Abstract: An output rotary shaft 12 of a coaxial engine starter has at one end thereof a pinion 19 engageable with an engine ring gear and is inserted at the other end into a tubular armature rotary shaft 11a of a motor. A clutch inner member 15b of a unidirectional clutch having helical splines formed in its inner circumference is engaged with a helical spline portion 12a formed on the armature rotary shaft. The engine starter further comprises a bearing surface 21a; 26 on the clutch inner member and a bearing 13 fitted within the inner circumferential surface of the tublar armature rotary shaft, and the output rotary shaft is supported by the bearing surface of the clutch inner member and the bearing.

Abstract: An engine starter motor comprising an electric motor, a unidirectional clutch connected to the motor and having an output shaft, the unidirectional clutch exhibiting a drag torque appearing when the unidirectional clutch is being rotated in an idle direction, a speed reduction unit connected to the unidirectional clutch, and a pinion shaft having a pinion gear for engaging and driving an engine ring gear and connected to the speed reduction unit through helical splines. The drag torque T of the unidirectional clutch is determined to be equal to or smaller than a drag torque To, at which a return force F on the pinion shaft with an over-running clutch mounted thereon does not exceed an operating force on the pinion shaft by a solenoid, divided by a speed reduction ratio g between the over-running clutch and the pinion shaft.

Abstract: A starter motor for use with an internal combustion engine, which incorporates an idler gear that is constantly engaged with a translatable pinion gear to provide starting engagement and rotation to a driven gear on the engine.

Abstract: An engine starter apparatus being arranged such that a rotational force from an electric motor is transmitted to an output rotary shaft through a planetary speed reduction gear. The number Zs of teeth of a sun gear, the number Zp of teeth of a planet gear, the number Zi of teeth of an internal gear and the number N of the planet gears satisfy the equation (Zs+Zi)N=an integer, and the pressure angle .alpha.bi of the engagement between the planet gear and the internal gear is arranged to be cos.sup.-1 {(Zi-Zp)/(Zs+Zp).times.cos.alpha.bs}, where .alpha.bs is the pressure angle of the engagement between the sun gear and the planet gear.

Abstract: A starter comprises an electric motor which produces torque for starting an engine; a speed reduction planet gear unit in which a carrier by which a plurality of planet gears are rotatably supported is integrally formed with a rotary shaft disposed coaxially with the armature shaft of the electric motor, so that the rotary shaft is rotated at a lower speed than the armature shaft as the torque of the armature shaft is transmitted to the rotary shaft; an output rotary shaft provided with a speed reduction gear engaged with the gear formed on the rotary shaft; and a pinion supported on the output rotary shaft so that the pinion can be engaged with and disengaged from the ring gear of the engine and can be rotated by the torque of the inner member of the clutch.

Abstract: In a starter having a planet gear speed reducer, an impact stress receiving mechanism is made up of components suitable in configuration for mass production including a ring gear having an internal gear engaged with a plurality of planet gears and axially extended ratchet-shaped teeth on the outer wall. A movable cylinder has teeth formed in the inner wall which are engaged with the ratchet-shaped teeth, and a straight spline gear on the outer wall which is engaged with the starter frame. The movable cylinder is axially slidably mounted on the ring gear. A rubber ring is arranged adjacent to the movable cylinder to absorb the force of moving the movable cylinder axially which is formed when impact stress is produced in the power transmission of the starter.

Abstract: A coaxial engine starter comprising an electric motor having a hollow armature rotary shaft, an axially slidable output rotary shaft rotatably supported in a housing and having at its front end a pinion engageable with an engine ring gear, a solenoid switch disposed behind the electric motor for supplying current to the electric motor and causing sliding movement of the output rotary shaft, a planetary speed reduction gear, disposed in front of the electric motor and having a planetary bracket, for speed reducing the rotation of the armature rotary shaft, an over-running clutch, disposed in front of the planetary speed reduction gear and having a clutch outer member and a clutch inner member, for transmitting the speed-reduced rotation of the planetary speed reduction gear to the output rotary shaft.

Abstract: A coaxial engine starter comprises an electric motor having a tubular armature rotary shaft and an output rotary shaft disposed at the front end of the electric motor and having at one end a pinion capable of engaging and disengaging an engine ring gear and axially slidably inserted into an inner bore of the armature rotary shaft at the other end. The starter also comprises a planetary speed reduction gear for reducing the rotational speed of the armature rotary shaft, an over-running clutch including a clutch inner member fitted on the output rotary shaft for transmitting the rotation of the armature rotary shaft to the output rotary shaft, and a front bracket including an inner front bracket connected to the electric motor and an outer front bracket connected to the inner front bracket is provided. Also provided is a ball bearing having an inner and an outer race for rotatably supporting the output rotary shaft.

Abstract: A coaxial type starter device comprises a d.c. motor, a pinion provided at the front end of an armature rotary shaft of the d.c. motor and an output rotary shaft arranged in alignment with the armature rotary shaft so as to be movable in its axial direction so that a rotating force of the armature rotary shaft is transmitted to the output rotary shaft through a planet gear speed-reducing device and an overrunning clutch device, wherein a carrier for supporting each planet gear wheel has a cylindrical portion at its front end and the cylindrical portion is fitted to the outer circumference of an clutch outer member of the overrunning clutch device so as to cause a relative sliding movement in their circumferential directions when a predetermined torque is produced.

Abstract: A coaxial type starter with an overrunning clutch device has a clutch inner member which is provided with a cylindrical portion formed integrally therewith and extended forwardly; is rotatably supported by first and second bearings spaced apart in the axial direction so that they bear the cylindrical portion; and has a helical spline at the inner circumferential surface so as to be engaged with a helical spline formed at the outer circumferential surface of an output rotary shaft inserted in the clutch inner member so that a rotating force by the armature rotary shaft is transmitted to the output shaft.

Abstract: A starting system having: a recoil type starter disposed so as to be concentric with a crankshaft of an internal combustion engine and to face one end of the same, the recoil starter having a recoil drum having a hollow boss portion and an engaging portion formed at its one side facing the one end of the crankshaft; a motor starter; a rotary shaft inserted into the hollow boss portion of the rotary drum concentrically therewith and capable of being rotated by the motor starter; a shock absorbing spring disposed around the rotary shaft; and ratchet members disposed at the one end of the crankshaft, the ratchet members being capable of respectively engaging with the spring and the engaging portion.

Abstract: In an engine starter having a planet reduction gear mechanism including a planet gear arm formed integrally on a driven shaft of the mechanism and having a plurality of holes and a corresponding number of roller pins pressure-inserted into the holes from one side surface of the planet gear arm and rotatably supporting planet gears, respectively, each hole is chamferred in the other side surface of the planet gear arm to receive a protrusion to be formed in the other side by the pressure-insertion of the roller pin.

Abstract: A plurality of planet pinions are carried on fixed shafts and mesh with a sun gear formed on an armature rotating shaft of a motor; and a cylindrical holder section of an outer clutch of an overrunning clutch device is so disposed as to cover the outer periphery of an internal gear which meshes with the planet pinions and is rotatably supported, such that the internal gear and the cylindrical holder are engaged through helical splines. Therefore, the overall length of the starting device can be decreased by the length of the helical splines formed on a conventional armature rotating shaft section or by a length exceeding it.

Abstract: A starter includes a speed changing mechanism for transmitting rotational force of an electric motor to a pinion gear capable of being brought into or out of engagement with a ring gear of an engine. The speed changing mechanism includes a geared stepless speed changer. A speed reduction ratio is controlled responsive to a load change by means of an input shaft, an output shaft, and input and output frames rotatable relative to each other about the input shaft. A ratio of angular velocities of the input and output shafts is related to an angle of rotation between the input and output frames.

Abstract: A coaxial starter which includes a motor having a tubular armature shaft to which an armature and a commutator are attached; an output shaft arranged at the front end side of the motor and having one end provided with a pinion disengageably engaged with a ring gear of an engine and the other end inserted into the inside path of the tubular armature shaft so as to be axially slidable, the output shaft having a large-diameter portion thereof; a driving power transmission device having an overrunning clutch for transmitting rotation force of the armature shaft through the overrunning clutch to the output shaft; a bearing provided between a front end surface of the armature shaft, perpendicular to the axial direction thereof and the end surface of the large-diameter portion of the output shaft; and an electromagnetic switching unit provided on a rear end side of the motor for energizing the motor and for sliding the output shaft.

Abstract: A starter motor comprising a housing, an electric motor having an output rotary shaft and mounted within the housing, an over-running clutch axially slidably mounted on the output rotary shaft, a solenoid switch for shifting the over-running clutch, and a pinion shifter assembly. The pinion shifter assembly comprises a hollow cylindrical shifter main body placed between the output rotary shaft and the housing in a slidable and rotatable engagement therewith a pinion mounted on one end of the shifter main body for rotation therewith. The shifter main body is connected at the other end thereof to the over-running clutch, and the pinion is a member assembled on the one end of the shifter main body. The pinion may be connected to the shifter main body by splines and a compression spring may be disposed between the pinion and the shifter main body for allowing an axial movement of the pinion relative to the shifter main body.

Abstract: In a starter having a planet gear speed reducer in which the front frame is secured to the end face of the motor with penetrating bolts, a cylindrical packing with ears is mounted on an internal gear with the penetrating bolts inserted into the ears so that, when the penetrating bolts are tightened, the ears of the packing are inscribed in the front frame, while sealingly holding the penetrating bolts, and the packing is compressed between the end face of the motor and the flange of the internal gear, thus eliminating the difficulty that water flows down the penetrating bolts into the motor.

Abstract: A construction of a starter motor for taking off the power to the outside, is operable wherein the power from the starter motor can be taken off as the externally operating section other than the power of an engine. The starter motor includes a first reduction mechanism having a motor shaft as an input shaft. The motor shaft transmits power to a coaxial output shaft. A pinion gear is provided on the engine side of the first output shaft in association with a ring gear. A second reduction mechanism utilizes the first output shaft as an input shaft, to transmit power to a second output shaft. The second output shaft is rotatably coupled onto the first output shaft and coaxial therwith, to permit the power to be taken off to the outside near the pinion gear. The first and second reduction mechanisms each include a sun gear provided on the input shaft, an internal gear and a plurality of planetary gears provided between the sun gear and the internal gear and being mesh with the both gears.

Abstract: The starter motor includes a first output shaft with a pinion gear in mesh with a ring gear of an engine. A first reduction mechanism outputs power from a motor shaft through the first output shaft. A second output shaft and a second reduction mechanism output power from the first output shaft through the second output shaft. The second output shaft is rotatably coupled onto the first output shaft and made coaxial therewith. Power can be taken out on the side of the pinion gear. Both output shafts are associated with each other through a stop member for regulating relative displacement in the axial directions, so that thrusts in directions opposite to the above directions different from each other, which have not been borne, can be borne by each of the output shafts on the other side, respectively.

Abstract: A cylindrical yoke 3 of a d.c. motor of an engine starter having a planet reduction gear mechanism and a bracket 5 fitted on an extension of the yoke without relative rotation therebetween is formed integrally on an inner surface of the extension with internal gear teeth 4 of the planet reduction gear mechanism, which mesh with a solar gear 6 formed integrally on an armature shaft 2 of the motor through planet gears 7 supported by a flange 10 of an output shaft 11 of the starter. The motor is separated from the planet reduction gear mechanism by a flange 3b, 22 arranged therebetween and supporting a bearing 16 which supports the armature shaft.

Abstract: A small engine provided with a self starter motor is suitable for use as a driving mechanism for hand-held or back-carried machines such as cleavers. As the engine is provided with a reduction drive gear loosely inserted over a cylindrical support concentrically provided with a crankshaft, and is so constructed that the rotation of the shelf starter motor is transmitted to the crankshaft via the reduction drive gear and an engagement/disengagement mechanism using centrifugal force, it is possible to improve the durability thereof and to simplify assembly operation.

Abstract: An engine starter is equipped with a motor having a cylindrical armature rotating shaft (3), a clutch mechanism (15) which transmits the rotational force of the motor, an output rotating shaft (17) which is disposed so as to be movable in the axial direction so as to mesh with the clutch mechanism (15), and a solenoid switch (25) which has a moving member (35) which pushes the output rotating shaft (17) in the axial direction by electromagnetic force and which causes a movable contact (39) to contact a stationary contact (40) and supply current to the motor. The rear portion of the output rotating shaft (17) and the front portion of the moving body (35) are both inserted into the cylindrical bore of the armature rotating shaft (3) from opposite ends. The rear bracket (7) of the motor is made from molded plastic.

Abstract: A power transmission, particularly adapted for motorcycle application, in which a first planetary gear reduction system reduces power output from the starter motor for starting the engine and a second planetary gear reduction system operated in cooperation with the first system enables power output from the starter motor to operate the vehicle in reverse.

Abstract: A starter having an epicyclic reduction gear which may be used to start an engine of a vehicle is disclosed. The center bracket and the bearing fitted thereto which have heretofore been employed are eliminated, and instead the armature rotary shaft of a motor is extended forwardly so that a primary output shaft which is integral with a carrier of the epicyclic reduction gear is supported by the extended shaft portion, and the primary output shaft and an outer race of an overrunning clutch are spline-engaged with each other. Thus, it is possible to reduce the overall length of the starter by a large margin as compared with the prior art. Since it becomes unnecessary to employ the driving shaft and other elements which have heretofore been needed, the number of required parts is reduced and it becomes easy to center the carrier of the epicyclic reduction gear and the overrunning clutch. Accordingly, it is possible to improve the reliability of the starter.

Abstract: A coaxial starter motor comprising a d.c. motor having a hollow rotary shaft extended forward and a planetary speed reduction gear having a sun gear disposed on the outer periphery of the rotary shaft. The starter motor comprises an over-runing clutch of which inner sleeve rotates in one direction and is provided at the inner circumference with helical splines, the over-runing clutch being disposed on the front side of the rotary shaft and rotated at a reduced speed by the planetary gear speed reduction gear. Also provided is an output sleeve mounted on the front end portion of the rotary shaft and having a pinion at its front end portion and axially movably and relatively rotatably supported by a bearing, in which helical splines formed close to the rear portion of the outer periphery is in mesh with helical splines of the inner sleeve. A solenoid switch is disposed on the rear end portion of the d. c.

Abstract: A coaxial type starter used to start an engine of a vehicle is disclosed. The starter includes a d.c. motor having a hollow armature rotary shaft incorporating an overrunning clutch, an epicyclic reduction gear having a carrier for supporting a plurality of planet gears which revolve while in engagement with a sun gear formed on a tubular clutch inner member received and supported inside the armature rotary shaft, and an output rotary shaft extending through a tubular member which is formed integral with the carrier, the tubular member being in spline-engagement with the output rotary shaft. Thus, it is possible to reduce the overall length of the starter by a large margin.

Abstract: In order to reduce the space requirements of an internal combustion engine the starter apparatus therefor includes an axially elongated intermediate gear shaft containing gears at each end, one of which meshes with the starter motor pinion and the other of which meshes with the ring gear on the crankshaft.

Abstract: A planetary gear reduction starter, in which for the purpose of improvement of impact absorbing property and breaking-resistance property of an internal gear (11, 30a) receiving pressure of a planet gear (7), an elastic body (22, 31) is mounted on an outer circumference of the internal gear, and the elastic body is disposed in opposition to a housing (5, 21) through a gap/gaps (23; 32, 33) therebetween.

Abstract: An engine starter motor comprises a d.c. motor and a transmission device of high reduction ratio, the d.c. motor having an output shaft connected through the transmission device to an input shaft of an engine. The transmission device includes a wave generator connected to the output shaft of the d.c. motor, an internal gear 20; 48 formed integrally with a housing of the d.c. motor, and a flexible gear 21; 45 having an output shaft connected to the input shaft of the engine and meshing with the internal gear.

Abstract: A coaxial type starter used to start an engine of a vehicle is disclosed. The starter comprises first and second bearings which are respectively disposed between the outer circumferential portion of a carrier of an epicyclic reduction gear which is formed integral with a clutch outer member of an overrunning clutch and a fixed portion of the starter and between the inner circumferential portion of the carrier and the outer circumferential portion of an armature rotary shaft of a d.c. motor. Accordingly, the carrier of the epicyclic reduction gear is prevented from becoming eccentric by the first bearing, and the armature rotary shaft of the d.c. motor which is supported by the carrier through the second bearing is also prevented from becoming eccentric. Thus, it is possible to eliminate any risk of the planet gears of the epicyclic reduction gear being damaged or generating noise.

Abstract: An engine starter in which a driven gear driven by the rotor of a starter motor and an output shaft driving a pinion meshing with the driven gear of an engine are mutually connected through a unidirectional clutch. The gear driven by the rotor and the clutch member driven by the driven gear are rotatably supported by, but separate from, the output shaft. Connection between the driven gear and the clutch member for torque transmission purposes is effected through a torque damper whereby the transmitted torque will be damped and engine noise reduced.

Abstract: A reduction starter employing a planetary gear type reduction gear mechanism having an outer ring gear displaceable radially of a common axis of a central sun gear and an output shaft carrying planet gears for revolution about the common axis. The outer ring gear is formed by an internally toothed ring gear elastically deformable to assure uniform distribution of load torque to all planet gears. The tooth root bending stress of the ring gear is substantially equalized to the outer periphery bending stress thereof to improve the load performance of the planetary gear type reduction gear mechanism and thus reduce the size and weight of the starter. The outer ring gear has an outer rim of a radial thickness t and a plurality of radially inwardly extending teeth each having a height h. The rim thickness t is determined to'fall with a range of from +.ltoreq.0.8 h to +.gtoreq.0.4 h.

Abstract: A planetary gear system for the speed reduction output of a starter motor. The internal gear is made of an elastic resin and is separated from the casing of the system or a metal ring fitted in the casing by a predetermined gap. Thereby, the internal ring can deform over a range of shocks but is prevented from deforming by the casing or metal ring above this shock range.

Abstract: A reverse drive for small vehicles in which an output shaft of a starter motor disposed independently of a driving internal combustion engine can be coupled to a power transmission system between the internal combustion engine and a rear wheel in such a way that the rear wheel is driven in the reverse direction. The starter motor may be capable of normal and reverse rotations, the normal rotation of the starter motor being transmitted to the internal combustion engine through a starting clutch, and the reverse rotation of said starter motor being transmitted to the power transmission system through a reverse clutch. Otherwise, the starter motor may be capable of rotating only in one direction. In this case, the output of the starter motor is transmitted to the output side of the power transmission system through a reverse transmission line while the power transmission system is interrupted.

Abstract: The coaxial type starter device of the present invention has a hollow rotary shaft of the armature of the d.c. motor. A rod is slidably inserted in the armature rotary shaft in its axial direction. One end of the rod is connected to a solenoid-operated switch device and the other end is adapted to push a output rotary shaft.A thick-walled portion is formed in the hollow armature rotary shaft so as to extend from the inner wall in the radial direction so that the thick-walled portion directly supports the rod or indirectly supports the rod through a sleeve bearing.

Abstract: A starter with a gear reduction mechanism including an internal ring gear formed of synthetic resin and a reinforcing member. The internal ring gear has a cylindrical portion and a toothed portion formed on an inner peripheral surface of the cylindrical portion. The reinforcing member is secured around an outer surface of the cylindrical portion.

Abstract: A geared compression air starter having a lead rotor, a driven rotor and a hollow shaft. A driven trunnion of the driven rotor engages with external teeth thereof into external teeth of the hollow shaft to connect the driven rotor with the hollow shaft. A freewheeling unit couples the hollow shaft with an axially displaceable engagement shaft so that the central axes of the engagement and of the hollow shaft can be positioned coaxially with respect to a central axis of the lead rotor. An engagement cylinder is connected with the engagement shaft by means of a piston rod which extends through the lead rotor, and the engagement cylinder is integrated into an end cover of the starter housing.

Abstract: A planetary gear starter with a molded synthetic resin ring gear supported by a frame is disclosed. The ring gear has longitudinally-extending ribs formed in its outer surface which confront longitudinally-extending inward projections formed in the inner surface of the frame. A cylindrical elastic member has an annular portion which is press fit over the ring gear and longitudinally-extending projections which fit into the cavities formed between adjacent ribs and inward projections in the frame. The projections of the elastic member serve as shock absorbers and elastically transmit torque from the ring gear to the frame. The elastic member has an annular portion which reinforces the open end of the ring gear.

Abstract: An improved engine starter has a DC motor with a rotor shaft drivingly connected to an output shaft by a planetary reduction gear, the sun gear of the reduction gear being formed on the outer surface of the rotor shaft and the ring gear of the reduction gear being located on the inner surface of the yoke of the DC motor. The improvement comprises the yoke having a support portion integrally formed thereon which rotatably supports a one-piece end of the output shaft which is connected to the rotor shaft. Preferably, the yoke is formed by deep drawing of mild steel. A dust preventing member forms a labyrinth seal around the rotor shaft and prevents dust from entering the motor from the reduction gear.

Abstract: A gear having a good balance of mechanical characteristics such as shock resistance, wear resistance, and flexible strength is molded from nylon resin containing 3-10 wt % of carbon fibers and 20-40 wt % of glass fibers.

Abstract: A starter for an internal combustion engine comprises a starter motor. A drive shaft extends in coaxial relation to an armature shaft of the starter motor and has a projection extending radially outwardly from an axial end of the drive shaft adjacent the armature shaft. A pinion is in spline engagement with an outer periphery of the drive shaft and in meshing engagement with a ring gear of the engine. The rotation of the armature shaft is reduced in speed and transmitted to the drive shaft through a planetary gear type speed reducing mechanism. A center bracket comprises a cylindrical portion rotatably supported by one of the drive shaft and the armature shaft, and a disc-shaped portion extending radially outwardly from an axial end of the cylindrical portion. A shock absorber unit comprises a rotary disc and a spring disposed around the cylindrical portion of the center bracket.

Abstract: The starting system for an internal combustion engine includes a crankshaft and a camshaft sprocket which form the carrier for a planet pinion set whose elements are continuously engaged with a sun gear mounted and a ring gear mounted by a one-way brake to the engine block. A starting motor is connected by an endless chain or belt to a sprocket connected by a one-way driving connection to the sun gear. An accessory drive pulley and the rotor of the engine oil pump are continuously and directly connected to the sun gear. A hydraulic piston, actuated by engine oil pressure, selectively breaks the ring gear when engine speed is below a predetermined value provided engine oil pressure is at least equal to a predetermined pressure and releases the ring gear when engine speed exceeds the predetermined speed.

Abstract: A reduction gear device is used for a coaxial type starter and is disposed between a rotary shaft of a motor and a rotary shaft of a starter pinion, both shafts being arranged in the same axial line. In the reduction gear, a through hole is formed in a machine frame for a reduction gear to cause air flow and a labyrinth-sealing structure for prevention of dust is formed near the through hole.

Abstract: A reduction type starter, wherein an idle shaft is mounted in a starter housing in parallel with a motor shaft and a pinion drive shaft, and an over running clutch is provided on the idle shaft so that a reduction of rotational speed can be performed at two stages.

Abstract: A reduction starter employing a planetary gear type reduction gear mechanism having an outer sun gear displaceable in directions perpendicular to a common axis of a central sun gear and an output shaft carrying planet gears for revolution about the common axis. The outer sun gear is formed by an internally toothed ring gear elastically deformable to take up an offset, greater than a predetermined value, of any of the planet gears due to irregular mounting thereof, for thereby avoiding local or uneven contact between gear teeth and assuring a uniform distribution of load torque to all the planet gears.

Abstract: The internal speed-reduction type starter comprises a cylindrical armature rotary shaft, a pinion shaft inserted into the cylindrical rotary shaft, an epicyclic reduction gear and an overrunning clutch, placed in the rear of the armature, which connects the rotary shaft with the pinion shaft, an electromagnetic device for causing the pinion shaft to slide in its axial direction to actuate an internal combustion engine.

Abstract: An in-line gear reduction starter drive for driving a pinion from the armature of an electric cranking motor. The drive utilizes a single central shaft that is directly connected to the armature core of the cranking motor armature and the pinion is supported by the shaft. The shaft has an integral gear which forms the sun gear of a planetary gear set. The sun gear drives planet gears which in turn drive a driven member that is rotatably supported by the shaft and which drives the pinion.

Abstract: To prevent transfer of firing or ignition shocks or jolts, and variations in torque transmitted due to compression and decompression of the driven pistons of an IC engine from causing damage to the starter motor, in which the starter motor includes a planetary gearing, (20-25-27), the annulus, or ring gear (20) of the planetary gearing is held in an intermediate bearing structure (10) extending transversely to the starter motor by elastic cushions, or pillows or plugs (18), fitted in recesses (17) of the intermediate bearing structure, and coupled to the annulus, or ring gear (20) by projecting stubs or pins (21) extending radially into openings (19) formed in the cushions or plugs.

Abstract: This invention relates to a starting motor with planetary gear reduction gears having a spur gear provided at the front end of the rotational shaft of the starting motor, an internal gear secured fixedly to the front end of the yoke of the motor, a planetary gear for engaging the spur gear with the internal gear, an output rotational shaft for transmitting the rotary force of the motor to the planetary gear, and a pair of collars provided on the internal gear at both ends of the teeth of the internal gear.

Abstract: A starting device comprises a cylindrical driving shaft, a rotary output shaft placed contiguous to one end of said driving shaft and extending in alignment therewith, a speed reduction unit for reducing revolution of said driving shaft to transmit power from said driving shaft to said rotary output shaft, and a power transmitting shaft which is firmly connected in alignment with said rotary output shaft and is passed coaxially through said driving shaft so as to be rotatable therein, one end of said power transmitting shaft extending from the other end of said driving shaft.