JPS63195381A - Starter for engine - Google Patents

Abstract

PURPOSE:To shorten the total length of a coaxial type starter by forming an armature rotating shaft and an inside cam surface at the same time in a forging process or the like, and then fitting the fixing tube of an armature core on the small diameter part of the shaft with pressure in order to fix the armature core without deformation of the cam surface. CONSTITUTION:On the armature rotating shaft 16 of the armature 13 of a d.c. motor 15, cam surfaces 16a which constitute an over running clutch mechanism are formed on the inside surface in one body. And a small diameter part 16b is formed on one edge of the outside surface in a range of its longitudinal axial length on which no cam surface is formed. A tube 55 on which turning stop is rolled, is press-fitted on this part 16b. An armature core 17 is fixed on the outside of this tube 55. Thus, a means for attaching the armature core on the armature rotating shaft without deforming the cam surface is achieved, and the total length of the coaxial type starter is further shortened, and it becomes possible to make the starter light and small.

Description

DETAILED DESCRIPTION OF THE INVENTION (Industrial Utilization Public Funds) The present invention relates to an engine starter, and more particularly to a coaxial engine starter used for fine starting of a vehicle.

(Prior Art) Conventionally, a starter used for fine starting of a vehicle has been constructed as shown in FIG.

A conventional starter 1 shown in FIG. 4 includes a DC motor 2 and an overrunning clutch device 4 that is slidably fitted on an extended shaft portion of an armature rotating shaft 3. One end is engaged with the plunger rod of an electromagnetic switch device 5 disposed on the side of the DC motor 2 in order to slide the armature on the extended shaft portion of the armature rotating shaft 3, and the other end is attached to the overrunning clutch device 4. A shift lever 7 was engaged with an annular member 6.

(Problems to be Solved by the Invention) As described above, the conventional starter 1 requires the shift lever 7 for sliding the overrunning clutch device 4 on the extended shaft portion of the armature rotating shaft 3, and furthermore, Since the electromagnetic switch device 5 that operates the shift lever 7 and turns on the power to the DC motor 2 is arranged on the side of the DC motor 2 in a so-called two-shaft configuration, there are major restrictions on the engine layout when designing the vehicle. It was Yofuyu.

In order to avoid such problems, it has been proposed to arrange the electromagnetic switch device at one end in the axial direction of the DC motor so that the starter has a simple shape such as a simple elongated cylindrical body. According to this proposal, the basic idea is to make the armature rotating shaft of a DC motor hollow, and to extend the plunger rod of the electromagnetic switch device that conventionally operates the shift lever through the internal passage of this armature rotating shaft to the output rotating shaft. This type of starter is called a coaxial starter because the armature rotating shaft of the DC motor and the rod of the electromagnetic switch device are arranged on the same axis. In order to further shorten the axial length of the coaxial starter with this basic configuration and make it more compact, we developed an engine with an overrunning clutch mechanism built into the armature rotating shaft that constitutes the armature of the DC motor. A starter was suggested.

An engine starter with a built-in overrunning clutch mechanism has an enlarged-diameter recess formed on the inner periphery of the armature rotating shaft, a plurality of cam surfaces formed on the inner periphery of the recess, and inserted into the armature rotating shaft. A model space is formed between the clutch inner and the clutch inner, and a roller and a pressure spring are respectively arranged in this space. That is, the starter is configured such that the armature rotating shaft also serves as a clutch outer of the overrunning clutch device.

However, in such engine starters, many thin grooves like grooves are formed in the circumferential direction on the outer peripheral surface of the armature rotating shaft for attaching the armature core, but such grooves are generally Formed by rolling. However, in the rolling process, the armature rotating shaft must be strongly pressed against the rolling tool, which causes the problem of deformation of the cam surface for the overrunning clutch mechanism created on the inner peripheral surface of the armature rotating shaft. Ta.

SUMMARY OF THE INVENTION An object of the present invention was to solve the problems of the conventional art, and to provide a DC motor with an overrunning clutch mechanism built into the inner circumference of the armature rotation shaft. To provide an engine starter in which an armature core can be attached to the outer periphery of the starter without deforming the surface.

(Means for Solving the Problems) In the engine starter of the present invention, the armature of the DC motor has a plurality of cam surfaces constituting an overrunning clutch mechanism on its inner peripheral surface, and The armature rotating shaft is provided with an armature rotating shaft having a small-diameter stepped portion formed at one end on the outer circumferential surface in the axial length range that is not covered by the axial length, and having a flange-like stopper portion projecting radially outward on the outer circumferential edge of the other end. A cylindrical body with a rotation preventing rolling part formed on the outer circumferential surface is press-fitted into the small diameter stepped part of the cylinder body, and the armature core to be attached to the armature rotating shaft is fitted by the rotation preventing rolling part formed on the outer circumferential surface of the cylindrical body. It is characterized by being fixed.

(Function) According to the engine starter of the present invention, the armature rotating shaft of the armature of the DC motor is formed together with the cam surface on the inner circumference by forging or the like, and the armature core is attached to the small diameter stepped portion of the armature rotating shaft. A cylindrical body for fixing is press-fitted. Therefore, the armature rotating shaft is formed without deforming the cam surface formed on the inner peripheral surface, and the armature core is firmly fixed to the rotating shaft.

(Embodiments) Hereinafter, preferred embodiments of the engine starter of the present invention shown in the accompanying drawings will be described in more detail.

FIG. 1 shows an engine starter 10 according to an embodiment of the present invention.

The engine starter 10 of this embodiment includes permanent magnets 12 that are fixed to the inner peripheral surface of a yoke 11 that constitutes a magnetic circuit and forms an outer wall at intervals in the local direction, and that are rotatable at the center of the yoke 11. The motor includes a DC motor 15 mainly composed of an armature 13 disposed at the center and a face-shaped commutator 14 provided at one end of the armature 13.

The armature 13 of this DC motor 15 is composed of a hollow armature rotating shaft 16 and an armature core 17 attached to the outer periphery of the rotating shaft. This armature rotating shaft 16
A diameter-expanding recess is formed on the inner peripheral surface of the hollow portion, and a plurality of cam surfaces 16a are formed in the circumferential direction on the curved surface of the recess. A face-shaped commutator 14 fitted on the outer periphery of one end of the armature rotating shaft 16, that is, on the left side as seen in FIG. It is arranged in a plane perpendicular to the axis 16, and each segment is connected to the end of an armature coil 19 wound around an armature core 17.

The plurality of brushes 18 are supported by a plastic brush holder 20 that is formed integrally with the yoke 11 and arranged outside the rear bracket part 11a that constitutes a grounding circuit, and is inserted into each opening formed in the rear bracket part 11a. from the spring 2 against the sliding surface of the commutator 14.
1. Toraya bracket part 11
A bearing 22 is fitted into the inner circumferential surface of the central opening of a, and the bearing 22 supports the rear end of the armature rotating shaft 16, that is, the end on the commutator side. The brush holder 20 described above has a fixed contact 23 connected to a terminal (not shown) inserted into the rear part, and a terminal 24 to which a positive lead wire (not shown) of the brush 18 is welded to the fixed contact is attached with a screw 25. It is constructed in a fixed manner.

Incidentally, the cam surface 16a formed on the curved surface of the enlarged diameter concave portion of the armature rotating shaft 16 constitutes an overrunning clutch mechanism. That is, a tubular inner 26 is inserted into the hollow portion of the armature rotation shaft 16 over the axial length range where the cam surface 16a is formed, and the inner tube 26 is inserted between the armature rotation shaft 16 and the yoke 1.
They are rotatably supported by bearings 28 and 29, respectively, with respect to a front bracket 27 that is attached to the front gs (on the right side in FIG. 1) of the housing 1 and fixed to the jack bracket portion 11a with a through bolt. Each cam surface 16 formed on the outer peripheral surface of the inner 26 and the curved surface of the enlarged diameter concave portion of the armature rotating shaft 16
A plurality of wedge-shaped spaces are defined by a and each wedge-shaped space includes a roller 30 for engaging and connecting the cam surface 16a and the outer peripheral surface of the inner 26, and a spring that presses the roller 30 in the engagement direction. (not shown) are arranged.

In this way, the overrunning clutch mechanism is composed of the inner 26, the roller 30, the pressing spring, etc. together with the cam surface 16a, and the armature rotating shaft itself also serves as the clutch outer and carries out one function of the mechanism. There is.

A pinion shaft 31, which is an output rotation shaft, is disposed in the inner passage of the tubular inner 26, and the inner 26 and the pinion shaft 3
1 and 2 are engaged with each other by vertical splines formed on the inner and outer peripheries thereof so that rotation can be transmitted and axial movement is possible. The front end of the pinion shaft 31 is connected to the engine's ring gear (
A pinion 31m that engages with the motor (not shown) is integrally formed.

This pinion shaft 31 is supported by a bearing 32 that is fitted and fixed on the inner surface near the rear of the inner 26, and between the above-mentioned bearing 32 and a retaining ring 33 attached to the outer periphery of the rear end of the pinion shaft 31, there is a A spring 34 is arranged to return the spring 31 to its original position.

A recess 35 is formed in the end surface at the rear end of the pinion shaft 31, and a cylindrical first holder 3 with one end open is provided in the recess 35.
6 is loosely fitted, and a steel ball 37 that receives thrust force is disposed between the other end closed portion of the first holder 36 and the true wall of the recess 35.

Furthermore, the engine starter 10 of this embodiment slides the output rotating shaft 31 and is connected to a vehicle key switch (not shown).
It includes an electric/magnetic switch device 40 (hereinafter simply referred to as a switch device) having a switching function of turning on a contact so that power can be supplied from the battery to the DC motor 15 by closing.

This switch device 40 is connected to the outer side of the rear bracket part 11a by bolts 41, and the switch group [40 is made of plastic supported by front and rear cores 43m and 43b which together with the case 42 constitute a magnetic path. It is composed of an excitation coil 44 wound around a bobbin, a plunger 45 slidably disposed in the central opening of the bobbin, and a moving assembly 46 attached to the plunger 45. The plunger 45 is acted upon by a coil spring 47 disposed between it and the front core 43a so as to return to the original position shown in FIG. 1 when the key switch is off.

The moving assembly 46 has one end fixed to the plunger 45 and the other end fixed to the first holder 3 at the rear end of the pinion shaft 31 described above.
6 and a rod 48 disposed opposite to the rod 4 .
A third holder 49 having an opening 49a that opens toward the pinion shaft is fixed to the outer periphery of the pinion 8 on the plunger side. This third holder 49 has two insulators 50a.
, 50b, a movable contact body 50 having a movable contact 50c sandwiched between the movable contacts 50c and 50b is slidably mounted on the outer circumferential portion of the movable contact body 50. A second holder 51 is fitted to the other end of the rod 48 so as to be slidable in the axial direction on the outer curved surface of the rod, and the second holder 51 and the inner end surface of the opening of the third holder 49 are connected to each other. A spring 52 is disposed in between to press the pinion shaft 31 to the right, that is, to the front as viewed in FIG. Further, a spring 53 is arranged between the other end surface of the rod 48 and the inner end surface of the first holder 3G for pressing the pick-up shaft 33 forward. Note that reference numeral 54 denotes a non-magnetic plate that closes the rear end of the case 42, serves as a stopper when the plunger 45 returns to the rear, and also forms the rear wall of the electromagnetic switch device 40.

In the engine starter 10 as described above, the armature rotating shaft 16 constituting the armature 13 of the DC motor 15 has a small diameter stepped portion 16b at one end on the outer peripheral surface in the axial length range where the cam surface 16a is not formed. is forming. Also,
A flange-shaped stopper portion 16c that projects radially outward is integrally formed on the outer peripheral edge of the other end of the armature rotating shaft 16.

As shown in FIG. 2, a cylindrical body 55 having a rotation preventing rolled portion 55a formed on its outer peripheral surface is press-fitted into and fixed to the small diameter stepped portion 16b of the armature rotating shaft 16.

The anti-rotation rolling portion 55a is formed by strongly pressing a rolling tool against the outer circumferential surface, such as in so-called knurl rolling, to form a large number of thin grooves and knurlings in the local direction. The outer diameter of this cylindrical body 55 is the same as the outer diameter of the cam surface forming portion of the armature rotating shaft 16, so when the cylindrical body 55 is press-fitted into the small diameter stepped portion 16b of the armature rotating shaft 16,
The outer circumferential diameter of the assembled shaft is as follows, excluding the stopper part 16c at the other end.
be equal over its entire length.

In this way, the armature rotating shaft 1 is formed by press-fitting the cylindrical body 55.
6 is equipped with an armature 117 which is made up of a large number of discs 17a stacked one on top of the other in the axial direction. Each disc 17a of the armature core 17 has a large number of notches 17b formed in the center thereof, and a plurality of notches 17b, through which the armature coil 19 is passed, on the outer periphery, as shown in FIG. 3 (al) and FIG. 3 (bl). An opening 17c is formed into which the armature rotating shaft 16 is inserted.Furthermore, each of these discs 17a has a concave portion on one surface and a convex portion on the other surface corresponding to the concave portion at the same position. A half-punched locking portion 17d is provided.

When these discs 17& are stacked together in the axial direction, the convex part of each locking part 17d fits into the concave part of the adjacent disc, and all of them are engaged with each other in the circumferential direction. be stopped. When the armature core 17, which is the aggregate, is attached to the armature rotating shaft 16, it is prevented from falling off by the stopper portion 16c at the other end, and is prevented from rotating by the outer circumferential surface of the cylindrical body at one end. The core 17 is press-fitted at the rolled portion 55a.
The entire armature is fixed without movement relative to the armature rotation axis in the circumferential direction.

The armature rotating shaft 16 is formed by surface treatment such as carburizing and quenching to provide strength suitable for its intended use.

Next, the operation of the engine starter 10 of the above-described embodiment will be explained. First, when the key switch (not shown) is turned off, the excitation coil 44 is not energized and therefore is not excited, and only the force of the spring 47 is acting on the plunger 45, so the movable assembly 46 is located at the rear. , the plunger 45 is in contact with the plate 54. In this state, the fixed contact 23 and the movable contact 50a are in an open state, so the DC motor 15 is stopped, and the pinion shaft 31 is also positioned rearward by the spring 34.

When the key switch is turned on, the excitation coil 44 is energized, the plunger 45 is energized, the movable assembly 46 moves forward, and the movable liquid fi 50 c comes into contact with the fixed contact 23. Therefore, the armature coil 19 is energized via the brush 18 and commutator 14, and the DC motor 15 is started. On the other hand, the pinion shaft 31 is pushed forward by the springs 52, 53 of the moving assembly 46, and at the same time as the DC motor is started, the pinion shaft 31 is pushed forward to the outer periphery of the engine flywheel. The provided ring gear and the binion 31a mesh with each other. After the engine is started, when the pinion shaft 31 and the inner 26 are reversely biased by the ring gear and rotate at a higher speed than the armature rotation shaft 16, the engagement between the inner 26 and the armature rotation shaft 16 is released by the one-way overrunning clutch action. , the armature rotating shaft 16 idles. When the key switch is turned off upon completion of starting, the power supply is cut off, the moving assembly 46 returns to the rear along with the plunger 45 by the action of the spring 47 in the electromagnetic switch device 40, and the pinion shaft 31 moves rearward by the action of the spring 34. Return.

(Effects of the Invention) As explained above, according to the engine starter of the present invention, the armature core can be attached to the armature rotating shaft which has the force port surface for the overrunning clutch mechanism formed on the inner peripheral surface. Since the means can be formed without deforming the cam surface, the total length of the coaxial starter can be further shortened to make it lighter and smaller.

[Brief explanation of the drawing]

FIG. 1 is a sectional view showing an engine starter according to an embodiment of the present invention, FIG. 2 is a perspective view showing a cylindrical body press-fitted into the armature rotating shaft in the engine starter of FIG. 1, and FIG.
Figure (,) is a perspective view of a disk constituting the armature core, and Figure 3 (bl is a cross section of the disk taken along line I(b)-1(b) in Figure 3 (1k)). 4 is a cross-sectional view of a conventional engine starter. 10... Engine starter, 13... 1161 child, 15... DC motor, 16... Armature rotating shaft, 1
6 &... cam surface, 16b... small diameter stepped portion, 16C...
- Stopper part, 17... Armature core, 26... Inner, 3G... Roller, 31... Pinion shaft (output rotating shaft), 40... Electromagnetic switch device, 55...
Cylindrical body, 55a... rotation preventing rolled part. Note that the same reference numerals in the figures indicate the same or equivalent parts. 17a Procedural amendment (voluntary)

Claims (3)

[Claims] (1) A plurality of cam surfaces constituting an overrunning clutch mechanism are created on the inner peripheral surface, and a small diameter stepped portion is formed at one end on the outer peripheral surface in the axial length range where the cam surfaces are not formed, and at the other end. a hollow armature rotating shaft having a flange-shaped stopper portion protruding radially outward on its outer peripheral edge; a cylindrical body press-fitted into the small diameter stepped portion of the armature rotating shaft and having a rotation-stopping rolled portion formed on its outer peripheral surface; and a DC motor including an armature core press-fitted onto the outer circumferential surface of the cylindrical body that is fitted onto the outer circumferential surface of the armature rotating shaft and continuous with the outer circumferential surface of the armature rotating shaft, and the cam surface is formed. a tubular inner inserted and supported within the armature rotating shaft at an axial length;
A roller and a pressing spring respectively arranged in a wedge-shaped space defined by the outer circumferential surface of the inner and the cam surface, an output rotating shaft slidably spline-fitted inside the inner, and the direct current An engine starter comprising an electromagnetic switch device that simultaneously energizes an electric motor and slides the output rotating shaft. (2) The engine starter according to claim 1, wherein the armature rotating shaft is formed by surface treatment such as carburizing and quenching. (3) The armature core is made up of a large number of disks assembled in the axial direction, and each of the disks is semi-punched to form a concave portion on one surface and a convex portion on the other surface corresponding to the concave portion. An engine starter according to claim 1 or 2, which has a locking portion and is assembled by fitting the locking portions together.