JPS60111059A - Starter for internal-combustion engine - Google Patents

Abstract

PURPOSE:To make a starter compact in size, besides lightweight and absorb an impact as well as to aim at the promotion of low vibration and noiseless in design, by supporting an internal gear floatingly in a way of inserting a projection of a casing's inner end face into an engaging groove installed in one end of the internal gear, while making up the starter into such a structure as rendering the internal gear unrestricted by the casing inner circumference. CONSTITUTION:With a key switch turned on, a sun gear 9f gets turning so suddenly, and turning force to be imposed on the sun gear 8f is transmitted to an internal gear 15, while excessive impact torque produced by a motor is absorbed by means of elastic deformation in an internal gear fixed pin 10c and a rim part of the internal gear 15. After an amount of the elastic deformation in the internal gear 15 and the internal gear fixed pin 10c becomes maximum, a carrier 14a and an output shaft 14 both start their rotation, and this turning force is transmitted to a pinion 20a, making an internal combustion engine start. And, the internal gear can be floated as much as a portion for the amount of elastic deformation as a cantilever beam of a projection installed in a reduction gear casing, while the elastic deformation in the internal gear rim part also is not restricted in its outer circumference so that the amount of elastic deformation may be secured large enough, meaning that it is effective for uniform distribution in power.

Description

[Detailed Description of the Invention] [Field of Application of the Invention] The present invention relates to an internal combustion engine starter used for starting an internal combustion engine, and is an electric motor starter suitable for use in automobiles, etc., which is small and lightweight. This invention relates to a starter for an internal combustion engine that incorporates a planetary gear mechanism.

[Background of the invention]

BACKGROUND ART Conventionally, as a starter for an internal combustion engine, a type directly connected to an electric motor as shown in FIG. 1 has often been used. To explain the outline of this operation, when the driver turns on the key switch, the solenoid coil 1 is energized, which causes the shift lever 2 to start moving, and before the shift lever 2 completes its movement, the motor is energized and the armature 3 of the motor is energized. starts rotating.

At this time, shift 1-lever 2 is armature shirt 1-3a.
Since the one-sided clutch 4 and pinion 5a, which are engaged with the helical spline 3b integrally formed in the The pinion 5a engages with a ring gear (not shown) to start the internal combustion engine.

Starters for such internal combustion engines are also strongly required to be smaller and lighter due to the recent demands for energy saving and noise reduction in automobiles, but in the case of starters that are directly connected to the electric motor, there are problems such as magnetic saturation of the iron core. Due to this phenomenon, the required output of 1-lux could no longer be obtained, so there was a limit to miniaturization.In view of this drawback, a planetary gear mechanism was integrated into the product as in Japanese Utility Model Application Publication No. 58-132171. A method has been proposed, but as is well known, in a planetary gear mechanism, power is transmitted simultaneously through multiple planetary gears, so if the power is equally distributed between these planetary gears, the problem would be excessive. There are problems in that the reducer may be damaged due to the load or vibration and noise may increase. Incidentally, an important feature of a starter for an internal combustion engine is that both the driving side, that is, the electric motor, and the driven side, that is, the internal combustion engine, have a 1-lux characteristic that is WI striking. That is, the planetary gear reduction mechanism used in a starter for an internal combustion engine must not only distribute power evenly but also withstand impact loads. Considering this point of view, among the conventional power equalization mechanisms, firstly, the so-called sun gear floating type equalization mechanism, which restricts the sun gear only in the rotational direction with respect to the shaft, is the one on the internal combustion engine side. #This is not preferable because the impact load may be transmitted to at least the planetary gear pin and the meshing portion between the planetary gear and the internal gear. Similarly, the method of floating the carrier is undesirable in that the shear force generated by the motor can be transmitted to the meshing parts of the sun gear, planetary gears, and internal gears, and furthermore, the method of floating the carrier is undesirable because There is also a risk of tinging occurring. In other words, in order to satisfy both dynamic force distribution and shock load mitigation, the internal gear, which is a reaction force support member in a differential gear in a broad sense, should be supported floatingly so that it can move in the radial direction, and should also be able to be elastically deformed. I know that I should. In the above-mentioned Japanese Utility Model Publication No. 58-132171, ? #The structure allows the ring gear (internal gear) to absorb the impact load by moving in the axial direction, but the radial movement necessary for equal distribution of power is at most a υ cal spline. It is no exaggeration to say that it is virtually impossible to move in the radial direction if the backlash in the normal direction of the tooth surface is up to the minimum value, and considering the accuracy of the helical spline. In addition, in this method, the ring gear (internal gear) member has teeth on both the outer and inner peripheries to support the load, so stress concentration at the root of the teeth can be prevented and cracks can occur in the rim. The thickness of the rim must be increased, and the flexibility of the rim decreases, which also causes a decrease in power distribution.

[Purpose of the invention]

In view of the above points, an object of the present invention is to provide a starter for an internal combustion engine that is small and light, has no fear of breakage, and has low vibration and noise.

[Summary of the invention]

The present invention is characterized by an internal gear support system that can reduce the floating range of the internal gear and improve the flexibility of the internal pulley. A plurality of locking grooves are provided on the &lIi surface of the reducer casing, and a number of protrusions equal to or less than the cough grooves are provided on the inner end surface of the reducer casing facing the end surface, and these grooves and protrusions are engaged. In addition to transmitting the reaction force received by the internal gear to the reducer casing, a radial clearance is provided between the outer periphery of the internal gear and the inner periphery of the reducer casing, which is at least larger than the amount of elastic deformation occurring in the internal gear and the protrusion. be.

[Embodiments of the invention]

An embodiment of the present invention will be described below with reference to the drawings. Second
The figure is a longitudinal sectional view showing one embodiment of the present invention, and FIG. 3 is an enlarged view of the main part thereof. In the figure, 6 is armature 8
A motor housing rotatably supports one end of the motor housing 6 and fixes the stator 7. A fitting part 6a is provided at one end of the motor housing 6, and this fitting part 6a connects the reducer casing. Configure. Bragat 1
～9 and cover 10 are connected to main bracket 1 by port 1～
It is fixed and fitted to ~. The starter 7 constitutes a motor field composed of a plurality of magnetized permanent magnets, but since this is similar to a conventionally known DC motor, a detailed explanation will be omitted. Armature 8 is armature shaft 1-8
The core 8b is press-fitted into the approximate center of the core 8b.

It consists of a mitator 8h, one end of the armature shaft 8a is rotatably inserted into a bearing 6h that is integrally installed in the motor housing G, and the other end is equipped with a brake gear 1.
A bearing portion 8o rotatably supported by the bearing 8o and a sun gear 8F serving as an input to the planetary gear reducer are integrally formed. Motor housing 6, brackets 1 to 9 and cover 10
The starter is installed in the flywheel housing (not shown) of the internal combustion engine, along with several solenoid coils 11 for operating the starter. The cover 10 has a bearing part], which rotatably supports the starter output shaft 14 integrally formed with the carrier of the planetary gear reducer, in the center, and has a bearing part Oa on its end surface. Three extruded parts] Ob are formed concentrically with the bearing part 1.0 a at intervals of ~7 mm.

This extrusion part 10b has an inner car fixing pin I.
The pin 10c is press-fitted into the six pins, and the tip of the fixing pin 10c protrudes from the surface of the cover 10 facing the internal gear. An internal gear 15 is provided on the protrusion of the fixing pin 10c.
The groove 15a provided on the end face of the is engaged with the
The movement of the internal gear 15 is regulated within a certain limit in both the rotational direction and the radial direction.

The outer circumferential side of the internal gear 15 is offset by a bracket 1-9 whose inner circumference is larger than the outer circumference 15) of the internal gear 15, and between the internal gear 15 and the bracket 9, the internal gear 15 and A radial clearance h greater than the elastic deformation produced in the protrusion is formed.

The starter output shaft 14, which is rotatably supported by a bearing 10a of the cover 10 and a shaft 13a provided on the main bracket, has a carrier 14a integrally formed at one end, and a helical spline 14b formed approximately at the center. ing. The carrier 14a has a starter output shaft 14.
Three planetary gear support pins 14c are driven and fixed concentrically and at equal intervals, and each planetary gear support pin 10c has a bearing I6.
A planetary gear 17 inserted into the inner periphery is rotatably supported, and this 'M star gear 17 meshes with the sun gear 8f and the internal gear 15, respectively. The internal gear 15 and the carrier 14a constitute a so-called planetary planetary gear TIf reduction gear.

The helical spline 1/Ib formed approximately in the center of the starter output shaft 14 has an after J that is moved in the axial direction of the starter output shaft 14 by the lever 12 to the shift 1.
Helical spline 18 provided on the inner circumference of the stem of 8.
a is engaged, and the starter output shaft 14 and the outer 18 are coupled by the helical spline 18a to prevent relative rotation beyond a certain limit.A cam +8b is formed on the inner periphery of the other end of the outer 18. and this cam 1
A one-sided clutch is formed by a roller 19 inserted into the inner combustion engine 8b and an inner 20 at one end of which meshes with a ring gear (not shown) provided in the internal combustion engine.

Next, the operation of the stator of the present invention configured as described in -1 will be explained. The detailed operations of the relays and the like from when the driver turns on the key switch to when the pinion 20a engages with the ring gear are not particularly different from those of conventionally known starters for internal combustion engines, and will therefore be omitted. When the driver turns on the key switch, the solenoid coil 11 is energized and the shift 1 lever 12 starts to move.When the lever 12 has moved to the shift 1 to a certain position, the winding 8C of the armature 8 is energized. The armature 8° and therefore the sun gear 8f begin to rotate rapidly.

The rotational force applied to the sun gear 8f is first transmitted to the internal gear 15 via the tooth surface of the planetary gear 17.

Here, since the internal gear 15 is fixed to the reducer casing by the internal gear fixing pin 10c, the excessive impact torque generated by the motor is due to the elasticity of the internal gear fixing pin 10c and the rim of the internal gear 15. Then, after the amount of elastic deformation of the internal gear 15 and the internal gear fixing pin 10c reaches the maximum, the carrier 148 and the output shaft 14 start rotating via the planetary gear support pin 14c, and this rotation is transmitted through the helical splines L4b and 1.8a to the outer 18, further through the rollers 19 and the inner 20 to the pinion 20a, and starts the internal combustion engine.

At this time, an excessive i-lux may be applied to the output shaft 14 from the internal combustion engine due to poor starting or irregular ignition, or the one-way clutch may not disengage properly, causing the output shaft 14 to be accelerated. Since this is also a shocking phenomenon, since the internal gear 15 is elastically supported, these impact loads are absorbed by the internal gear supporting part, and at least the meshing part of the sun gear and the planet @JII is not affected by the impact. It is possible to prevent the load from acting. As described above, according to the present invention, it is possible to alleviate the impact load, which is a characteristic of starters for internal combustion engines.

In addition, the internal gear floating system can increase the distribution of power, etc. In other words, the internal gear force station 7. In addition, the elastic deformation of the internal gear rim is not constrained on the outer periphery and there is no problem of stress concentration caused by the helical spline, so the amount of elastic deformation of the internal gear can be large, which is greatly effective in equalizing power distribution. There is. Furthermore, since the assembly process of engaging the grooves and protrusions provided on the end face is much easier than the process of engaging gear couplings, it is possible to significantly reduce costs during mass production. Become.

Next, another embodiment of the present invention will be described with reference to FIG. FIG. 4 is a longitudinal cross-sectional view of the main parts of the starter for an internal combustion engine seen from the same viewpoint as FIG. 2, and is a view focusing in particular on the support portion of the internal gear. In this figure, the cover 10 has six extruded parts]O which are concentric with the bearing part 10a and extend toward the internal gear.
The one-way gear 15 is made of a synthetic resin material to reduce its mass and moment of inertia so that it can easily float, and a groove 15a that is slightly larger than the outer diameter of the extruded part Ob is formed. In this embodiment, the internal gear 15
The impact torque transmitted to the groove 15a is absorbed by the gap between the groove 5a and the extruded portion 10b and the elastic deformation mainly caused by the groove 15a. This second embodiment has the same effect as the first embodiment, and can further reduce the number of parts and further reduce the size and weight.In addition, the inertial resistance of the internal gear is small, making it easier to allocate power, etc. can be further improved.

〔Effect of the invention〕

As described above, according to the present invention, the internal gear is floatingly supported by providing a locking groove in the end surface of at least one end of the internal gear and inserting the protrusion provided on the inner end surface of the reducer casing into the groove. , and because the outer periphery of the internal gear is not constrained by the inner periphery of the ringing, the power distribution is high.
A starter for an internal combustion engine that absorbs impact loads can be obtained.

By this method, starters for internal combustion engines can be made smaller, lighter, and lower in cost, which greatly reduces energy consumption during production and use.

[Brief explanation of drawings]

FIG. 1 is a longitudinal sectional view showing a conventional starter for an internal combustion engine, FIG. 2 is a longitudinal sectional view showing an embodiment of the starter for an internal combustion engine of the present invention, and FIG. 3 is an enlarged view of the main part of FIG. FIG. 4 is a diagram showing another embodiment of the present invention. 6. Motor housing, 7... Starter, 8... Armature, 8f... Sun gear, 10b... Extrusion part,
10c...Internal gear fixed, I = Internal gear, 15a...
·groove. 17... Planetary gear. Figure 111 Z Plan 3 Figure "fJ4 Figure

Claims (1)

[Claims] 1. A planetary gear reduction mechanism is provided in an internal combustion engine to reduce the rotation of an electric motor used to start the internal combustion engine. In a starter for an internal combustion engine that transmits power to a ring gear, at least one end face of an internal gear serving as a reaction force member of a planetary gear mechanism is provided with a plurality of locking grooves, and the groove is provided with a plurality of locking grooves in the reducer casing. By inserting the protrusions provided on the opposing inner end surfaces, the reaction force received by the internal gear is transmitted to the reducer casing, and at least the internal gear A starter for an internal combustion engine, characterized in that a radial clearance is provided which is equal to or greater than the amount of elastic deformation occurring in the protrusion. 2. A feature characterized in that the plurality of grooves provided on the end surface of the internal gear of the planetary gear mechanism are made more attractive than the protrusions provided on the inner end surface of the reducer casing. Starter for the internal combustion engine described.