Abstract: An elastic hoist and traction apparatus in which a friction receiving surface is provided at a rotor of a motor, and an overload prevention device is provided at the reverse side to a load on a brake for stopping a driving shaft and between the motor shaft and the friction receiving surface of the rotor or between the motor shaft and the driving shaft, thereby solving the problem created in that the overload prevention device is provided at the load side of the brake.

Abstract: A liquid pumping system adaptable for connection to either an electrical drive motor or an internal combustion engine, wherein a generator and clutch is coupled to the driving source, and a pressure sensing switch is connected to the generator rotor to selectively provide voltage to a rectifier circuit and field winding for the clutch. The energization of the field winding causes the clutch to actuate and thereby causes a mechanical coupling to a reciprocable pump for developing liquid pressure.

Abstract: The present invention relates to a rotary machine. Main technical problem is in that two rotating forces being different in the rotating direction are taken to the outside using one motor. Consequently, in the invention, a stator (3) is rotatably supported by a support body (2) and provided with an output shaft or an input shaft (34), and further static side and rotating side are electrically connected. The rotary machine according to the invention can be applied as the drive source of a load requiring the rotating force in different rotating direction, or can be applied as a generator by the power source of wide range and other wide use ranges.

Abstract: A miniature electric motor having a magnetic clutch wherein the clutch includes a metallic element and a non-metallic element; the non-metallic element being operative to preclude physical contact between the motor and the metallic element of the clutch.

Abstract: An electric clutch actuator includes a coil having first and second windings, a first end of the first winding being connected to a source of electrical power and a second end of the second winding being connected through a switch such as an FET (field effect transistor) to ground potential. The opposite ends of the windings are connected together through another FET switch to the ground potential. An actuation circuit is responsive to a control signal to turn on the FET switches and cause electrical current to flow primarily through the first winding. The actuation circuit includes a timing circuit which turns off the FET connected to the opposite ends of the windings after a predetermined period of time to cause electrical current from the power source to pass through both of the windings.

Abstract: An actuator which comprises a reversible motor, a solenoid, movable clutch disc to be attracted by the solenoid, a driving clutch disc supported rotatably between the movable clutch disc and the solenoid and driven by the motor. The movable clutch disc and the driving clutch disc are provided with teeth to be engaged with each other and having inclined engaging flanks so as to be disengaged from each other due to slippage caused between the inclined engaging flanks of the teeth. According to this invention, it is possible to interrupt a force larger than a predetermined value and transmit reliably a smaller force to prevent damage to the throttle members.

Abstract: A servo-actuator has a motor driven input pinion engaging a driven gear clutched to an output pinion. The driven gear has an internally notched hub and the output pinion has a central core with a tapered pin slidable therein. Spherical cams are slidably received in a cross hole and are moved outward to lock the output pinions to the hub when a solenoid is energized, to move the tapered pin into contact with the cam members. The angle of the notch and the pin taper are chosen to effect a positive de-energization force on the pin for facilitating disengagement.

Abstract: A reaction containment drive apparatus for a power tool includes a motor having an outside case free to rotate within the tool casing, and an internal drive shaft. A planetary gear set is an integral portion of the drive. It has three parts, namely, a central sun gear part, a middle planet gear part (the planet gear part having a planet carrier and preferably three planet gears on the planet carrier), and an outside ring gear part coaxial with the sun gear part and the planet carrier. The planet gear part is rotatable between the sun gear part and the ring gear part.

Abstract: A rotor for a generator includes a core made of a plurality of magnetic plates laminated with each other, a magnet received in a holding portion of the core, and a synthetic resin mold molded on the core in the circular disc shape. A pawl is rotationally supported on the resin mold by means of a support shaft, and a stopper is formed on the support shaft or the resin mold. The stopper allows the pawl to engage the resin mold but prevents the pawl from disengaging from the resin mold. In case a conical opening is formed, a tapered punch may be pushed into a central opening of the core, so that a conical opening and thickened portion are formed on the core. The core can be directly connected to a crank shaft.

Abstract: A polyphase induction motor prevents the transmission of excessive torque to the load upon starting of the motor by connecting a pair of friction clutches between the rotor of the motor and the power shaft. When a torque higher than the pressure on the clutches occurs, the clutches will slip, permitting the output shaft to rotate at a lower speed than the rotor. An adjustment varies the pressure of a spring pressing on the clutches to adjust the torque at which slippage of the clutch occurs.

Abstract: An electromagnetic clutch includes a clutch rotor having a first friction surface and an annular armature plate having a second friction surface. The first friction surface and the second friction surface face each other. A friction member made of nonmagnetic material is fixedly disposed within a second groove formed at the second friction surface of the annular armature plate. A first end surface of the friction member projects with respect to the second friction surface of the annular armature plate. The first friction surface of the clutch rotor is provided with a first annular groove to receive the projecting portion of the friction member. Therefore, the depth of the second groove becomes smaller. Consequently, the number of magnetic lines of flux which radially penetrate through an annular portion of the annular armature plate at the location of the second groove is enhanced.

Abstract: A rotary drive mechanism includes a rotary solenoid having a stator and multi-poled rotor. A moving member rotates with the rotor and is biased by a biasing device. The biasing device causes a further rotational movement after rotation by the rotary solenoid. Thus, energization of the rotary solenoid moves the member in one direction to one position and biases the biasing device against the member. Subsequently, de-energization of the rotary solenoid causes the biasing device to move the member in the same direction to another position from where the moving member is again movable by energization and de-energization of the rotary solenoid. Preferably, the moving member is a multi-lobed cam having the same number of lobes as the rotor has poles. An anti-overdrive device is also preferably provided for preventing overdrive in the forward direction or a reverse rotation of the moving member and for precisely aligning the moving member.

Abstract: An exercise device is described in which a flywheel fitted in a frame structure and rotated by a rider is provided with a brake mechanism for selectively braking the rotation of the flywheel, as desired. The brake mechanism comprises a copper strap fitted on the periphery of the flywheel and permanent magnet pieces attached to an arch pivotably mounted to the frame structure. The position of the arch is adjustable so that the distance of the magnet pieces from the copper strap varies in a predetermined manner to achieve a desired braking effect. To achieve a simple and clear display a two-arm lever is pivotably attached to the frame structure, the shorter arm of which being arranged to make contact with the arch and to follow the movements thereof. The end of the longer arm of the lever is arranged such that, when moved in response to movement of the shorter arm, acts as a basis for a display indicating the braking effect of the flywheel.

Abstract: A viscous clutch (10) is typically employed in a fan drive mechanism within a truck or automobile. A shaft (18), driven by the engine (12), rotates a clutch member (42) within the fan drive. The clutch member is arranged for fluid engagement with a body member (60) for the transmission of torque thereto when fluid is disposed in an operating chamber (100) defined by complementary shear surfaces in the clutch and body members (48,98), respectively. An actuator assembly (30) operates to displace a valving element (196) within the clutch to control the torque transmission therethrough and thus the speed of the output shaft and fan (34) thereof. The actuator is electrically powered by a generator (222) made up of an armature (224) carried by the body member and a plurality of field generating magnets carried by clutch member (42) for rotational interaction therebetween.

Abstract: A reverse rotation preventing mechanism for synchronous motors includes a stopper interposed between a frame of a synchronous motor and a suitable stationary member, the stopper, including a stopping portion having elasticity and a rotating member fixed to a rotor shaft of the synchronous motor, and the rotating member, including a metallic flywheel and a gear disposed on the central portion of the flywheel, the flywheel having an engagement portion. The engagement portion of the flywheel of the rotating member is engaged with the stopping portion of the stopper when the synchronous motor is rotated in the direction opposite to a predetermined direction.

Abstract: A coaxial type starter comprises a motor having a tubular armature rotary shaft, an electromagnetic switch located at the rear part of the motor and having an operating shaft arranged in the same axial line as the armature shaft, an overrunning clutch for transmitting a rotating force only in one direction, and a pinion shaft which is disposed in the armature shaft to receive the rotating force thereof through the overrunning clutch. The front end portion of a clutch inner member in the overrunning clutch device is supported by a bearing which is fitted to a front bracket; the pinion shaft is so arranged that it is engaged with the inner circumference of the clutch inner member through a spline, and pinion teeth formed at the front end of the pinion shaft are radially overlapped by the bearing.

Abstract: A one-way clutch for a reduction-geared motor having a reversible electric motor and reduction gears allows an output shaft thereof to rotate in a normal direction and firmly prevents the output shaft from rotating in a reverse direction when the reversible electric motor is not fed. The one-way clutch includes a transmission gear supported on the output shaft wherein a sawtooth is provided on one side of the transmission gear. A clutch, axially movable relative to the output shaft, has a sawtooth facing the sawtooth of the transmission gear. The clutch also provides a radially located rotation-prevention portion. A compression spring is included for urging the clutch for the transmission gear in a direction along the axis of the output shaft. A stopper pin in the gear casing is inserted into the rotation prevention portion of the clutch. An electromagnet in the gear casing urges the clutch in a direction opposite to the direction urged by the compression spring when the electromagnet is fed.

Abstract: An electromagnetic clutch is disclosed which includes a rotor having a friction surface and an armature plate having a friction surface. Both friction surfaces face each other. An annular friction member of non-magnetic material is fixedly disposed on the friction surface of the armature plate. The thickness of the annular friction member is gradually decreased from its radially-outer edge to its radially innermost edge, thereby preventing the restriction of the number of magnetic lines of flux which radially penetrate through the armature plate. The decreasing thickness increases the magnetic attraction between the armature plate and the rotor without increasing the weight of the electromagnetic clutch.

Abstract: A soft start, self-powered coupling for connecting a motor to a load, the coupling including a magnetic particle clutch, a generator having a rotor carried by the clutch and a stator, and an electronic control circuit assembly carried by the generator rotor, the magnetic particle clutch being connector to the motor and to the load, the generator powering the electronic control circuit assembly and the clutch to provide linear timed acceleration of the load.

Abstract: A starter comprising an electric motor which produces torque for staring an engine has a hollow outer member included in a one-way clutch and supported by a cover so as to be rotated together with the hollow armature shaft of the motor; a hollow inner member included in the clutch and surrounded by rollers is provided inside the outer member. A pinion shaft with a pinion capable of being engaged with the ring gear of the engine is engaged with the inside of the inner member by splines so that the pinion shaft is movable in the axial direction thereof; and an electromagnetic switch applies electricity to the motor and moves the pinion shaft in the axial direction thereof.

Abstract: A rotary electric drive device for use in a vehicle anti-skid braking system has a rotary armature supported by a thrust race in relation to a housing. One part of the thrust race has external teeth for co-action with a pawl which is disengaged from the teeth for one direction of rotation of the armature but engages the teeth during rotation in the other direction to lock the race part to the housing. When this happens, slipping occurs between opposed contiguous faces of the armature and part respectively in order to dissipate some of the rotational energy of the armature when the drive device is de-energized.

Abstract: An electromagnetic device such as an electromagnetic brake or an electromagnetic coupling comprises an electromagnet, at least two parts arranged so that, when the electromagnet is switched on, a magnetic flux extends through the parts. Formations reducing residual magnetism in the parts, including a plurality of gaps formed as slots, are provided in at least one of the parts, such that this part remains a one-piece member.

Abstract: In an engine starting and charging device mounted between an engine body and a clutch, major parts of the clutch 16 are disposed in a recess 25 formed in the axial direction in the end of the revolving-field pole 102a on the clutch side, to decrease the axial length from the engine to the clutch.

Abstract: A linear actuator is provided with an electric motor rotating a drive pinion gear in mesh with an intermediate gearing arrangement which in turn is in mesh with a main drive gear for rotating a drive screw journalled within a main body housing. Rotation of the drive screw causes longitudinal advancement of a drive nut axially advancing an extension rod bearing to move an output load connected to an opposite end of the extension rod. The intermediate gearing arrangement includes a lost motion mechanism allowing the drive pinion to complete approximately one revolution before imparting rotative torque to the drive screw allowing the drive motor to develop an operating torque to prevent lockup of the actuator. The lost motion mechanism includes a pair of arcuate slots formed in a first intermediate gear in contact with the drive pinion and a pair of dowel projections projecting from a second intermediate gear into the slots. The second intermediate gear is connected to the drive screw.

Abstract: A permanent magnet, alternating current motor having a variable hysteresis output coupling has an annular permanent magnet rotor caused to rotate within a stator structure. This permanent magnet rotor is capable of being shifted laterally to engage or disengage a hysteresis drag cup output device. With this arrangement either an off-on output torque can be provided, or the output torque can be modulated.

Abstract: An electromagnetic clutch includes a clutch rotor and an annular electromagnet. The clutch rotor has a rotor which sectional side view is a U-shaped configuration and a pulley mounted at an outer peripheral surface of the rotor. The annular electromagnet is disposed in an annular cavity of the rotor. An armature plate facing to a front end surface of the rotor is supported elastically by a stopper plate through a plurality of leaf springs. The stopper plate is fixed to an outer end of a drive shaft. First engaging elements are formed at an outer peripheral surface of the rotor. Second engaging elements are formed at an inner peripheral surface of the pulley. The first and second engaging elements are complementary and prevent the relative rotational motion of the pulley and the rotor when engaged. A stopper provided on the outer peripheral surface of the rotor prevents the relative axial movement of the pulley and the rotor.

Abstract: A temperature activated fan assembly preferably for an electric motor. The assembly includes a fan, a torque transfer means engagable with the fan for transferring torque to the fan and a first member which expands in response to a temperature increase. The expansion of the first member causes the torque transfer means to engage the fan. The first member is situated within the motor such that the first member causes the fan to operate when a critical temperature in the motor is reached. The first member can be fabricated as a rod or coil from a material having a suitably high coefficient of thermal expansion. The first member can also be fabricated from a memory material.

Abstract: A torque coupling device of the synchronous reluctance type having a magnetic flux generating device and concentric rotors, each rotor having a sleeve of diamagnetic material including a plurality of flux windows, the diamagnetic sleeves on the two rotors cooperating to provide a reluctance gradient within a magnetic circuit, thereby variably magnetically linking the two rotors.

Abstract: An engine starter includes an electric motor having a hollow rotary shaft for causing a turning force to start an engine, a hollow inner clutch rotatably supported in the hollow rotary shaft through a one-way clutch, a pinion shaft provided with a pinion which is engaged with a ring gear of the engine, a spline-fitted in the hollow inner clutch to move in the axial direction thereof, an electromagnetic switch attached to one end of the electric motor for turning on or off the electric motor, and a moving body which moves in conjunction with the electromagnetic switch to move the pinion shaft in the axial direction thereof to engage the pinion with the ring gear.

Abstract: A coaxial type starter used to start an engine of a vehicle is disclosed. The starter includes a d.c. motor having an armature rotary shaft which incorporates an overrunning clutch and six or more magnetic poles which are defined by permanent magnets disposed circumferentially on the inner surface of a tubular yoke for forming a magnetic path. Provision of six or more magnetic poles on the inner surface of the yoke enables a reduction in the thickness of the yoke and the diametrical thickness of the armature core since the required thicknesses of the yoke and the armature core are inversely proportional to the number of field magnetic poles. Accordingly, it is possible to incorporate the overrunning clutch inside the armature rotary shaft without any increase in the overall diameter of the starter. Thus, it is possible to achieve a reduction in the overall size of the starter.

Abstract: An electromagnetic clutch includes a first rotatable member supported on a first bearing, and connected to an external driving source having an axial magnetic end plate. A second rotatable member is connected to a driven member. An annular magnetic member is supported on the second rotatable member through a plurality of leaf springs so as to be capable of axial movement, and faces the axial end plate of the first rotatable member with an axial gap therebetween. A third rotatable member is connected to the second rotatable member, to limit the axial movement of the annular magnetic member. An electromagnet is associated with one of rotatable members and the annular magnetic member for transmitting rotational force from the external driving source to the other of the rotatable members.

Abstract: An electric hand tool with a detachable switch mounted between the handle and a detachably mounted nosepiece to allow easy access to, and replacement of, the switch in case of malfunction. The nosepiece is movable in response to pressure on the workpiece. Movement of the nosepiece closes the switch for activating the motor.

Abstract: A motor with an integral magnetic torque limiting coupling which maintains the relative positions of the motor rotor and a coupling output shaft thereof when the rotor is rotated, and transmits up to a predetermined amount of torque during such rotation, which exceeds the maximum sustained torque which the motor develops during normal operation so as not to interfere with the torque transmission during normal operation of the motor while allowing the output shaft and rotor to slip relative to one another to prevent transmitting a torque above a maximum safe torque which may be safely applied to a gear train to be driven by the motor, thereby preventing damage to the gear train by the motor in the event of a sudden change of speed of the gear train.

Abstract: An electromagnetic clutch of the type which includes a rotor secured around a rotation shaft, a drive member rotatably mounted around the rotation shaft, an armature mounted through a resilient member to the drive member with a gap to the rotor, a bearing mounted around the rotation shaft, a yoke mounted around the bearing for rotation about the rotation shaft, and the yoke locking mechanism for locking the yoke to a frame so as to prevent the yoke from accompanying the rotation shaft when the rotation shaft is rotated, the yoke having a coil wound therearound, and in which the rotor, the armature and the yoke are arranged to form a magnetic path so that the armature is electromagnetically attracted to the rotor for transmitting torque from the drive member to the rotation shaft when the coil is energized.

Abstract: A wiper motor assembly including an electric motor and a speed reduction gear which are combined as a unit. A clutch assembly is incorporated with the speed reduction gear to cut off a gearing connection between a driving shaft of the motor and an output shaft of the speed reduction gear when the output encounters a certain level of resistance to rotation.

Abstract: In motor-operated machines, especially portable electric tools, it is essential to prevent an impermissibly high torque on the driveshaft or operating spindle. This is attained by means of a torque-disengagement mechanism. An especially elegant, compact, precisely responsive torque-disengagement mechanism is attained by mounting one of the two bearings for a driveshaft in the machine housing or similar structure in such a way that it can move across the longitudinal axis or radially far enough to initiate a switching procedure. The bearing is secured in an initial position by means of an opposing force. The position represents both the zero position for the switching procedure and the correct position of the axis of the driveshaft during operation. If the machine includes a means of varying the torque, the power of the opposing force can be adjusted and maintained either continuously or discontinuously.

Abstract: An electromagnetic clutch apparatus for providing a reversible mechanical linkage between a driving motor and its mechanical load and which is particularly well suited for use as part of an electrically actuatable automotive cruise control system. The apparatus is inherently self-disengaging, thereby limiting the maximum mechanical load against which the driving motor may operate. The apparatus is designed to be placed between the final output gear of a gear train and the engine throttle and yet overcomes the problems associated with such a placement because the mechanical torque which the clutch is designed to transmit is not directly related to the electromagnetic force required to keep the clutch engaged.

Abstract: An electromagnetic clutch is disclosed comprising a rotor and an armature plate with improved frictional surfaces. The armature plate is disposed to face the rotor with a predetermined axial gap. The rotor or the armature plate is provided with a contact surface which contains spiral concaves and projections with a predetermined pitch. This surface has a layer of metal plating with a hardness lower than that of the magnetic materials which make up the rotor and armature plate.

Abstract: A mechanism prevents the start-up of a synchronous a.c. motor in other than a desired direction. The mechanism includes a flexible arm having a finger that will engage a radially projecting abutment on the motor shaft. The finger blocks rotation of the shaft in a first direction and slides over the abutment when the shaft rotates in the opposite direction. A solenoid moves the arm and finger out of the path of the abutment shortly after the motor is energized, to allow the shaft to rotate in the first direction if the motor encounters an overload. Alternately, the arm may be formed of a bi-metal which is differentially heated by electrical current following motor energization to move the arm out of the path of the abutment.

Abstract: A motorized drive attachment for rotating a rotatable control shaft in a telescope. The attachment includes a motor within a housing, and a coupler on the output shaft of the motor interiorly lined with an O-ring. A snap-on bracket, secured to the housing detachably clamps onto a frame portion of the telescope, and in this position holds the attachment in place with the coupler providing a direct drive to the control shaft. The O-ring acts as a slip clutch when the control shaft is operated manually.

Abstract: An electromagnetic clutch comprising a rotor and an armature plate with improved frictional surfaces. The armature plate is disposed to face the rotor with a predetermined axial gap. The rotor and the armature plate are provided with contact surfaces, each of which contains spiral concaves and projections with a predetermined pitch. At least one of the surfaces of the rotor or armature plate has a layer of metal plating with a hardness lower than that of the magnetic materials which make up the rotor and armature plate.

Abstract: A drive unit for direct drive of an information-storage disk comprises a collectorless D.C. external-rotor motor having a permanent-magnet rotor magnet arrangement of considerably reduced axial length. Electrostatic charge is removed from the rotor shaft by a metallic spring element which engages the shaft periphery from within the interior of the rotor housing. An electromagnetic braking arrangement is located interiorly of the housing. The packet of stator plates for the stator has an axial length shorter than that of the rotor magnet arrangement, but is provided at its axial end faces with skirted-rim flux-conducting elements whose peripheral skirt portions form useful-air-gap extensions in cooperation with the rotor magnet arrangement.

Abstract: An adjusting device with an overload slip system and a slip-independent position indicator includes a driving system and an adjusting member movable by the driving system between two end stops. The driving system includes an electric motor housed in a housing and a planetary transmission connected to the motor shaft, the power output shaft of the transmission being in engagement with the adjusting member. A stationary, internally toothed ring of the planetary transmission is confined between facing peripheral edges of the divided housing and is capable of slipping relatively to the edges of the housing under overload conditions. A support plate with a circular electrical resistor is fixedly connected to the housing on the side of the power output shaft. A runner contact connected to the power output shaft is movable over the resistor.

Abstract: A lost motion clutch assembly is disclosed which has first, second, and third clutch members. The first and third clutch members are mounted coaxially and contain a plurality of recesses in the surfaces facing each other. The second clutch member is disposed between the first and third, and preferably includes a plurality of balls disposed in arcuate recesses in the first and third clutch members. Each recess has two terminating ends forming engagement shoulders to engage a portion of the balls at the termination of each of the two directions of rotation. Upon inital rotation of the first clutch member in a first rotational direction, the third clutch member is not rotated until a ball has come into contact with the opposite end of the recess in the first clutch member 31 and also in engagement with the opposite end of a recess in the third clutch member. By this construction, an additional angle of angular lost motion is achieved for a given number of balls.

Abstract: To facilitate manufacture and increase the lifetime of a speed-dependent coupling between the ventilation or fan wheel (23) and drive shaft (18, 21) of the alternator, an inner race (25) is secured to the drive shaft, formed with two parallel running grooves (26, 27) in which two rows of balls (28, 29) are rolling. A pair of outer races is formed as ring-shaped elements (30, 31), of part-circular cross section, surrounding opposite, at least approximately quarter-circular zones of the balls, the outer races being axially biased towards each other by a pair of disk-shaped membranes (34, 35) to which the ventilation fan wheel (23) is attached, the membranes being biased towards each other by a biasing force (F), for example exerted by axial screws, securing the disk-shaped membranes together for resiliently biasing the ring-shaped elements towards each other and exerting axial pressure on the balls (28, 29) running in the grooves of the inner race and beneath the outer races.

Abstract: A linear actuator having a rotor sleeve coupled through a thread to an output spindle, and a rotor-magnet sleeve surrounding the rotor sleeve for driving it. The rotor is maintained in step with the driving circuit even though the output spindle may have struck a stop, by providing a slip clutch between the rotor-magnet sleeve and the rotor sleeve.

Abstract: An arrangement for cooling an electric rotating machine such as an alternator of an automotive vehicle by means of a fan which is intermittently driven in accordance with the cooling requirements of the electric rotating machine. A heat source is associated with the electric rotating machine which is representative of the degree of heating of the rotating machine. The heat source may be the radiator of the rectifier diodes of the alternator. A heat sensitive means in the form of a spring of "memory alloy" controls the coupling/uncoupling with respect to the shaft of the rotating machine of the fan which is mounted free for rotation coaxially of the shaft of the machine. The heat sensitive means is in heat exchange relation with the heat source. The spring, for example, operates a lever which activates a control rod passing through the hollow shaft to control the coupling or clutching of the fan with respect to the rotating shaft.

Abstract: This invention employs the structure that the clutch mechanism is provided between the rotating shaft (4) of a smallsize motor itself and the reduction mechanism (21) and said clutch mechanism is coupled or decoupled by a magnetic force generated by the excitation coil (2) of the motor and the spring means (19) giving a force in the direction opposing to said magnetic force.

Abstract: A starter motor includes an electric motor, an epicyclic reduction gear mechanism driven by the electric motor, and a pinion gear wheel driven from the output member of the epicyclic reduction gear mechanism. The output member of the epicyclic gear mechanism is the planetary gear carrier of the mechanism and the annular gear of the mechanism is held against rotation relative to the frame of the starter motor by a torque limiting clutch, which slips when the annular gear is subjected to a torque in the direction opposite to that to which it is subjected during cranking of the associated engine, and in excess of a predetermined value, thereby limiting the torque to which the epicyclic gear mechanism and the remainder of the starter motor drive train is subjected.

Abstract: The invention relates to lock mechanisms by which a missile or analogous tem may be prevented from undergoing an undesired launch or ignition. Specifically, the invention is a rotating lock mechanism which may be rotated in precise clockwise and counterclockwise steps by an electrical stepper motor or other source of precise rotation, in response to a predetermined sequence of electrical pulses.