Abstract: An automatically positionable joint for a modular tooling assembly includes a first joint member; a second joint member that is rotatably connected to the first joint member; a motor for causing rotation of the first joint member with respect to the second joint member; and a first clutch that is movable between an engaged position in which the first clutch restrains rotation of the first joint member with respect to the second joint member and a disengaged position in which the first clutch permits rotation of the first joint member with respect to the second joint member.

Abstract: An actuator with a motor produces a motive force to control a valve. The actuator includes a driving portion coupled to the motor to receive the motive force from the motor. Additionally, the actuator includes a driven portion coupled to the driving portion, the driven portion being coupled to a valve stem to drive movement of the valve between at least one of an open position and a closed position. The actuator includes a clutch positioned between the driving portion and the driven portion, the clutch being a one-way clutch to transmit motive force from the driving portion to the driven portion and block transmission of the motive force from the driven portion to the driving portion. Additionally, the actuator includes a brake arranged proximate the clutch to stop transmission of the motive force between the driving portion and the driven portion.

Abstract: A conveying and separating method and a device for separating sheet-shaped objects, for example preliminary chewing-gum products or intermediate chewing-gum products in the form of chewing-gum sheets, into strip-shaped or slab-shaped object sub-units. The conveying and separating method and device for separating sheet-shaped objects preferably separates sub-units one after another from each of the sheet-shaped objects at at least one weakened region on each of the sheet-shaped objects by a conveying and separating device that preferably has a revolving conveyor belt with suction elements that can be activated and deactivated. The suction elements pick up, hold, and convey the sheet-shaped object when the suction element is activated and release the sub-units when the suction element is deactivated.

Abstract: When an abutting member is in contact with a driving force transmission member that engages with a driving member, a biasing member biases the driving force transmission member in a direction where the driving force transmission member is disengaged from the driving member.

Abstract: A wrap spring clutch system includes one or more wrap spring clutch assemblies each having a latching actuator assembly. The latching actuator assembly includes an armature plunger movably coupled with a solenoid coil, and in a powered solenoid coil state the solenoid coil moves the armature plunger between deployed and retracted configurations. A latching magnet latches the armature plunger in one of the deployed or retracted configuration in an unpowered solenoid coil state. A latching spring latches the armature plunger in the other of the deployed or retracted configuration in an unpowered solenoid coil state. The wrap spring clutches include a rotatable input hub and a rotatable output hub configured for rotation by the input hub. A helical spring is engaged with the output hub and selectively engaged in slipping and locking engagement with the input hub according to the deployed or retracted configuration of the armature plunger.

Abstract: Transmission device comprising a first rotary member mounted coaxially on a second rotary member. The first rotary member can rotate in one direction independently from the second rotary member, and in the opposite direction is constrained to the second rotary member in order to rotate solidly therewith. The device can assume a first and a second condition of use, wherein the first rotary member rotates in the two directions independently from the second rotary member, and a third condition of use wherein clamping means, integrally associated with the first rotary member, move from a position of non-interference to a constraint position wherein they constrain the second rotary member in order to make the first rotary member and the second rotary member rotationally solid.

Abstract: A driving force transmitting clutch device includes a main shaft; a first rotor rotatable around the main shaft; a second rotor rotatable around the main shaft; an inner sleeve member attached to the second rotor for engaging the first rotor, and being movable in an axial direction of the main shaft; an outer sleeve member for receiving the inner sleeve member therein; and a coil spring for urging the inner sleeve member in a direction that the inner sleeve member engages the first rotor and the outer sleeve. When a movement of the outer sleeve is stopped, the outer sleeve moves the inner sleeve for releasing the inner sleeve from the first rotor and for releasing the inner sleeve from the outer sleeve.

Abstract: A method and a device are provided for achieving a step-by-step feeding, based on a rotary shaft which optionally can be made to execute one or more well-defined, whole rotation turns. The step-by-step feeding is achieved by mechanical connection between a driver joined to an output shaft and the inner periphery of a drive drum directly driven by a drive motor and arranged concentrically relative to both the driving and the driven shaft. The system is based upon the driver being adjustable between a first driving position and a second locked position.

Abstract: A torque-limiting accessory drive assembly comprising a pulley to transfer torque to an accessory drive system, a torque limiting device adapted to limit the maximum amount of transferred torque, and a one-way clutch assembly adapted to both selectively transfer torque and selectively interrupt torque transfer at predetermined times to the vehicle accessory drive.

Abstract: A torque-limiting accessory drive assembly comprising a pulley to transfer torque to an accessory drive system, a torque limiting device adapted to limit the maximum amount of transferred torque, and a one-way clutch assembly adapted to both selectively transfer torque and selectively interrupt torque transfer at predetermined times to the vehicle accessory drive.

Abstract: The dog clutch for a square baler is normally retained in a disengaged position as a continuously driven sprocket rotates around it during baling operations. When a retainer for the dog is released, the dog is released by the retainer and flips out to an engaged position so as to be driven through one knotter revolution by a driving lug on the rotating sprocket, whereupon it is reset by the retainer into its disengaged position. An external lobe on the rotating sprocket blocks releasing movement of the retainer if the driving lug of the sprocket is in the immediate vicinity of the dog, which could otherwise cause an insecure engagement of the lug with the dog. The dog-engaging seat on the retainer is spring-loaded to provide yieldable relief in the event binding starts to occur between the retainer and the dog.

Abstract: A device for actuating the clutch of a twine wrap device in a big square baler for harvested crops has a pawl attached to the clutch, a shift lever pivotable into the orbit of the pawl, a control device for the shift lever, and an electric motor which is drive-connected with the control device for the shift lever. The electric motor may be connected via an electric circuit with a device for determining the bale length.

Abstract: The dog clutch for a square baler is normally retained in a disengaged position as a continuously driven sprocket rotates around it during baling operations. When a retainer for the dog is released, the dog is released by the retainer and flips out to an engaged position so as to be driven through one knotter revolution by a driving lug on the rotating sprocket, whereupon it is reset by the retainer into its disengaged position. An external lobe on the rotating sprocket blocks releasing movement of the retainer if the driving lug of the sprocket is in the immediate vicinity of the dog, which could otherwise cause an insecure engagement of the lug with the dog. The dog-engaging seat on the retainer is spring-loaded to provide yieldable relief in the event binding starts to occur between the retainer and the dog.

Abstract: A drive mechanism for converting a reciprocating angular movement into one directional angular movement is disclosed for driving a shaft in a submersible cleaning device. In particular, a positive engagement clutch converts an alternating pivotal or angular motion of a shaft to a unidirectional circular motion of a driven gear. The shaft is affixed to a collar formation comprising pockets in which pawl elements are movably placed. The pawl elements engage teeth of a periphery ring that encloses the collar. The driven gear is affixed to the ring. The pawl elements operate in a dense medium such as the water of a pool in which the device is operating. The water imparts a high degree of inertia to the pawl elements and cause them to engage in the peripheral ring during the alternating motion of the shaft. Rotational movement of the driven gear to one direction is accomplished using a second pawl engaging a ratchet affixed to the periphery of the ring.

Abstract: A mechanical disconnect for the pedal operating rod of an attaching machine comprises a stationary trip slide having a downwardly inclined cam surface and a housing enclosing the trip slide and reciprocable thereon. The housing is connected to the clutch operating rod. The housing also includes a transverse trip spacer pin and a latch having a follower nose engaging the cam and a central L-shaped opening receiving the pin in the horizontal leg of the opening. A spring urges the latch toward the slide. When the pedal is depressed, the latch pulls down the housing so that the clutch activating pull down rod moves away from the clutch dog. Further downward movement of the pedal cams the latch away from the slide so that the spacer pin aligns with the vertical leg of the "L" permitting the housing to pop up and the pull down rod to engage a clutch dog.

Abstract: The invention relates to a switchable freewheeling ratchet unit 1a having a coupling sleeve 2 and a coupling hub 5 as well as radially resilient locking ratchets 13 and 38 per direction of rotation, which engage recesses 11 and 39 of the coupling hub 5 and which, depending on the direction of rotation, may be disengagable from the coupling hub 5 by a control ring 23 with control elements 21. The control elements 21 have first control faces 19, 19a and the locking ratchets 13 and 38 have second control faces 18, 18a facing the first control faces 19 and 19a for freewheeling purposes. The locking ratchets 13 or 38 not serving torque transmitting purposes are completely disengaged from the recesses 11 and 39, respectively, and are out of contact with the coupling hub.

Abstract: A coupling (1) which is disconnectable in the driving direction of rotation has a coupling hub (2) and a coupling sleeve (3) rotatably arranged thereon. The hub (2) and sleeve (3) are connected in the driving direction of rotation by at least one locking ratchet (9, 10) and locking ratchet recess (7, 8 and 13, 14) respectively of the coupling hub (2) and the coupling sleeve (3), a locking pin (19, 20) with its longitudinal side (23, 24) extending in a tangential transverse bore (21, 22) presses the locking ratchets (9, 10) out of the locking ratchet recess (13, 14) in the coupling sleeve (3) when a switching ratchet (36) causes the rotation of the switching ring (4) by means of locking pins (19, 20).

Abstract: In a clutch assembly, a driven member is driven by a driving member through an engaging or clutch member which is mounted on the driven member movably between a position to be engaged with the driving member and a position to be released from the driving member. The engaging or clutch member is thrust toward the engaged position by a first thrusting force. A releasing member is movable between an active position to abut at one end thereof against the engaging or clutch member and an inactive position to be apart from the engaging member, and is thrust toward the abutting end by a second thrusting force. When the releasing member abuts against the engaging member, the releasing member is first moved in the opposite direction to the second thrusting force direction by a driving force of the driving member to reach a stop position, and then the engaging member is moved in the direction to be disengaged from the driving member by the driving force of the driving member.

Abstract: Non-slipping clutch disposed between the drive and transport mechanism and between the drive and control cylinder for triggering printing in franking machines, including a shaft, a locking wheel being mounted on the shaft and engaged by the drive, internal gearing having an odd number of teeth formed on the locking wheel, a bushing being disposed on the shaft and connectible to the transport mechanism and control cylinder, a locking gear disposed on the bushing opposite the locking wheel, teeth disposed on part of the periphery of the locking gear, two pawls being disposed in the locking gear and extended into the locking wheel for engaging the internal gearing, a lever rotatably disposed on the bushing adjacent the locking gear, fingers being integral with the lever and engageable with the pawls, a torsion spring for rotating the lever and fingers to push the pawls into the internal gearing and couple the locking wheel and locking gear, and an electro-magnetically controlled latch for preventing the lever fr

Abstract: A mechanical clutch is described having a spring loaded clutch ring with a drive pin extending through a hole in a hub of a wheel and into a notch of a drive shaft. When pressure is exerted on the outer portion of the drive wheel, the spring is compressed and the drive pin is removed from the notch of the drive shaft. This allows the drive shaft to turn freely within the wheel and hub.

Abstract: A clutch mechanism having radially moving control pins which may be actuated to effect switching of the clutch into a freewheeling condition is formed to include catching members which engage the pins to lock them in position when the clutch mechanism switches to freewheeling operation. The catching members are formed with control cams which engage retaining pins to maintain the locked position of the control pins with rotation of a driving clutch member operating to allow the retaining pins to drop out of engagement with the control cam to enable release of the control pins when the clutch is switched back into the torque transmitting position.

Abstract: A wheelchair having a propulsion and speed change mechanism, the mechanism has a clutch with a cam clutch (21) and a cylindrical fly wheel (23) installed on a hub (24) of the shaft (25) of the main wheel of the chair. The clutch includes roller bearings (14), plate springs (22) and forward and backward regulating device (15). A matched union gear (20) is formed at the center of the cam clutch (21) and matched with a union gear (19) formed on a propulsion and speed change bar (12) so that the cam clutch (21) and the propulsion and speed change bar move as one body. The cam clutch (21) and the bar (12) are installed with a bearing (17) on the axle of the frame (13) of the wheelchair. A connecting rod (2) has one end connected to one of a plurality of holes (10) on the propulsion and speed change bar (12) with a fixing pin. The other end of the rod is connected to the hole (7) of the propulsion and speed change bar with a moveable pin (6).

Abstract: A driving coupling includes two pawls which are supported pivotally on an eccentric ring and which in a patternlike manner engage a longitudinal groove in the drive shaft. Each of two plates of a toggle-lever joint engages an arm extension of a respective pawl, the swivel axle of the toggle-lever joint being guided in a control groove of a swinging switching arm. When the pawls are engaged with a drive shaft groove, the toggle-lever joint is in an extended position which locks the pawls in position. For unlocking the pawls, the switching arm moves the toggle-lever joint into a catch opening between two guide rails. The pawls swing out and the drive shaft rotates without carrying along the pawls and the eccentric ring.

Abstract: A printer and in particular a printer adapted for use with a thermal print head is provided. The printer includes a power transmission which controls two clutches with a single electromagnetic driving unit. A clutch of a power transmission is initialized without the use of a detector by dividing the perimeter of the clutch into N equal rotating angles each equal rotating angle being further subdivided into a large rotating angle and a small rotating angle in combination with a preselected energization period for an electromagnetic control member which assures the initialization of the clutch in a desired position. The clutch is advanced one position by a second energization period of the electromagnetic control member. The carriage mover of the printer allows the carriage to reciprocate in response to forward and backward rotation of a shifting shaft and at at least one end of the range of motion of the carriage the shifting shaft can continue to freely rotate even though the carriage cannot.

Abstract: A clutch mechanism designed to include a free-wheeling unit which is disengageable in the driving direction consisting of a clutch hub and a clutch sleeve which cooperate with locking catches, with the clutch sleeve being embraced by a control ring. Control pins are radially guided in the clutch sleeve and, by turning the control ring relative to the clutch sleeve, inclined faces formed on the control ring act on the control pins to actuate the locking catches to permit disengagement of the driving connection.

Abstract: Propulsion and speed change mechanism for lever propelled bicycles having a pair of propulsion levers 4, each of which is built in one piece with a speed change arm 3 and mounted in each side of the main shaft portion 2 at the bottom of the bicycle frame 1. A rear axle 5 and a hub 6 is mounted on the rear shaft portion 2'. A one-way clutch mechanism has roller-type free wheels 11a installed at both ends of the rear axle. Chains 7", the ends of which may be connected together with a see-saw cable 7', are entrained around gears 7 and guide rollers 13. The free ends of the chains are connected by connecting bars 14 having pins to the speed change arm 3. Pivotally mounted members 15 of triangular shape and a cam bar 17 operated by a speed control knob 18 are used to change the effective length of the arm for speed control.

Abstract: A locking lever is articulated to a latch. The locking lever is pivoted or swung out against the action of a spring and the pivoting or swinging movement is limited by a stop mounted at an eccentric. The opposite pivoting or swinging movement of the locking lever is limited by a surface at the locking lever which runs-up against a surface at the latch. Upon rotation of a drive shaft carrying the eccentric the latch can now assume a decoupling or decoupled position. Due to the provision of control levers with hook-shaped ends which, when pivoted into a predetermined position, cause the locking lever to run-up or travel against one of the hook-shaped ends, the latch is only then caused to be decoupled when subsequently and in accordance with the weaving program a decoupling operation of the latch is really intended to take place. Otherwise the latch is not decoupled because in that case the locking lever cannot run-up against one of the hook-shaped ends of the control levers.

Abstract: Rotary input power is selectively coupled to an output shaft or the like by actuation of a plunger which forces a movable pin into a coupled relation between a member attached to the input drive and an arm attached to the output. A fixed wall establishes a guideway for the head of the pin until it reaches an aperture in the wall allowing pin extraction as by a spring, gravity or the like. Coupling is established by the pin passing through a hole in the arm attached to the output and a detent or transverse surface associated with the driven element. The device permits coupling a continuously rotating input to an output for one revolution although more or less than full revolutions are possible.

Abstract: An overload clutch assembly including a driving member and a driven member having torque transmitting balls operatively disposed therebetween in apertures in the driving member and engageable in recesses in the driven member with a control member axially spring biased to hold the balls in the recesses in the driven member to effect the engaged condition of the clutch. The control member is circumferentially movable relative to the driving member against the action of biasing springs to bring recesses in the control member into alignment with the torque transmitting members so that the clutch assembly can be moved to the disengaged condition. The control member includes a first radially outwardly extending cam which is engageable by a radially movable external control tappet to cause circumferential movement of the control member for bringing the clutch into the disengaged condition when required other than in response to torque overload.

Abstract: The clutch contains a spring for pulling the arm of the control lever on the stop and an additional auxiliary spring connected with a roller. While the control lever strikes on the stop, the roller moves toward one lever arm so that in a further rotation of the parts, the roller (30) is lifted within a slot while additionally tensioning the auxiliary spring. While the tension of the main spring decreases, that of the auxiliary spring increases correspondingly, so that the control lever is held with sufficient tension on the stop and machine vibrations during the striking or operation can be made harmless or damped.

Abstract: A liquid fuel combustion apparatus comprises a combustion cylinder for supporting a wick to be vertically movable between a combustion position and an extinguished position, a rotating shaft connected to said wick for raising and lowering said wick, a driving motor, rotational force transmitting mechanism for rotating the shaft in one direction to thereby raise the wick to the combustion position, the rotational force transmitting mechanism being automatically disengaged from said rotating shaft when the wick arrives at the combustion position, a spring charged with the rotational force in the other direction of the rotating shaft as a result of the rotation of the rotating shaft in the one direction, holding mechanism for preventing the rotation of the rotating shaft in the other direction by the spring so as to hold the wick in the combustion position, and releasing mechanism for releasing the holding operation of said holding mechanism.

Abstract: The link disposed about the eccentric carries two stop elements in the form of rollers. When the pawl is engaged with the driving shaft, the stop rollers move in respective oval paths so as to engage and swing out the control levers to insure that the control levers do not accidentally swing inwardly into the path of the moving pawl or latch locking the pawl in coupled relation with the shaft. The stop rollers also permit an overstroke of the bar to occur in which there is a clearance between the bar and the reversing position of the stroke meter. In this way, the stroke of the stroke meter can be made smaller.

Abstract: A powered gear driven paper insert and line feed mechanism capable of rotating a platen through one half line spacing increments and which is both power operated and disconnectable for manual operation is disclosed. The platen of the typewriter or printer may be manually rotated using platen or may be electronically rotated by energizing the control magnet, thus engaging the clutch assembly to connect the drive motor to the platen. The clutching assembly is such that two separate clutches are operable to disconnect the platen and gear train from the overall clutch apparatus and also to disconnect the drive motor belt and other related hardware which is driven by the drive motor and belt.

Abstract: A safety device for mechanically-operated apparatus, such as a flywheel-driven punch press, consists of a hook-providing coupling member for mounting on the press crank shaft, and a cooperating coupling member for connection to the apparatus body via a power-absorbing member. The coupling members rest in the coupled position and are moved momentarily to the uncoupled position upon initiation of an operation by the operator. If therefore the movable member of the press continues to move after the normal termination of the cycle the coupled members connect the movable member to the power-absorbing member so that the movable member is brought to a stop before the press die parts can close. A third coupling member is provided for engagement with the second coupling member to brake the movement of the operating member if it should move in the opposite direction.

Abstract: An indexing and synchronizing clutch mechanism is disclosed which allows a driven shaft to be stopped in a precise indexing position and to be restarted from the indexing position in exact synchronization with a drive shaft. The mechanism comprises a rotatable drive wheel having an engagement means and a rotatable driven shaft. A pawl means is mounted on the driven shaft for rotation with the shaft. The pawl means is also movable into and out of engagement with the engagement means on the drive wheel whereby the driven shaft is rotated in synchronization with the drive wheel. Actuatable means are provided for moving the pawl means into and out of engagement with the drive wheel. A fixed stop is mounted adjacent to the drive wheel and is adapted to prevent rotation of the pawl means and to hold the position of the pawl means when it is moved out of engagement with the drive wheel by the actuatable means whereby the drive shaft is held in an indexing position.

Abstract: Suction feet are arranged to pick up and feed a sheet from a stack and a blower is arranged to blow air against the edges of the sheets on the stack to separate the top sheet from the rest. A cam assembly driven through a novel one-rotation clutch moves a piston in a cylinder which is connected to both the feet and blower so that the piston is moved in one direction to supply pressurized air to the blower and subsequently in the opposite direction to apply suction to the suction feet. A cylindrical presser member is carried by each suction foot which extends past the suction foot to bend the top sheet during pickup and further aid in separating the top sheet from the lower sheets.

Abstract: A rotary power transmitting shaft decoupling device has a driving element sposed coaxially within a driven element and keyed thereto by a plurality of rollers held in aligned grooves and slots of the driving and driven elements, respectively, by an indexing ring that is coaxial with and surrounds the driven element. Actuation to effect decoupling is effected by arresting rotation of the indexing ring until the rollers become aligned with slots in the ring through which the rollers are ejected.

Abstract: The pawl is retracted from the intermittently rotatable input shaft via a controlled abutment and a spring biased lever-mounted or piston-mounted roller. The abutment serves to start retraction of the pawl while the spring biased roller presses against a non-circular surface of the cam plate on which the pawl is mounted to complete removal of the pawl from the recess. The cam plate also has one or more cam surfaces for resetting the abutment after the pawl has been engaged in the shaft.

Abstract: A delay mechanism for providing a delay in the spin cycle of an automatic washer is operated by means of a pawl pivotable about a stud rotating on an eccentric, which in turn is engageable with a spin gear only in one direction of rotation, and thereby provides a delay of substantially one revolution of the eccentric upon a change in direction of rotation of the eccentric.

Abstract: An article accumulation conveyor in which the drive for moving the articles is automatically discontinued for a selected section of the conveyor when an article is stopped on another certain section of the conveyor and is started again automatically when the article moves. The power for activating the stopping and starting instrumentalities is furnished in its entirety by the conveyor drive so that all need for extraneous power sources or force exerted by a moving article is entirely eliminated.

Abstract: This invention relates to a coupling device and especially a coupling device operable by a dead-man's handle on a lawnmower. When used in a lawnmower the coupling device couples the motor shaft to the cutting blade. A spool has a hole in it that surrounds the shaft. A rotary connecting device normally couples the spool to the shaft so that the spool and shaft rotate together. A disconnect element and brake are operated when the dead-man's handle is released to disconnect the spool from the shaft and subsequently stop the spool. The cutting blade has a central hole through which the spool passes. The blade is in frictional contact with the flanges of the spool and is rotated thereby.

Abstract: An improved clutch assembly includes a rotatable driving clutch part having leading and trailing lug portions thereon and a coaxially rotatable driven clutch part. First and second adjacently-positioned pawl elements are mounted on the driven part for opposing pivotal movements between respective retracted and extended positions, being urged by respective springs to their respective extended positions. In their respective extended positions, the first pawl element is disposed for driving engagement with the leading lug portion while the second pawl element is disposed for engagement with the trailing lug portion so as to prevent any substantial amount of overrun of the driven clutch part relative to the driving clutch part. In their respective retracted positions, the first and second pawl elements are withdrawn from engagement with their respective lug portions.

Abstract: A self-releasing pawl and ratchet clutch is described that is particularly suitable for use as a single revolution clutch in a self-processing camera. At the end of one revolution of the clutch, the pawl is uncoupled from the ratchet wheel by a translatable and pivotable clutch release finger. The finger is spring biased towards a first position and includes a ramp at one end thereof that is locatable in the path of the pawl to stop the pawl from further rotation with the ratchet wheel. In the process of stopping the pawl, the finger is translated from the first position and held by the pawl in a second position against the bias of the spring. After the pawl is unseated from its interdental seat on the ratchet wheel the finger is restored by the spring to the first position. An enlarged tooth formed on the ratchet wheel forces the pawl to be moved generally radially outwardly along the ramp so that the pawl is held away from the tips of the smaller teeth of the ratchet wheel.

Abstract: A safety coupling for quickly disconnecting a cutting instrumentality from the power source of a hand-held power tool comprises a pawl on a rotating driving member engaging an abutment on a coaxial driven member. During normal operation a trip arm holds the pawl engaged. When the trip arm is tripped to release the pawl, a latch prevents reengagement of the pawl until reset.

Abstract: Disclosed herein is a centrifugal clutch comprising a rotatable driver, a clutch drum carried for co-axial rotation relative to the driver, a clutch shoe carried by the driver for common rotation therewith and for movement between a position engaging the clutch drum so as to effect common rotary movement of the driver and the clutch drum and a second position spaced from the clutch drum, a loading shoe, a pivotal connection between the clutch shoe and the loading shoe to afford relative movement therebetween, a trigger movably mounted on one of the loading shoe and the clutch shoe for movement between a first position engaged between the clutch shoe and the loading shoe so as to transmit centrifugal force from the loading shoe to the clutch shoe and a second position of non-engagement between the clutch shoe and the loading shoe, and interengaging surfaces on the loading shoe and on the driver operable when the trigger is in the second position for pivoting the loading shoe in response to radially outward mov

Abstract: A reproduction machine having a document scanning system has an improved recycling clutch for operating the system. The clutch has a rotatable input plate and a rotatable output plate. An annular pawl plate pivotally mounted on the input plate has a driving surface which is biased into engagement with a pin on the output plate. A rotatable timing element driven by the input plate periodically contacts a cam surface on the outer periphery of the pawl plate to disengage the driving surface from the pin to effect release of the clutch at intervals greater than a revolution of the input plate. The cam surface maintains the disengagement of the driving surface from the output plate for a sufficient length of time to permit rotation of the latter in the reverse direction greater than one revolution via a biasing spring.