JP2009002237A - Starter - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a starter capable of suppressing run out of a clutch outer 14 and of reducing the total length. <P>SOLUTION: A clutch outer 14 is provided as one unit with a carrier part 13 outputting revolution motion of a planetary gear 12, and is provided with an outer regulation part 17 at a center part of the carrier part 13. A round hole 17a is formed at a radial direction center part of the outer regulation part 17, and an end part (tip part) of an anti-commutator side of an armature shaft 9 inserted through the same. The tip part of the armature shaft 9 passes through the round hole 17a of the outer regulation part 17 and is inserted inside of hollow hole 15b formed on a clutch inner 15, and is relatively rotatably supported by the clutch inner 15 via an armature bearing 22 press-fitted and fixed on an inner circumference of the hollow hole 15b. Consequently, run out of the armature shaft 9 can be suppressed and run out of the clutch outer 14 can be regulated in a range where an one way clutch 5 can smoothly transmit torque. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a starter for starting an engine.

As a prior art, there is a starter described in Patent Document 1.
As shown in FIG. 5, the starter includes a speed reducer that reduces the rotational speed of the armature 100 and a one-way clutch that transmits the rotation reduced by the speed reducer to the output shaft 110.
In the armature 100, one end of the armature shaft 120 that outputs rotational force (the end on the counter-reduction gear side) is supported by an end frame (not shown) via a bearing, and the other end of the armature shaft 120 is a bearing. The dust-proof plate 140 is supported via 130.
The speed reducer includes a sun gear 150 provided on the armature shaft 120, an internal gear 160 disposed concentrically with the sun gear 150, a plurality of planetary gears 170 meshing with both gears 150 and 160, and the planetary gears. It is a planetary gear reducer composed of a carrier 180 or the like that takes out the revolution movement of 170.

The one-way clutch is provided integrally with the carrier 180, and is a clutch inner 200 provided integrally with the output shaft 110 and a clutch outer 200 that is supported on the tip of the armature shaft 120 via a bearing 190 so as to be relatively rotatable. 210 and a plurality of rollers 220 arranged between the two 200 and 210.
According to the above configuration, the vibration of the clutch outer 200 caused by the rotation of the armature 100 can be suppressed, and even when the clutch outer 200 is unbalanced, torque transmission of the one-way clutch can be performed smoothly.
Japanese Patent Laying-Open No. 2005-130753

However, in the starter described above, the bearing 130 is disposed on the other end side of the armature shaft 120 (on the side opposite to the clutch of the sun gear 150) to suppress the swing of the armature 100. In this case, since it is necessary to secure a space for disposing the bearing 130 between the armature 100 and the speed reducer, there is a problem that the total length of the starter becomes long.
The present invention has been made based on the above circumstances, and an object of the present invention is to provide a starter capable of suppressing the shake of the clutch outer and shortening the overall length.

(Invention of Claim 1)
The present invention relates to a motor that generates rotational force and a planetary gear reducer that reduces the rotational speed of the armature shaft by revolving around the sun gear provided on the armature shaft of the motor while the planetary gear rotates. And a clutch outer and a clutch inner provided so as to be relatively rotatable, a wedge-shaped cam chamber is formed between the two and a roller accommodated in the cam chamber, and the torque amplified by the speed reducer The clutch outer is provided integrally with a carrier for taking out the revolving motion of the planetary gear and has an outer restriction having a round hole at the radial center of the carrier. The clutch inner is rotatably supported by the housing via an inner bearing, and a hollow hole is formed in the central portion in the radial direction. The end portion on the tip side from the portion where the sun gear is provided passes through the round hole of the outer restricting portion and is inserted into the hollow hole, and is connected to the clutch inner via the armature bearing disposed on the inner periphery of the hollow hole. It is supported so as to be relatively rotatable.

According to said structure, the edge part of the armature shaft is supported via the armature bearing by the clutch inner supported by the housing via the inner bearing. That is, the clutch inner is centered on the housing via the inner bearing, and the end of the armature shaft is supported by the clutch inner via the armature bearing, so that the swing of the armature shaft can be suppressed.
In addition, by disposing the armature bearing on the inner periphery of the hollow hole formed in the clutch inner, it is not necessary to dispose the armature bearing on the anti-clutch side of the sun gear, thereby shortening the total length of the starter. Is possible.
Further, by passing the end portion of the armature shaft through the round hole of the outer restricting portion provided in the center portion of the carrier, the armature shaft can suppress the shake of the clutch outer.

(Invention of Claim 2)
2. The starter according to claim 1, wherein a difference in size between the inner diameter of the outer restricting portion and the outer diameter of the armature shaft passing through the round hole is 2a, on the inner peripheral side or the outer peripheral side of the armature bearing. When the clearance is 2b, and the maximum separation amount that the roller can separate from the outer peripheral surface of the clutch inner during the overrun of the one-way clutch (lift) is c,
c> a + b …………………… (1)
The relationship of the above formula (1) is established.
Thereby, the swing of the clutch outer can be suppressed when the one-way clutch is overrun. That is, the clutch outer can be centered and regulated within a range where smooth torque transmission of the one-way clutch can be performed.
The bearing clearance 2b is a dimensional difference between the inner diameter of the armature bearing and the outer diameter of the armature shaft when the armature bearing is press-fitted into the inner periphery of the hollow hole. Is press-fit into the outer diameter of the armature bearing and the inner diameter of the hollow hole.

(Invention of Claim 3)
The starter according to claim 1 or 2, wherein d is a maximum eccentric amount of the clutch outer that occurs when two rollers adjacent in the circumferential direction bite into a narrow space of the cam chamber.
a + b> d …………………… (2)
The relationship of the above formula (2) is established.
In this case, when the roller bites into the narrow space of the cam chamber, the outer restricting portion does not become a harmful effect, so that it is possible to prevent the two rollers from being locked while the clutch outer is eccentric. That is, since the operation of the one-way clutch is not hindered by the outer restricting portion, smooth torque transmission can be performed.

(Invention of Claim 4)
The starter according to any one of claims 1 to 3, wherein the clutch outer has a through hole formed in a central portion in a radial direction of the carrier, and an outer regulating portion having a ring shape is fitted to an inner periphery of the through hole. It is characterized by that.
In this case, the outer restricting portion can be provided separately from the clutch outer, and the outer restricting portion can be formed of a material different from that of the clutch outer.

  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 the starter 1.
The starter 1 of the present embodiment includes a motor that generates a rotational force in the armature 2, a speed reducer 3 that reduces the rotational speed of the motor, and a rotation that is decelerated by the speed reducer 3 and transmits the rotation to the output shaft 4. The direction clutch 5, the pinion gear 6 supported by the output shaft 4, and the main contact (not shown) provided in the motor energization circuit are opened and closed, and the pinion gear 6 is moved in the axial direction via the shift lever 7. The electromagnetic switch 8 having
The motor is, for example, a known commutator motor having a commutator (not shown) on one end side (counter reducer side) of the armature shaft 9.

The speed reducer 3 is a planetary gear speed reducer that can be decelerated coaxially with the armature shaft 9, and as shown in FIG. 2, a sun gear 10 provided on the side of the armature shaft 9 opposite to the commutator, and the sun gear 10 And a plurality of planetary gears 12 meshing with both gears 10, 11, a carrier portion 13 for taking out the revolving motion of the planetary gears 12, and the like.
As shown in FIG. 2, the one-way clutch 5 includes a clutch outer 14 provided integrally with the carrier portion 13, a clutch inner 15 provided integrally with the output shaft 4, and a plurality of members that intermittently transmit torque between them. It is composed of individual rollers 16 and the like.

  The clutch outer 14 is provided with an outer restricting portion 17 at the center of the carrier portion 13, and radial deflection is suppressed by the outer restricting portion 17. As shown in FIG. 2, the outer restricting portion 17 is formed with a round hole 17a in the central portion in the radial direction, and the tip of the armature shaft 9 is inserted into the round hole 17a. Further, a plurality of wedge-shaped cam chambers 14b (see FIG. 3) are formed in the circumferential direction between the inner periphery of the clutch outer 14 and the outer peripheral surface of the clutch inner 15, and the rollers 16 are accommodated in the cam chamber 14b. Has been. The roller 16 is biased by the spring 18 in the narrowing direction of the cam chamber 14b.

  The clutch inner 15 has an inner shaft portion 15a whose outer diameter is smaller than that of the inner outer peripheral surface that contacts the roller 16 during torque transmission. The inner shaft portion 15a is provided integrally with the output shaft 4, and the inner shaft portion 15a It is rotatably supported by the center housing 20 via an inner bearing 19 fitted to the outer periphery. The center housing 20 is fixed to the inner periphery of a front housing 21 attached to the engine so as not to rotate. Further, as shown in FIG. 2, the clutch inner 15 is provided with a hollow hole 15b at the center in the radial direction, and an armature bearing that supports the tip of the armature shaft 9 on the inner periphery of the hollow hole 15b. 22 is press-fitted and fixed. That is, the armature shaft 9 is inserted into the inner periphery of the hollow hole 15b through the round hole 17a of the outer restricting portion 17 at the opposite end of the commutator side, and is relative to the clutch inner 15 via the armature bearing 22. It is supported rotatably. Note that the end of the armature shaft 9 on the commutator side is rotatably supported by an end frame (not shown) via a bearing.

Here, conditions for suppressing the swing of the clutch outer 14 will be described with reference to FIGS. 2 and 3.
The dimensional difference between the inner diameter of the round hole 17a of the outer restricting portion 17 and the outer diameter of the armature shaft 9 passing through the round hole 17a is 2a. The dimensional difference between the inner diameter of the armature bearing 22 and the outer diameter of the armature shaft 9 (Bearing clearance) is 2b, the maximum separation amount that the roller 16 can separate from the outer peripheral surface of the clutch inner 15 when the one-way clutch 5 is overrun is c, and the two rollers 16 adjacent in the circumferential direction are in the narrow space of the cam chamber 14b. If the maximum amount of eccentricity of the clutch outer 14 that occurs when biting in is d,
c> a + b …………………… (1)
a + b> d …………………… (2)
The relationship of said (1) and (2) Formula is materialized.

Next, the operation of the starter 1 will be described.
When an electromagnetic coil (not shown) built in the electromagnetic switch 8 is energized to form an electromagnet by closing the start switch (not shown), the plunger 23 (see FIG. 1) is attracted to the electromagnet. As a result, the pinion gear 6 is pushed out on the output shaft 4 in the counter-motor direction (left direction in FIG. 1) via the shift lever 7. When the main contact is closed by the movement of the plunger 23, the motor is energized from the battery, and a rotational force is generated in the armature 2. When the rotation speed of the armature 2 is decelerated by the speed reducer 3 and transmitted to the output shaft 4 via the one-way clutch 5, the motor from the pinion gear 6 meshed with the ring gear (not shown) of the engine is transferred to the ring gear. Drive torque is transmitted to crank the engine.

When the engine is started from cranking and the start switch is opened, the energization to the electromagnetic coil is stopped and the attractive force of the electromagnet disappears, so that the plunger 23 is moved by the reaction force of the return spring (not shown). Pushed back. As a result, the main contact is opened, energization from the battery to the motor is stopped, and the rotation of the armature 2 is gradually decelerated and stopped.
Further, when the plunger 23 is pushed back, the shift lever 7 swings in the direction opposite to that when starting the engine, so that the pinion gear 6 is disengaged from the ring gear, and then on the output shaft 4 at a predetermined position (position shown in FIG. 1). Step back to stop.

(Effect of Example)
In the starter of this embodiment, the clutch inner 15 is centered on the center housing 20 via the inner bearing 19, and the tip end portion of the armature shaft 9 is supported on the clutch inner 15 via the armature bearing 22. The swing of the armature shaft 9 can be suppressed. Further, by disposing the armature bearing 22 on the inner periphery of the hollow hole 15b formed in the clutch inner 15, it is not necessary to secure a space for disposing the armature bearing 22 on the side opposite to the clutch of the sun gear 10, The total length of the starter can be shortened.
Furthermore, when the relationship of the above formulas (1) and (2) is established, the centering of the clutch outer 14 can be restricted within a range in which the torque can be transmitted smoothly from the one-way clutch 5.

That is, by satisfying the condition of the expression (1), the swing of the clutch outer 14 can be suppressed at the time of overrun when the rotational speed of the clutch inner 15 exceeds the rotational speed of the clutch outer 14.
Further, by satisfying the condition of the expression (2), when the roller 16 bites into the narrow space of the cam chamber 14b, the outer restricting portion 17 does not become a harmful effect. It is possible to prevent the roller 16 from being locked. That is, since the operation of the one-way clutch 5 is not hindered by the outer restricting portion 17, smooth torque transmission can be performed.

FIG. 4 is a cross-sectional view showing a main part of the starter 1.
The present embodiment is an example in which the outer restricting portion 17 is configured as a separate member from the carrier portion 13 of the clutch outer 14.
As shown in FIG. 4, the clutch outer 14 has a through hole formed in the center portion in the radial direction of the carrier portion 13, and a ring-shaped outer restricting portion 17 is fitted to the inner periphery of the through hole.
According to this configuration, the outer restricting portion 17 can be formed of a material different from that of the clutch outer 14.

(Modification)
In the starters shown in the first and second embodiments, the output shaft 4 does not move with respect to the one-way clutch 5, and the pinion gear 6 moves alone on the outer periphery of the output shaft 4. The present invention can also be applied to a starter configured such that the output shaft 4 and the pinion gear 6 move integrally with respect to the direction clutch 5. For example, the inner shaft portion 15a of the clutch inner 15 may be provided in a cylindrical shape, and the output shaft 4 may be inserted into the inner periphery of the clutch inner 15 so that the two are helical spline fitted.

(Example 1) which is sectional drawing of a starter. (Example 1) which is an expanded sectional view of a one-way clutch part. It is sectional drawing which shows the cam chamber of a one-way clutch. (Example 2) which is sectional drawing of a starter. It is sectional drawing of the starter which concerns on a prior art.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Starter 3 Reduction gear 4 Output shaft 5 One-way clutch 9 Armature shaft 10 Sun gear 12 Planetary gear 13 Carrier part 14 Clutch outer 14b Cam chamber 15 Clutch inner 15b Hollow hole 16 Roller 17 Outer restriction part 17a Round hole of outer restriction part 19 Inner bearing 20 Center housing (housing)
22 Armature bearing

Claims (4)

A motor that generates rotational force;
A planetary gear reducer that reduces the rotational speed of the armature shaft by revolving around the sun gear provided on the armature shaft of the motor while rotating around the planetary gear;
It has a clutch outer and a clutch inner provided so as to be capable of relative rotation, and a wedge-shaped cam chamber is formed between the two and a roller accommodated in the cam chamber, and the torque amplified by the speed reducer can be obtained. A starter comprising a one-way clutch for transmitting to an output shaft,
The clutch outer is provided integrally with a carrier for taking out the revolving motion of the planetary gear, and an outer restricting portion having a round hole in the radial center portion of the carrier is provided.
The clutch inner is rotatably supported by the housing via an inner bearing, and a hollow hole is formed in a central portion in the radial direction.
The armature shaft has an end on the tip side from a portion where the sun gear is provided, passes through the round hole of the outer restricting portion, is inserted into the hollow hole, and is disposed on the inner periphery of the hollow hole. A starter which is supported by the clutch inner via an armature bearing so as to be relatively rotatable. The starter according to claim 1,
2a, the dimensional difference between the inner diameter of the round hole of the outer restricting portion and the outer diameter of the armature shaft passing through the round hole;
2b having a bearing clearance on the inner peripheral side or outer peripheral side of the armature bearing;
When the maximum separation amount that the roller can separate from the outer peripheral surface of the clutch inner at the time of overrun of the one-way clutch is c,
c> a + b …………………… (1)
A starter characterized in that the relationship of the above formula (1) is established. The starter according to claim 1 or 2,
When the maximum eccentric amount of the clutch outer that occurs when two rollers adjacent in the circumferential direction bite into the narrow space of the cam chamber is d,
a + b> d …………………… (2)
A starter characterized in that the relationship of the above expression (2) is established. The starter according to any one of claims 1 to 3,
The clutch outer has a through hole formed in a radial center portion of the carrier, and the outer restricting portion having a ring shape is fitted to the inner periphery of the through hole.

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