JPH09327147A - Electric rotating machine - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an electric rotating machine (a starter) which is low-cost and which can obtain a rustproof effect and a waterproof effect. SOLUTION: A yoke 9 which is used also as a magnetic frame constitutes the outer frame of a starter 1 together with a housing 13 and an end frame 8 which are arranged on both sides in the axial direction of the yoke 9. In this case, outside diameters D2 , D3 in side end parts of the yoke 9 of the housing 13 and the end frame 8 are formed to be a little larger than the outside diameter D1 of the yoke 9, and a thin-wall cylindrical member 14 is fitted to the outer circumference of the yoke 9. The cylindrical member 14 is made of, e.g. resin. After it has been fitted to the outer circumference of the yoke 9, it is tightened by a bolt in a state that both edges in its axial direction are brought into contact with the respective side edges of the yoke 9 of the housing 13 and the end frame 8. Thereby, the cylindrical member is sandwiched and held between the housing 13 and the end frame 8 while it is being compressed in the axial direction.

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention relates to a rotating electric machine,
In particular, it relates to the rustproof and waterproof structure of rotating electric machines.

[0002]

2. Description of the Related Art The outer frame of a rotary electric machine such as a DC motor is usually composed of a yoke which also serves as a magnetic frame, and front and rear brackets which are arranged on both sides of the yoke in the axial direction to sandwich the yoke. In such a rotary electric machine, since the yoke that also serves as the magnetic frame is formed of a mild steel plate, the yoke must be rust-proofed (there is no problem because the bracket is generally made of an aluminum alloy). In view of this, conventionally, the yoke has been assembled separately, or after the yoke and both brackets have been assembled, the outer peripheral surface has been painted.

[0003]

However, in order to improve the heat resistance of the rotating electric machine, it is necessary to use an epoxy heat-drying type paint because the coating film of the naturally drying type paint melts due to heat. As a result, the coating material cost, the processing cost, and the equipment cost were required. Further, in a model requiring waterproofness, it is necessary to interpose a gasket or a rubber packing between the yoke and each bracket, and there is a problem that the cost is further increased. In addition, actual Kaihei 3-80
Japanese Patent Laid-Open No. 63-63 discloses a plan to mount an annular elastic member so as to cover a divided portion of a frame body divided in the axial direction. However, in this case, it is usual that the outer diameter of the yoke and the outer diameter of the front and rear brackets are considerably different from each other due to a difference in manufacturing method of the yoke and the bracket, and a difference of about 1 to 2 mm usually occurs. Therefore, the elastic member mounted across the yoke and the bracket having different outer diameters needs to be extremely elastic, and the material is limited to a special rubber-based material, which causes a problem of high cost. . Also,
Even in the assembling, there is a problem that the inner diameter of the elastic member is smaller than the outer diameter of the yoke, that is, it is necessary to provide a tightening margin, which makes it extremely difficult to assemble. The present invention has been made based on the above circumstances, and an object thereof is to provide a rotary electric machine that can obtain rust prevention and waterproof effects at low cost.

[0004]

According to the means of solving the problems, according to the first aspect of the present invention, since the cylindrical body having rust resistance is fitted on the outer periphery of the yoke, the outer peripheral surface of the yoke is coated as a rust preventive treatment. Even without it, you can achieve rust prevention of the yoke. For this reason,
In the present invention, only the cost of parts required for the tubular body is required, and the assembly of the tubular body and the yoke is easy. Therefore, the coating cost, the processing cost, and the equipment cost required for the method of coating the outer peripheral surface of the yoke. Compared with, the cost can be reduced considerably. Further, as compared with the case where an elastic member made of a special rubber-based material is used, the assembly is extremely easy and the cost is advantageous (cheap).

According to the second aspect of the present invention, at both axial ends of the tubular body, at least a portion above the horizontal line passing through the central axis of the yoke is abutted against the yoke side end surface of the bracket when mounted on the vehicle. Therefore, it is possible to obtain the waterproof effect of the mating surface between the yoke and the bracket against rainwater and the like falling from above without using a gasket or packing.

According to the third aspect of the present invention, both axial end portions of the tubular body are provided in a shape in which the radial plate thickness gradually decreases toward the tip. As a result, when an axial tightening force is applied between both brackets sandwiching the tubular body, the tubular part can be tightened with a lower fastening force than when the end portion of the tubular body has a constant plate thickness. Since the end portions are deformed, it is possible to suppress an increase in tightening force for tightening and fixing the yoke and both brackets. Further, since the adhesion of the bracket to the end surface of the bracket on the yoke side is improved by the deformation of the end portion of the tubular body, the waterproof effect can be enhanced.

According to the means of claim 4, both end portions in the axial direction of the tubular body are provided in an arcuate sectional shape. As a result, similar to the effect of the means of claim 2, when an axial tightening force is applied between both brackets with the tubular body sandwiched, the end of the tubular body has a constant plate thickness as compared to the case where the tubular body has a constant plate thickness. Since the end portion of the tubular portion is deformed with a lower tightening force, it is possible to suppress an increase in the tightening force for tightening and fixing the yoke and both brackets. Further, since the adhesion of the bracket to the end surface of the bracket on the yoke side is improved by the deformation of the end portion of the tubular body, the waterproof effect can be enhanced.

According to the means of claim 5, the bellows-like uneven portion is provided on at least a part of the cylindrical body in the axial direction.
As a result, when an axial tightening force is applied between the brackets with the tubular body sandwiched between them, the bellows-shaped uneven portion can be contracted (compressed) in the axial direction. Compared with, it is possible to suppress an increase in the tightening force for tightening and fixing the yoke and both brackets. Further, the reaction force generated in the uneven portion compressed in the axial direction improves the adhesion between the axial end surface of the tubular body and the yoke side end surface of the bracket, so that the waterproof effect can be enhanced.

According to the means of claim 6, the tubular portion provided in the tubular body communicates the inside and outside of the outer frame through the ventilation hole formed in the yoke. Thereby, the tubular portion can be used as a ventilation pipe without newly increasing the number of parts.

According to the means of claims 7 to 9, the rotary electric machine of the present invention is applied to a starter. It can be said that obtaining the rust-preventing and waterproofing effects by the tubular body has great merit for a starter that is highly likely to be exposed to water when the vehicle is traveling or when the vehicle is washed.

[0011]

BEST MODE FOR CARRYING OUT THE INVENTION Next, a rotating electric machine of the present invention will be described with reference to the drawings. (First Embodiment) In this embodiment, a rotating electric machine is applied to a starter. The starter 1 includes a starter motor 2 that generates a rotational force when energized, an output shaft 3 that rotates by transmitting the rotational force of the starter motor 2, a pinion 4 that is fitted to the output shaft 3, and a rotation of the starter motor 2. A planetary gear speed reducer (to be described later) that reduces the speed, a one-way clutch (not shown) that transmits the rotation reduced by the speed reducer to the output shaft 3,
A rotation restricting member 5 that restricts the rotation of the pinion 4 at the time of starting,
And a magnet switch 6 arranged on the side opposite to the pinion 4 of the starting motor 2. In the starter 1 of this embodiment, a starter motor 2, a speed reducer, and a magnet switch 6 are arranged in series in the axial direction, and a battery connection terminal 7 covers an outer periphery of the magnet switch 6. Since it is taken out from the end surface of the starter 1 in the axial direction, there is no protrusion of terminals or the like on the outer circumference in the radial direction of the starter 1, and the starter 1 has a substantially cylindrical shape.

The starting motor 2 includes a yoke 9 and a fixed magnetic pole 1.
0, armature 11, brush 12 and the like. The yoke 9 is formed, for example, by press molding (deep drawing) a plate material made of mild steel into a cylindrical shape with a bottom that is open only on one end side (the right side in FIG. 1), and housings arranged on both axial sides of the yoke 9. Starter 1 with 13 and end frame 8
Constitutes the outer frame of. However, the housing 13 and the end frame 8 have outer diameters D2 and D at the ends on the yoke 9 side, respectively.
3 (may be D2 = D3) is formed slightly larger than the outer diameter D1 of the yoke 9, and the outer circumference of the yoke 9 is substantially equivalent to the step between the outer peripheral surface of the yoke 9 and the outer peripheral surfaces of the housing 13 and the end frame 8. Cylindrical member 14 having a thickness (described below)
Are fitted. The bottom surface provided on the other end side of the yoke 9 is bent inward in the radial direction so that the armature 1
It is provided as a partition plate 15 that separates 1 from the speed reducer.

The fixed magnetic pole 10 is composed of a plurality of permanent magnets, for example, and is fixed to the inner peripheral surface of the yoke 9 to form a magnetic field. Instead of the permanent magnet, the fixed magnetic pole 10 in which a field coil and a pole core are combined may be used. The armature 11 has a rotating shaft 1 whose both ends are rotatably supported.
6, armature core 1 provided on the outer periphery of the rotary shaft 16
7. Armature coil 18 wound around this armature core 17
Etc., and one end side of the armature coil 18 is configured as a commutator 19. The brush 12 is a positive electrode brush 12a.
And a negative electrode brush 12b, each of which is held by a holder 20 disposed on one end side of the yoke 9 and has a spring 21
Is pressed against the commutator 19 from the axial direction. However,
The positive electrode brush 12 a is the insulating cylinder 2 housed in the holder 20.
2 (for example, made of resin), the holder 20 made of metal
And is electrically insulated. On the other hand, the negative electrode brush 12b
Are directly held by the holder 20. The holder 2
0 has an outer diameter D1 that is substantially the same as that of the yoke 9, and its outer peripheral portion is sandwiched between the yoke 9 and the end frame 8.

The above-mentioned cylindrical member 14 is made of resin (for example, nylon containing glass fiber) and has corrosion resistance. After being fitted on the outer circumference of the yoke 9 and the holder 20, both axial end surfaces of the cylindrical member 14 are the housing 13 and the end frame. 8, the yoke 9 and the holder 2
It is sandwiched between the housing 13 and the end frame 8 together with 0. However, cylindrical member 1 before tightening with bolts
The axial length of 4 is set to be slightly longer than the total axial length of the yoke 9 and the holder 20, and is tightened in the axial direction to be compressed and contracted in the housing 1.
It is sandwiched between 3 and the end frame 8.

The output shaft 3 is a rotary shaft 16 of the armature 11.
It is arranged coaxially with and is rotatably supported by the housing 13. A helical spline 3a is provided on the outer circumference of the output shaft 3.
And a stop collar 23 for restricting the forward movement of the pinion 4 is provided on the other end side of the helical spline 3a. The pinion 4 is fitted on the helical spline 3 a so that the helical spline 3 is mounted on the output shaft 3.
It is provided so as to be able to move forward and backward along a and meshes with a ring gear (not shown) of the engine to transmit the rotational force of the starting motor 2. A rotation regulating plate 24 having an outer diameter larger than that of the pinion 4 is integrally provided on one end side of the pinion 4. A large number of engagement grooves 24 a along the axial direction are formed on the outer periphery of the rotation restricting plate 24 at equal intervals in the circumferential direction of the rotation restricting plate 24. In addition, this pinion 4
Is urged toward the starting motor 2 (to the right in FIG. 1) by a spring 25 arranged on the other end side of the pinion 4.

The speed reducer comprises a sun gear 26 formed on the outer periphery of the tip of the rotary shaft 16, a plurality of planet gears 27 meshing with the sun gear 26, and an internal gear 28 meshing with each planet gear 27. The sun gear 26 is the rotary shaft 1.
By rotating integrally with 6, the rotation of the rotating shaft 16 is transmitted to each planetary gear 27. The planetary gears 27 are rotatably supported by pins 29 fixed to the outer (not shown) of the one-way clutch via bearings 30. The planetary gears 27 mesh with the sun gears 26 and the internal gears 28 while rotating to rotate the outer periphery of the sun gears 26. Revolve around. The rotation of the internal gear 28 is restricted by the housing 13, so that the sun gear 26 can rotate.

The one-way clutch is composed of the outer member, an inner member (not shown) integrally formed with the output shaft 3, a roller (not shown) interposed between the outer member and the inner member, and the like.
The rotation reduced by the reduction gear (revolution of the planetary gear 27) is transmitted from the outer through the roller to the inner.

The rotation restricting member 5 is a spring member provided by winding a rod-shaped metal material, and both ends thereof are bent and bent substantially at right angles in the same direction at positions facing each other in the radial direction. The bent and bent one end portion 5a is a restriction rod that restricts rotation of the pinion 4 by engaging with an engagement groove 24a formed on the outer peripheral surface of the rotation restriction plate 24. Also, the other end 5b has
The magnet switch 6 via the cord-shaped member 31 such as a wire
Is transmitted. Of course, instead of the string-like member 31, a crank bar or the like may be used for transmission.

The rotation restricting member 5 is held so as to be movable in the vertical direction (vertical direction in FIG. 1) with the housing 13 being restricted from moving in the axial direction (horizontal direction in FIG. 1). . The rotation restricting member 5 is constantly urged upward by a return spring (not shown), and the operation of the magnet switch 6 via the string-shaped member 31 causes the other end 5b to operate.
To the magnet switch 6 when the rotation restricting member 5 is moved downward against the spring force of the return spring.
When is turned off, the spring force of the return spring urges it upward to return to the initial position (the position shown in FIG. 1).

The magnet switch 6 is held by a resin pedestal 32 press-fitted into the holder 20, and is arranged so that the movement direction of the plunger 33 intersects with the rotation shaft 16 (vertical direction in FIG. 1). There is. When a starter switch (not shown) is turned on and a built-in coil (not shown) is energized, the magnet switch 6 attracts the plunger 33 by the magnetic force generated in the coil.
As a result, the contacts (not shown) of the motor circuit provided inside the switch are closed to energize the starting motor 2, and at the same time, the rotation restricting member 5 is driven via the string-like member 31. One end of the string-shaped member 31 is locked to the bottom surface of the plunger 33, the other end is locked to the other end 5b of the rotation restricting member 5, and is held by the roller 34 held by the pedestal 32 and the housing 13. Plunger 3 via roller 35
The operation of 3 is transmitted to the rotation restricting member 5.

Next, the operation of this embodiment will be described. When the starter switch is turned on and the magnet switch 6 is activated, the cord-shaped member 31 is moved along with the movement of the plunger 33.
Is pulled toward the magnet switch 6 side,
The entire rotation restricting member 5 moves downward. As a result, one end 5a of the rotation restricting member 5 (hereinafter referred to as the restricting rod 5a) engages with the engagement groove 24a of the rotation restricting plate 24 to restrict the rotation of the pinion 4.

On the other hand, when the magnet switch 6 is actuated to close the contacts of the starting motor 2 and energize the armature 11, a rotational force is generated in the armature 11. The rotational force of the armature 11 is reduced by the reduction gear and then transmitted to the output shaft 3 via the one-way clutch. As a result, the output shaft 3 rotates and the pinion 4 also tries to rotate. However, since the rotation of the pinion 4 is restricted by the restriction rod 5a, the rotational force of the output shaft 3 is reduced by the action of the helical spline 3a. Is the thrust that pushes out in the axial direction. As a result, the pinion 4 can move forward on the output shaft 3 and engage with the ring gear. When the pinion 4 meshes with the ring gear, the tip of the restriction rod 5a is disengaged from the engagement groove 24a of the rotation restriction plate 24 and falls into one end of the rotation restriction plate 24, whereby the rotation restriction of the pinion 4 is released. As a result, the rotational force of the output shaft 3 is transmitted from the pinion 4 to the ring gear, and the engine starts.

When the pinion 4 moves forward and meshes with the ring gear, the urging force of the spring 25 for urging the pinion 4 increases. Further, when the pinion 4 is rotated by the rotational force of the engine after the engine is started, the retracting force is applied to the pinion 4 by the action of the helical spline 3a. As a result, the pinion 4 tries to retreat on the output shaft 3, but the tip end of the regulation rod 5a that has fallen to the one end side of the rotation regulation plate 24 supports the one end side end surface of the rotation regulation plate 24 so that the pinion 4 retreats. Is blocked.
After that, when the starter switch is turned off and the operation of the magnet switch 6 is stopped, the force for pulling the rotation restricting member 5 via the string-shaped member 31 disappears, so that the rotation restricting member 5 is initialized by the spring force of the return spring. Return to position. As a result, the restriction rod 5a that has prevented the retraction of the pinion 4 is disengaged from the rotation restriction plate 24, so that the retraction force acting on the pinion 4 pushes the pinion 4 back to the initial position.

(Effect of this embodiment) Starter 1 of this embodiment
Since the entire outer peripheral surfaces of the yoke 9 and the holder 20 are covered with the cylindrical member 14 made of resin, the rust prevention of the yoke 9 is achieved without coating the outer peripheral surface of the yoke 9 as a rust preventive treatment as in the conventional case. it can. For this reason, in the present embodiment, only the cost of parts required for the cylindrical member 14 is required (in the case of resin, it can be manufactured inexpensively by injection molding), and the assembly of the cylindrical member 14 and the yoke 9 is easy. Compared with the paint cost, treatment cost, and equipment cost required for the method of painting the outer peripheral surface of the yoke 9, a considerable cost reduction can be achieved. Further, even when compared with the case where an elastic member made of a special rubber-based material is used, in this embodiment, the cylindrical member 14 is simply fitted to the outer periphery of the yoke 9 (it is not necessary to press-fit), and the assembly is extremely performed. It is easy and advantageous (cheap) in terms of cost.

Further, since the cylindrical member 14 is pinched between the housing 13 and the end frame 8 while being compressed and contracted in the axial direction by tightening the bolts, both axial end portions of the cylindrical member 14 are formed along the entire circumference of the housing 13 and the end frame 8. It is possible to make close contact with the end surface of the end frame 8 on the side of each yoke 9. As a result, the joint between the cylindrical member 14 and the housing 13 and the end frame 8 is effectively closed, so that the waterproof effect can be obtained without using a gasket or packing.

(Second Embodiment) FIG. 2 is a sectional view showing the end shape of the cylindrical member 14. The cylindrical member 14 of the present embodiment is
As shown in FIG. 2, edge portions 14a whose plate thickness gradually decreases toward the tip are provided at both ends in the axial direction. As a result, when the axial end surfaces of the cylindrical member 14 are abutted against the end surfaces of the housing 13 and the end frame 8 on the side of the respective yokes 9, when the bolts are tightened, the plate thickness becomes the tip as shown in the first embodiment. Since the end portion (edge portion 14a) of the cylindrical member 14 is deformed with a lower tightening force than in the case where the cylindrical member 14 is constant, an increase in the tightening force due to the use of the cylindrical member 14 can be suppressed. Further, similarly to the first embodiment, the deformation of the end portion (edge portion 14a) of the cylindrical member 14 improves the adhesion between the housing 13 and the end surface of the end frame 8 on the side of each yoke 9, thereby improving the waterproof effect. It can also be increased.

(Third Embodiment) FIG. 3 is a sectional view showing the shape of the end portion of the cylindrical member 14. The cylindrical member 14 of the present embodiment is
As shown in FIG. 3, the radial cross-sectional shape of both axial end portions is provided in an arc shape 14b. Thereby, the same operation and effect as those of the second embodiment can be obtained.

(Fourth Embodiment) FIG. 4 is a sectional view showing the shape of the end of the cylindrical member 14. The cylindrical member 14 of the present embodiment is
As shown in FIG. 4, a bellows-shaped uneven portion 14c is provided in at least a part in the axial direction. As a result, when the axial end surfaces of the cylindrical member 14 are abutted against the end surfaces of the housing 13 and the end frame 8 on the side of each yoke 9, the bellows-shaped concave and convex portions 14c contract axially (compression). Therefore, it is possible to suppress an increase in the tightening force for tightening the bolt, as compared with the case where the uneven portion 14c is not provided. Further, the reaction force generated in the uneven portion 14c compressed in the axial direction improves the adhesion between the axial end surfaces of the cylindrical member 14 and the end surfaces of the housing 13 and the end frame 8 on the side of each yoke 9, so that the waterproof effect is obtained. It can also be increased.

(Fifth Embodiment) FIG. 5 is an overall view including a cross section of a main part of the starter 1. The cylindrical member 14 of the present embodiment is a cylindrical ventilation pipe 14d that projects outward in the radial direction.
The (cylindrical portion of the present invention) is integrally provided and arranged in accordance with the ventilation hole 9a formed in the yoke 9. The ventilation pipe 14d has a closed front end, and a pair of holes 14e are formed on both sides of the front end of the ventilation pipe 14d.
The inside and outside of the starter 1 communicate with each other through a.
In this way, by providing the ventilation pipe 14d integrally with the cylindrical member 14, it is not necessary to add new parts to form a ventilation structure.

In each of the above-described embodiments, both axial end portions of the cylindrical member 14 are in contact with the end surfaces of the housing 13 and the end frame 8 on the side of each yoke 9 over the entire circumference.
When the starter 1 is mounted on the vehicle, at least the yoke 9
If both ends in the axial direction of the cylindrical member 14 are in contact with the end surfaces of the housing 13 and the end frame 8 on the yoke 9 side above the horizontal line passing through the axis, the waterproof effect against rainwater and the like falling from above can be obtained. be able to.

[Brief description of drawings]

FIG. 1 is an overall view including a cross section of a main part of a starter (first
Example).

FIG. 2 is a cross-sectional view showing an end shape of a cylindrical member (second
Example).

FIG. 3 is a sectional view showing an end shape of a cylindrical member (third embodiment)
Example).

FIG. 4 is a cross-sectional view showing an end shape of a cylindrical member (fourth shape)
Example).

FIG. 5 is an overall view including a cross section of a main part of a starter (No. 5)
Example).

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Starter (rotary electric machine) 2 Starter motor 3 Output shaft 4 Pinion 8 End frame (bracket) 9 Yoke 9a Vent hole 13 Housing (bracket) 14 Cylindrical member (cylindrical body) 14c Concavo-convex part 14d Ventilation pipe (cylindrical part) 16 Rotation axis (armature shaft)

Claims (9)

[Claims] 1. An outer frame is composed of a cylindrical yoke that also serves as a magnetic frame and both brackets arranged on both sides of the yoke in the axial direction. The bracket has an outer diameter at least at an end portion on the yoke side in the axial direction. A rotary electric machine provided with a diameter larger than the outer diameter of the yoke, wherein a tubular body having corrosion resistance is fitted to the outer periphery of the yoke, and both axial ends of the tubular body are on the yoke side end surface of the bracket. A rotating electric machine, wherein the rotating electric machine is abutted in a pressed state. 2. The cylindrical body is in contact with both end portions in the axial direction in a state where at least a portion above a horizontal line passing through the center axis of the yoke is pressed against the yoke side end surface of the bracket when mounted on a vehicle. The rotary electric machine according to claim 1, wherein: 3. The rotary electric machine according to claim 1, wherein both axial ends of the tubular body are provided in a shape in which the radial plate thickness gradually decreases toward the tip. 4. The rotary electric machine according to claim 1, wherein both end portions in the axial direction of the tubular body are provided with an arcuate cross section in the radial direction. 5. The rotary electric machine according to claim 1, wherein the tubular body has a bellows-shaped uneven portion at least in a part in the axial direction. 6. The tubular body has a hollow tubular portion that projects outward in the radial direction, and the tubular portion is connected to the inner side of the outer frame through a vent hole formed in the yoke. The rotary electric machine according to claim 1, wherein the rotary electric machine communicates with the outside. 7. The rotating electric machine according to claim 1, wherein a starting motor that receives an electric current to generate a rotating force on the armature shaft, and an output shaft that receives the rotating force of the starting motor and rotates. A pinion that is provided to be able to move back and forth on the output shaft and that transmits the rotational force of the starting motor that is transmitted through the output shaft to a ring gear of the engine, and an electromagnetic switch that controls energization of the starting motor are provided. A rotating electric machine characterized by being a starter. 8. The rotating electric machine according to claim 7, wherein the electromagnetic switch is a starter arranged on one axial side of the armature shaft. 9. The rotating electric machine according to claim 8, wherein the rotating electric machine is a starter including a speed reducing unit that reduces the rotation speed of the starting motor and transmits the rotation speed to the output shaft.