JPH09219951A - Bearing device for motor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a bearing device capable of obtaining stable, low aligning torque. SOLUTION: A receiving portion 3 supporting one of the outer periphery of a bearing 2 is provided, a leaf spring 12 providing a plurality of supporting pieces 10 supporting the other of the outer periphery of the bearing 2 is attached through a plurality of legs 9 and bent portions 11 within a cylindrical bearing case 8 having a different level portion 4 with the diameter larger than the receiving portion 3, and the bent portions 11 of the leaf spring 12 is linked to a corner 15 of the different level portion 4 of a bearing case 8. Thereafter, a curl bent portion 13 is provided by curl processing at an open end portion of the bearing case 8. By doing this, the leaf spring 12 does not move during curl processing by the linkage between the bent portion 11 and different level portion 4, a pushing pressure of the supporting piece 10 against the bearing 2 becomes constant, and stable low aligning torque can be obtained.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a bearing device for an electric motor provided with a bearing made of a sintered oil-impregnated alloy.

[0002]

2. Description of the Related Art In recent years, with the spread of electric products, the number of electric products using electric motors has increased, and there has been an increasing demand for bearing devices for electric motors that do not require refueling.

Conventionally, as a bearing device for this type of electric motor, for example, there is one disclosed in Japanese Utility Model Laid-Open No. 63-668.
The configuration will be described below with reference to FIG.

As shown in the figure, a sintered oil-impregnated alloy bearing 102 for supporting a rotating shaft 101 of an electric motor, and this bearing 10
2, a bearing case 105 that is supported concentrically inside and is fixed by inserting the outer diameter surface into the end surface opening 104 of the motor housing 103, and the bearing 102 housed inside the bearing case 105 and the rotating shaft A leaf spring 106 that presses in the 101 direction and an oil-absorbent fiber material 107 impregnated with lubricating oil that is housed in at least both end surface positions of the bearing 102 inside the bearing case 105 in the rotating shaft 101 direction are provided.

[0005]

According to such a conventional bearing device for an electric motor, the leaf spring 106 is provided in the bearing case 10.
5, a space 108 is formed between the bearing case 105 and the bearing case 105 in the direction of the rotating shaft 101 only by contacting the inner surface of the leaf spring 1.
When processing the curl portion 109 formed so as to hold 06, the tip end portion of the leaf spring 106 is pressed and moves in the axial direction, and the spring pressure of the leaf spring 106 that supports the bearing 102 changes to various magnitudes. There was a problem that variation in core torque was large and it was difficult to obtain stable low centering torque.

The present invention solves the above problems, and an object of the present invention is to provide a bearing device for an electric motor that can obtain a stable low centering torque.

[0007]

In a bearing device for an electric motor of the present invention, a bearing made of a sintered oil-impregnated alloy in which a spherical arc surface is formed on the outer circumference for supporting the rotor shaft of the electric motor, and the outer circumference of the bearing. A bearing case that has a receiving portion that supports one of the two, and that has a stepped portion that is larger in diameter than the receiving portion and that forms a cylindrical spring accommodating portion that fits into the housing of the electric motor; A leaf spring having a plurality of legs housed in a housing portion and a plurality of supporting pieces connected to the leg and supporting the other of the outer circumferences of the bearings inside the leg via bent portions, and a support for the leaf spring. A curl bending portion provided at the open end of the spring accommodating portion of the bearing case so as to hold the end of one piece, and a lubricating oil that is stored in the spring accommodating portion and contacts a part of the outer circumference of the bearing. Oil-absorbent fiber material, and the bent portion of the leaf spring is It is obtained by a structure which engages the corner of the stepped portion of the receiving case.

According to the present invention, it is possible to provide a bearing device for an electric motor that can obtain a stable low centering torque.

[0009]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The invention according to claim 1 of the present invention is a bearing made of a sintered oil-impregnated alloy in which a spherical arc surface is formed on the outer periphery for supporting the rotor shaft of an electric motor, and the outer periphery of this bearing. A bearing case that has a receiving portion that supports one of the two, and that has a stepped portion that is larger in diameter than the receiving portion and that forms a cylindrical spring accommodating portion that fits into the housing of the electric motor; A leaf spring in which a plurality of legs housed in the housing portion and a plurality of support pieces connected to the leg and supporting the other of the outer circumferences of the bearings inside the leg are formed via bent portions, and a support piece of the leaf spring. The curl bending portion provided at the open end of the spring accommodating portion of the bearing case so as to hold the end of the bearing case, and impregnated with the lubricating oil that is accommodated in the spring accommodating portion and contacts a part of the outer periphery of the bearing. Oil-absorbent fiber material, and the bent portion of the leaf spring is provided in the bearing case. It is configured to engage with the corner of the step portion, and even if pressure is applied to the tip of the leg of the leaf spring when processing the curl bending portion at the opening end of the bearing case, the leaf spring will not Since the leaf spring comes into contact with the corner to prevent movement, the radial force of the leaf spring acts on the supporting portion with the corner coming into contact as a fulcrum to hold the bearing.
The change in the centering force of the leaf spring is small, stable centering torque is obtained, and low centering torque optimal for a bearing device used for a small electric motor or the like is obtained.

Hereinafter, an embodiment of the present invention will be described with reference to FIG.
This will be described with reference to FIGS. (Embodiment 1) As shown in FIGS. 1 to 3, one of the outer circumferences of a sintered oil-impregnated alloy bearing 2 in which a spherical arc surface is formed on the outer circumference that supports a rotor shaft 1 of an electric motor is supported. A bearing case 8 having a receiving portion 3, a step portion 4 having a diameter larger than that of the receiving portion 3, and a tubular spring accommodating portion 7 fitted to a bearing tubular portion 6 of a housing 5 of an electric motor is provided. , A plurality of legs 9 and legs 9 housed in the spring housing portion 7 of the bearing case 8 are provided with a bearing case 8 having a tubular spring housing portion 7 fitted into the bearing tubular portion 6 of the motor housing 5. A plurality of supporting pieces 10 that are connected to each other and support the other outer periphery of the bearing 2 are provided inside the legs 9 via bent portions 11 to form a leaf spring 12.

Then, a curl bending portion 13 is provided by curling the open end of the spring accommodating portion 7 of the bearing case 8 so as to hold the end portion of the support piece 10 of the leaf spring 12.
An oil-absorbent fiber material 14 impregnated with lubricating oil, which is housed in the spring housing portion 7 and contacts a part of the outer circumference of the bearing 2, is provided, and the bent portion 11 of the leaf spring 12 is a corner portion of the step portion 4 of the bearing case 8. 15
It is provided and configured to engage with.

In the above structure, when the bearing device is assembled, it can be received by the receiving portion 3 in the bearing case 8.
The bearing 2 is put in, the leg 9 of the leaf spring 12 is housed in the spring accommodating portion 7 so that the bearing 2 is supported by the support piece 10 of the leaf spring 12, and the bent portion 11 of the leaf spring 12 is inserted into the step portion 4 of the bearing case 8. The leaf spring 12 is arranged in the bearing case 8 so as to abut the corner portion 15, and the curl bending portion 13 is formed at the open end of the bearing case 8 by curling to hold the leaf spring 12 and form a bearing device. To do.

As described above, according to the bearing device for an electric motor of the first embodiment of the present invention, the bent portion 11 of the leaf spring 12 is supported by the support piece of the leaf spring 12 with the corner 15 of the step portion 4 of the bearing case 8 as a fulcrum. Since 10 is provided, even if the curl processing is applied to the open end of the bearing case 8 to hold the leaf spring 12 and the curl bending portion 13 is formed, the leaf spring 12 can move in the axial direction. It is possible to maintain a constant centering torque, prevent variations in the centering torque, and obtain a stable low centering torque.

(Second Embodiment) As shown in FIGS. 4 and 5, the distal end portion 16 of the leg 9A of the leaf spring 12A is formed in a rounded shape which substantially matches the curl bending portion 13 of the bearing case 8. .

With the above construction, when the curl processing is performed to hold the leaf spring 12A at the open end of the bearing case 8 to form the curl bending portion 13, the leg 9A of the leaf spring 12A is formed.
16 is substantially aligned with the curl bending portion 13 of the bearing case 8, and no pressing force is applied to the tip portion 16 of the leg 9A. The spring 12A can be held.

As described above, according to the motor bearing device of the second embodiment of the present invention, when the open end of the bearing case 8 is curled, the tip of the leg 9A of the leaf spring 12A provided therein is provided. Since the leaf spring 12A is held along the curl of the open end of the bearing case 8 due to the rounded shape of the portion 16, the force at the time of curling the bearing case 8 is not applied to the leaf spring 12A, and the leaf spring 12A is constant. Since the bearing 2 is supported by the support force of, stable alignment torque can be obtained.

(Third Embodiment) As shown in FIGS. 6 and 7, the tip end portion 16A of the leg 9B of the leaf spring 12B is bent at the time of processing the curl bending portion 13 of the bearing case 8 to form a small width portion 16a.
To form

With the above construction, when the curled portion 13 is formed by curling so as to hold the leaf spring 12B at the open end of the bearing case 8, it is formed at the tip portion 16A of the leg 9B of the leaf spring 12B. The narrow width portion 16a is bent, and the curl bending portion 13 holds the leaf spring 12B.

As described above, according to the bearing device for an electric motor of the third embodiment of the present invention, the leg 9B of the leaf spring 12B disposed inside when the open end of the bearing case 8 is curled.
The small width portion 16a formed at the front end portion 16A of the blade easily bends and is inscribed in the curl bending portion 13 and supports the leaf spring 12B.
Since the leaf spring 12B is held without being applied with a large pressing force, the centering torque of the leaf spring 12B can be maintained in a stable state.

(Embodiment 4) As shown in FIGS. 8 and 9, the legs 9C of the leaf spring 12C are sequentially tapered from the bent portion 11.

With the above structure, when the curl processing is performed to hold the leaf spring 12C at the open end of the bearing case 8 to form the curl bending portion 13, the leg 9C of the leaf spring 12C is formed.
The tapered tip end portion of B is bent and the curl bending portion 13 holds the leaf spring 12C.

As described above, according to the bearing device for an electric motor of the fourth embodiment of the present invention, when the open end of the bearing case 8 is curled, the tapered tip of the leg 9C of the leaf spring 12C provided inside is formed. The portion easily bends and is inscribed in the curl bending portion 13, and the leaf spring 12C is held without a large pressing force being applied to the support piece 10 of the leaf spring 12C, so that the centering torque of the leaf spring 12C can be adjusted with a simple structure. It can be maintained in a stable state.

(Embodiment 5) As shown in FIGS. 10 and 11, a leaf spring 12 having a tapered leg 9D is provided.
The leg 9D of D is opened outward and formed arbitrarily.

With the above structure, when the leaf spring 12D is housed in the bearing case 8, the leg 9D that can be opened outward is inscribed in the inner surface of the spring housing portion 7 of the bearing case 8, and the plate is formed at the open end of the bearing case 8. When the curl processing is performed to hold the spring 12D to form the curl bending portion 13, the leg 9D is also curled and the leaf spring 12D is held.

As described above, according to the bearing device for an electric motor of the fifth embodiment of the present invention, when the open end of the bearing case 8 is curled, the leg 9 of the leaf spring 12D disposed inside is curled.
Since D is opened outward and is in close contact with the spring accommodating portion 7 due to its elasticity, it is curled when the bearing case 8 is curled and is inscribed in the curl bending portion 13, the leaf spring 12D is held, and the leaf spring 12D is held. The aligning torque of can be maintained in a stable state.

(Embodiment 6) As shown in FIG. 12 and FIG. 13, the number of legs 9E provided via bent portions 11 with respect to a plurality of supporting pieces 10A of leaf spring 12E is the same as the number of supporting pieces 10.
The same number as A is arranged on the same line, and the positional relationship is made to match.

With the above structure, the bearing 2 is accommodated in the bearing case 8.
Are supported by a plurality of supporting pieces 10A, and the supporting pieces 10A are supported by the legs 9E housed in the spring housing portion 7 in the bearing case 8 through the bent portion 11, and the force applied to the legs 9E is applied to the plurality of supporting pieces. Since it is evenly applied to 10A, a stable centering torque can be obtained.

As described above, according to the bearing device for an electric motor of the sixth embodiment of the present invention, the supporting force applied to the plurality of supporting pieces 10A is always applied uniformly, and a constant centering torque state can be maintained.

(Embodiment 7) As shown in FIGS. 14 and 15, with respect to a plurality of supporting pieces 10B of the leaf spring 12F,
The plurality of legs 9F provided via the bent portion 11 are formed by shifting their positions.

With the above structure, the bearing 2 is supported in the bearing case 8 by a plurality of supporting pieces 10B, and the supporting pieces 10B are accommodated in the spring accommodating portion 7 in the bearing case 8 via the bent portion 11. The radial force supported by the leg 9F and applied to the leg 9F is not directly applied to the support piece 10B provided at the displaced position, but is dispersed and applied to the bearing 2 when being transmitted to the support piece 10B via the bent portion 11. The pressing force of the piece 10B is small.

As described above, according to the bearing device for an electric motor of the seventh embodiment of the present invention, when the leaf spring 12F is mounted in the bearing case 8, the pressing force applied to the bearing 2 can be made small. It is possible to obtain an effective small centering torque by using the small electric motor which may be small.

(Embodiment 8) As shown in FIGS. 16 and 17, the curl bending portion 13A of the bearing case 8A is deeply formed in a substantially hemispherical shape.

With the above structure, the tip end portion of the leg 9 of the leaf spring 12 disposed in the spring accommodating portion 7 of the bearing case 8A can be provided in the curl bending portion 13A.

As described above, according to the bearing device for an electric motor of the seventh embodiment of the present invention, the tips of the legs 9 of the leaf springs 12 mounted on the bearing case 8A can be reliably provided in the curl bending portion 13A. As a result, the leaf spring 12 is reliably supported, and the centering torque for the bearing 2 is also stable.

[0035]

As is apparent from the above description of the embodiments, according to the present invention, a cylindrical shape having a receiving portion for supporting one of the outer circumferences of the bearing and having a step portion having a diameter larger than that of the receiving portion is provided. In the bearing case of, a leaf spring provided with a plurality of support pieces for supporting the other outer periphery of the bearing through a plurality of legs and bent portions is mounted,
After engaging the bent portion of the leaf spring with the corner of the stepped portion of the bearing case, the curled portion is provided at the open end of the bearing case by curling, so the pressing force of the support piece against the bearing becomes constant, It is possible to provide a bearing device for an electric motor that can obtain a stable low centering torque.

Further, by forming the tip end of the leg of the leaf spring to be rounded or bendable, a stable centering torque can be obtained without applying a large external force to the leg during the curl bending process.

Further, a small centering torque can be obtained by the number and positional relationship of the plurality of support pieces of the leaf spring and the plurality of legs.

Further, by forming the legs of the leaf springs to the outside and arbitrarily forming them, or by deeply forming the curl in the curl bending portion, the legs of the leaf springs are reliably held and the centering torque is stabilized.

[Brief description of drawings]

FIG. 1 is a sectional view showing a configuration of a bearing device for an electric motor according to a first embodiment of the present invention.

FIG. 2 is a sectional view of a leaf spring of the bearing device for an electric motor according to the first embodiment.

FIG. 3 is a sectional view of an electric motor equipped with the bearing device of the first embodiment.

FIG. 4 is a sectional view of a leaf spring of a bearing device for an electric motor according to the second embodiment.

FIG. 5 is a sectional view of a bearing device for an electric motor according to the second embodiment.

FIG. 6 is a front view of a leaf spring of a bearing device for an electric motor according to the third embodiment.

FIG. 7 is a side view showing the relationship between legs and curl bending portions of the bearing device for an electric motor according to the third embodiment.

FIG. 8 is a front view of a leaf spring of a bearing device for an electric motor according to the fourth embodiment.

FIG. 9 is a side view showing the relationship between legs and curl bending portions of the bearing device for an electric motor according to the fourth embodiment.

FIG. 10 is a sectional view of a leaf spring of a bearing device for an electric motor according to the fifth embodiment.

FIG. 11 is a sectional view of a bearing device for an electric motor according to the fifth embodiment.

FIG. 12 is a front view of a leaf spring of a bearing device for an electric motor according to the sixth embodiment.

FIG. 13 is a sectional view of a bearing device for an electric motor according to the sixth embodiment.

FIG. 14 is a schematic diagram showing the relationship between the support piece of the leaf spring and the leg of the bearing device for an electric motor according to the seventh embodiment.

FIG. 15 is a sectional view of a bearing device for an electric motor according to the seventh embodiment.

FIG. 16 is a side view showing the relationship between legs and curl bending portions of the bearing device for an electric motor according to the eighth embodiment.

FIG. 17 is a sectional view of a bearing device for an electric motor according to the eighth embodiment.

FIG. 18 is a cross-sectional view of an electric motor equipped with a conventional bearing device.

[Explanation of reference numerals] 1 rotor shaft 2 bearing 3 receiving portion 4 step portion 5 housing 7 spring accommodating portion 8, 8A bearing case 9, 9A, 9B, 9C, 9D, 9E, 9F leg 10, 10A, 10B support piece 11 Bending part 12, 12A, 12B, 12C, 12D, 12E, 12
F leaf spring 13, 13A curl bending portion 14 oil-absorbent fiber material 15 corner portion 16, 16A tip portion 16a narrow width portion

Claims (8)

[Claims] 1. A bearing made of a sintered oil-impregnated alloy in which a spherical arc surface is formed on the outer periphery for supporting the rotor shaft of an electric motor, and a receiving portion for supporting one of the outer periphery of the bearing. A bearing case having a stepped portion with a larger diameter and having a cylindrical spring storage portion to be fitted to the housing of the electric motor, a plurality of legs stored in the spring storage portion of the bearing case, and the leg connected to the leg. A leaf spring in which a plurality of supporting pieces for supporting the other of the outer circumferences of the bearings are formed inside bent legs through bent portions, and a spring of the bearing case so as to hold an end portion of the supporting piece of the leaf spring. A curl bending portion provided at the open end of the storage portion and an oil-absorbent fiber material impregnated with lubricating oil that is stored in the spring storage portion and contacts a part of the outer periphery of the bearing, and the leaf spring is bent. Of the electric motor having a structure in which the portion is engaged with the corner of the stepped portion of the bearing case. Receiving apparatus. 2. The bearing device for an electric motor according to claim 1, wherein the tip end portion of the leg of the leaf spring is formed into a rounded shape that substantially matches the curled portion of the bearing case. 3. A bearing device for an electric motor according to claim 1, wherein a tip end portion of the leg of the leaf spring is formed with a small width portion that bends when the curl bending portion of the bearing case is processed. 4. A bearing device for an electric motor according to claim 1, wherein the legs of the leaf spring are formed so as to be tapered in order. 5. A bearing device for an electric motor according to claim 1, wherein the legs of the leaf spring are formed to open outwardly. 6. The bearing device according to claim 1, wherein the plurality of supporting pieces of the leaf spring and the number of legs and the positional relationship are the same. 7. A bearing device for an electric motor according to claim 1, wherein a plurality of legs are displaced from a plurality of supporting pieces of the leaf spring. 8. The bearing device for an electric motor according to claim 1, wherein the curl bending portion of the bearing case is deeply formed in a substantially hemispherical shape.