Abstract: A shade positioning system which employs a wrap spring clutch system includes a shade operator, a shade roller, and an idle end bracket for supporting the shade roller when mounted. The shade operator includes a self-lubricating central stud around which a helical coil spring is wrapped, a manually operated pulley mounted on the wrap spring, and a support bushing to ensure positive engagement of the aforementioned elements. The central stud is composed of a plastic or metal, which allows the smooth rotation of the wrap spring around the stud. The tangs of the wrap spring project substantially radially outward from the spring central axis, and are shaped to accommodate for the coefficient of friction between the stud and the spring. A first preferred spring construction allows for decreased spring surface area to contact the stud. A second preferred spring construction allows for an increased spring surface area to contact the stud.

Abstract: A wrap spring clutch having a first component rotatable around a rotary axis, a second component rotatable around the rotary axis, and a wrap spring arrangement, which is held in a substantially rotation-proof manner on one of the two components relative thereto and is at connective rest or can be brought into connective rest on a circumferential surface of the other of the two components to establish a rotary connection between the first and second components. The wrap spring arrangement is at connective rest with a first spring section on a circumferential surface of the first component for torque transmission and is at connective rest with a second spring section on the circumferential surface of the other component.

Abstract: A gear mechanism containing a clutch assembly made of an outer member with an offset hub, a wrap spring, a pin wherein the rotation of the pin around the offset hub is less than one revolution. A protrusion on a stop at a fixed location is used to dislodge the wrap spring such that it is incapable of transferring torque to the pin. With the spring dislodged, the pin ceases rotation as the hub continues to rotate. Once the power source reverses the rotation, the spring engages the pin which causes the spring to tighten around the hub. The tightening of the spring causes the spring to transmit torque and consequently move the pin away from the stop. In applications where, in one direction, a rotation of less than one revolution is acceptable, the use of a fixed protrusion to dislodge the spring allows the full torque of the driving member to drive the mechanism in either rotational direction.

Abstract: An improved apparatus for transmitting a rotational power from a pulley to a drive shaft of a compressor is disclosed. A coil spring is mounted on the drive shaft to absorb a load applied to the drive shaft when power is transmitted. The coil spring is arranged to be deformed upon generation of the load. A structure that transmits the power to the coil spring is securely attached to the pulley and coupled to the coil spring with a predetermined interference.

Abstract: A combination clutch and brake uses a helically wound spring attached to a pulley at one edge and magnetically drawn to a rotor at a second edge. In a relaxed state, the spring presses against an outer field cup locking the pulley against that cup. In a torsion state caused by the magnetic attraction between the rotor and the spring, the spring decreases in diameter to compress a frictional wedge inward against the pulley and rotor causing them to turn as one.

Abstract: A wrap spring operating mechanism for use in a random start/stop clutch, brake, or combined clutch/brake assembly limits the rate of acceleration or deceleration of the second member relative to the first member when the assembly is engaged. The assembly includes a first member, a second member, and a helical spring wrapped about adjacent portions of the first and second members. An annular control collar is disposed circumferentially about portions of the first and second members. The wrap spring has a first end that is connected to the first member and a second end that is connected to the control collar. An annular armature is connected to the control collar for rotational movement therewith and for relative axial movement. An annular rotor is disposed circumferentially about and connected to the second member. An annular friction ring is disposed within a recess formed in the rotor. The friction ring is formed from a material having a relatively low coefficient of friction, preferably about 0.

Abstract: A magnetic flux path mechanism for a solenoid actuated device includes a stationary coil for generating lines of magnetic flux when energized, a stationary case enclosing the stationary coil on an outside perimeter of the coil, and a rotatable sleeve disposed on an inside perimeter of the stationary coil. A magnetic flux path is provided through the stationary case and rotatable sleeve about the stationary coil. In a preferred embodiment, a wrap spring is disposed on an output shaft of the solenoid actuated device and is normally engaged on its outside perimeter with the inside perimeter of the rotatable sleeve. The rotatable sleeve is continuously driven in a forward direction and, because of the self engaging wrap spring, drives the output shaft in the forward direction. The sleeve is of an iron composition as it forms part of the core of the solenoid for enabling the magnetic flux.

Abstract: A rotary impulse tool has a motor-driven drive shaft and an output shaft. The drive shaft is threadedly coupled to a flywheel sleeve, which is spring-biased forwardly and is splined to a rotatable race structure of a wrap spring clutch assembly, which includes a wrap spring disposed in clearance fit coaxially between cylindrical surfaces of the race structure, the wrap spring having a front end fixed to the output shaft and a rear end coupled to a first conical control member. A second conical control member is axially movable between engaged and disengaged positions relative to the first control member for, respectively, shifting the clutch assembly to an engaged condition for transmitting torque between the drive and output shafts and a disengaged condition for decoupling those shafts.

Abstract: A spring clutch includes a driving-side boss integrally formed with a driving gear and a driven-side boss having a feed roller fixed. The driving-side and driven-side bosses are arranged on a common axis so as to be opposed to each other. A coil spring is wound on the peripheral side of the driving-side boss and driven-side boss. The spring clutch further has a sleeve fitted over the coil spring while a driving-side coil end of the coil spring is engaged with the sleeve. As rotation of the coil spring and the sleeve is restricted by a projection formed on the peripheral surface of the sleeve, the coil spring is idly fitted on the driving-side boss so that the rotation of the driving-side boss is not transmitted to the driven-side boss while the reverse rotation of the driven-side boss is restricted.

Abstract: An electromagnetic spring clutch includes a stator, an excitation coil, an input-side rotating member, an output-side rotating member, a coil spring, and a rotor. A central hole is formed in the stator. The central hole has an inner circumferential surface formed by a plurality of magnetic pole segments that mesh each other alternately through a gap in circumferential and axial directions. The excitation coil is accommodated in the stator. The input- and output-side rotating members are made of a non-magnetic member and formed with fitting portions and coil tight-winding surfaces. The fitting portions respectively support the two open end portions of the central hole of the stator, and the coil tight-winding surfaces have end portions that oppose each other in the central hole. The coil spring is wound on the coil tight-winding surfaces of the two rotating members and has one end hooked by the input-side rotating member.

Abstract: An over-running clutch pulley in which a pulley sheave and hub cooperate to define a composite inner cylindrical surface. A coil spring engages the composite cylindrical surface. The spring is oriented to transfer torque from the pulley sheave to the pulley hub when the pulley sheave is driving the pulley hub. The spring allows slip to occur between the pulley hub and sheave when the sheave is decelerated relative to the hub.

Abstract: A bi-directional sprang clutch further including a ratchet and pawl so as to permit substantial torque to be transmitted to the shade roller only in one direction. In the other direction, the roller is nearly free to rotate so that the weight of the shade material depending from one side of the roller exerts a torque on the roller which prevents reverse rolling.

Abstract: An infinitely variable forward speed mechanical transmission uses asymmetric helical/spur gear trains mounted to rotate within a rotor assembly to reduce the torque output within the rotor assembly through inefficiency of the asymmetric gear trains. The rotor assembly includes integrated input and output hubs having adjacent radially flush outer control surfaces, with the output hub in mesh with the asymmetric helical/spur gear trains in mesh with an output shaft. A transmission speed control device connected to a control gear connected to a control tang of a wrap spring positioned about the control surfaces of the input and output hubs provides infinitely variable control of the relative rotation of the two hubs to selectively control the torque output of the transmission.

Abstract: A down shift mechanism for incorporation in a device such as an assembly tool includes a wrap spring which locks and releases a planetary gear speed reduction assembly to provide shifts between two drive ratios in response to torque throughput. The wrap spring is received upon a drive drum within a cylindrical housing. The ends of the wrap spring are engaged by a pair of relatively rotationally adjustable and fixable spring engaging lugs which adjust the preload of the wrap spring and thus the torque level at which the spring unwraps and lifts off the drive drum and thus the torque level at which the shift occurs. The wrap spring housing is coupled to the ring gear of the planetary gear assembly. When the torque applied to the wrap spring exceeds the preload, the spring unwraps, unlocking the ring gear and planetary gear assembly and downshifting to the speed reduction determined by the planetary gear assembly. An alternate embodiment of the downshift mechanism is also presented.

Abstract: A spring clutch assembly with reduced radial bearing forces is described. The clutch includes a shaft, at least first and second helically wound axially mounted springs for making frictional contact with the shaft, and engaging means corresponding to each of the first and second springs for selectively applying a tightening force to one end of each of the springs in order to prevent rotation with respect to the shaft. Each of the engaging means is radially and symmetrically disposed along the shaft for eliminating radial bearing force induced by the spring ends.

Abstract: A solenoid for controlling the engagement and disengagement of a wrap spring clutch includes an electromagnetic coil having a core member disposed adjacent one axial end thereof. An armature is provided within the electromagnetic coil for selective axial movement in response to the energization and deenergization of the electromagnetic coil. The armature is connected to an actuator for the wrap spring clutch such that movement of the armature controls the engagement and disengagement thereof. The core member and the armature are both formed from relatively soft, magnetically permeable materials. A flux breaker is disposed within the electromagnetic coil between one axial end of the armature and the core member. The flux breaker is formed from a relatively hard, non-magnetically permeable material, such as stainless steel. The flux breaker prevents the armature from contacting the core member when attracted thereto by energization of the electromagnetic coil.

Abstract: A wrap spring clutch, for use in a percussion device activated by a fluid having a lubricant therein, includes a plurality of grooves in at least one of the friction engagement surfaces of the wrap spring clutch, to transmit a portion of the lubricant away from the friction zone of the clutch, to enhance the friction performance of the clutch. The grooves can be parallel and separate, or a single, continuous spiral groove.

Abstract: A wrap spring clutch assembly is disclosed which is designed for use with a rotary element which is subjected to repeated intermittent rotary motion. The clutch assembly includes a first circular hub fixedly attached to the element for rotation therewith, a wrap spring mounted on the first hub and adapted to grip or release the hub depending on the direction of movement of a free tang of the wrap spring. A second, split hub acting as a resilient shock absorber is mounted on the rotary element and underlies a portion of the wrap spring so as to deflect inwardly when the wrap spring grips the first hub thereby permitting a small amount of additional rotation of the rotary element to provide a controlled deceleration of the rotary element, thereby absorbing the shock force of virtual instantaneous deceleration of the rotary element which otherwise occurs and tends to break the wrap spring at the juncture of the spring coils and the tang which is attached to the rotary element.

Abstract: A torque transmission device includes an input shaft, an output shaft, a helical spring, a fixing member, and a stopping member. The helical spring has an input portion frictionally connected to the input shaft and an output portion frictionally connected to the output shaft, and rotatable together with the input shaft and the output shaft to transmit the torque of the input shaft to the output shaft. The stopping member is engageable with an input end portion of the spring at a predetermined engaging position and adapted for stopping the output shaft at a predetermined rotational position. The fixing member is used to fix an output end portion of the spring on the output shaft at such a position as to assure a predetermined phase relationship between the engaging position and the rotational position.

Abstract: A fixed torque spring clutch has first and second rotors. The torque of the first rotor is transmitted to the second rotor via a coil spring. The second rotor is coaxial with the first rotor. A shaft section is provided on one of the rotors. A plurality of catch sections are provided on the other rotor. The coil spring is mounted over the shaft section. The two ends of the coil spring are caught by the catch sections in a clamping state of the clutch. The coil spring has a first clamping section for clamping the shaft section with a predetermined clamping force when the coil spring is mounted over the shaft section, and a second clamping section having a clearance with respect to the corresponding part of the shaft section when the coil spring is mounted thereon.

Abstract: An electromagnetic wrap spring clutch having a field assembly made from a single L-shaped bracket is disclosed. This L-shaped bracket design improves upon previously known round body or bracket and yoke designs.

Abstract: A fail safe valve actuator is disclosed that is powered by an electric motor. A valve stem with a helical groove is moved in one direction by a ball nut rotated by the electric motor to move a valve member to its operating position. The valve member is held in operating position by a solenoid. When power fails, a spring moves the valve stem in the other direction to move the valve member to its fail safe position. A torque limiting device protects the electric motor from the high torque created when the valve stem abruptly stops moving when the valve member reaches its operating position. A centrifugal brake absorbs a portion of the energy released when the power fails and the valve stem is moved rapidly to its fail safe position by the spring.

Abstract: An overrunning clutch is provided with increased torque transmitting capacity by utilizing a relatively large diameter spring wire whose end turns have their radial peripheries ground down to weaken the end turns proximate to the free end of the spring. Preferably the end turns proximate to the free end of the coil spring are tapered radially inwardly to lift the spring coil turns remote from the free end off the shaft of the overrunning clutch. The end of the coil spring fixed to the bushing may be formed as a hook having a portion extending radially through a slot within the bushing and an integral bent back circumferential portion nested in an annular groove within the outer periphery of the bushing intersecting the radial slot. A double helical coil spring having parallel, adjacent turns within separate helical grooves within the inner periphery of the bushing has a loop connecting the turns opposite their free ends mounted within a transverse channel connecting the pair of helical grooves.

Abstract: According to the invention, there is provided a damper for a flapdoor that does not show any damping effect when its movable shaft of the damper is rotated with the door in one sense whereas it effectively damps the rotary movement of the flapdoor when the movable shaft is rotated with the door in the other sense, wherein a one-way clutch for engaging or disengaging the movable shaft with a movable member depending on the sense of rotation of the movable shaft to cause a viscous shearing drag in the viscous fluid contained in the damper and a power source constitute so many integral parts of a coil spring. A damper for a flapdoor having such an arrangement can have a simplified configuration as compared with a damper provided with a separate coil spring as power source and a separate one-way clutch and therefore can be realized with reduced dimensions.

Abstract: The assembly tool comprising an electrically operated clutch assembly and achieves rapid termination of energy throughput to provide accurate torque delivery for fastener tightening and similar applications. The clutch assembly includes a pair of equal diameter, axially aligned input and output hubs having a wrap-spring disposed thereabout. One end of the wrap-spring is coupled to the input hub and the other is coupled to a control annulus disposed concentrically and freely rotatably about the output hub. An electromagnet also concentrically disposed about the output hub is activated to couple the control annulus to the output hub. A resulting drag on the wrap-spring tightens it about the output hub and power is transmitted. Deactivation of the electromagnet provides rapid release of the wrap-spring and termination of power throughput. A one way (overrunning) clutch couples the hubs when power is applied in the opposite direction to, for example, facilitate removal of fasteners.

Abstract: A self-braking electromagnetic wrap spring clutch having a wrap spring control ring and a brake control armature plate at separate locations within a common magnetic circuit.

Abstract: An electromagnetically actuated spring clutch permits transference of rotational motion from an input hub to a coaxially-disposed rotatable shaft. A selectively actuable source of magnetic flux, such as an electromagnetic coil, is disposed around at least a portion of the shaft with a space therebetween. A housing, at least a portion of which is conductive of magnetic flux, substantially envelops the outer surface of the source. A shaft flange, also conductive of magnetic flux, is disposed around a portion of the shaft. A helical spring, having a first end attached to the input hub and a free end disposed adjacent the shaft flange, is loosely engageably coiled around the shaft, in the space between the shaft and the source. magnetic flux flowing through the shaft flange attracts the free end of the helical spring and thereby causes the helical spring to contact about and engage the shaft.

Abstract: An electromagnetic spring clutch has an armature (40) which can be moved to and from in the axial direction thereof and cannot be rotated on the axis, and which is biased by a spring (46), and a coil spring (36) which covers over outer faces of a master driving axle (30) and a slave driving axle (34) and which is capable of being wound tightly in the rotational direction of the master driving axle (30). When an electromagnetic coil (20) is not energized, an engagement section (44a) at the end of the armature (40) and a hook (38) of the coil spring (36) are engaged to expand the inner diameter of the coil spring (36) and disconnect the master driving axle (30) and the slave driving axle (34).

Abstract: The fixed torque spring clutch of the present invention has a first rotor and a second rotor. The rotation of one rotor can be transmitted to the other rotor by a coil spring. The first rotor has a shaft section, the coil spring has a clamping section winding round the shaft section, and a non-clamping section arranged in spaced circumferential relation with the outer face of the shaft section. The second rotor has a holding piece and releasing piece arranged in spaced circumferential relation thereon. The holding piece engages the non-clamping section of the coil spring to increase the torque it applies to the shaft section. The releasing piece then engages the clamping section of the coil spring to decrease the torque it applies to the shaft section. The cooperating action of the holding piece and releasing piece on, respectively, the non-clamping and clamping sections of the coil spring results in maintenance of a prescribed fixed torque on the shaft section.

Abstract: An overrunning clutch is provided with increased torque transmitting capacity by utilizing a relatively large diameter spring wire whose end turns have their radial peripheries ground down to weaken the end turns proximate to the free end of the spring. Preferably the end turns proximate to the free end of the coil spring are tapered radially inwardly to lift the spring coil turns remote from the free end off the shaft of the overrunning clutch. The end of the coil spring fixed to the bushing may be formed as a hook having a portion extending radially through a slot within the bushing and an integral bent back circumferential portion nested in a annular groove within the outer periphery of the bushing intersecting the radial slot. A double helical coil spring having parallel, adjacent turns within separate helical grooves within the inner periphery of the bushing has a loop connecting the turns opposite their free ends mounted within a transverse channel connecting the pair of helical grooves.

Abstract: A spring clutch for limiting lost motion during release is provided. The spring clutch includes a shaft, a helically wound coaxially mounted spring for making frictional contact with the shaft, and means, such as a tang element, for selectively applying a loosing force to at least one end of the spring for rotation thereof with respect to the shaft. The inventive spring clutch further includes means for urging the spring toward the shaft when the spring is rotatably loosened. As a result, radial movement of the spring away from the shaft is substantially prevented. The urging means may be retained by a housing coaxially mounted about the shaft and may be chosen from a boss or an auxiliary spring. Preferably, the urging means is located at about 90 degrees along the outer radial surface of the shaft from the end of the spring at which the tang element is located.

Abstract: An electromagnetically controlled spring clutch mechanism including a rotating output member, a rotating input member, an armature assembly, an electromagnetic coil assembly and a coil spring. The coil spring is fitted astride both the output boss of the rotating output member and the input boss of the rotating input member. One end of the coil spring is anchored at the rotating input member, and the other is anchored to the armature assembly. The rotor of the rotating output member, the armature assembly, and the electromagnetic coil assembly are arranged in this sequence in the axial direction. The electromagnetic coil of the electromagnetic coil assembly is positioned radially outwardly of the coil spring. The electromagnetic coil assembly includes a casing, and this casing covers the rotor of the rotating output member, the armature assembly, the electromagnetic coil of the electromagnetic coil assembly and the coil spring.

Abstract: An electromagnetically controlled spring clutch mechanism includes a rotating output member, a rotating input member, a coil spring fitted astride the outer peripheral portions of these two members, an armature assembly disposed on the outer peripheral portion of the coil spring, and an electromagnetic coil assembly. When the electromagnetic coil is deenergized, the coil spring contracts in a tightening direction so that the output and input members are drivingly coupled together. When the electromagnetic coil is energized, rotation of the armature assembly is hampered, and the coil spring expands so that the output and input members are decoupled.

Abstract: Difficulties in positively engaging and disengaging helical spring clutch mechanisms are avoided in a construction including a driven shaft (10) with a gear (18) rotatably mounted on the shaft (10). A helical spring (40) is disposed about part (24) of the gear (18) and the driving shaft (12) and a reaction collar (28) is located adjacent to the spring (40) and is splined to the driving shaft (12). A friction collar (52) is engagable with the helical spring (28) and is carried by the driving shaft (10). Ball actuators (62, 64) are provided for selectively engaging the friction collar (52) with the helical spring (40) thereby causing the spring (40) to engage the reaction collar (28) and rotate with the driving shaft (12) to drive the gear (18).

Abstract: The present invention relates to an electromagnetic spring clutch. A conventional field core is formed in a bottomed cylindrical shape, so manufacturing such a field core is troublesome and uneconomical. When a through-hole through which shafts are inserted is provided in one or both of vertical walls of a U-shaped plate, a field core is provided simply and inexpensively.

Abstract: A clutch is provided which comprises a first rotatable member, a second rotatable member provided for rotational movement relative to the first rotatable member, a coil spring wound around the first and second rotatable members, and a one-way brake. Rotation of the second rotatable member in at least one direction causes the coil spring to contract so as to fasten together the first and the second rotatable members to rotate synchronously. The one-way brake is adapted for restricting the coil spring from rotating in the winding direction and allowing it to rotate in the release direction so as to allow independent rotation of the first and second rotatable members. Therefore, power can be transmitted to the first rotatable member from the second rotatable member but not in the other direction.

Abstract: A shaft-locking device which locks rotation of a movable shaft by a clamping force of a coil spring closely surrounding a fixed shaft and a movable shaft. Both sides of the coil spring are inserted surrounding the fixed shaft and a central portion of the coil spring surrounds the movable shaft. In case of rotation of the movable shaft on both sides, the locking torque is applied. Further, the closed state of the coil spring to the movable shaft is maintained uniformly without any relation to operation by separating the end portions of the coil spring at the movable shaft side of the coil spring from an outer circumference of the movable shaft so that a constant locking torque may be always obtained.

Abstract: A revolving door includes an elongated pivot column having a plurality of integrally formed first grooves extending longitudinally therealong at equidistantly spaced intervals therearound. A plurality of barrier members are provided. At least one of the members is associated with each first groove and arranged to extend radially outward of the groove. A locking device is concealably contained and interposed between the side wall of each first groove and a terminal end of each barrier member mountingly associated with the groove for retaining the barrier member in the groove. The locking member includes a second groove which extends longitudinally along the side wall of each first groove and a rigid locking bar extending into the second groove. The locking bar has a round side and a flat side and is selectively rotatable to wedging engage a wall of the second groove and the terminal end of each barrier member.

Abstract: Bi-direction spring clutch apparatus for a reducing worm gear drive is disclosed. The bi-directional spring clutch apparatus includes a worm gear drive comprised of a worm and an output shaft rotatably mounted in a housing. A worm gear is rotatably mounted coaxially about the output shaft so that its teeth mesh with the threads of the worm. The worm gear includes two coaxial extensions which are also rotatably mounted coaxially about the output shaft but which are rotatably fixed relative to the worm gear. Located adjacent to each of the coaxial extensions of the worm gear are two torque transfer bushings. These are of the same outside diameter as the coaxial extensions, but are rotatably fixed relative to the output shaft. Stretched over each of the torque transfer bushing/coaxial extension pairs is a wound spring, each of the same hand of winding, and each having sufficient revolutions to result in self-locking of the torque transfer bushing/coaxial extension pairs.

Abstract: Braking of independently-movable pivotable members is carried out by independent one-way clutch mechanisms which provide minimal braking force to the pivotable members in the vicinity of the limit points of their pivotable movement, and provide optimal braking force in a middle range of pivotable movement. The braking mechanism provided may operate on one or both of the pivotable members at the same time, each of the independent clutch mechanisms providing suitable braking force to compensate for the mass of the respective pivotable members.

Abstract: A spring clutch where an input shaft and output shaft are connected and disconnected with each other through a coil spring. The coil spring is secured at one end to the output shaft and is freely disposed over the input shaft at its other end. A centrifugally responsive pawl is mounted to engage the coil spring at the end disposed about the input shaft when said input shaft is rotated at or above a predetermined speed to cause said coil to be wound and tightened about the coil spring, thereby connecting the input and output shaft.

Abstract: A cylindrical bushing member includes at least one groove of a depth and width to fully accommodate a coil spring within the inner periphery of the bushing with the spring, when relaxed having an inner diameter slightly larger than the diameter of a shaft member projecting axially therethrough. The coil spring is fixed relative to the bushing so as to be non-rotatable relative thereto. The coil spring has at least one end in contact with the periphery of the shaft for frictional engagement therewith such that relative rotation of the bushing and the shaft in one direction causes multiple turns of the coil spring to engage the periphery of the shaft and to snub the spring and to cause a driving member to rotate a driven member as fast as that of the driving member, but permit the driven member to rotate faster and free-wheel to overrun the driving member.

Abstract: A torque responsive five-stage automatic shifting hub utilizes inner wrapped spring clutches to rotate a plurality of co-axial cylinders except for the cylinder at one end of the axis rotated by a sprocket. Gearing is interposed between the cylinders to rotate them at progressively different rpm. The wheel hub is rotated by outer wrapped springs, one over each cylinder, having one end secured to the hub and the other end floating. The outer wrapped springs automatically wrap on a cylinder rotating faster than the hub and automatically release a cylinder rotating slower than the hub. The inner wrapped spring clutches are actuated by compression springs between the cylinders which expand to actuate the associated clutch and compress to deactivate the clutch. The compression springs are of progressively different strengths along the axis of the cylinders.

Abstract: An electromagnetically controlled spring clutch mechanism comprising a first boss member rotatable as a unit with an input rotating element, a second boss member rotatable as a unit with an output rotating element, a coil spring fitted over and across the first and second boss members, a rotation control member for hampering contraction of the coil spring, a movable member, a magnet for biasing the movable member magnetically toward the rotation control member, and an electromagnet for magnetically attracting the movable member away from the rotation control member. When the electromagnet is energized, the movable member moves away from the rotation control member to permit contraction of the coil spring member, and the contraction of the coil spring effects a driving connection between the first and second boss members.

Abstract: In order to simplify the structure of the armature of an electromagnetic spring clutch and to lower the raw material cost, the armature is cylindrical and the field core is composed of a core section with a U-shaped bracket section having open sides and an open end and a yoke section fixed to the open end of the bracket section and having a through-hole in its middle in which the armature is inserted.

Abstract: A drive mechanism rotates a shaft of a station of a reproduction apparatus about an axis. The drive mechanism is supported by a mechanism plate in the apparatus, and the station is movable in a direction substantially parallel to the axis to engage the shaft with the drive mechanism and to disengage the shaft from the drive mechanism. Power from a source can be applied to the drive mechanism when the station shaft is disengaged from the mechanism, when the shaft is engaged with the mechanism but the station is not being operated, and when the station is being operated. The improved drive mechanism is particularly useful for one or more development stations of a reproduction apparatus such as a copier/duplicator, printer or the like.

Abstract: An electromagnetically controlled spring clutch mechanism for transmitting the rotating forces of an input rotating element adapted to rotate in a predetermined direction and in a direction opposite thereto to an output rotating element. According to one aspect, a first spring clutch mechanism and a second spring clutch mechanism are interposed between the input rotating element and the output rotating element, and the rotating force of the input rotating element in the predetermined direction is transmitted to the output rotating element by the contraction of a coil spring in the first spring clutch mechanism and the rotating force of the input rotating element in the opposite direction is transmitted to the output rotating element by the contraction of a coil spring in the second spring clutch mechanism.

Abstract: A spring clutch includes a driving hub attached to a drive shaft, a driven hub to which a mass to be rotated is attached, and first and second helical clutch springs which are engageable to interconnect the driving hub and the driven hub, the first helical clutch spring including a first portion of smaller diameter which is in preloaded contact with the driven hub and a second portion of larger diameter which has a radially outwardly-extending end, and the second helical clutch spring being in preloaded contact with the driving hub and including a radially outwardly-extending end. A rotatable clutch sleeve is connected to the end of the first helical clutch spring and is movable by a pivot lever to interconnect the end of the first helical clutch spring with the end of the second helical clutch spring so that rotation of the second helical clutch spring will cause rotation of the first helical clutch spring and thus the driven hub.

Abstract: An electromagnetically controlled spring clutch mechanism comprising an output rotating element, an input rotating element, a first boss member rotating as a unit with the input rotating element, a second boss member rotating as a unit with the output rotating element, a coil spring means fitted over and across the first and second boss members, a rotation control member for hampering the contraction of the coil spring, a movably mounted armature, a biasing device for biasing the armature toward the rotation control member, and an electromagnetic device for magnetically attracting the armature. When the electromagnetic device is deenergized, the armature acts on the rotation control member by the action of the biasing device whereby the contraction of the coil spring is hampered. When the electromagnetic device is energized, the armature is moved away from the rotation control member by the magnetic attracting force of the electromagnetic device whereby the coil spring is contracted.

Abstract: An adjustable torque limiting assembly includes a first wrap spring mechanism which provides a readily adjustable torque transmission limit and a second coaxially disposed wrap spring mechanism which provides a mechanical signal that the torque limit has been reached. This signal may be utilized to terminate an energy supply to a prime mover associated with the torque limiting assembly. The first wrap spring mechanism generally includes a wrap spring in which the spring moment and thus the slip or overrunning torque threshold may be readily adjusted. The second wrap spring assembly likewise includes a wrap spring which is activated only subsequent to slip of the first wrap spring and enlarges to engage a concentrically disposed control sleeve. The control sleeve then rotates and activates an associated shut-off mechanism.