JP2005240706A - Starter - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a starter preventing transmission of a thrust load to a motor armature 10 when a pinion gear is returned and shortening stopping time from stop of power supply to the motor until inertia rotation of the armature 10 stops. <P>SOLUTION: A partition plate 13 partitions off a motor chamber 25 and a speed reduction chamber 26 and prevents brush powder produced by wear of a brush from entering the speed reduction chamber 26 and forms a thrust receiving member for bearing the thrust load applied to an output shaft 4 by allowing a tip of a support pin 22 supporting a planetary gear 21 to contact with it when the output shaft 4 is returned in a motor direction. At the time when the output shaft 4 is returned in the motor direction and the tip of the support pin 22 contacts with the partition plate 13, a predetermined clearance is ensured between a carrier 23 and an armature shaft 10a and the carrier 23 does not contact with the armature shaft 10a. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to a reduction type starter provided with a planetary gear reduction device that reduces the rotational speed of a motor and transmits it to an output shaft.

Conventionally, as an example of a starter provided with a planetary gear reduction device, there is a known technique described in Patent Document 1.
In this starter, a one-way clutch is arranged between the planetary gear reduction device and the output shaft, and a support pin for supporting the planetary gear is fixed to the clutch outer of the one-way clutch, so that the revolving motion of the planetary gear is directly clutched. It is transmitted to the outer. The rotational force transmitted to the output shaft through the one-way clutch is transmitted from the pinion gear that moves on the output shaft and meshes with the ring gear of the engine to the ring gear to crank the engine.
JP 58-214668 A

  In the above starter, when the pinion gear is returned on the output shaft via the shift lever, the pinion gear collides with a stepped portion provided on the output shaft, so that the impact (thrust load) at the time of the collision is applied to the output shaft. It is transmitted. On the other hand, the amount of the output shaft that can be moved backward is regulated by a gear portion (sun gear that meshes with the planetary gear) provided on the armature shaft of the motor (when the tip portion of the armature shaft is regulated). There is also.) Therefore, when the thrust load is transmitted to the output shaft, the rear end of the output shaft collides with the gear portion, and the thrust load is applied to the armature shaft having the gear portion.

  By the way, a plurality of segments composing the commutator are press-fitted and fixed to the armature shaft of the motor, but the strength of the press-fit portion is lower than that of metal, so the thrust load applied to the armature shaft is press-fitted. When transmitted to the section, there is a risk that the segment may be lifted from the resin material, or in the worst case, the segment may drop off. In particular, the size of the starter has been decreasing in recent years, and the heat capacity of the motor tends to be small. Considering the temperature rise during motor operation, the safety factor of the commutator with respect to the thrust load is reduced, so it has a structure that is resistant to thrust loads. Is required.

  Further, when the energization to the motor is stopped, the frictional resistance generated when the rear end of the output shaft is pressed against the gear portion provided on the armature shaft, and the brush and the commutator pressed by the brush spring are generated. The frictional resistance brakes the inertial rotation of the armature. However, since the rear end of the output shaft pressed against the gear portion has a small diameter, the braking effect due to the frictional resistance between the output shaft and the gear portion is small. On the other hand, as the wear of the brush progresses, the spring force that presses the brush becomes weak, so that the braking force due to the frictional resistance between the brush and the commutator also gradually decreases.

  Therefore, the time until the inertial rotation of the armature stops (stop time) becomes longer as the wear of the brush progresses. If the armature stop time becomes long, the possibility of restarting the starter before the armature completely stops increases due to the driver's carelessness when the engine start is unsuccessful. In this case, since the rotational speed of the pinion gear meshing with the ring gear during inertial rotation increases, the impact force generated when the pinion gear and the ring gear mesh with each other is large, which may damage the starter.

  The present invention was made based on the above circumstances, and its purpose is to prevent the thrust load from being transmitted to the armature of the motor when the pinion gear returns, and after the energization to the motor is stopped, An object of the present invention is to provide a starter that can shorten the stop time until the inertial rotation of the armature stops.

(Invention of Claim 1)
The starter of the present invention is provided immediately before the armature so that the thrust load applied to the output shaft is not transmitted to the armature when the pinion gear moves in the motor direction on the output shaft or in the motor direction integrally with the output shaft. And a thrust receiving member for receiving a thrust load.
According to this configuration, the thrust load is not transmitted to the armature when the pinion gear is returned (when the pinion gear moves in the motor direction on the output shaft or when the pinion gear moves in the motor direction integrally with the output shaft). Therefore, damage to the commutator provided in the armature can be prevented.

(Invention of Claim 2)
2. The starter according to claim 1, wherein the thrust receiving member is a partition plate that partitions between a motor chamber in which an armature is disposed and a reduction chamber in which a reduction gear is disposed, and the planetary gear is provided on the partition plate. Or a support pin that rotatably supports the planetary gear via a gear bearing or a gear bearing abuts against the thrust load.
According to this configuration, since an existing partition plate is used as the thrust receiving member, there is no need to newly install a thrust receiving member, and an increase in cost due to the provision of the thrust receiving member can be avoided.

  Further, since the planetary gear, the support pin, or the gear bearing that comes into contact with the partition plate is located radially outside the gear portion (sun gear with which the planetary gear meshes) provided on the armature shaft, it is disclosed in Patent Document 1. Compared to the starter, the friction radius is increased and the braking force is increased. This braking force does not change much even when the wear of the brush progresses and the reaction force of the brush spring (the urging force that presses the brush against the commutator) decreases, so that the braking performance can be maintained over a long period of time.

(Invention of Claim 3)
The starter according to claim 1, wherein the thrust receiving member includes a partition plate that partitions between the motor chamber in which the armature is disposed and the reduction chamber in which the reduction device is disposed, and a reduction chamber side of the partition plate. A plate member having a surface hardness higher than that of the partition plate is disposed, and a support pin or a gear bearing that rotatably supports the planetary gear via the planetary gear or the gear bearing is brought into contact with the plate member. And receiving a thrust load.
According to the above configuration, the planetary gear, the support pin, or the gear bearing does not directly contact the partition plate, but abuts against the plate member having a higher surface hardness than the partition plate. Reduction can be achieved.

(Invention of Claim 4)
The starter described in claim 3 is characterized in that the plate member engages with a partition plate or a component adjacent to the plate member and is restricted in rotation.
According to this configuration, since the accompanying rotation of the plate member can be prevented, a braking force is obtained by the frictional resistance generated between the plate member and the component (planet gear, support pin, or gear bearing) that comes into contact with the plate member. be able to.
Moreover, since the plate member is arrange | positioned at the deceleration chamber side of a partition plate, a plate member can be stuck on a partition plate with the grease used for a reduction gear device, and a starter with sufficient assembly property can be provided.

(Invention of Claim 5)
The starter according to claim 3 or 4, wherein the plate member is formed using a brake material having a high friction coefficient.
In this case, since the braking force is inevitably increased by using the brake member for the plate member, the armature stop time can be shortened.

(Invention of Claim 6)
The starter according to any one of claims 2 to 4, wherein the component that contacts the thrust receiving member is an oil-impregnated sintered product.
For example, by using parts such as gear bearings and planetary gears as oil-impregnated sintered products, wear of the two can be suppressed when rotating while abutting against the thrust receiving member.

(Invention of Claim 7)
The starter according to any one of claims 2 to 6, wherein the output shaft is provided so as to be movable in the axial direction, and the one-way clutch for transmitting the rotation decelerated by the reduction gear to the output shaft. Is a structure in which a side wall for restricting movement of the roller to the axial motor side is provided integrally with the outer, and a support pin is fixed to the side wall, and a planetary gear, a support pin, or a gear bearing is provided. A predetermined gap is ensured between the tip of the armature shaft and the side wall in a state where the arm is in contact with the partition plate or the plate member.

  According to the starter of the present invention, when the output shaft moves in the motor direction, the rear end of the output shaft collides with the side wall portion of the one-way clutch, so that the thrust load is transmitted from the output shaft to the side wall portion, and further the side wall A support pin fixed to the portion, a gear bearing fitted to the support pin, or a planetary gear fitted to the gear bearing so as to rotate freely abuts against the thrust receiving member (partition plate or plate member), and the thrust receiving member The thrust load can be received. At this time, since a predetermined gap is secured between the tip of the armature shaft and the side wall portion, a thrust load is not transmitted to the armature, and damage to the commutator provided in the armature can be prevented.

(Invention of Claim 8)
8. The starter according to claim 7, wherein a support pin is press-fitted into the side wall, and the side wall has a press-fitting hole for press-fitting the support pin, and a back surface of the side wall through the press-fitting hole. A communication hole penetrating to the (anti-deceleration chamber side surface) is formed, and the inner diameter of the communication hole is smaller than the inner diameter of the press-fitting hole.
When the press-fitted hole is a bottomed hole that does not penetrate the side wall, when the planetary gear pin is press-fitted into the press-fitted hole, the air remaining inside the press-fitted hole is compressed and the press-fitting load varies, so May cause defects. On the other hand, in the present invention, since the press-fitting hole penetrates the side wall portion through the communication hole, the press-fitting load does not vary and the press-fitting failure can be prevented.

However, even when the press-fitting hole penetrates the side wall portion, the following problems occur when straight press-fitting holes having the same inner diameter are formed from the front surface to the back surface of the side wall portion.
When the component that contacts the thrust receiving member is a support pin, when the support pin is pressed into the press-fitting hole while the support pin contacts the thrust receiving member many times, the support pin is in contact with the thrust receiving member, There is a possibility that the clearance secured between the tip of the armature shaft and the side wall portion becomes gradually smaller, and finally the side wall portion comes into contact with the tip of the armature shaft, so that a thrust load is transmitted to the armature.

Furthermore, if the end portion of the support pin pushed into the press-fitting hole is pushed into the outer cam chamber formed on the side of the side wall portion opposite to the deceleration chamber, the one-way clutch may be locked.
On the other hand, in the present invention, a communication hole that passes through the press-fitting hole and penetrates to the back surface of the side wall portion is formed, and the inner diameter of the communication hole is smaller than the inner diameter of the press-fitting hole. The above-mentioned trouble can be prevented without being pushed into the inside.

  The best mode for carrying out the present invention will be described in detail with reference to the following examples.

FIG. 1 is a cross-sectional view of a starter 1 according to the first embodiment.
The starter 1 according to the present embodiment includes a motor 2 that generates a rotational force, a reduction device (described later) that reduces the rotation speed of the motor 2, and rotation that is reduced by the reduction device via a one-way clutch 3. The output shaft 4 to be transmitted, the pinion gear 5 disposed on the output shaft 4, and the main contact (not shown) provided in the energization circuit of the motor 2 are controlled to open and close, and the output shaft is connected via the shift lever 6. 4 includes an electromagnetic switch 7 for moving the shaft 4 in the axial direction.

The motor 2 is a DC motor composed of a field 8 that generates magnetic flux, an armature 10 having a commutator 9, a brush 11 disposed on the commutator 9, and the like. When the closing control is performed, a starting current is supplied from an in-vehicle battery (not shown), and a rotational force is generated in the armature 10.
The field 8 is configured by fixing a field pole 8b to the inner periphery of a yoke 8a forming a magnetic circuit, and winding a field coil 8c around the field pole 8b. A magnetic field may be used instead of the wound field.

The armature 10 includes an armature shaft 10a that is rotatably supported, an armature core 10b that is fixed to the armature shaft 10a, and an armature coil 10c that is wound around the armature core 10b. One end side of the armature shaft 10 a is supported by a partition plate 13 (described later) via a bearing 12, and the other end side is supported by an end frame 15 via a ball bearing 14.
The commutator 9 is configured by arranging a plurality of segments insulated and held through the resin material 16 on the outer periphery of the other end of the armature shaft 10a in a cylindrical shape, and each segment is electrically connected to the armature coil 10c. And mechanically coupled.
As shown in FIG. 1, the brush 11 is disposed on the radially outer side of the commutator 9 and is pressed against the commutator 9 by a brush spring 17.

The reduction gear includes a sun gear 18 formed at the other end of the armature shaft 10 a, a ring-shaped internal gear 20 that is restricted in rotation by the center case 19, and a plurality of planetary gears 21 that mesh with the two gears 18, 20. , And a well-known planetary gear speed reducer comprising a carrier portion 23 that supports the planetary gear 21 via the support pins 22, and reduces the rotational speed of the armature 10 to the revolution speed of the planetary gear 21.
The planetary gear 21 is rotatably supported by a support pin 22 via a gear bearing 24, and the support pin 22 is fixed to the carrier portion 23 by press fitting or the like.

  As shown in FIG. 2, the partition plate 13 partitions the space between the motor chamber 25 in which the armature 10 is disposed and the reduction chamber 26 in which the reduction gear is disposed. The generated brush powder is prevented from entering the deceleration chamber 26. The partition plate 13 has a substantially circular outer diameter portion sandwiched between the yoke 8a of the motor 2 and the center case 19, the inner diameter side is provided in a cylindrical shape, and one end side of the armature shaft 10a on the inner periphery thereof The bearing 12 that supports is press-fitted and fixed.

  Further, the partition plate 13 of the present embodiment is such that the tip of the support pin 22 that supports the planetary gear 21 abuts when the output shaft 4 is returned to the motor direction (right direction in FIG. 1) via the shift lever 6. Thus, the thrust receiving member of the present invention for receiving the thrust load applied to the output shaft 4 is formed. Since the partition plate 13 is slidably contacted in the circumferential direction with the tips of the support pins 22 in contact, heat treatment such as carburizing may be performed to increase the surface hardness of the partition plate 13.

  Here, as shown in FIG. 2, the amount by which the support pin 22 can move in the axial direction with respect to the partition plate 13 (gap between the support pin 22 and the partition plate 13) is A, and the support pin 22 and the partition When the gap A formed between the carrier portion 23 and the armature shaft 10a is B in a state where the gap A is secured between the plate 13 and the board 13, the relationship of A <B is established. As a result, a predetermined gap is secured between the carrier portion 23 and the armature shaft 10a when the tip of the support pin 22 comes into contact with the partition plate 13, so that the carrier portion 23 contacts the armature shaft 10a. There is no contact. Note that a stepped surface formed one step lower than a portion where the support pin 22 is fixed is provided on the end surface of the carrier portion 23 facing the tip of the armature shaft 10a, and the gap B is secured by the stepped surface. Yes.

The center case 19 is disposed between the yoke 8a and the front housing 27 and covers the outside of the reduction gear and the one-way clutch 3.
As shown in FIG. 2, the one-way clutch 3 is formed on an outer 3a provided integrally with the carrier portion 23, a tube 28 forming an inner on the inner diameter side of the outer 3a, and an inner periphery of the outer 3a. A roller 3b or the like disposed in a cam chamber (not shown) is configured, and torque is transmitted from the outer 3a that is a driving side rotating body to the tube 28 that is a driven side rotating body via the roller 3b. The carrier portion 23 is disposed so as to block between the armature shaft 10a and the output shaft 4, and the side wall portion of the present invention that restricts the movement of the roller 3b to the axial motor side (right side in FIG. 2). Also serves as.

As shown in FIG. 2, the tube 28 is provided with a bearing portion 28a on the side opposite to the motor in the axial direction (the left side in the drawing), and is rotatable to the center case 19 via a ball bearing 29 disposed on the outer periphery of the bearing portion 28a. It is supported by.
On the inner periphery of the tube 28, a female helical spline 28b (see FIG. 2) is formed. The female helical spline 28b is formed from one end of the tube 28 to the inner diameter side of the bearing portion 28a, and the terminal (end) of the female helical spline 28b serves as a stopper 28c that stops the axial movement of the output shaft 4 relative to the tube 28. It is functioning.

  The output shaft 4 is disposed coaxially with the armature shaft 10a of the motor 2 via the speed reducer and the one-way clutch 3, and one end side is supported by the front housing 27 via the bearing 30 (see FIG. 1). The other end is inserted into the inner periphery of the tube 28, and the male helical spline 4 a formed on the outer periphery is engaged with the female helical spline 28 b of the tube 28. As a result, the output shaft 4 can be rotated integrally with the tube 28 and can be moved in the axial direction with respect to the tube 28. In FIG. 1, the upper side of the center line of the output shaft 4 indicates the stationary state of the starter 1, and the lower side of the center line indicates the operating state of the starter 1 (the output shaft 4 moves forward and the pinion gear 5 moves to the ring gear of the engine. 31 is engaged).

  The pinion gear 5 is, for example, spline-coupled to the front end portion of the output shaft 4 protruding forward from the bearing 30 so as to be rotatable integrally with the output shaft 4 and disposed between the pinion gear 5 and the output shaft 4. In response to the reaction force of the pinion spring 32, the output shaft 4 is urged in the anti-motor direction (left direction in FIG. 1) and held in contact with the collar 33 attached to the tip of the output shaft 4. ing. The retracted position of the pinion gear 5 with respect to the output shaft 4 is regulated by the total compression amount of the pinion spring 32 when the pinion spring 32 is fully compressed.

  The electromagnetic switch 7 includes an exciting coil 34 that is energized from a battery by closing a start switch (not shown), a plunger 35 that is attracted by the magnetic force generated by the exciting coil 34, and the energization of the exciting coil 34 is stopped. Is formed by a return spring 36 or the like for pushing back the plunger 35, and the main contact is controlled to open and close according to the movement of the plunger 35, and the output shaft 4 is moved in the axial direction via the shift lever 6.

The shift lever 6 is swingably supported by a lever holder 37 fixed to the center case 19, an upper end portion of the lever is connected to a hook 38 held by the plunger 35, and a lower end portion of the lever is provided on the output shaft 4. The pair of washers 39 are engaged to transmit the movement of the plunger 35 to the output shaft 4.
In FIG. 1, the upper side of the center line of the plunger 35 shows the stationary state of the electromagnetic switch 7 (when the excitation coil 34 is deenergized), and the lower side of the center line shows the operating state of the electromagnetic switch 7 (excitation coil 34). Is shown).

Next, the operation of the starter 1 will be described.
When the exciting coil 34 of the electromagnetic switch 7 is energized by the closing operation of the start switch, the plunger 35 is attracted, whereby the output shaft 4 is pushed out in the counter-motor direction via the shift lever 6. Here, when the pinion gear 5 on the output shaft 4 meshes smoothly with the ring gear 31 of the engine, the main contact is closed, and a rotational force is generated in the armature 10.

  Further, when the pinion gear 5 collides with the ring gear 31 without meshing with the ring gear 31, only the output shaft 4 further moves forward while the pinion spring 32 is pressed and contracted, so that the pinion gear 5 relatively moves backward on the output shaft 4. To do. As a result, when the pinion gear 5 rotates to a position where it can mesh with the ring gear 31, the pinion gear 5 is pushed out and meshed with the ring gear 31 by the reaction force of the pinion spring 32, and then the main contact is closed, thereby causing the armature 10 to rotate. Occurs.

When the engagement between the pinion gear 5 and the ring gear 31 is completed, the rotational force is transmitted from the pinion gear 5 to the ring gear 31 to crank the engine.
When the start switch is opened after the engine is started, the magnetic force disappears due to the stop of energization to the exciting coil 34. Therefore, the plunger 35 is pushed back by the reaction force of the return spring 36, and the main contact is opened. Is turned off.

When the plunger 35 is pushed back, the output shaft 4 moves in the motor direction via the shift lever 6, and the rear end of the output shaft 4 collides with the carrier portion 23, so that the carrier portion 23 moves toward the anti-pinion gear side. The tip of the support pin 22 fixed to the carrier part 23 comes into contact with the partition plate 13 by moving.
The motor 2 has a frictional resistance generated between the brush 11 and the commutator 9 and a frictional resistance generated between the support pin 22 and the partition plate 13 when the main contact is opened and the energization of the armature 10 is stopped. Thus, the inertial rotation of the armature 10 is braked and gradually decelerated and stopped.

(Effect of Example 1)
In the starter 1 described in the first embodiment, when the output shaft 4 moves in the motor direction, the tip of the support pin 22 fixed to the carrier portion 23 hits the partition plate 13, so that the output shaft 4 moves to the carrier portion 23. The transmitted thrust load can be received by the partition plate 13. At this time, a predetermined gap is ensured between the tip of the armature shaft 10a and the carrier portion 23 in a state where the tip of the support pin 22 is in contact with the partition plate 13, so that the armature shaft 10a from the carrier portion 23 is secured. Thrust load is not transmitted to As a result, no great stress is applied to the commutator 9 provided in the armature 10, and the commutator 9 can be prevented from being damaged (segment lift, dropout, etc.).

  Further, since the support pin 22 that contacts the partition plate 13 is positioned radially outward from the sun gear 18 provided on the armature shaft 10a, the rear end of the output shaft 4 is applied to the side surface of the sun gear 18 to apply braking force. Since the friction radius becomes larger than when it is generated, a larger braking force can be obtained. This braking force does not change much even if the wear of the brush 11 progresses and the reaction force of the brush spring 17 decreases, so that the braking performance can be maintained over a long period of time.

FIG. 3 is a sectional view showing the reduction gear and its peripheral structure.
As shown in FIG. 3, the starter 1 according to the second embodiment has a plate member 40 disposed on the speed reducing chamber 26 side of the partition plate 13, and the support pin 22 abuts against the plate member 40, so that a thrust load is generated. It is a structure to catch.
The plate member 40 has a surface hardness higher than that of the partition plate 13 and is engaged with the partition plate 13 to be restricted in rotation. According to this configuration, the support pins 22 do not directly contact the partition plate 13 and contact the plate member 40 having a surface hardness higher than that of the partition plate 13, so that the heat treatment for the partition plate 13 can be abolished. As a result, the cost can be reduced by using the partition plate 13 with raw materials.

  In addition, since the plate member 40 is engaged with the partition plate 13 and is restricted in rotation, even if the support pin 22 in contact with the plate member 40 rotates (revolving motion around the armature shaft 10a), The accompanying rotation of the plate member 40 can be prevented, and a braking force can be obtained by the frictional resistance generated between the plate member 40 and the support pin 22. Note that the plate member 40 may be engaged with a component other than the partition plate 13 (for example, the center case 19) to restrict rotation.

Furthermore, since the plate member 40 is arranged on the speed reducing chamber 26 side of the partition plate 13, the plate member 40 can be attached to the partition plate 13 by the grease used for the gear portion of the speed reducer, and the assembly performance is improved. A good starter 1 can be provided.
The plate member 40 of the present embodiment can also use a brake material having a high friction coefficient. In this case, since the braking force inevitably increases, the stop time of the armature 10 can be further shortened.

Further, in the second embodiment, as shown in FIG. 3, a through hole penetrating the carrier portion 23 in the axial direction is formed, and the support pin 22 is press-fitted into the through hole.
The through hole has an inner diameter into which the support pin 22 can be press-fitted, and is recessed from the surface of the carrier portion 23 to a predetermined depth, and from the bottom of the press-fit hole 41 to the back side of the carrier portion 23. The tapered portion 42 gradually decreases in inner diameter, and the small-diameter hole 43 penetrates from the small-diameter side of the tapered portion 42 to the back surface of the carrier portion 23.

  Here, when the press-fitting hole 41 is a bottomed hole that does not penetrate the carrier portion 23, when the support pin 22 is press-fitted into the press-fitting hole 41, the air remaining inside the press-fitting hole 41 is compressed, If the press-fit load varies, press-fit failure may occur. On the other hand, in Example 2, since the press-fitting hole 41 penetrates the carrier part 23 through the tapered part 42 and the small-diameter hole 43, the compressed air is confined in the press-fitting hole 41 when the support pin 22 is press-fitted. The press-fitting failure can be prevented by stabilizing the press-fitting load.

In addition, the press-fit hole 41 is not a straight shape having the same inner diameter from the front surface to the back surface of the carrier portion 23, and a tapered portion 42 is provided on the bottom side of the press-fit hole 41, so that the press-fit depth of the support pin 22 is regulated. it can.
If the press-fitting hole 41 penetrates to the back surface of the carrier part 23 with a straight shape, when the support pin 22 abuts against the partition plate 13 many times and is pushed into the press-fitting hole 41, Since the gap with the support pin 22 is increased, the gap secured between the tip of the armature shaft 10a and the carrier portion 23 is gradually reduced in a state where the support pin 22 is in contact with the partition plate 13, and finally In this case, the carrier portion 23 may come into contact with the tip of the armature shaft 10a and a thrust load may be transmitted to the armature shaft 10a.

Further, when the end portion of the support pin 22 pushed into the press-fitting hole 41 is pushed out to the cam chamber of the outer 3 a formed on the side of the carrier portion 23 opposite to the deceleration chamber, the roller 3 b interferes with the support pin 22. As a result, the one-way clutch 3 may be locked.
On the other hand, in Example 2, since the tapered portion 42 is provided on the bottom side of the press-fit hole 41, the support pin 22 is not pushed beyond the maximum depth of the press-fit hole 41, and the support pin 22 is partitioned. A predetermined gap can be secured between the tip of the armature shaft 10a and the carrier portion 23 in the state of being in contact with the plate 13, and there is no possibility that the roller 3b interferes with the support pin 22. The direction clutch 3 is not locked.

FIG. 4 is a sectional view showing the reduction gear and its peripheral structure.
In the starter 1 according to the third embodiment, as shown in FIG. 4, tapered surfaces 10 d and 23 a that are recessed in a conical shape are formed on the front end surface of the armature shaft 10 a and the end surface of the carrier portion 23 that face each other in the axial direction. The ball 44 is disposed between the tapered surfaces 10d and 23a.
According to this configuration, the outer 3a of the one-way clutch 3 can be centered with respect to the armature shaft 10a via both the tapered surfaces 10d and 23a and the ball 44. That is, at the time of so-called overrun when the engine is completely exploded and the rotation of the engine is transmitted to the pinion gear 5, the roller 3b is lifted from the surface of the tube 28 (inner) by centrifugal force. It becomes a state that can be eccentric in the radial direction. At this time, the eccentricity of the outer 3a is suppressed by the presence of the ball 44 disposed between the both tapered surfaces 10d and 23a.

  Also in the starter 1 according to the third embodiment, when the output shaft 4 is returned in the motor direction, the support pins 22 can contact the partition plate 13 (or the plate member 40) to receive the thrust load. It is possible to prevent the thrust load from being transmitted to the child shaft 10a.

FIG. 5 is an overall view including a partial cross section of the starter 1.
The starter 1 described in the first to third embodiments has a structure in which the pinion gear 5 disposed on the output shaft 4 meshes with the ring gear 31 by the output shaft 4 moving in the axial direction with respect to the tube 28. For example, as shown in FIG. 5, the starter 1 having a structure in which a carrier portion 23 is integrally provided at the rear end of the output shaft 4 and the pinion gear 5 and the one-way clutch 3 move integrally on the output shaft 4. The present invention can also be applied.

(Modification)
In the first to third embodiments, an example in which the support pin 22 is brought into contact with the partition plate 13 or the plate member 40 has been described. However, in addition to the support pin 22, for example, a gear bearing 24 fitted to the support pin 22 or a planetary gear. The thrust load may be received by bringing 21 into contact with the partition plate 13 or the plate member 40.
In addition, by making the parts to be brought into contact with the partition plate 13 or the plate member 40 into an oil-impregnated sintered product (for example, an oilless bearing), when rotating while contacting the partition plate 13 or the plate member 40, Wear can be suppressed.

1 is a cross-sectional view of a starter according to Embodiment 1. FIG. It is an expanded sectional view showing the reduction gear concerning Example 1 and its peripheral structure. It is an expanded sectional view which shows the reduction gear concerning Example 2, and its peripheral structure. It is an expanded sectional view which shows the reduction gear concerning Example 3, and its surrounding structure. It is a general view including the partial cross section of the starter concerning Example 4. FIG.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Starter 2 Motor 3 One-way clutch 3a Outer 3b Roller 4 Output shaft 5 Pinion gear 9 Commutator 10 Armature 10a Armature shaft 13 Partition plate (thrust receiving member)
21 planetary gear 22 support pin 23 carrier part (side wall part)
24 gear bearing 25 motor chamber 26 deceleration chamber 28 tube (inner)
31 Ring gear 40 Plate member 41 Press-fit hole 42 Tapered part (communication hole)
43 Small-diameter hole (communication hole)

Claims (8)

A motor that generates rotational force on an armature having a commutator;
A planetary gear reduction device that reduces the rotational speed of the armature by the revolving motion of the planetary gear;
An output shaft that is arranged on the same axis as the rotation shaft (armature shaft) of the armature through the reduction device, and rotates by transmitting a rotational force directly or indirectly from the reduction device,
A starter having a pinion gear that moves in the direction opposite to the motor on the output shaft or moves in the direction opposite to the motor integrally with the output shaft and meshes with the ring gear of the engine,
When the pinion gear moves in the motor direction on the output shaft or moves in the motor direction integrally with the output shaft, the thrust load applied to the output shaft is not transmitted to the armature immediately before the armature. And a thrust receiving member for receiving the thrust load. The starter according to claim 1,
The thrust receiving member is a partition plate that partitions between a motor chamber in which the armature is disposed and a reduction chamber in which the reduction gear is disposed, and the planetary gear or the gear bearing is provided on the partition plate. And a support pin for rotatably supporting the planetary gear or the gear bearing abuts to receive the thrust load. The starter according to claim 1,
The thrust receiving member is disposed on the speed reduction chamber side of the partition plate, and a partition plate that partitions between a motor chamber in which the armature is disposed and a speed reduction chamber in which the speed reduction device is disposed, A plate member whose surface hardness is higher than that of the partition plate, and a support pin that rotatably supports the planetary gear via the planetary gear or the gear bearing or the gear bearing abuts on the plate member. A starter for receiving the thrust load. The starter according to claim 3,
The plate member is restricted in rotation by engaging with the partition plate or a component adjacent to the plate member. The starter according to claim 3 or 4,
The plate member is formed using a brake material having a high friction coefficient. In any starter according to claims 2-4,
The starter characterized in that the component that contacts the thrust receiving member is an oil-impregnated sintered product. The starter according to any one of claims 2 to 6,
The output shaft is provided to be movable in the axial direction;
The output shaft includes a one-way clutch that transmits rotation decelerated by the speed reducer,
In this one-way clutch, a roller that is a torque transmission member is disposed between an outer that is a driving side rotating body and an inner that is a driven side rotating body, and a side wall that restricts the movement of the roller toward the axial motor side. A portion is provided integrally with the outer, and the support pin is fixed to the side wall portion;
In a state where the planetary gear, the support pin, or the gear bearing is in contact with the partition plate or the plate member, a predetermined gap is secured between the tip of the armature shaft and the side wall portion. A starter characterized by that. The starter according to claim 7,
The support pin is press-fitted to the side wall,
The side wall is formed with a press-fitting hole for press-fitting the support pin, and a communication hole penetrating through the press-fitting hole to the back surface of the side wall (an anti-deceleration chamber side surface). The starter is characterized in that the inner diameter of the presser is smaller than the inner diameter of the press-fitting hole.

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