JPH1155887A - Electric rotating machine - Google Patents

Abstract

PROBLEM TO BE SOLVED: To shorten the whole length of an electric rotating machine, by miniaturizing its bearing portion. SOLUTION: An electric rotating machine having a commutator attached to a rotational shaft 3 of its armature, an oil retaining bearing 5 for supporting the rotational shaft 3, and a bracket 6 for disposing the bearing 5 therein. In this case, an armature-side-oriented recessed portion 3a in a thrust direction is formed on the bracket side of the rotational shaft 3, and the bracket 6 is made of a material which does not absorb the oil impregnated in the bearin 5 and alter its quality thereby, and a supporting protrusion 6a with a circular hole 6b is formed on the commutator side of the bracket 6, and the bearing 5 is formed out of a cylindrical body with a roundness almost equal to the rotational shaft 3 to couple it to the shaft 3, and the supporting protrusion 6a is disposed in a recessed portion of the commutator to support the bearing 5 coupled to the rotational shaft 3 in the hole 6b of the bracket 6.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

2. Description of the Related Art Generally, a rotating electric machine, for example, a rotating electric machine (motor) 20 of a blower for a vehicle air conditioner, has a stator 23 disposed in a yoke 22 and an armature 2 as shown in FIG.
4, a commutator 25 attached to the output shaft side of the rotating shaft 26 of the armature 24, and a brush holding portion (not shown)
And

An armature 24 is formed by winding a coil 24b around an armature core 24a and rotates integrally with a rotating shaft 26. Both ends of the rotating shaft 26 are bearings 27 (only one is shown). It is rotatably supported by.

[0003] The brush holder is provided with a yoke 2 of the rotary electric machine 20.
2, a brush holder formed on a substrate mounted on the substrate 2, and a commutator 25 held by the brush holder.
And a brush that is in sliding contact with each other.

The rotating electric machine 20 of the blower for a vehicle air conditioner is used by attaching a resin fan. A rotation stopper is formed on the rotating shaft, and the rotation stopper is formed relatively large so that the resin fan mounting part is not destroyed by the load torque during rotation.The diameter of the rotating shaft is also smaller than the size of the rotating electric machine. A large diameter is used for the split.

[0005]

That is, since the rotating electric machine of a blower for a vehicle air conditioner uses a large rotating shaft for its physical size, the bearings are also large and the total length of the rotating electric machine is long. As described above, in the case of a rotating shaft having a large diameter, the diameter of a bearing that receives the rotating shaft necessarily increases. Therefore,
It was difficult to shorten the axis of bearings and the like.

In particular, in the technique employing the centering bearing, the presence of the bearing holding mechanism makes it difficult to install the inside of the commutator, and the bearing portion is completely placed outside the commutator. In addition, in a rotating electric machine in which the commutator has a large outer diameter, when the commutator is increased in diameter, the overall length of the brush is regulated by the motor outer diameter, so the brush length is shortened and the life of the rotating electric machine is shortened. There is an inconvenience.

Therefore, a technology in which a bearing portion is provided inside a commutator is known (Japanese Utility Model Laid-Open No. 2-57251 and Japanese Utility Model Laid-Open No. 3-30784). However, the above-mentioned 2-57
In the technology proposed in JP-A-251-301 and JP-A-3-30784, the rotating electric machine itself becomes considerably large, the thickness of the sleeve bearing is reduced, the bearing life is reduced, and the thickness of the rear bracket is reduced. Is likely to decrease in strength.

Therefore, it is conceivable to make the rotating shaft narrow only in the bearing portion as shown in FIG. 9. However, in this technique, since the surface pressure applied to the bearing increases, it is necessary to extend the bearing in the axial direction as a countermeasure. Therefore, it is difficult to shorten the axis of a bearing or the like.

An object of the present invention is to reduce the overall length of a rotating electric machine by reducing the size of a bearing portion.

[0010]

According to the first aspect of the present invention, there is provided a rotating shaft of an armature, a commutator mounted on the rotating shaft, an oil-impregnated bearing for supporting the rotating shaft, and the bearing. And a bracket in which a recess in the thrust direction toward the armature side is formed on the bracket side of the commutator, and the bracket is formed from a material that does not absorb and deteriorate the impregnating oil. And a support protrusion on the commutator side having a circular hole is formed. The bearing is formed of a cylindrical body having a roundness equivalent to that of a rotating shaft, and is connected to the rotating shaft. The present invention is solved by a configuration in which a bearing disposed in a recess of a child and connected to the rotating shaft is supported by a hole of the bracket.

According to the above configuration, even if the outer diameter of the commutator is small, the bearing portion can be arranged in the commutator, and the rotating electric machine can be shortened. In addition, since the bracket is provided with a support protrusion, the housing of the rotating electric machine can be strengthened.
It can also be made of resin.

Generally, in a bearing in which a sintered metal is impregnated with lubricating oil, impregnating oil oozes from the inside of the bearing by the surface pressure applied from the rotating shaft, and the rotating shaft is fluid-lubricated. Since the oil is added in the direction in which the oil oozes out, it becomes possible to lubricate the rotating shaft faster than in the conventional structure. Also, in the prior art, the bearing is ring-shaped, so assembling requires the accuracy of the inner and outer diameters, but according to the present invention, the bearing only requires the accuracy of the outer diameter regardless of the inner diameter. In addition, manufacturing control becomes easy.

At this time, a recess in the thrust direction is formed at the end of the rotating shaft, and the bearing is connected in the recess, so that the shaft can be further shortened.

[0014] Further, the concave portion in which the rotating shaft is formed has a concave bottom surface formed in a spherical shape, and the bearing has a spherical convex portion movably fitted in the spherical concave portion. By rotating the shaft, a centering function can be performed between the rotating shaft and the bearing.

Further, by forming the diameter of the rotating shaft larger than the diameter of the bearing, a load in the axial direction (thrust direction) can be received at the end of the support projection of the bracket. Can be reduced.

Further, if the end of the bearing on the commutator side is formed so as to have a diameter larger than that of the rotating shaft and a recess for fitting the rotating shaft is formed, the rotating shaft is fixed to the bearing portion. Eliminates the need for drilling holes.

A bearing is fixed to the bracket, a recess in the thrust direction is formed at an end of the rotating shaft, and the bearing is configured to slide inside the recess of the rotating shaft, whereby the bearing is fixed. However, the rotating shaft slides between the concave portion and the bearing disposed in the concave portion by fluid lubrication with oil oozing out from the bearing.

According to a seventh aspect of the present invention, there is provided a rotating electric machine including a rotating shaft of an armature, a commutator mounted on the rotating shaft, and a bracket for supporting the rotating shaft. A recess is formed in the thrust direction on the bracket side of the commutator, and the bracket is formed of a material that does not absorb and deteriorate impregnating oil and has a support protrusion on the commutator side having a circular hole, This problem is solved by forming the entire rotating shaft from a material capable of forming an oil-impregnated bearing, arranging the support protrusions in recesses of the commutator, and supporting the rotating shaft in holes of the bracket. With the configuration as in the present example, there is no need to connect the rotating shaft and the bearing.

[0019]

DESCRIPTION OF THE PREFERRED EMBODIMENTS One embodiment of the present invention will be described below with reference to the drawings. The members, arrangements, and the like described below do not limit the present invention, and can be variously modified within the scope of the present invention.

(Embodiment 1) FIGS. 1 and 2 show a first embodiment of a rotating electric machine according to the present invention. FIG. 1 is a schematic sectional view of the rotating electric machine, and FIG. It is an expanded sectional explanatory view of a bearing part. The rotating electric machine 1 in this example is used for the same application as that of the above-described conventional example,
An armature 2, a rotating shaft 3, a commutator 4, an oil-impregnated bearing (bearing) 5, a bracket 6, and a stator 7 are main components, and the armature 2 is an armature core 2a.
The armature 2 is integrated with the rotating shaft 3. A commutator 4 is provided on the output side of the rotating shaft 3. The commutator 4 of the present embodiment has a recess 4a in the thrust direction toward the armature 2 side. In this example, other configurations other than those related to the bearing and the rotating shaft are the same as those of the related art.

The bracket 6 of the present embodiment is formed of a material that does not absorb impregnating oil or deteriorates, and has a support protrusion 6a directed to the commutator 4 side. The support projection 6a is provided with a circular hole 6b for rotatably supporting the bearing 5 described below. Bracket 6 of this example
The hole 6b is formed by burring in order to reduce the surface pressure applied to the bearing 5, but may be formed by using a molded part as long as the material does not absorb impregnating oil or deteriorate.

The bearing 5 of this embodiment is formed of a cylindrical body having a roundness equivalent to that of a conventional shaft, and is connected to the rotating shaft 3 of the armature 2. As shown in FIG. 2, the connection between the bearing 5 and the rotating shaft 3 of this embodiment is such that a fitting recess 3 a is formed in the rotating shaft 3, and the bearing 5 is fitted into the fitting recess 3 a. Protrusions 5a are formed, and these are connected by press-fitting.

As shown in FIG. 1, the support projection 6a of the bracket 6 is disposed in the recess 4a formed in the commutator 4, and the bearing 5 connected to the rotary shaft 3 is supported by the hole of the bracket 6. It is arranged so that.

(Embodiment 2) FIG. 3 is an enlarged sectional explanatory view similar to FIG. 2 showing a second embodiment of the present invention. In the following embodiments, the same members and the like as those in the above embodiment are denoted by the same reference numerals, and detailed description thereof will be omitted. In the present embodiment, the embodiment shown in FIGS. 1 and 2 is different from the embodiment shown in FIGS. 1 and 2 in that the diameter of the rotating shaft 3 is larger and the washer 8 is provided between the rotating shaft 3 and the end of the support protrusion 6 a of the bracket 6. (8a, 8
b). That is, the bearing 5 and the rotating shaft 3 are connected in the same manner as in the above embodiment, but the washers 8a, 8 are provided between the rotating shaft 3 and the end of the support projection 6a of the bracket 6.
Since b is formed, a load in the axial direction (thrust direction) of the rotating shaft 3 can be received at the end of the support protrusion 6 a of the bracket 6.

(Embodiment 3) FIG. 4 is an enlarged sectional explanatory view showing a third embodiment of the present invention. In the present embodiment, in order to connect the bearing 5 and the rotating shaft 3, the bearing 5 is not formed to be thin as in the above-described embodiment, but the bearing 5 and the rotating shaft 3 have the same diameter. 3 is configured such that the outer diameter of the recess 3 a is substantially the same as the outer diameter of the bearing 5. With the configuration as in this example, the bearing 5 becomes a cylindrical body having a uniform diameter, so that the direction of assembly for connection to the rotating shaft 3 is eliminated, and assembly is facilitated.

(Embodiment 4) FIG. 5 is an enlarged sectional explanatory view showing a fourth embodiment of the present invention. In this example, the bottom surface of the concave portion 3a formed on the rotating shaft 3 is formed in a spherical shape.
The fitting convex portion side of the bearing 5 is formed as a spherical convex portion 5a so as to movably fit into the spherical concave portion 3a. With this configuration, when the rotating shaft 3 rotates, a centering function can be performed with the bearing 5.

(Embodiment 5) FIG. 6 is an enlarged sectional explanatory view showing a fifth embodiment of the present invention. In this example, FIG.
2 shows an example in which the entire rotating shaft is made of a material that forms an oil-impregnated bearing in the embodiment shown in FIG. That is, the bracket 6 of this embodiment is made of a material that does not absorb and deteriorate the impregnated oil, and the entire rotating shaft 3 is made of a material that can form an oil-impregnated bearing.
And the rotating shaft 3 is supported by the hole 6 b of the bracket 6. With such a configuration, the connection between the rotating shaft 3 and the bearing 5 becomes unnecessary.

That is, the rotating electric machine 1 in this embodiment has a rotating shaft including the rotating shaft 3 of the armature 2, a commutator 4 attached to the rotating shaft 3, and a bracket 6 for supporting the rotating shaft 3. In the electric machine 1, a recess 4 a is formed in the thrust direction on the bracket 6 side of the commutator 4, and the bracket 6 is formed of a material that does not absorb and deteriorate impregnated oil and has a circular hole 6 b. Side support protrusion 6a
The rotation shaft 3 is entirely formed of a material capable of forming the oil-impregnated bearing 5, the support protrusion 6 a is disposed in the recess 4 a of the commutator 4, and the rotation shaft 3 is supported by the hole 6 b of the bracket 6. It is configured to be.

(Embodiment 6) FIG. 7 is an enlarged sectional explanatory view showing a sixth embodiment of the present invention. In the present example, the coupling between the rotating shaft 3 and the bearing 5 is configured such that no recess is formed in the rotating shaft 3. That is, a large-diameter portion 9 having a larger diameter than the rotating shaft 3 is formed at the end of the bearing 5 on the commutator 4 side. A concave portion 9a for fitting the rotary shaft 3 is formed in the large diameter portion 9 larger than the rotary shaft 3, and the rotary shaft 3 and the bearing 5 are connected by fitting the rotary shaft 3 into the concave portion 9a. Let it. With the configuration as in this example, it is not necessary to drill a hole in the rotating shaft 3 to fix the bearing 5.

(Embodiment 7) FIG. 8 is an enlarged sectional explanatory view showing a seventh embodiment of the present invention. In this embodiment, the bracket 6 and the bearing 5 are fixed in the embodiment shown in FIG. Then, a recess 3 a in the thrust direction toward the armature 2 is formed at the end of the rotating shaft 3. And bearing 5
Is arranged inside the concave portion 3 a of the rotating shaft 3. As a result, the bearing 5 is fixed, but the rotating shaft 3 slides between the concave portion 3a and the bearing 5 disposed in the concave portion 3a by fluid lubrication with oil oozing out from the bearing 5.

[0031]

As described above, according to the first aspect of the present invention, even if the outer diameter of the commutator is small, the bearing portion can be arranged in the commutator and the rotating electric machine can be shortened. In addition, since the bracket is provided with the support protrusion, the housing of the rotating electric machine can be strengthened, so that the bracket can be made of resin. Further, according to the above configuration, the centrifugal force is also applied in a direction in which the impregnating oil is oozed out, so that the rotating shaft can be lubricated more quickly than in the conventional structure. In addition, the bearing only requires accuracy of the outer diameter irrespective of the inner diameter, which facilitates production management.

At this time, a recess in the thrust direction is formed at the end of the rotating shaft, and the bearing is connected in the recess, so that the shaft can be further shortened. Further, if the concave portion in which the rotating shaft is formed is formed such that the concave portion bottom surface is formed in a spherical shape and the bearing is formed with a spherical convex portion movably fitted in the spherical concave portion, the rotating shaft rotates. Thus, a centering function can be performed between the rotating shaft and the bearing.

When the diameter of the rotating shaft is larger than the diameter of the bearing, a load in the axial direction (thrust direction) can be received at the end of the support projection of the bracket. Can be reduced. When the end of the bearing on the side of the commutator 4 is formed so as to have a diameter larger than that of the rotary shaft and to have a recess for fitting the rotary shaft, the bearing is fixed to the rotary shaft. No drilling is required.

Then, a bearing is fixed to the bracket, and a recess in the thrust direction is formed at an end of the rotating shaft, and the bearing is configured to slide inside the recess of the rotating shaft, whereby the bearing is fixed. However, the rotating shaft slides between the concave portion and the bearing disposed in the concave portion by fluid lubrication with oil oozing out from the bearing.

The bracket is formed of a material which does not absorb and deteriorate the impregnated oil, has a commutator-side support projection having a circular hole, and the entire rotating shaft is formed of a material capable of forming an oil-impregnated bearing. Since the projection is arranged in the concave portion of the commutator 4 and the rotating shaft is supported by the hole of the bracket, the connection between the rotating shaft and the bearing is not required.

[Brief description of the drawings]

FIG. 1 is a schematic sectional view showing an embodiment of a rotating electric machine according to the present invention.

FIG. 2 is an enlarged sectional explanatory view of a bearing part of FIG. 1;

FIG. 3 is an enlarged sectional explanatory view similar to FIG. 2 showing another embodiment.

FIG. 4 is an enlarged sectional explanatory view showing still another embodiment.

FIG. 5 is an enlarged sectional explanatory view showing another embodiment.

FIG. 6 is an enlarged sectional explanatory view showing still another embodiment.

FIG. 7 is an enlarged sectional explanatory view showing another embodiment.

FIG. 8 is an enlarged sectional explanatory view showing another embodiment.

FIG. 9 is an enlarged sectional explanatory view showing a conventional example.

[Explanation of symbols]

 Reference Signs List 1 rotating electric machine 2a armature core 2b coil 2 armature 3 rotating shaft 3a fitting concave portion 4 commutator 4a thrust direction concave portion 5a fitting convex portion 5 oil-impregnated bearing (bearing) 6 bracket 7 stator 6a support protrusion 6b hole

Claims (7)

[Claims] 1. A rotating shaft of an armature, a commutator mounted on the rotating shaft, an oil-impregnated bearing for supporting the rotating shaft,
A bracket in which the bearing is disposed, wherein the commutator is formed on the bracket side thereof with a recess in the thrust direction toward the armature side, and the bracket does not absorb and deteriorate the impregnating oil. A support projection formed on the commutator side having a circular hole formed of a material; the bearing is formed of a cylindrical body having a roundness equivalent to that of a rotating shaft, and is connected to the rotating shaft; Is disposed in a recess of the commutator, and a bearing connected to the rotating shaft is supported by a hole in the bracket. 2. The rotating electric machine according to claim 1, wherein a recess in a thrust direction is formed at an end of the rotating shaft, and the bearing is connected in the recess. 3. The concave portion in which the rotary shaft is formed, the concave portion has a spherical bottom surface, and the bearing has a spherical convex portion movably fitted in the spherical concave portion. Item 3. The rotating electric machine according to item 1 or 2. 4. The rotating electric machine according to claim 1, wherein a diameter of said rotating shaft is formed larger than a diameter of said bearing. 5. The end of the bearing on the commutator side having a diameter larger than that of the rotary shaft and a concave portion for fitting the rotary shaft is formed. Rotating electric machine. 6. The bearing according to claim 1, wherein a bearing is fixed to said bracket, a recess in the thrust direction is formed at an end of said rotating shaft, and said bearing slides inside said recessed portion of said rotating shaft. Rotary electric machine. 7. A rotating electrical machine comprising: a rotating shaft of an armature; a commutator attached to the rotating shaft; and a bracket for supporting the rotating shaft, wherein a thrust is provided on a bracket side of the commutator. The bracket is made of a material that does not absorb and deteriorate the impregnated oil, has a commutator-side support protrusion having a circular hole, and is formed of a material that can form an oil-impregnated bearing. The rotating electric machine, wherein the support protrusion is disposed in a recess of the commutator, and the rotating shaft is supported by a hole of the bracket.