JPH0571452A - Starter - Google Patents

Abstract

PURPOSE:To improve assembling performance of a reduction-type starter and reduce a reversal load caused to an internal gear. CONSTITUTION:A magnet holder part 10B is integrated with an internal gear part 10C. The magnet holder part 10B is inserted into the yoke 1D, so that a field magnet is positioned. The internal gear and the magnet holder are united to be a part, and work processes are reduced. Detents on an outer peripheral surface of the internal gear are dispensed with, and a reversal load to be applied to the internal gear is reduced. In addition, the internal gear is fixed in an axial direction. A shape of the outer peripheral surface of the internal gear is simplified.

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 a reduction type internal combustion engine using a planetary gear, and more particularly to a starter suitable for an automobile engine.

[0002]

2. Description of the Related Art Since a reduction type starter can obtain a large starting torque, it can be easily started even with a large horsepower engine, and therefore it has been widely used as the performance of automobiles has increased. Among them, the reduction type starter using a planetary gear as a reduction mechanism, which is described in, for example, Japanese Utility Model Laid-Open No. 63-132877, is easily reduced in size. -It is becoming more and more common.

In addition to the above-mentioned publications, the related apparatus of this type is, for example, JP-A-56-66.
450, JP-A-58-206873, JP-A-60-
No. 53663 or JP-A No. 2-218865 can be mentioned.

[0004]

SUMMARY OF THE INVENTION The above-mentioned prior art is concerned with the improvement of the assemblability at the time of assembling the starter and the reciprocal load generated between the rotation preventing portion and the internal gear tooth portion of the internal gear of the planetary gear reduction mechanism. It is not considered, requires extra steps for assembly, takes a lot of time, and
There is a problem that a load that is applied to the anti-rotation protrusion on the outer peripheral surface of the null gear and a load that is applied to the tooth portion on the inner peripheral surface of the internal gear are contradictory and cause damage.

An object of the present invention is to improve the assemblability of the starter, and further to alleviate the reciprocal load generated in the internal gear.

[0006]

In order to achieve the above object, a magnet holder and an internal gear are integrated and processed as one component, and the magnet holder has a rotation preventing function for the internal gear. It is something that can be held.

[0007]

By integrally molding the magnet holder and the internal gear, the number of parts can be reduced and the number of assembling steps can be reduced. In addition, the magnet holder
Since the rotation of the internal gear can be prevented, it is not necessary to provide a rotation stopper on the outer peripheral surface of the internal gear, and the reciprocal load generated in the internal gear can be reduced.

[0008]

The starter according to the present invention will be described in detail below with reference to the illustrated embodiments. First, FIG. 2 shows an overall configuration of an embodiment of a starter according to the present invention.
In the figure, 1 is a motor, 2 is a planetary gear reduction mechanism, 3 is an overrunning clutch, 4 is a pinion, 5 is a center bracket, 6 is a magnetic switch, 7 is a shift lever, and 8 is a ring gear. Motor 1
Is an armature 1A, an armature shaft 1B, a field magnet 1C,
A permanent magnet field type DC motor having a yoke 1D is provided with an armature gear 1E at one end of an armature shaft 1B.

The planetary gear reduction mechanism 2 includes an armature gear 1.
Equipped with three planetary gears 2A having E as a sun gear, an internal gear 2B meshing with the planetary gears 2A, a shaft 2C of the planetary gear 2A, and a pinion shaft flange portion 2D holding the shaft 2C, and an armature gear 1E and an interface gear 2E. -Three planetary gears 2A arranged at equal intervals in an annular space formed between the null gears 2B are in mesh with each other.

The three planetary gears 2A revolve around the armature shaft 1B while rotating about the shaft 2C attached to the pinion shaft flange 2D, and rotate the armature shaft 1B at a predetermined reduction ratio. Shaft 4A of pinion 4 through overrunning clutch 3
Acts to communicate to.

The center bracket 5 pivotally supports the shaft 4 and functions to assemble the motor 1 together with the yoke 1D. Next, the operation of the starter shown in FIG. 2 will be described.

When a key switch (not shown) is turned on, a current is supplied to the magnetic switch 6, and the overrunning clutch 3 and the pinion 4 are moved to the right in the figure via the shift lever 7, whereby The pinion 4 meshes with a ring gear 8 engaged with a crankshaft of an internal combustion engine (not shown).

At the same time, the contacts built in the magnetic switch 6 are turned on, current is supplied to the motor 1, torque is generated in the armature 1A, and the armature shaft 1
B rotates, and this rotation causes a predetermined deceleration on the pinion shaft 4A via a planetary gear reduction mechanism 2 including an armature gear 1E at the tip of the armature shaft 1B, a planetary gear 2A, and an internal gear 2B. It is transmitted in a ratio, and further transmitted to the pinion 4 via the helical spline 3A and the overrunning clutch 3 to rotate the ring gear 8 and start the internal combustion engine.

Returning to FIG. 2, reference numeral 10 denotes an integrally molded member which is characteristic of this embodiment. As shown in FIG. 1, a magnet holder portion 10B and an internal gear portion 10C are provided on both sides of a ring-shaped main body portion 10A. It is integrally molded with a synthetic resin material called engineering plastic (high-performance synthetic resin). Then, when assembling the starter, from the magnet holder portion 10B to the main body portion 10A,
2 is inserted into the yoke 1D of the motor 1 in the direction of arrow A in FIG. 1, and the internal gear portion 10C has a cylindrical portion of the center bracket 5 as shown in FIG. Are fitted.

Therefore, for this reason, the ring-shaped main body 10
The outer diameter dimension of A and the magnet holder portion 10B and the inner diameter dimension of the yoke 1D of the motor 1 are made to have the same dimension with a clearance enough to allow fitting with a predetermined force. The outer diameter of the internal gear portion 10C and the inner diameter of the cylindrical portion of the center bracket 5 are also made to have the same dimension with a predetermined clearance.

As is apparent from FIG. 1, the magnet holder portion 10B comprises a plurality of projections 10b having a plurality of arc-shaped cross sections which project from the ring-shaped main body portion 10A in a direction parallel to the axis of the motor. As shown, the field magnets 1C (and auxiliary magnetic poles (not shown)) are press-fitted to fix them. That is, a plurality of field magnets 1C
Are arranged and fixed at equal intervals on the inner peripheral surface 1f of the yoke 1D. At this time, the side faces 10b 'of the projections 10b are press-fitted between the field magnets 1C, whereby the yoke of the field magnet 1C is pressed. Positioning for 1D will be automatically provided.

Further, the protrusion 10 of the magnet holder portion 10B.
On the other hand, a concave groove 10e is formed in b, and correspondingly, a plurality of convex portions 1g are formed on the inner peripheral surface 1f of the yoke 1D. Therefore, when the integrally molded member 10 is inserted into the yoke 1D as shown by the arrow A in FIG.
Each of them engages with the convex portion 1g and acts as a detent for the integrally molded member 10 with respect to the yoke 1D. Therefore, according to this embodiment, the torque reaction force appearing in the internal gear portion 10C is surely secured. 1D, the integrally molded member 10 rotates with respect to the yoke 1D,
It is possible to prevent the displacement.

According to this embodiment, the following effects can be obtained.

The magnet holder portion 10B and the internal gear portion 10C are integrally molded of synthetic resin to form an integrally molded member 1
Since it is set to 0, the number of parts can be reduced, and the work man-hours at the time of assembling can be reduced.

The concave groove 1 is formed in the protrusion 10b of the magnet holder 10B.
0e is provided and fitted with the convex portion 1g of the yoke 1D to prevent rotation. Therefore, there is no need to provide a rotation stopper on the outer peripheral surface 10f of the internal gear portion 10C. As shown in FIG. 3, a reciprocal load is generated by the tooth portion load F1 of the internal gear 2B and the anti-rotation load F2, which can be eliminated as shown in FIG. Can be relaxed. Further, by fitting the concave groove 10e and the convex portion 1g, the internal gear 2B can be reliably fixed in the axial direction.

Further, since it is not necessary to provide a detent on the outer peripheral surface 10f of the internal gear portion 10C, the internal gear portion 10C is not required to be rotated.
The outer diameter of the null gear portion 10C and the inner diameter of the center bracket 5 can be made the same, and as a result, the shape can be simplified and foreign matter can be prevented from entering the internal gear 2B. Internal gear 2 during molding
The gear accuracy of B can be improved.

By the way, the field magnet of the motor is usually fixed to the yoke by a method such as welding or bonding. Therefore, as in the above embodiment, the groove 10 for preventing rotation is special.
The present invention can be implemented without providing e and the convex portion 1g.

[0023]

Since the present invention is constructed as described above, the following effects are achieved.

By integrally molding the magnet holder and the internal gear with synthetic resin to form one component, the number of components can be reduced and the number of man-hours required for assembly can be reduced.

A detent can be eliminated from the outer peripheral surface of the internal gear, and the outer diameter and center of the internal gear can be eliminated.
The inner diameter of the bra can be made the same and the shape can be simplified, and foreign matter can be prevented from entering the inside of the internal gear. Further, the gear accuracy of the internal gear during resin molding can be improved.

[Brief description of drawings]

FIG. 1 is a perspective view of an integrally molded member and a yoke in an embodiment of a starter according to the present invention.

FIG. 2 is a partial sectional view of a starter according to an embodiment of the present invention.

FIG. 3 is an explanatory diagram of stress of an internal gear in a conventional technique.

FIG. 4 is an explanatory diagram of stress of an internal gear according to an embodiment of the present invention.

[Explanation of symbols]

 F1 Non-rotating load F2 Tooth load 1 Motor 1A Armature 1B Armature shaft 1C Field magnet 1D Yoke 1E Armature gear 1f Inner peripheral surface of yoke 1D 1g Convex part 2 Planetary gear reduction mechanism 2A Planetary gear 2B Planetary gear 2A Planetary gear 2A Axis 2D Pinion shaft Collar 3 Overrunning clutch 4 Pinion 5 Center bracket 6 Magnetic switch 7 Shift lever 8 Ring gear 10 Integrated molding member 10A Main body 10B Magnet holder 10C Internal gear 10b Protrusion 10b 'Protrusion side 10e Groove

Claims (4)

[Claims] 1. A starter having a magnet motor and a planetary gear reduction mechanism, wherein a magnet holder portion for positioning a field magnet of the magnet motor and an internal gear portion of the planetary gear reduction mechanism are integrally configured. A starter characterized by having 2. The invention according to claim 1, wherein a concave groove and a convex portion that engage with each other are formed on the outer periphery of the magnet holder portion and the inner surface of the yoke of the magnet motor. Starter. 3. The starter according to claim 1, wherein the outer peripheral surface of the internal gear portion is fitted to the inner peripheral surface of the center bracket of the magnet motor. 4. The starter according to claim 1, wherein the magnet holder portion and the internal gear portion are formed as an integrally molded product of a synthetic resin material.