JPH0571449A - Starter - Google Patents

Abstract

PURPOSE:To check water immersion between a base cylinder portion where a pinion gear is solidly formed and a shaft for driving the pinion gear so as to prevent rusting in an engine starter for automobile. CONSTITUTION:One end of a pinion gear base cylinder portion 21 is closed by an end wall 22, a combination collar comprising the first and second collars 30, 31 is installed in a fixing outer peripheral surface portion 29 on the open end side and an engaging wall portion of the first collar 30 is engaged with a projecting portion 18 of a shaft 8 to clamp a seal member 46 comprising an elastic member fitted in a recess groove 45 of a flange portion 44 of the pinion gear base cylinder portion with the end edge of the peripheral wall portion of the second collar 31. Accordingly, one end of the pinion gear base cylinder portion 21 is closed, and the other side is closed by the combination collars 30, 31 and the seal member to check water from entering the interior of the pinion gear base cylinder portion 21, so that rusting of the shaft 8 and a pinion spring 24 can be prevented.

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 with an electric motor.

[0002]

2. Description of the Related Art A starter is generally provided with a pinion gear that is driven by a drive shaft of an electric motor through an overrunning clutch, and the pinion gear excites an electromagnetic coil by a switch-on operation when the electric motor is started. By utilizing this, 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 the conventional starter, as shown in FIG. 5, the starter is integrally rotatable with the driven side member of the overrunning clutch 80, for example, the 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 a pinion gear base cylinder portion 84 formed in a cylindrical wall shape and coaxially and integrally forming a pinion gear 83 on an outer peripheral surface of the shaft 82 is attached to the tip of the shaft 82. An axial collar 86 is slidably and non-rotatably supported in the axial direction through the serration of the portion 85, and an annular collar 86 is attached to the distal end portion 85 by serration, and a circumferential groove formed in the distal end portion 85 of the shaft 82. A C-shaped clip 89 is engaged with 87 to prevent the collar 86 from falling off, and further, 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 between the shaft 82 and the collar 86 and between the shaft 82 and the pinion gear base cylinder portion 84 due to serration, the engine is driven and rotated. In addition, when the reciprocating motion of the piston causes ventilation in the crankcase, high-humidity outside air is sucked into the crankcase, and when water vapor in the outside air condenses into water, the water enters the gap and causes rusting. As a result, the function of the starter was impaired. Therefore, it is an object of the present invention to provide a starter that does not rust on the pinion gear base cylinder portion of the starter even if the water vapor that has entered the crankcase is condensed.

[0004]

A starter according to the present invention is driven by a drive shaft of an electric motor through an overrunning clutch, and is slid in a direction of a rotation center axis of the overrunning clutch when the electric motor is started, A pinion gear that meshes with a ring gear provided on an output shaft of an engine, wherein the pinion gear includes a cylindrical peripheral wall, an end wall closing one end of the cylindrical peripheral wall, and the cylindrical peripheral wall. An annular flange portion formed so as to project in the radial direction of the peripheral wall portion at a position slightly separated from the opening edge of the other end of the cylindrical peripheral wall in the axial direction, and the flange portion and the opening end. The pinion gear base cylinder part having a fixing outer peripheral surface part formed on the outer peripheral surface of the cylindrical peripheral wall between the edge and the edge is formed coaxially and integrally with the outer peripheral surface of the cylindrical peripheral wall, Over An engaging portion that engages with a screw spline slidably in the driven side tube of the locking clutch, an end portion that engages with an outer peripheral surface, and an outer circumference between the end portion and the engaging portion. A shaft having at least a concave portion forming a step at the end on the engaging portion side is concentrically inserted and supported on the surface, and the pinion gear base tubular portion has the cylindrical peripheral wall of the shaft. It is concentrically engaged with the outer peripheral surface of the end portion, and is fixed to an opening end edge of the cylindrical peripheral wall, an inner peripheral edge portion engaging with the ridge of the shaft, and an outer peripheral surface portion for fixation formed on the cylindrical peripheral wall. And a cylindrical portion having a fixing inner peripheral surface portion for supporting the shaft on the shaft, and between the flange portion of the pinion gear base cylinder portion and the end edge portion of the cylindrical wall portion of the combination collar. , Hold the annular elastic member made of 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 drive shaft of the electric motor is driven through the overrunning clutch, and when the electric motor is started, it slides and rotates in the direction of the center axis of rotation of the overrunning clutch and meshes with the ring gear provided on the output shaft of the engine. In a starter provided with a pinion gear that is made to rotate, rotation is generally transmitted from a drive shaft of an electric motor to a pinion gear via a driving side member of an overrunning clutch and a driven side member of an overrunning clutch, and the electric motor is 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 in parallel with each other, and is engaged 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 side tube of the overrunning clutch by the screw spline so that the shaft is slidable in the central axis direction of the driven side tube by the engaging portion thereof. The driven tube is slid in the central axis direction while slightly rotating around the central axis. By this sliding,
The pinion gear, which is engaged with the outer peripheral surface of the end portion of the shaft by the pinion gear base tubular portion so as not to be relatively rotatable, 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. To do.

When the end face of the pinion gear collides with the end face of the ring gear and the teeth of the two cannot immediately mesh with each other, the teeth of the ring gear at the position where the teeth of the pinion gear collide,
The pinion gear is rotated with respect to the ring gear until the tooth meshes with the next adjacent tooth, and the spring disposed between the shaft and the pinion gear base cylinder portion by the forward sliding of the shaft in the meantime. When the pinion gear and the ring gear are properly meshed with each other, the elastic force stored in the spring causes the pinion gear base cylinder part to slide in the direction of the central axis with respect to the shaft, and thus the pinion gear and the ring gear. Is completed, and thereby the ring gear is rotated by the electric motor to drive the engine. When the engine starts, the rotational speed of the engine exceeds the rotational speed of the starter motor. 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 engagement with the ring gear. It will be canceled. The threaded spline engagement between the shaft and the driven side tube of the overrunning clutch assists in engagement and disengagement between the ring gear and pinion gear. The pinion gear base cylinder part integrally forming the pinion gear on the outer peripheral surface of the cylindrical peripheral wall is closed at one end of the cylindrical peripheral wall part by an end wall, and the cylindrical peripheral wall is formed on the outer peripheral surface of the end part of the front shaft. The pinion gear meshes with the ring gear or disengages from the gear because it is coaxially connected to the shaft so as to be slidable in the direction of the rotation center axis and not rotatable relative to the rotation center axis. At this time, the collision between the pinion gear and the ring gear is alleviated together with the spring, and the rotation of the pinion gear is reliably transmitted to the ring gear. The axial end of the pinion gear base cylinder is closed by an end wall, and an annular elastic member made of an elastic material is provided between the flange of the pinion gear base cylinder and the end edge of the cylindrical end of the combination collar. Since the members are clamped, water is prevented from entering the gap between the pinion base cylinder part and the shaft when the shaft of the pinion gear base cylinder part is relatively slid in the rotation center axis direction.

[0007]

1 is a partial cutaway side view of an overrunning clutch portion of a first embodiment of the present invention, and FIG. 2 and FIG. 3 are perspective views of the combination collars thereof. In the figure, an overrunning clutch 1 has rollers and springs 4 interposed between a gear ring 2 corresponding to its outer ring and a tube 3 corresponding to its inner ring, and the gear ring 2 is cold-rolled on its outer peripheral surface. When the driving force of a motor (not shown) is transmitted to the gear 5 integrally formed by forging or the like, the tube 3 is driven, and the tube 3 as the driven side member is faster than the gear ring 2 as the driving side member. Allows the gear ring 2 to overrun when rotated at. The tube 3 has bearings 6, 6 on a starter housing (not shown) on the outer peripheral surfaces of both ends in the axial direction.
A shaft 8 is rotatably supported by 7, and a shaft 8 is slidably supported coaxially with the rotation center axis in a shaft hole formed around the rotation center axis. In the shaft hole of the tube 3, a screw spline 12 is engraved on the inner wall of one end on the side close to the electric motor, and on the inner wall of the other end of the screw spline 12 for loosely fitting the shaft 8. A loose fitting surface 10 having an inner diameter smaller than the inner diameter of the tooth tip portion is formed, and a tooth tip portion and a tooth root portion of the screw spline 12 are provided between an end portion of the loose fitting surface 10 and a portion where the screw spline 12 is formed. It is formed on an enlarged inner wall surface having an inner diameter in the middle of the inner diameter, and a step portion 15 is formed on the boundary between the enlarged inner wall surface and the loose fitting surface 10.

A screw spline 9 that engages with a screw spline 12 formed on the tube 3 is integrally formed on the outer peripheral surface of an end portion 11 of the shaft 8 which is 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 tooth root portion of the screw spline 9 and is an outer diameter slidably 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 spiral spring is inserted in the axial 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 is a step where the screw spline 9 of the shaft 8 is formed. The portions 16 are respectively brought into contact with the stepped 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
Has 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 coaxially with a predetermined length in the axial direction. A ridge 18 having an outer diameter that is the same as the outer diameter of the loose fitting portion 14 is coaxially formed with the shaft 8 and is annularly formed in the circumferential direction. The ridge 18 is formed from the outer peripheral wall of both axial end edges thereof to the small diameter portion 1
The wall surface reaching the outer peripheral surface of 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 coaxially formed so as to be connected to the small diameter portion 17, and the shaft 19 is provided on the outer peripheral surface thereof. The serrations 20 are formed parallel to the central axis of rotation of 8. This shaft 8 has both ends 1
Since 1, 19, the loose fitting portion 14, and the ridge 18 are formed coaxially, the thread spline 9 and the serration 20 can be molded at the same time 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 portion 21.
Has a cup-like shape which is closed by an end wall 22 perpendicular to the central axis of the cylindrical peripheral wall 27 and is formed at the opening edge of the other end of the cylindrical peripheral wall 27, and the shaft 8 is formed 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 by enlarging the inner diameter of the inner wall from the end portion on the opening end side of the serration 23 to the opening end edge. A step portion 25 for engaging a pinion spring 24 described later is formed at a boundary portion with the serration 23. In addition, the pinion gear base cylinder portion 21
A pinion gear 26 is integrally projectingly 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 separated from the opening edge in the axial direction of the outer peripheral surface of the cylindrical peripheral wall 27. The annular flange portion 44 formed by projecting in the radial direction of the cylindrical peripheral wall 27 is provided with the pinion gear 26.
The flange portion 4 is formed continuously with the end portion of the
4, the outer peripheral surface from the opening edge of the cylindrical peripheral wall 27 to
A single ridge 28 is formed on an outer peripheral surface portion 29 for fixing which is annularly projected in the circumferential direction. The pinion gear base cylinder portion 21 has serrations 23 formed on the inner peripheral surface of a cylindrical peripheral wall 27 thereof.
Is engaged with the serration 20 formed on the end 19 of the shaft 8 to be attached to the outer peripheral surface of the end, and is attached to the shaft 8 by the combination collar composed of the first and second collars 30 and 31. As shown in FIG. 2, the first collar 30 includes a semi-cylindrical arc-shaped wall portion 33 that covers a circumferential half of the fixing outer circumferential surface portion 29 of the cylindrical peripheral wall 27 of the pinion gear base tubular portion 21, and the arc-shaped wall portion 33. The wall 33 has a semi-annular engagement wall 35 that extends inward from one end edge of the wall 33. The inner peripheral surface of the arc-shaped wall 33 has an outer peripheral surface 29 for fixing the pinion gear base cylinder 21. Groove 32 that engages with the ridge 28 that is provided on the
Are engraved in the circumferential direction, and 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 size 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 tubular portion 21, the two first collars 30 are engaged with the groove 32 of the arcuate wall portion 33 and the ridge 28, and the engagement thereof. The mating wall portion 35 is disposed so as to abut against the opening edge of the cylindrical peripheral wall 27.

The second color 31 is the first color 3
A cylindrical peripheral wall portion 37 that covers the outer peripheral wall of the arc-shaped wall portion 33 of 0.
And an annular flange 38 that extends radially inward from one side edge of the peripheral wall portion 37, and 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. And the radius of the inner peripheral surface 39 of the peripheral wall portion 37 is fixed to the arcuate wall portion 33 of the first collar 30 by press fitting, and the two first collars 30.
Is disposed on the fixing outer peripheral surface portion of the pinion gear base tubular portion 21, and then the second collar 31 until the flange 38 of the second collar 31 comes into contact with the engaging wall portion 35 of the first collar 30. The peripheral wall portion 37 of the first collar 30 is press-fitted onto the outer peripheral surface of the arcuate wall portion 33 of the first collar 30, and the first collar 30 and the second collar 3
1 and 1 constitute a combination collar fixed to the pinion gear base cylinder portion 21. The engaging wall portion 35 of the first collar 30 that constitutes this 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 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 tubular portion 21. Other than the pinion spring 24, which is a spiral spring, which is composed of two semi-annular stopper members and has one end engaged with the boundary portion between the large-diameter inner wall portion and the serration forming portion, and has a size slidable on the peripheral surface. The end is engaged. The stopper 40 is the pinion spring 2
4 is pressed against the wall surface of the shaft 8 on the side of the end portion 19 of the ridge 18, and the pinion gear base cylinder portion 21 is urged by the elasticity of the pinion spring 24 to engage the engagement wall portion 35 of the first collar 30. Is urged in a direction to engage with the step portion formed on the wall surface of the shaft 8 on the loose fitting portion 14 side of the ridge 18. An annular groove 4 is formed on the wall surface of the flange portion 44 facing the free end 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
Second collar 31 when pressed into the collar 30 of
The free end 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 axial hole portion of the tube 3 from the end portion of the tube 3 where the screw spline 12 is formed. End portion 19, ridge 18, and loose fitting portion 14
Has a smaller diameter than the loose fitting surface 10 of the tube 3, so that when the screw spline 9 of the shaft 8 is engaged with the screw spline 12 of the tube 3, the end portion 19 and the small diameter portion 17 are projected to the other end of the tube 3. It 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 serrations 20 of the shaft 8 and the outer diameter of the ribs 18, it can pass through the end portion 19 and the ribs 18. Two stoppers 40 for engaging the pinion spring 24 are annularly mounted on the wall surface of the shaft 8 on the end 19 side of the ridge 18 which is perpendicular to the central axis of rotation. Here, the pinion gear base cylindrical portion 21 accommodating the pinion spring 24 is slid in the axial direction while fitting the serration 23 formed on the inner wall of the cylindrical peripheral wall 27 to the serration 20 of the shaft 8 to slide the ridge 18
Of the engaging wall portions 3 of the two first collars 30 on the step portion formed by the wall surface perpendicular to the rotation center axis on the side of the loose fitting portion 14 of
In a state in which the end face of 5 is brought into contact and the groove 32 formed in the inner peripheral surface of the arc-shaped wall portion 33 is engaged with the ridge 28 formed to project on the fixing outer peripheral surface portion 29 of the cylindrical peripheral wall 27, The previously inserted second collar 31 is press-fitted and fixed to the outer peripheral surface of the arcuate wall portion 33 of the collar 30 in the axial direction toward the pinion gear base tubular portion 21. As a result of the above assembling work, the pinion spring is fixed to the step portion 25 of the pinion gear base cylinder portion 21 and the stopper 4.
Between 0 and 0, the return spring 13 is elastically provided between the step portion 15 of the tube 3 and the step portion 16 of the shaft 8. The forward movement position of the pinion gear 26 is regulated by the loose fitting portion 14 in the engaging wall portion 35 of the first collar 30 and the ridge 18 of the shaft 8.
It can be determined at the position where it abuts against the side wall surface. In addition, the pinion spring 25 is fully extended so that the first
The engaging wall portion 35 of the collar 30 of FIG.
Formed in the central axis direction of the shaft 8 between the end surface of the tip end portion 19 of the shaft 8 and the inner surface of the end wall 22 of the pinion gear base tubular portion 21 in a state of being in contact with the wall surface of the step portion on the fourth side. The dimension L ₁ of the clearance is the dimension L ₂ of the clearance between the end surface of the engagement wall portion of the first collar 30 on the tube 3 side and the boundary portion between the small diameter portion 17 of the shaft 8 and the loose fitting portion 14. The dimension is the same as or smaller than that, and does not hinder the expansion and contraction of the pinion spring 24.

In the present embodiment, when the starter switch is opened, the shaft 8 is urged by the return spring 13 to the side of the magnet switch (not shown) attached to the electric motor (right side in FIG. 1). However, when the starter switch is closed, the coil of the magnet switch is excited, the end portion 11 of the shaft 8 provided with the thread spline is pushed through the ball by a known method, and the shaft 8 becomes a tube of the overrunning clutch 1. 1 is slid to the left in FIG. 1 along the central axis of the motor 3, and at the same time, the rotational driving force of the electric motor is applied to the overrunning clutch 1.
It is transmitted to the gear 5 formed on the gear ring 2. As a result, the tube 3 which is the driven side member of the overrunning clutch 1 is also rotationally driven, and the screw spline 9 formed on the shaft 8 and the screw spline 12 formed on the tube 3 are driven.
It rotates together with the tube 3 through the engagement with and also slides in the tube 3 in the axial direction while compressing the return spring 13 and is pushed out in the direction of the ring gear (left side in FIG. 1). The pinion gear base cylinder part 21 is also pushed out in the axial direction while rotating integrally with the shaft 8 via the serrations 23 engaging with the serrations 20 on the outer peripheral surface of the end part 19 of the shaft 8, and the pinion gear 26 becomes a ring gear. Mesh with each other. The pinion spring 24 softens the impact when the end surface of the pinion gear 26 collides with the end surface of the ring gear. When the end surface of the pinion gear 26 collides with the end surface of the ring gear and the two are not meshed with each other immediately, the pinion spring 24 is compressed and the pinion gear base cylinder portion 21 is formed on the inner peripheral wall of the cylindrical peripheral wall 27 thereof. The engagement between the serrations 23 and the serrations 20 formed on the end 19 of the shaft 8 causes the pinion gear 2 to slide in the axial direction of the shaft 8.
The elastic force stored in the pinion spring 24 when the teeth of 6 and the teeth of the ring gear mesh with each other is added to the sliding of the pinion gear 26 with respect to 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 is started, the engine speed becomes higher than the 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 attraction force of the magnet switch coil is lost and the shaft 8
Is returned to the magnet switch side by the elasticity of the return spring 13 provided in the tube 3, and the pinion gear base cylinder portion 21 is a step portion formed by the ridges 18 of the shaft 8 and the engagement wall of the first collar 30. The engagement with the portion 35 causes the shaft 8 to move along with the shaft 8, and the engagement between the pinion gear 26 and the ring gear is released.

In the stationary state of the starter motor,
The second collar 31 and the tube 3 are always in contact with each other, and the free end edge of the peripheral wall portion 37 of the second collar 31 is the flange portion 4.
Since it tightly engages with the seal member 46 held by 4, it is possible to completely prevent intrusion of water from the outside into the pinion gear base tubular portion 21 at the tip portion of the shaft 8.
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 tubular portion 21 is repeatedly moved in the axial direction by an impact when the ring gear and the pinion gear 26 are meshed by the starter operation. By the elasticity of the seal member 46, it is possible to prevent wear of the engagement portion between the protrusion 28 formed on the fixing outer peripheral surface portion 29 of the pinion gear base tubular portion 21 and the groove 32 of the first collar 30.

FIG. 4 shows a part of the overrunning clutch part of the second embodiment different from the first embodiment shown in FIG. 1 in the structure of the combination collar and the mounting means of the collar to the pinion gear base cylinder part.截 Shown in side view. Therefore, in this embodiment, the same parts as those in the first embodiment are designated by the same reference numerals and the description thereof will be omitted. On the fixing outer peripheral surface portion 29 of the cylindrical peripheral wall 27 of the pinion gear base tubular portion 21, a male thread 61 is formed in place of the one annular projecting ridge 28 in the first embodiment. The first collar 32 has a semi-annular shape made of a plate-shaped material, and the radius of the outer peripheral edge thereof is set to be slightly smaller than the radius of the root portion of the male screw 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 is sufficiently smaller than the outer diameter of the ridge 18.
The second collar 63 has the fixing outer peripheral surface portion 29 on the inner peripheral surface.
A cylindrical peripheral wall portion formed with a female screw thread that meshes with the male screw thread 61 formed in the above, and an annular flange extending inward in the radial direction from one side edge of the peripheral wall portion. The radius is set to be slightly larger than the outer diameter of the loose fitting portion 14 of the shaft 8. The two first collars 62 are annularly abutted against the opening edge of the cylindrical peripheral wall 27 having the fixing outer peripheral surface portion 29, and the peripheral wall portion of the second collar 63 is externally threaded on the fixing outer peripheral surface portion 29. Thread onto the thread 61. First collar 62
Since the radius of the outer peripheral edge of the second collar 63 is slightly smaller than the inner diameter of the tooth tip of the female thread formed on the peripheral wall portion of the second collar 63, the second collar 63 uses the flange to fix the first collar 61. The free end edge of the peripheral wall portion of the second collar 63 is brought into pressure contact with the opening end edge of the cylindrical peripheral wall 27, and the annular concave groove 4 formed in the flange portion 44 of the pinion gear base cylinder portion 21.
5, which is tightly engaged with the annular seal member 46 which is supported by 5,
Keep watertight. When tightening the second collar 63, it is necessary to form the peripheral wall portion into a polygonal shape to facilitate the tightening, or to deform the peripheral wall portion by external force after the tightening to ensure the fixing. 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 made of metal, but a synthetic resin molded product may be used if the holding power of the combination collar is secured.

[0015]

According to the present invention, the pinion gear base cylinder portion closes one end of the cylindrical peripheral wall integrally formed with the pinion gear to the end wall, and the outer peripheral surface of the opening edge at the other end of the cylindrical peripheral wall. A combination collar is formed so as to cover the fixing outer peripheral surface portion formed on the base, and a free end edge of a cylindrical peripheral wall portion extending on the fixing outer peripheral surface portion of the combination collar and a flange portion of the pinion gear base cylinder portion. By sandwiching the annular elastic member between the pinion gear base tubular portion and the base tubular portion of the starter, a gap between the pinion gear base tubular portion and the shaft connected so as to rotate integrally through serrations from the outside is provided. It is possible to prevent water from entering and prevent rusting of the pinion gear base cylinder part and shaft, thereby preventing sliding failure due to rusting between the pinion gear base cylinder part and the shaft and further rusting of the pinion spring. Further, even if the pinion gear repeats minute movements in the axial direction due to the impact of gear meshing that occurs when the starter is started, the elastic member acts as a cushioning material, so the pinion gear base cylinder is fixed by the minute movements. It is possible to absorb the minute vibration applied to the joint portion between the outer peripheral surface portion and the combination collar and prevent the wear between the both. 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 non-rotatable. Between the end portion of the shaft and the engaging portion of the shaft that engages with the screw spline of the driven-side tube of the overrunning clutch, a concave portion that forms a step is formed at least at the end edge on the engaging portion side. The combination collar has an inner peripheral edge portion that engages with the stepped portion of the recess and an inner peripheral edge portion for fixing that is fixed to an outer peripheral surface portion for fixing formed on the cylindrical peripheral wall of the pinion gear base tubular portion. Since the pinion gear engages with the ring gear immediately when the end surface of the pinion gear collides with the end surface of the ring gear, the cylindrical portion of the pinion gear base tubular portion is relatively slid in the axial direction of the shaft. Motion, and when the shaft is retracted after the engine is started,
An inner peripheral edge portion of the combination collar engages with a step portion 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 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 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 according to 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]

 1 Overrunning Clutch 2 Gear Ring 3 Tube 5 Gear 8 Shaft 9, 12 Screw Spline 10 Free Fitting Surface 11, 19 End 13 Return Spring 14 Free Fitting 17 Small Diameter Part 18 Projection Ridge 20,23 Serration 21 Pinion Gear Base Tube 22 End Wall 24 Pinion Spring 25 Engagement Step 26 Pinion Gear 27 Cylindrical Peripheral Wall 28 Flange 29 External Peripheral Surface for Fixing 30,62 First Collar 31,63 Second Collar 40 Stopper 46 Sealing Member

Claims (1)

[Claims] 1. A ring gear provided on an output shaft of an engine, driven by a drive shaft of an electric motor through an overrunning clutch, and slid in a direction of a rotation center axis of the overrunning clutch when the electric motor is started. In a starter including a pinion gear that is meshed with the pinion gear, the pinion gear includes a cylindrical peripheral wall, an end wall that closes one end of the cylindrical peripheral wall, and a slight distance from an opening edge of the other end of the cylindrical peripheral wall. An annular flange portion formed at a position axially separated from the cylindrical peripheral wall so as to project in the radial direction of the peripheral wall, and formed on the outer peripheral surface of the cylindrical peripheral wall between the flange portion and the opening edge. A pinion gear base tubular portion having a fixed outer peripheral surface portion formed coaxially and integrally with the outer peripheral surface of the cylindrical peripheral wall, and the driven side tube of the overrunning clutch. It is,
An engaging portion that engages with a screw spline so as to be slidable in the axial direction of the driven side tube and an inner wall surface of the cylindrical peripheral wall of the pinion gear base tubular portion are slidable in the central axis direction thereof. And an end portion that engages with the outer peripheral surface so as not to be relatively rotatable, and a concave portion that forms a step portion at least at the end edge on the engaging portion side on the outer peripheral surface between the end portion and the engaging portion. The shaft, the main part of the engaging part is concentrically inserted and supported in the driven side tube, and the pinion gear base cylinder part has the cylindrical peripheral wall concentric with the outer peripheral surface of the end part of the shaft. Are fixed to the inner peripheral edge portion that engages with the step portion of the recess formed in the shaft and the fixing outer peripheral surface portion formed in the cylindrical peripheral wall portion at the opening end edge of the cylindrical peripheral wall. With a combination collar comprising a cylindrical portion having an inner peripheral edge portion for fixing, The pinion gear base cylinder is supported by a shaft, and an annular elastic member made of an elastic material is sandwiched between a flange portion of the pinion gear base cylinder portion and a free end edge of the cylindrical peripheral wall portion of the combination collar. A starter characterized in that a spring is urged between the portion and the shaft in a direction in which the combination collar engages with a ridge formed on the shaft of the pinion gear base tubular portion.