JP2964731B2 - Starter - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a starter for starting an engine by an electric motor.

[0002]

2. Description of the Related Art In general, a starter has a pinion gear driven by a drive shaft of an electric motor via an overrunning clutch. The pinion gear excites an electromagnetic coil by a switch-on operation when the electric motor is started. The engine is slid in the direction of the rotation center axis of the overrunning clutch and meshed with a ring gear provided on the output shaft of the engine to rotate and start the engine. In a conventional starter, as shown in FIG. 5, the driven side member of the overrunning clutch 80, for example, rotates integrally with a driven side tube 81 and is slidable in the rotation center axis direction of the driven side tube 81. A shaft 82 is concentrically supported by the driven side tube 81, and is formed into a cylindrical wall shape, and a pinion gear 83 is formed coaxially and integrally with an outer peripheral surface of the pinion gear 83. The shaft 85 is slidably supported in the axial direction slidably and non-rotatably through the serrations of the portion 85, and an annular collar 86 is attached to the tip 85 by serration, and a circumferential groove formed in the tip 85 of the shaft 82. A C-shaped clip 89 is engaged with 87 to prevent the collar 86 from falling off, and furthermore, a front end is provided between the shaft 82 and the pinion gear base cylinder portion 84. Color 86 has been provided a spring 88 for urging in a direction to contact with the C-shaped clip 89.

[0003]

According to the structure of the conventional starter described above, since there is a clearance based on serration between the shaft 82 and the collar 86 and between the shaft 82 and the pinion gear base cylinder portion 84, the engine is driven during rotation. When the outside air with high humidity is sucked into the crankcase by the ventilation action in the crankcase due to the reciprocating motion of the piston, and the water vapor in the outside air condenses into water, the water enters the gap and causes rust. As a result, the function of the starter may be impaired. Accordingly, an object of the present invention is to provide a starter that does not rust on the pinion gear base cylinder portion of the starter even when condensation of water vapor that has entered the crankcase occurs.

[0004]

A starter according to the present invention is driven by a drive shaft of an electric motor via an overrunning clutch, and is slid in the direction of the rotation center axis of the overrunning clutch when the electric motor is started. A pinion gear meshed with a ring gear provided on an output shaft of the engine, wherein the pinion gear has a cylindrical peripheral wall, an end wall closing one end of the cylindrical peripheral wall, and the cylindrical peripheral wall. An annular flange formed so as to protrude in the radial direction of the peripheral wall at a position slightly apart from the opening edge at the other end of the cylindrical peripheral wall in the axial direction; and the flange and the opening end. An outer peripheral surface portion for fixing formed on the outer peripheral surface with the cylindrical peripheral wall between the edge and a pinion gear base cylinder portion, which is formed coaxially and integrally with the outer peripheral surface of the cylindrical peripheral wall, Over An engaging portion slidably engaged in the axial direction in the driven side tube of the running clutch by a screw spline, an end engaged on the outer peripheral surface, and an outer periphery between the end and the engaging portion. At least on the surface, a shaft formed with a concave portion forming a step at the edge on the engaging portion side is concentrically inserted and supported, and the pinion gear base cylinder portion is configured to connect the cylindrical peripheral wall to the shaft. It is concentrically engaged with the outer peripheral surface of the end portion, and is fixed to the inner peripheral edge portion engaging with the ridge of the shaft and the outer peripheral fixing portion formed on the cylindrical peripheral wall at the opening edge of the cylindrical peripheral wall. The shaft is supported by a combination collar having a cylindrical portion having an inner peripheral surface portion for fixing between the flange portion of the pinion gear base cylinder portion and the edge of the cylindrical wall portion of the combination collar. , An annular elastic member made of an elastic material Between the pinion gear cylindrical base portion and the shaft, characterized in that said combined color 突畝 forming said pinion gear cylindrical base portion to said shaft was urged to spring in a direction to be engaged.

[0005]

The overdrive clutch is driven from the drive shaft of the electric motor via an overrunning clutch, and slides and rotates in the direction of the rotation axis of the overrunning clutch when the electric motor is started, and meshes with a ring gear provided on the output shaft of the engine. In a starter provided with a pinion gear to be rotated, generally, rotation is transmitted to a pinion gear from a driving shaft of an electric motor via a driving side member of an overrunning clutch and a driven side member of the overrunning clutch. The pinion gear is moved in the direction of the rotation center axis of the overrunning clutch by using the excitation of the electromagnetic coils arranged side by side, and meshes with the ring gear provided on the output shaft of the engine. At this time, in the present invention, the shaft is engaged with the driven tube of the overrunning clutch by a screw spline so as to be slidable in the center axis direction of the driven tube by the engaging portion thereof. The driven tube is slid in the central axis direction while slightly rotating about the central axis. Due to this sliding,
The pinion gear engaged with the outer peripheral surface of the end of the shaft by the pinion gear base cylinder so as not to rotate relatively is also advanced, and the end surface of the pinion gear collides with the end surface of the ring gear provided on the output shaft of the engine. I do.

If the end face of the pinion gear collides with the end face of the ring gear and the two teeth cannot mesh immediately, the tooth of the ring gear at the position where the tooth of the pinion gear collides,
The pinion gear is rotated relative to the ring gear until the tooth meshes with the next adjacent tooth, during which a spring disposed between the shaft and the pinion gear base cylinder by forward sliding of the shaft. Is bent, and when the pinion gear and the ring gear mesh properly, the pinion gear base cylinder slides in the center axis direction with respect to the shaft due to the elastic force stored in the spring, and the pinion gear and the ring gear Is completed, whereby the ring gear is rotated by the electric motor to drive the engine. When the engine starts, the rotation speed of the engine exceeds the rotation speed of the electric motor of the starter. At this time, the overrunning clutch idles so as not to drive the electric motor from the engine side, and when the rotation of the electric motor of the starter is stopped, the shaft returns to the original position, so that the pinion gear is brought into mesh with the ring gear. It is released. Engagement by the thread spline between the shaft and the driven tube of the overrunning clutch assists in meshing and releasing between the ring gear and the pinion gear. A pinion gear base cylinder portion in which a pinion gear is integrally formed on the outer peripheral surface of the cylindrical peripheral wall, one end of the cylindrical peripheral wall portion is closed by an end wall, and the cylindrical peripheral wall is formed on the outer peripheral surface of the end portion of the front shaft. Coaxially, slidably in the direction of the rotation center axis of the shaft and non-rotatably connected around the rotation center axis, the pinion gear meshes with or disengages from the ring gear. At this time, the collision between the pinion gear and the ring gear is reduced together with the spring, and the rotation of the pinion gear is reliably transmitted to the ring gear. An axial end of the pinion gear base cylinder is closed by an end wall, and an annular elastic material made of an elastic material is provided between the flange of the pinion gear base cylinder and the end of the cylindrical end of the combination collar. Since the member is clamped, water is prevented from entering into a gap between the pinion base cylinder and the shaft when the pinion gear base cylinder slides relative to the shaft in the direction of the rotation center axis.

[0007]

FIG. 1 is a partially cutaway side view of an overrunning clutch portion according to a first embodiment of the present invention, and FIGS. In the figure, a roller and a spring 4 are interposed between a gear ring 2 corresponding to an outer ring and a tube 3 corresponding to an inner ring of the overrunning clutch 1, and the gear ring 2 has a cold outer circumferential surface. The tube 3 is driven when a driving force is transmitted to a gear 5 integrally formed by forging or the like by a drive shaft of an electric motor (not shown), and the tube 3 as a driven member is driven at a higher speed than the gear ring 2 as a driving member. Overrunning of the gearing 2 is allowed when rotating at. The tube 3 is mounted on a starter housing (not shown) at the outer peripheral surfaces of both ends in the axial direction.
The shaft 8 is rotatably supported by the shaft 7, and the shaft 8 is slidably supported coaxially with the rotation center axis in a shaft hole formed about the rotation center axis. In the shaft hole of the tube 3, a screw spline 12 is engraved on the inner wall at one end near the electric motor, and the screw spline 12 for loosely fitting the shaft 8 is formed on the inner wall at the other end. A loose fitting surface 10 having an inner diameter smaller than the inner diameter of the tooth tip portion is formed, and a tip portion and a root portion of the screw spline 12 extend from an end of the loose fitting surface 10 to a formation portion of the screw spline 12. Are formed on the enlarged inner wall surface having an intermediate diameter of the inner diameter of the inner surface of the inner surface of the inner surface of the housing, and a step portion 15 is formed at a boundary between the enlarged inner wall surface and the loose fitting surface 10.

The shaft 8 is formed integrally with a screw spline 9 which engages with a screw spline 12 formed on the tube 3 on an outer peripheral surface of an end 11 on a side close to the electric motor. The outer peripheral surface of the portion accommodated in the shaft hole portion is slightly smaller than the outer diameter of the root portion of the screw spline 9, and has an outer diameter that is slidably and loosely fitted to the loose fitting surface 10 of the tube 3. The loose fitting portion 14 is formed. A return spring 13 made of a helical spring is inserted into the shaft hole of the tube 3, one end of which is a step 15 formed on the inner wall of the tube 3, and the other end of which is a step formed with the screw spline 9 of the shaft 8. The portions 16 are respectively in contact with the step portions formed at the boundary with the loose fitting portion 14 to urge the shaft in the direction of approaching the electric motor. The shaft 8
A small-diameter portion 17 connected to the loose fitting portion 14 and having an outer diameter smaller than the outer diameter of the loose fitting portion 14 is formed coaxially for a predetermined length in the axial direction. In the center portion of the shaft, a protruding ridge 18 having the same outer diameter as the outer diameter of the loose fitting portion 14 is formed annularly in the circumferential direction coaxially with the shaft 8. The protruding ridges 18 are formed from the outer peripheral walls at both ends in the axial direction.
A wall surface reaching the outer peripheral surface of the shaft 7 is formed as a wall surface perpendicular to the rotation center axis of the shaft 8. At the other end of the shaft 8, an end 19 having the same outer diameter as the outer diameter of the loose fitting portion 14 is formed coaxially with the small diameter portion 17. Serrations 20 are formed parallel to the rotation center axis 8. The shaft 8 has both ends 1
1, 19, the loose fitting portion 14, and the ridge 18 are formed coaxially, so that the screw spline 9 and the serration 20 can be formed simultaneously by rolling.

The pinion gear base cylinder portion 21 has a cylindrical peripheral wall 27.
And one end of the peripheral wall 27 is connected to the pinion gear base cylinder 21.
And has a cup-like shape formed at the open end opening at the other end of the cylindrical peripheral wall 27, and the shaft 8 is provided on the inner wall of the cylindrical peripheral wall 27. A serration 23 that fits with the serration 20 is formed, and a large-diameter inner wall portion is formed in which the inner diameter of the inner wall is enlarged from the end on the opening edge side of the serration 23 to the opening edge. A step 25 for engaging a pinion spring 24 described later is formed at the boundary with the serration 23. In addition, the pinion gear base cylinder portion 21
A pinion gear 26 is integrally formed on the outer peripheral surface of the cylindrical peripheral wall 27 by cold forging or the like, and is located at a position slightly axially separated from the outer peripheral surface of the cylindrical peripheral wall 27 by a short distance from the opening edge. The annular flange portion 44 formed by projecting in the radial direction of the cylindrical peripheral wall 27 is
And the flange portion 4
4 from the outer peripheral surface to the opening edge of the cylindrical peripheral wall 27,
One protruding ridge 28 is formed on a fixing outer peripheral surface portion 29 protruding annularly in the circumferential direction. The pinion gear base cylinder portion 21 has a serration 23 formed on the inner peripheral surface of the cylindrical peripheral wall 27.
Is engaged with the serrations 20 formed at the end 19 of the shaft 8 and is mounted on the outer peripheral surface of the end, and is mounted on the shaft 8 by the combination of the first and second collars 30 and 31. As shown in FIG. 2, the first collar 30 has a semi-cylindrical arc-shaped wall portion 33 that covers a circumferential half of the fixing outer peripheral surface portion 29 of the cylindrical peripheral wall 27 of the pinion gear base cylinder portion 21. A semi-annular engaging wall portion 35 extending inward in the radial direction from one edge of the wall portion 33 is provided on an inner peripheral surface of the arc-shaped wall portion 33. Groove 32 that engages with a ridge 28 protruding from
The radius of the inner peripheral edge 34 of the engagement wall portion 35 is equal to or slightly larger than the outer diameter of the small diameter portion 17 of the shaft 8, and the ridge 18 The dimension is sufficiently smaller than the outer diameter of. On the outer peripheral surface of the fixing outer peripheral surface portion 29 of the pinion gear base cylindrical portion 21, two first collars 30 are engaged with the grooves 32 of the arc-shaped wall portion 33 and the protrusions 28, respectively. The joint wall portion 35 is disposed in contact with the opening edge of the cylindrical peripheral wall 27.

[0010] The second collar 31 is the first collar 3
A cylindrical peripheral wall portion 37 that covers the outer peripheral wall of the 0 arcuate wall portion 33
And an annular flange 38 radially inward from one side edge of the peripheral wall portion 37. The radius of the inner peripheral edge 36 of the flange 38 is slightly larger than the outer diameter of the loose fitting portion 14 of the shaft 8. The radius of the inner peripheral surface 39 of the peripheral wall portion 37 is a dimension fixed by press-fitting to the arc-shaped wall portion 33 of the first collar 30, and the two first collars 30 are fixed.
Are disposed on the fixing outer peripheral surface of the pinion gear base cylinder portion 21 and then the second collar 31 is pressed until the flange 38 of the second collar 31 contacts the engaging wall portion 35 of the first collar 30. Of the first collar 30 and the second collar 3 are pressed into the outer peripheral surface of the arc-shaped wall 33 of the first collar 30.
1 constitutes a combination collar fixed to the pinion gear base cylinder 21. The engagement wall portion 35 of the first collar 30 constituting the combination collar is disposed at a position corresponding to the small diameter portion 17 between the ridge 18 of the shaft 8 and the loose fitting portion 14. On the other hand, a stopper 40 that engages with the pinion spring 24 is provided in the small diameter portion 17 between the ridge 18 and the end portion 19 of the shaft 8. The stopper 40 has an inner diameter sized to be slidable on the outer peripheral surface of the small-diameter portion 17, and an outer diameter of a large-diameter inner wall portion formed on the inner peripheral surface of the cylindrical peripheral wall 27 of the pinion gear base cylinder portion 21. In addition to the pinion spring 24, which is a helical spring composed of two semi-annular stopper members sized to be slidable on the peripheral surface and having one end engaged with the boundary between the large-diameter inner wall portion and the serration forming portion. Engaged at the end. The stopper 40 is connected to the pinion spring 2
The pinion gear base cylinder portion 21 is pressed against the wall surface on the end portion 19 side of the ridge 18 of the shaft 8 by the elasticity of the shaft 4, and the engaging wall portion 35 of the first collar 30 is formed by the elasticity of the pinion spring 24. Is urged in a direction to engage a step formed on the wall of the shaft 8 on the side of the loose fitting portion 14 of the ridge 18. An annular groove 4 is formed on the wall surface of the flange portion 44 facing the free edge of the peripheral wall portion 37 of the second collar 31.
5, the annular seal member 46 made of a flexible elastic member is fitted and held. The second collar 31 is the first
The second collar 31 when pressed into the second collar 31
The free edge of the peripheral wall portion 37 is tightly engaged with the seal member 46 to achieve liquid tightness between the flange portion 44 and the second collar 31.

A return spring 13 is mounted on the loose fitting portion 14 of the shaft 8 and the shaft 8 is inserted into the shaft hole of the tube 3 from the end of the tube 3 where the screw spline 12 is formed. End 19, ridges 18, and loose fits 14
Is smaller in diameter than the loose fitting surface 10 of the tube 3, and when the screw spline 9 of the shaft 8 is engaged with the screw spline 12 of the tube 3, the end 19 and the small diameter portion 17 protrude from the other end of the tube 3. You. The second collar 31 is inserted into the shaft 8. Since the inner peripheral edge 36 of the second collar 31 has a size slightly larger than the serration 20 of the shaft 8 and the outer diameter of the ridge 18, it can pass through the end 19 and the ridge 18. Two stoppers 40 for engaging the pinion spring 24 are annularly mounted on a wall surface of the shaft 8 perpendicular to the rotation center axis on the end portion 19 side of the ridge 18. Here, the pinion gear base cylinder portion 21 containing the pinion spring 24 is slid in the axial direction while the serrations 23 formed on the inner wall of the cylindrical peripheral wall 27 are fitted to the serrations 20 of the shaft 8, and the projections 18 are formed.
Of the two first collars 30 on a step formed by a wall surface perpendicular to the rotation center axis on the side of the loose fitting portion 14.
5 are brought into contact with each other, and a groove 32 engraved on the inner peripheral surface of the arc-shaped wall portion 33 is engaged with a ridge 28 protruding from the fixing outer peripheral surface portion 29 of the cylindrical peripheral wall 27. The second collar 31 inserted earlier is press-fitted and fixed to the outer peripheral surface of the arcuate wall 33 of the collar 30 in the direction of the pinion gear base cylinder 21 in the axial direction. By the above assembling work, the pinion spring and the step 25 of the pinion gear base cylinder 21 and the stopper 4
0, the return spring 13 is elastically provided between the step 15 of the tube 3 and the step 16 of the shaft 8. The forward position of the pinion gear 26 is restricted by the loose fitting portion 14 between the engaging wall portion 35 of the first collar 30 and the ridge 18 of the shaft 8.
It can be determined at a position where it comes into contact with the side wall surface. Further, the pinion spring 25 is sufficiently extended to
The engaging wall portion 35 of the collar 30 has the loose fitting portion 1 of the ridge 18.
In a state in which it is in contact with the wall surface of the stepped portion on the side of the fourth side, the shaft 8 is formed between the end surface of the tip portion 19 of the shaft 8 and the inner surface of the end wall 22 of the pinion gear base tube portion 21 in the central axis direction of the shaft 8. The dimension L ₁ of the gap is the dimension L ₂ of the gap between the end face of the engagement wall of the first collar 30 on the tube 3 side and the boundary between the small diameter portion 17 of the shaft 8 and the loose fitting portion 14. The size of the pinion spring 24 is equal to or smaller than that of the pinion spring 24 and does not hinder the expansion and contraction of the pinion spring 24.

In this embodiment, when the starter switch is opened, the shaft 8 is biased by a return spring 13 toward a magnet switch (not shown) provided to the electric motor (right side in FIG. 1). However, when the starter switch is closed, the coil of the magnet switch is excited, and the end 11 provided with the threaded spline of the shaft 8 is pushed through a ball by a known method, and the shaft 8 is connected to the tube of the overrunning clutch 1. 3 along the central axis of FIG. 1 and at the same time, the rotational driving force of the motor
Is transmitted to the gear 5 formed on the gear ring 2. As a result, the tube 3, which is the driven member of the overrunning clutch 1, is also driven to rotate, and the screw spline 9 formed on the shaft 8 and the screw spline 12 formed on the tube 3 are rotated.
, And rotates in the axial direction while compressing the return spring 13 in the tube 3 and is pushed toward the ring gear (the left side in FIG. 1). The pinion gear base cylinder 21 is also pushed out in the axial direction while rotating integrally with the shaft 8 via serrations 23 engaging with the serrations 20 on the outer peripheral surface of the end portion 19 of the shaft 8, and the pinion gear 26 is connected to the ring gear. Mesh with each other. The pinion spring 24 softens the impact when the end face of the pinion gear 26 collides with the end face of the ring gear. When the end face of the pinion gear 26 collides with the end face of the ring gear and the two do not engage immediately, the pinion spring 24 is compressed, and the pinion gear base cylinder 21 is formed on the inner peripheral wall of the cylindrical peripheral wall 27. The engagement between the serrations 23 and the serrations 20 formed at the end 19 of the shaft 8 causes the pinion gear 2 to slide in the axial direction of the shaft 8.
When the teeth of No. 6 mesh with the teeth of the ring gear, the elasticity stored in the pinion spring 24 is applied to the sliding of the pinion gear 26 into the link gear. Pinion gear 2
When 6 meshes with the ring gear, the engine is started by the rotational driving force of the electric motor. When the engine starts, the engine rotation speed becomes higher than the rotation speed of the pinion gear base cylinder portion 21, so that the tube 3 of the overrunning clutch 1 idles with respect to the gear ring 5 so that the electric motor is not driven from the engine side. When the starter switch is opened, the attractive force of the coil of the magnet switch disappears and the shaft 8
Is returned to the magnet switch side by the elastic force of the return spring 13 provided in the tube 3, and the pinion gear base cylinder portion 21 is engaged with the step formed by the ridge 18 of the shaft 8 and the engagement wall of the first collar 30. When the pinion gear 26 and the ring gear are disengaged from each other, the pinion gear 26 and the ring gear are disengaged from each other.

When the motor of the starter is stationary,
The second collar 31 and the tube 3 are always in contact with each other, and the free edge of the peripheral wall 37 of the second collar 31 is
Since it is closely engaged with the seal member 46 held by the shaft 4, the intrusion of water from the outside into the pinion gear base cylinder 21 at the tip of the shaft 8 can be completely prevented.
Even if the seal member 46 made of an elastic member mounted in the groove 45 formed in the flange portion 44 of the pinion gear base cylinder portion 21 repeats minute movement in the axial direction due to an impact when the ring gear and the pinion gear 26 are engaged by the starter operation. The elasticity of the seal member 46 can prevent wear of the engaging portion between the protrusion 28 formed on the fixing outer peripheral surface portion 29 of the pinion gear base cylinder portion 21 and the groove 32 of the first collar 30.

FIG. 4 is a partially cut-away view of the configuration of the combination collar and the means for mounting the collar on the pinion gear base cylinder according to the second embodiment different from the first embodiment shown in FIG. Shown in cutaway side view. Therefore, in this embodiment, the same parts as those in the first embodiment are denoted by the same reference numerals, and the description thereof will be omitted. A male thread 61 is formed on the fixing outer peripheral surface portion 29 of the cylindrical peripheral wall 27 of the pinion gear base cylinder portion 21 instead of the single annular ridge 28 in the first embodiment. The first collar 32 has a semi-annular shape made of a plate-like material, and the radius of the outer peripheral edge thereof is slightly smaller than the radius of the root of the male thread 61 formed on the fixing outer peripheral surface portion 29. The radius of the inner peripheral edge is the small diameter portion 1 of the shaft 8.
7 is equal to or slightly larger than the outer diameter of the ridge 18 and sufficiently smaller than the outer diameter of the ridge 18.
The second collar 63 is provided on the inner peripheral surface with the fixing outer peripheral surface portion 29.
A cylindrical peripheral wall formed with a female thread meshing with the male thread 61 formed in the above, and an annular flange directed radially inward from one side edge of the peripheral wall are formed. The radius is slightly larger than the outer diameter of the loose fitting portion 14 of the shaft 8. The two first collars 62 are annularly abutted on the opening edges of the cylindrical peripheral wall 27 provided with the fixing outer peripheral surface 29, and the peripheral wall of the second collar 63 is screwed into the male screw of the fixing outer peripheral surface 29. The thread 61 is screwed. First collar 62
Of the female thread formed on the peripheral wall of the second collar 63 is slightly smaller than the inner diameter of the tooth tip of the female thread. The free edge of the peripheral wall portion of the second collar 63 is pressed against the opening edge of the cylindrical peripheral wall 27 and the annular groove 4 formed in the flange portion 44 of the pinion gear base cylinder portion 21.
5 is tightly engaged with the annular sealing member 46 supported
Keep watertight. When tightening the second collar 63, it is necessary to form the peripheral wall portion in a polygonal shape to facilitate the tightening, or to deform a part of the peripheral wall portion by external force after the tightening to ensure the fixing. It is performed according to. The first and second collars 30 and 31 forming the combination color in the first embodiment, and the first and second collars 62 and 63 forming the combination color in the second embodiment.
Is preferably formed of a metal, but a molded product of a synthetic resin can be used as long as the holding power of the combination color is secured.

[0015]

According to the present invention, the pinion gear base cylindrical portion closes one end of the cylindrical peripheral wall integrally formed with the pinion gear, and the outer peripheral surface of the open edge at the other end of the cylindrical peripheral wall. The combination collar is disposed so as to cover the fixing outer peripheral surface portion formed at the free end edge of the cylindrical peripheral wall portion extending on the fixing outer peripheral surface portion of the combination collar and the flange portion of the pinion gear base cylinder portion. Between the pinion gear base cylinder portion of the starter and the base cylinder portion through a serration, a gap between the shaft and the shaft connected to rotate integrally with each other through a serration. It prevents water from entering, prevents rust on the pinion gear base cylinder and the shaft, and prevents poor sliding due to rust between the pinion gear base cylinder and the shaft and rust on the pinion spring. In addition, even if the pinion gear repeatedly repeats minute movement in the axial direction due to the impact caused by the gear meshing when the starter is started, the elastic member serves as a cushioning material, so that the pinion gear base cylinder is fixed by the minute movement. Micro vibrations applied to the connecting portion between the outer peripheral surface portion and the combination collar can be absorbed, and wear between them can be prevented. In the present invention, the pinion gear base cylinder is engaged with the outer peripheral surface of the shaft so as to be slidable in the central axis direction and relatively non-rotatable. Between the end of the shaft and the engaging portion of the shaft that engages the threaded spline of the driven tube of the overrunning clutch, a recess is formed at least at the edge on the engaging portion side to form a step. The combination collar has an inner peripheral edge engaged with the step of the concave portion and a fixing inner peripheral edge fixed to the fixing outer peripheral surface formed on the cylindrical peripheral wall of the pinion gear base cylinder. When the pinion gear immediately meshes with the ring gear when the end face of the pinion gear collides with the end face of the ring gear, the relative sliding of the pinion gear base cylinder in the direction of the center axis of the shaft is provided. Motion and when the shaft is retracted after the engine has started,
The inner peripheral edge of the combination collar engages the step of the shaft to facilitate disengagement of the pinion gear from the ring gear. Further, the shaft is engaged with the driven side tube of the overrunning clutch by screw spline engagement,
Since the pinion gear base cylinder portion is engaged with the shaft by serration engagement, the driving force of the starter motor is reliably transmitted to the pinion gear.

[Brief description of the drawings]

FIG. 1 is a partially cutaway side view of an overrunning clutch according to a first embodiment of the present invention.

FIG. 2 is a perspective view of a first collar.

FIG. 3 is a perspective view of a second collar.

FIG. 4 is a partially cutaway side view of an overrunning portion in a second embodiment of the present invention.

FIG. 5 is a partially cutaway side view of an overrunning portion in a conventional starter.

[Explanation of symbols]

 REFERENCE SIGNS LIST 1 overrunning clutch 2 gearing 3 tube 5 gear 8 shaft 9, 12 screw spline 10 loose fitting surface 11, 19 end 13 return spring 14 loose fitting 17 small diameter portion 18 ridge 20, 23 serration 21 pinion gear base cylinder Reference Signs List 22 End wall 24 Pinion spring 25 Engaging step 26 Pinion gear 27 Cylindrical peripheral wall 28 Flange 29 Fixing outer peripheral surface 30, 62 First collar 31, 63 Second collar 40 Stopper 46 Seal member

──────────────────────────────────────────────────続 き Continued on front page (58) Field surveyed (Int.Cl. ⁶ , DB name) F02N 11/00 F02N 15/02

Claims (1)

(57) [Claims] 1. A ring gear provided on an output shaft of an engine, which is driven from a drive shaft of an electric motor via an overrunning clutch, and is slid in a direction of a rotation center axis of the overrunning clutch when the electric motor is started. In a starter provided with a pinion gear to be meshed, the pinion gear has a cylindrical peripheral wall, an end wall that closes one end of the cylindrical peripheral wall, and the opening peripheral edge at the other end of the cylindrical peripheral wall, which is slightly apart from the opening edge. An annular flange portion formed by projecting in the radial direction of the peripheral wall at a position separated in the axial direction of the cylindrical peripheral wall, and formed on the outer peripheral surface of the cylindrical peripheral wall between the flange portion and the opening edge; A driven side tube of the overrunning clutch, which is formed coaxially and integrally with the outer peripheral surface of the cylindrical peripheral wall of the pinion gear base cylindrical portion having the fixed outer peripheral surface portion; It is,
An engaging portion engaged by a screw spline so as to be slidable in the axial direction of the driven side tube by a predetermined distance, and slidable in the center axis direction on the inner wall surface of the cylindrical peripheral wall of the pinion gear base cylinder portion. An end portion engaging with the outer peripheral surface so as to be relatively non-rotatable, and a concave portion forming a step at least at an edge on the engaging portion side at an outer peripheral surface between the end portion and the engaging portion. The main portion of the engaging portion is concentrically inserted into and supported by the driven side tube, and the pinion gear base cylindrical portion has the cylindrical peripheral wall concentric with the outer peripheral surface of the end portion of the shaft. And fixed to the opening edge of the cylindrical peripheral wall, the inner peripheral edge engaging with the step of the concave portion formed in the shaft, and the fixing outer peripheral surface formed in the cylindrical peripheral wall. The combination collar comprising a cylindrical portion having an inner peripheral edge portion for fixing, An annular elastic member made of an elastic material is sandwiched between a flange of the pinion gear base and a free edge of the cylindrical peripheral wall of the combined collar; A starter characterized in that a spring is urged between a portion and the shaft in a direction in which the combination collar engages a ridge formed on the shaft with the pinion gear base cylinder portion.