JPH01244163A - Coaxial type starter device - Google Patents

Abstract

PURPOSE:To make an electric motor into a high-powered one in spite of small size as well as to secure conformity between central axes to each armature turning shaft of both devices by supporting a carrier of the planetary gear device on a bearing of the armature turning shaft and a clutch outer of the overrunning device on a clutch inner via a bearing, respectively. CONSTITUTION:A front end of an armature turning shaft 11a of an electric motor 11 is supported on a carrier 15c of a planetary reduction gear 15 via a bearing 21. A clutch outer 16a of an overrunning clutch device 16 is supported on a clutch inner 16b via a bearing 24. Consequently, a bearing support part of an intermediate bracket, having supported the armature turning shaft 11a so far, can be disused. In consequence, a long magnetic pole is attachable to an inner circumferential surface of a yoke 11b, and thereby the motor 11 is made into a high-powered one in spite of small size. In addition, any eccentricity to the armature turning shaft 11a of the overrunning clutch device 16 and the planetary reduction gear 15 is avoided so that stable actuation is assurable.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to a coaxial starter device, and more particularly to a coaxial starter device used for starting a vehicle engine.

(Prior Art) A starter device conventionally used for starting a vehicle engine has a so-called two-shaft configuration in which an electromagnetic switch device for turning on power to a DC motor is placed on the side of the DC motor. there were. However, such a two-shaft starter device imposes significant restrictions on the engine layout when designing a vehicle, so the electromagnetic switch device is placed at one end in the axial direction of the DC motor, making the starter device look like a simple elongated cylindrical body. It was suggested that the shape be simple.

According to this proposal, as shown in FIG. 2, the coaxial starter device 1 includes a hollow armature rotating shaft 3 of a DC electric motor VA2, and a plunger rod of an electromagnetic switch device 4 arranged at the rear end of the DC motor 2. 4a through the internal passage 3a of the armature rotating shaft 3, and after being inserted into the internal passage 3a of the armature rotating shaft 3 in the output rotating shaft 5 coaxially disposed at the front end of the armature rotating shaft 3. It is configured to be able to push the output rotation shaft 5 forward by coming into contact with the end surface of the end portion.

In this coaxial starter device l, a sun gear 6a is formed on the outer periphery of the front end of the armature rotating shaft 3, and the sun gear 6a is
A plurality of planetary gears 6b are disposed in mesh with each other. These planetary gears 6b further mesh with an internal gear 6C formed on the inner peripheral surface of the machine frame 7, and are supported by the carrier 6e by a shaft 6d. These sun gear 6a and planetary gear 6b.

The planetary gear reduction device 6 is configured by an internal gear 6c, a shaft 6d, and a carrier 6C, and reduces the rotation of the armature rotating shaft 3. An overrunning clutch device 8 is fitted to the output rotating shaft 5, and its clutch inner 8a is provided on the output rotating shaft 5 and is connected to the internal passage 3a of the armature rotating shaft 3.
The output rotating shaft 5 slides in the axial direction while receiving rotational transmission from the clutch inner 8a. A pinion 9 is attached to the front end of the output rotation shaft 5 when the output rotation shaft 5 is engaged with or disengaged from an engine ring gear (not shown), and the pinion 9 rotates the engine ring gear when the output rotation shaft 5 slides forward.

Further, the front end of the yoke 2a of the DC motor 2 is bent inward to form an intermediate bracket 2b, and the inner edge of the intermediate bracket 2b is further axially inward (armature side).
The bearing holding portion 2c is formed by bending the bearing holding portion 2c. A needle bearing 2d is arranged in this bearing holding part 2c,
The armature rotating shaft 3 was supported on the front end side by this needle bearing 2d. In addition, in FIG. 2, the reference numeral 2e indicates a magnetic pole in the DC motor 2.

(Problem H to be solved by the invention) However, in the coaxial starter device proposed as described above, due to the presence of the bearing holding part 2c of the intermediate plaque 2b, the jig interferes with the installation of the magnetic pole, and the magnetic pole is not held in the bearing holding part. It can only be installed axially rearward than 2c, and as a result, the magnetic poles are short (to avoid this, the overall length must be lengthened to make the motor larger) to obtain the desired torque. .

Furthermore, when using a coaxial type as proposed above, it is difficult to accurately align the central axis of the planetary gear reduction device 6 and the central axis of the armature rotating shaft 3, and the former device is not connected to the latter rotating shaft. Since the planetary gear 6b is eccentric with respect to the central axis, it is in a very unstable state, and there is a risk that the planetary gear 6b may be damaged or generate abnormal noise when rotated at high speed or subjected to a large impact. In particular, in the case of a coaxial starter device, since the shaft 6d supporting the planetary gear 6b is fixed to a carrier 6e that is integrated with the clutch outer 8b of the overrunning clutch device 8, the clutch outer 8b also becomes eccentric, and as a result, the cam There was a risk that it would cause dents on the surface.

SUMMARY OF THE INVENTION The object of the present invention has been made to solve the problems of the conventional art, and is equipped with a small and high-output electric motor, and furthermore, the center axis of the planetary gear reduction device and the overrunning clutch device is aligned with respect to the armature rotating shaft. An object of the present invention is to provide a coaxial starter device that can achieve matching.

(Means for Solving the Problems) The present invention provides an electric motor in which an armature rotating shaft of an electric motor and an output rotating shaft, which is provided with a pinion at the front end and is supported slidably in the axial direction, are arranged on the same axis, and the electric motor A coaxial starter device that transmits rotation of a child rotation-shaft to the output rotating shaft via a planetary gear reduction device and an overrunning clutch device, the starter device comprising a carrier of the planetary gear reduction device and a clutch outer of the overrunning clutch device. are integrally formed, the carrier is supported by a bearing attached to the front end of the armature rotating shaft, and the clutch outer is connected to the clutch inner at a position adjacent to the front end surface of the roller in the overrunning clutch device. It is characterized by being supported by fitted bearings.

(Function) In the coaxial starter device of the present invention, the front end of the armature rotating shaft of the electric motor is supported by a bearing interposed between the carrier of the planetary gear reduction device, and the clutch outer integral with the rear of the gear Supported by a bearing in the clutch inner. As a result, the armature rotating shaft is rotatably supported without the need for a needle bearing, etc., which was conventionally supported by an intermediate bracket, and its rotation is transmitted to the clutch outer of the overrunning clutch device via the planetary gear reduction device. is transmitted from the outer to the inner via the rollers to drive the output rotating shaft.

(Embodiments) Hereinafter, the coaxial starter device of the present invention will be described in more detail with reference to embodiments shown in the accompanying drawings.

FIG. 1 shows a coaxial starter device 10 according to an embodiment of the present invention. The coaxial starter device 10 of this embodiment includes a DC motor 11 having a yoke Ilb which also serves as a machine frame of the device, and a tubular armature rotating shaft 11a disposed on the central axis of the yoke Ilb. Tubular armature rotating shaft 11
An armature core llc is press-fitted and fixed to the outer periphery of a.

On the front end side in the axial direction of the DC motor 11 (on the right side as seen in FIG. 1), there is an output rotating shaft 12 on the same axis as the armature rotating shaft 11a.
is located. The output rotating shaft 12 is slidably supported in the axial direction via a sleeve bearing 14 which is inserted into the inner passage 13 of the armature rotating shaft 11a at its rear end and is interposed between the inner circumferential surface of the armature rotating shaft 11a.

The rotational force of the armature rotating shaft 11 a is transmitted to the output rotating shaft 12 via a planetary gear reduction device 15 and an overrunning clutch device 16 . That is, the planetary gear reduction device 15 includes a sun gear 15a integrally formed on the outer periphery of one end of the armature rotating shaft fla, and an internal gear formed on the front plaquette 17 which is the machine frame of the starter device 10. 15b, and a plurality of idling gears 15e rotatably supported by a shaft 15d fixed to a carrier 15c that meshes with the sun gear 15a and the internal gear 15b and is integral with the clutch outer 16a of the overrunning clutch device W16. has been done. Further, the helical spline 16c formed on the inner circumferential surface of the clutch inner 16b of the overrunning clutch device 16 meshes with the helical spline 12a formed on the outer circumferential surface of the output rotating shaft 12, so that the output rotating shaft 12 It is possible to slide in the axial direction while receiving rotational force from the inner 16b. This output rotation shaft 12
A pinion 18 that meshes with the ring gear of the engine is attached to the end protruding from the front bracket 17 of the engine.

On the other hand, an electromagnetic switch device 19 is provided at the rear end side of the DC motor 11 (on the left side in FIG. 1). The function of this electromagnetic switch device 19 is the same as that of the coaxial starter device shown in FIG. The output rotating shaft 12 is pushed out by the movement of the rod 4a, the binion 18 is brought into mesh with the engine ring gear, and the DC motor 11 is powered on.

In the case of the coaxial type, the configuration in which the binion and the engine ring gear are brought into mesh by movement of the rod of the electromagnetic switch device is as follows.

That is, the rod 4a operatively connected during the plunge (not shown) of the electromagnetic switch device 19 disposed on the same axis as the armature rotation shaft 11a of the DC motor 11 is connected to the internal passage 13 of the armature rotation shaft 11a. The steel ball 20 contacts the back wall of the hole 12b formed in the end face of the output rotating shaft load 2 through the steel ball 20.

Furthermore, the carrier 15c in the planetary gear reduction device 15 has a pole bearing 21 fitted on its inner circumference, and the pole bearing 21 is connected to the sun gear 15 formed on the armature rotating shaft 11a.
It is supported by being attached to a small diameter stepped portion 22 formed on the outer periphery of the armature rotating shaft 11a at the front end adjacent to the armature rotating shaft 11a.

Thereby, the movement of the carrier 15c in the radial direction is completely restricted by the pole bearing 21, so there is no room for eccentricity. Further, the front end of the clutch inner 16b of the overrunning clutch device 16 protrudes toward the pinion side, and a bearing 23 is fitted on a partial outer periphery of the clutch inner 16b, and the bearing 23 is held by the front bracket I7.

As a result, the revolution center axis of the planetary gear 15e and the rotation center axis of the overrunning clutch device 16 are aligned with the armature rotation axis 1.
It coincides with the center axis of 1a, and there is no room for eccentricity as a whole.

Furthermore, in the coaxial starter device 10 of this embodiment, the clutch outer 16a of the overrunning clutch device 16 is adjacent to the roller 16d at its front end, and the clutch inner 1
6b is supported by a ball bearing 24 fitted to the shaft 6b. As a result, since the clutch inner 16b is supported by the front bracket 17 by the bearing 23, the front end of the armature rotating shaft 11a is stably held by the support by the carrier 15c by the bearing 22.

Note that rubber or resin is attached to the outer circumferential surface of the outer race of the ball bearing 24 disposed between the clutch inner 16b and the clutch outer 16a, for example by baking.
This effectively prevents grease from flowing inside the clutch. Furthermore, arranging the ball bearing 24 at the front end side of the overrunning clutch device 16 adjacent to the roller 16 between the clutch inner 16b and the clutch outer 16a means that the cover conventionally provided in this area is This has the advantage of eliminating the need for caulking work and groove machining on the outer periphery.

(Effects of the Invention) As explained above, according to the coaxial starter device of the present invention, the front end of the armature rotating shaft of the electric motor is supported by the carrier of the planetary gear reduction device via the bearing, and is integrated with the carrier. Since the clutch outer of the overrunning clutch device is supported by the clutch inner via a bearing,
The bearing holding part of the intermediate bracket that conventionally supported the armature rotating shaft can be eliminated, and as a result, long magnetic poles can be attached to the inner peripheral surface of the yoke, making it possible to make the motor compact and high output. Stable operation can be ensured by avoiding eccentricity of the overrunning clutch device and the planetary gear reduction device with respect to the armature rotating shaft.

[Brief explanation of the drawing]

FIG. 1 is a partially cutaway front view of a coaxial starter device according to an embodiment of the present invention, and FIG. 2 is a coaxial starter device proposed to improve the drawbacks of conventional starter devices. FIG. DESCRIPTION OF SYMBOLS 10... Coaxial starter device, 11... DC motor, 11a... Armature rotating shaft, 12... Output rotating shaft,
15... Planetary gear reduction device, 15c... Carrier,
16... Overrunning clutch device, 16a...
・Clutch outer, 16b...Clutch inner, 18
... Pinion, 19... Electromagnetic switch device, 21.
...Bearing, 24...Ball bearing. Note that the same reference numerals in each figure indicate the same or corresponding parts.

Claims (1)

[Claims] The armature rotating shaft of the electric motor and an output rotating shaft equipped with a pinion at the front end and slidably supported in the axial direction are arranged on the same axis, and the rotation of the armature rotating shaft is controlled by a planetary gear reduction gear and overrunning. A coaxial starter device that transmits transmission to the output rotating shaft via a clutch device, wherein the carrier of the planetary gear reduction device and the clutch outer of the overrunning clutch device are integrally formed, and the carrier The clutch outer is supported by a bearing attached to a front end of a shaft, and the clutch outer is further supported by a bearing fitted to a clutch inner at a position adjacent to a front end surface of a roller in the overrunning clutch device. Coaxial type starter device.