the same. The actuator moves a door latch between locked and unlocked positions with rapidity using a gear train directly coupled to an actuator motor or energy stored in an energy storage element such as a spring.

A mechanical rotational drive has a bar-like torsion element, whereby the torsion element is firmly clamped with a first end in a bearing device. The torsion element can be pivoted with a second free end with respect to the clamped end about the longitudinal axis, forming a rotation axis, of the torsion element between a relaxed position and a tensioned position, whereby the length of the torsion element is reduced with respect to the relaxed position when the torsion element is brought into its tensioned position. A device for transmitting a torque into the torsion element or out of the torsion element is provided in the area of the free end, and a damping device is arranged in the axial direction of the torsion element at a fixed distance from the bearing device and adjacent to the free end of the torsion element, and a damping part is provided on the torsion element in the area of the free end of the torsion element, which damping part in the relaxed position is in friction engagement with the damping device and which in the tensioned position is not engaged with the damping device.

A machine for generating mechanical energy and functioning on the principle of exploitation of centrifugal forces of masses being displaced along a closed mechanical circuit over at least a curved section of the circuit. Optionally, the machines also functions on the principle of energy gain caused by masses falling under the influence of gravity in the closed circuit that is permanently maintained in a state of dynamic unbalance with an input, continuous or not, of external energy.

A force amplifier has a guide track, a non-locking screw threadedly engaging the track to spirally move in response to an axial input force applied to the proximal end of the non-locking screw. The force amplifier includes a compliant component coupled to the non-locking screw by one end and to a self-locking screw by the other end. The compliant component is configured to transmit a torque generated by the non-locking screw to the self-locking screw, which is actuated to move spirally along the track while generating an axial output force greater than the input force.

An electrical generator is driven by gravitational force provided by a plurality of pairs of water tanks. Each pair of water tanks is suspended by an elongated chain supported by a series of pulleys. The water tanks in each pair of water tanks move between an upper position and a lower position alternately by filling selected ones of the water tanks with water and draining from the other selected ones of the water tanks. The vertical movement of the water tanks alternately filled with water is translated by ratchet wheels and bevel gear wheels to rotate the electrical generator in the same direction for generating the electrical power.

A spring-based mechanism for saving labor of a bicycle rider is disclosed and in one embodiment includes an axle operatively connected to a chain wheel and a first set of bearings via a gear assembly; a housing for mounting a shaft therein wherein the first set of bearings is provided at one end of the shaft; a second set of bearings provided at the other end of the shaft; a spring in the housing and having one end attached to one end of the shaft and the other end attached to the other end of the housing; and a clutch provided externally of the other end of the housing, the clutch being operatively connected to the second set of bearings and including a lock lever. The mechanism can store elastic force by counterclockwise pedaling and release the stored energy by disengaging a clutch from the mechanism when riding uphill.

A rigid arm pendulum is combined with a helical device attached to the pendulum horizontal axle to provide a double reciprocating action. While the pendulum reciprocates in rotary fashion about the axle, describing successive arcs of less than 360 degrees, the axle simultaneously produces a reciprocating action about its longitudinal centerline. A pumping action is thereby developed in line with the longitudinal centerline of the axle. This pumping (linear reciprocating) action can be utilized for a variety of requirements, including a hydraulic pump and a system to drive an electric generator.

A motor mounted on a structural support with a pivot at its center line which comprises a cylindrical vessel for holding a fluid in a closed system and in which a buoyant cylinder containing a lighter fluid is allowed to free float so that a cable attached to either end of the buoyant cylinder may be used to transfer energy to a energy storage unit, a crank or a generator. Two moment arms having a weight attached at the exterior end and inside attachably connected to the surface of two drive pistons that operate in pressure tanks which force a compressed gas against the pistons through pre-sequenced automatic activated valves to extend or retract the moment arms at the end of a cycle. The motor then becomes top heavy and rotates 180 degrees by gravity and relocks in place to repeat the cycle.

A concentric cross mechanism for transiting torsion includes a main body unit of a concentric cross mechanism, a main body unit of the torsion-driven mechanism, a main body unit of the force-generating mechanism, and a restriction device. A center point is defined by crossing a vertical concentric axis and a horizontal concentric axis. The axle of the driven bevel gear and the scroll springs spin reversely with the axle of the torsion-generating bevel gear. The first bevel gear is provided for outputting the torsion on the upper and bottom ends thereof. Furthermore, when the rotary rod connected with one side of the torsion output axle is disposed between the positioning block and the positioning post, the door is driven by the other side of the torsion output axle to swing in a predetermined angle.

An actuator comprises an elongated shape-memory element wound around a first element and having one first end connected to the first element and one second end connected to a second element. Heating means are provided for heating the shape-memory element in order to obtain a displacement of one of the ends thereof. The elongated shape-memory element is guided so that it can slide within a closed channel made of a material having a low coefficient of friction, for example defined by a sheath.

A gravity actuated torque generator for generating torque to run a generator by continually adding weights to the apparatus. The gravity actuated torque generator includes a support assembly, a drive assembly being supported by the support assembly, and a weight assembly being engagable to the drive assembly while moving downwardly due to gravitational forces for generating torque.

A control device for blinds includes a transmission unit, a scrolling unit and a tilting unit, the transmission unit includes a case in which a coil spring and a gear unit are received. The coil spring is connected between the gear unit and the case. The scrolling unit includes two scrolling rods which are rotated with a transmission rod. Each scrolling rod has a lift cord wrapped thereon and extending through slats of the blinds. The tilting unit includes two tilt members connected to two respective end sections of the two scrolling rods. Two tilt cords have two respective positioning members which are clamped in two clamp grooves of the two tilt members and the tilt cords extend through the slats. The gears in the gear unit can be adjusted so as to cooperate with slats of different weights.

Disclosed is an apparatus and method for generating energy through oscillatory motion requiring little input. Oscillatory motion is generated using a substantially circular trough containing a liquid, inflatable bags positioned below the trough and a movable weight. The trough is pivotally connected to a central point about which it oscillates. Sustained oscillatory motion is encouraged by inflating and deflating the bags in coordination with the movable weight within the trough and a biased member upon which the bags reside. The oscillatory motion may be captured and transferred to rotary motion which may be used to drive a generator.

A vehicle passive entry side door latch release system engageable with a release cable connected a door latch includes a moveable linkage assembly engageable with the cable, and a motor including an output shaft engaged with a tensioning gear for driving a ratcheting gearwheel rotatably affixed to a coil spring, with the gearwheel including external teeth engageable with a rack affixed to the linkage to move the cable to unlatch the door latch. A pivotable ratcheting pawl may be engageable with the gearwheel to allow or prevent rotation of the gearwheel. Operation of the motor may drive the gear to drive the gearwheel in a rotary direction to energize the spring, and disengagement of the pawl from the gearwheel may allow stored energy in the spring to drive the gearwheel in an opposite rotary direction to thereby drive the rack to move the cable to unlatch the door latch.

A fluid dispensing system provides a sprayer. The system has a container with liquid fluid, such as used in lawn and garden weed control and fertilization. The sprayer has a handle containing a spring engine and a pump for liquid from the container. The spring engine has a flat spring having a spring band extending from two coils wound on two shafts. One of the coils is manually wound by a crank connected to a shaft on which the coil is connected. The other shaft is connected to the pump by a rotary cam driver. Liquid is sucked by the pump into a pump chamber during part of a cycle of rotation of the other shaft when the coils are unwound and the liquid is pumped out of the chamber during the other part of the cycle of rotation to a sprayer head on the sprayer handle.

An actuation mechanism for a tarping system includes a double coil spring mountable on a pivot shaft of the mechanism. A bushing is mounted on the pivot shaft and within the double coil spring. The bushing includes an eccentric external periphery that limits the deflection of the spring, particularly at the transition points between the center portion and each of the coil portions of the spring. As the spring winds or coils, the coil portions progressively contact the eccentric periphery of the bushing to not only limit further movement of the coil portions, but also to provide support for those portions under load.

The invention provides an operational mechanism for a movable body in which, after a movable body is in an opened state, the movable body can return to a closed position, including a movable body rotatably attached to a support and rotatable between an engaged position, a closed position, and an open position; a rotating member rotatably attached to the support, that rotates due to movement of the movable body to the engaged position; a biasing member, one end of which is attached to the movable body, and the other end of which is attached to the rotating member; and an operation member, which rotates the rotating member, changes the biasing position of the biasing member with respect to the center of rotation of the movable body, and generates in the biasing member a rotational force that moves the movable body to the closed position or the open position.

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.

A shopping cart is equipped with an electrical/electronic component(s), such as a shopping assistant, that is electrically powered by a rechargeable power supply. A system is provided for continuously recharging the power supply as the shopping cart is propelled by the customer. In one embodiment, the wheels of the shopping cart are linked to a potential energy storage component, such as a coil spring. The spring is wound with each movement of the shopping cart, regardless of the distance that the cart travels. When the coil spring has been wound to a pre-determined torque, the spring is released to drive an input to an electrical generator. Once the potential energy in the spring has been dissipated the winding cycle begins again.

An inexpensive apparatus for powering a toy plane including a rubber band motor which is connectable to the plane's propeller and to a winding mechanism, including a gear mechanism which is activated by a handle. As the handle is repeatedly squeezed and released by the user, the motor is wound up. An anti-reversing ratchet is coupled with the motor to prevent unwinding until the user wishes to launch the plane.

An actuator assembly having a housing, at least one rotating gear member including a cam, and an actuator device operably connected to the rotating gear member, operably contained in the housing, for rotating the gear member. Also included is a bearing member operably associated with the cam such that when the actuator device is actuated for rotation of the gear member, the bearing member moves on the cam for providing relative motion between the bearing member and the rotating gear member. The actuator device is selected from a torque generating device or a device having linear movement.

A linear recliner assembly in use with a seat having a seat back pivotally engaged relative to a seat bottom. A housing exhibits a communicating interior between a first and second ends. A drive rod is supported in linearly displaceable fashion from the first end and is secured to the seat bottom. The second end pivotally engages the seatback spaced from its pivot point. A rotatable gear located at a fixed lineal position within the housing receives the drive rod in threadably inter-engaged fashion. A trigger mechanism pivotally secured to the housing exhibits a downwardly biased detent communicating through an opening in the housing to seat between succeeding teeth of the gear. A spring supported within the housing contacts the drive rod. Upon release of the detent, a reclining force applied to the seatback results in displacement of the housing against the drive rod to bias the spring. The spring influencing the drive rod in a reverse direction such that, upon release of said detent when the seatback is in the reclined position, the spring influences the seatback to reverse pivot to a returned upright position.

A drive mechanism for a device with two operating parts, which are connected so as to be pivotally displaceable relative to each other between a first position and a second position about a common axis of rotation. The drive mechanism has a driving mechanism such that a movement from the first position to the second position can be initiated initially by a slight movement and the additional movement is then effected automatically through spring force (F) until the second position has been reached. The movement out of the first position into the second position is possible in either a clockwise and counterclockwise movement. The driving mechanism comprises a driven part, one operating part and two drives that are in the form of a force storing device The force storing devices interact with the driven part in opposing directions in such a manner that only the one for storing device is in driving connection with the driven part while the other force storing device is retained in its starting position.

In an electricity generating device by applying vehicle weight, a rolling vehicle wheel is weighting down on a pressure receiver to actuate a driving mechanism having a restoring function. It is then able to provide a unidirectional rotating torque to drive a generating device to produce electrical power. The mechanical power transmission is performed by a transmission gear unit composed of a driving wheel and a follower wheel interconnected each other with a transmission means therebetween. When the vehicle weight is applied to the driving mechanism by pressing the vehicle wheel on the pressure receiver, the driving mechanism is forced to downwardly urge a ratchet wheel and a driving wheel to rotate that in turn causes the rotation of the follower wheel through the transmission means thereby driving the generating device to operate to produce electricity. The driving mechanism can recover its initial state with the aid of a balancing weight as soon as it has been liberate from the exerted pressure of the vehicle wheel. The device is to be installed flush with the road surface to work.

A mechanical energy storage system includes a containment vessel, a drive shaft operatively connected to a generator/motor and supported for rotation in the containment vessel. A support structure is attached to the drive shaft and configured for radial extension from a rest position proximate the drive shaft. A resilient member having a mass and extending circumferentially around the drive shaft is connected to free ends of the support structure and configured to store elastic energy when the support structure extends radially from its rest position. Upon rotation of the drive shaft, the resilient member stores both elastic and rotational energy commensurate with its mass and elastic properties.

An actuator for a wheel guiding element of motor vehicle wheel suspensions, with a first, preferably electrically driven actuating drive which selectively changes the length of the wheel guiding element, in the actuator there being a compensation spring which counteracts the compressive forces acting on the wheel guiding element. According to the invention, the pretensioning force of the compensation spring can be changed by means of a second, preferably electrically driven actuating drive.

A device for generating rotational movement which includes an output shaft supported for rotational movement and at least two one-way clutch mechanisms attached to the output shaft. An inflatable piston (“infton”) assembly is associated with each one-way clutch mechanism and includes a weighted member, an inflatable bladder associated with the weighted member, at least one inlet valve associated with an interior of the inflatable bladder, at least one outlet valve associated with the interior of the inflatable bladder, and a chain associated with the weighted member and extending over and drivingly engaging the respective one-way clutch mechanism. A source of filling fluid supplies each inlet valve. The filling fluid has a density less than that of a buoyancy fluid surrounding the infton assembly. A control system is configured to control the inlet and outlet valves to facilitate filling and discharging of the inflatable bladders.

In accordance with embodiments, there are provided systems and method for In accordance with embodiments, there are provided systems and method for generating mechanical movement that includes a resilient member having an original shape. A bulwark is connected to the resilient member. A system is provided to selectively apply a torsional force to the resilient member using capillary forces to rotate the resilient member with respect to the bulwark. This places the resilient member in a deformed shape. The system also selectively terminates the capillary forces allowing the resilient member to return to the original shape. These and other embodiments are described more fully below.

A spring motor and drag brake for use in coverings for architectural openings.

A method for ascertaining a rotational speed parameter for determining a setpoint torque for driving a drivetrain. The drivetrain comprises a first and at least one second drive assembly for driving a hybrid vehicle. The first drive assembly can be coupled to the drivetrain by means of a clutch. The second drive assembly is mechanically coupled to the drivetrain. When the hybrid vehicle is being driven by means of at least the first drive assembly, the rotational speed parameter corresponds to the value of a shaft rotational speed. When the hybrid vehicle is being driven only by means of the second drive assembly, the rotational speed parameter corresponds to the value of a determined rotational speed.

A winding tool for tightening a torsion spring for a sectional overhead door. The winding tool features two half hub assembles that wrap around an overhead door shaft, wherein a translational sprocket is disposed on the hub assemblies. The hub assemblies connect to the winding cone of a torsion spring via fingers that engage the hub assemblies. A winding box is removably attached to the hub assemblies. The winding box features a worm gear that engages the translational sprocket. A handle bar can be rotated with a drill to cause rotation of the worm gear. Rotation of the worm gear causes rotation of the translational sprocket and ultimate winding of the torsion spring.

A tensioner as well as a method for fitting a safety line cable on the tensioner. The tensioner designed for the safety of personnel attached to the cable while working under dangerous conditions. The tensioner has a fixing element configured to couple to an external element such as a wall and has two sections capable of separating and absorbing energy as a result of a fall of a worker while attached to the safety line cable. A section of the cable passes through and is crimped in a sleeve of the tensioner while the cable is kept under tension.

A patient side-system includes a column with a rail and a counterbalance subsystem. The patient side-system may further include a braking subsystem. The counterbalance subsystem includes a spring assembly coupled at one end to the column with a spring member, and a housing movably coupled to the rail. The housing includes a drum to receive the spring member and a plurality of roller elements to guide a movement of the spring member winding or unwinding on the drum. If present, the braking subsystem includes a first pulley rotatably coupled to the column, a second pulley with a locking mechanism spaced apart from the first pulley and rotatably coupled to the column, and at least one brake cable wrapped around the first pulley and the second pulley with ends coupled to the housing. The locking mechanism can set a position of the housing along the column.

A linear recliner assembly in use with a seat having a seat back pivotally engaged relative to a seat bottom. A housing exhibits a communicating interior between a first and second ends. A drive rod is supported in linearly displaceable fashion from the first end and is secured to the seat bottom. The second end pivotally engages the seatback spaced from its pivot point. A rotatable gear located at a fixed lineal position within the housing receives the drive rod in threadably inter-engaged fashion. A trigger mechanism pivotally secured to the housing exhibits a downwardly biased detent communicating through an opening in the housing to seat between succeeding teeth of the gear. A spring supported within the housing contacts the drive rod. Upon release of the detent, a reclining force applied to the seatback results in displacement of the housing against the drive rod to bias the spring. The spring influencing the drive rod in a reverse direction such that, upon release of said detent when the seatback is in the reclined position, the spring influences the seatback to reverse pivot to a returned upright position.

The technology is directed to an energy storage and release system that stores energy and enables a repeatable and accurately timed release of energy. A shaft member supports a drive assembly, a locking assembly and a lever member there between. The lever member and locking assembly are attached to the shaft. The drive assembly rotates freely about the shaft and loads energy into a torsion spring in communication with the lever member. The torsion spring connects at one end to the drive assembly and at the other end to the lever member without contacting the shaft member. The locking assembly provides a triggered release mechanism for selective release of stored energy from the torsion spring that accordingly rotates the lever member. The system can automatically reload the torsion spring once a signal is received from any number of events including, when the rotating lever member contacts a stop member or limit sensor that signals the end of travel for the lever member in either rotational directions.

A method for operating a window cover utilizes an extendible window cover having a first rail, a second rail and a pair of lift cords. The first and second rails of the window cover are movable relative to each other. According to the method, at least one of the first rail and the second rail is moved in a first direction to cause the lift cords to unwind from the lift cord pulleys, thereby rotating a lift cord pulley shaft and a set of gears. Further, at least one of the first rail and the second rail is moved in a second direction to cause the lift cords to wind on the lift cord pulleys, with the lift cord pulley shaft rotating in an opposite direction.

Water heaters are described that are user-powered, such that external sources of power are unnecessary. The water heaters include a heating device and a generator coupled to a crank such that power is generated as the crank is rotated, which can be used to power the heating device.

An energy storing device is disclosed. In the energy storing device of the present invention, energy from an energy generating unit is stored in the form of spring torsion and then is output steadily. The energy storing device of the present invention includes a plurality of cog-wheels, a plurality of torsion magnitude limiting units, a plurality of single-directional input bearings, a plurality of energy storing units and a plurality of speed enhancing cog-wheels. Each of the energy storing units includes at least two end rotational disc portions, which are connected with each other co-axially. A leaf spring unit is provided between each pair of rotational disc portions and one end of the leaf spring unit is bent in an opposite direction. In addition, the energy storing units may be connected in series or in parallel to increase the efficiencies in energy storage and energy output.

A window cover system includes an extendible window cover with a pair of lift cords. A lift cord pulley shaft is coupled to a pair of spaced apart lift cord pulleys. A spring drive unit has a beveled gear system with a first gear that is spring biased to resist rotation of first gear in one direction of rotation, and a second gear meshed with the first gear. The lift cord pulley shaft extends through the second gear and is configured to rotate therewith.