JPH0543762U - Small motor - Google Patents

Abstract

(57) [Abstract] [Purpose] The end cover rotatably supports the end of the armature shaft, thereby reducing the number of bearings that rotatably support the armature shaft, which is advantageous in terms of cost. A shaft support portion 3a3 for rotatably supporting an armature shaft 5 of an armature 4 is provided on an end cover 3 assembled to a motor yoke 2, and a lubricating oil 2 is formed on the outer circumference of the shaft support portion 3a3 in an annular shape.
An oil reservoir groove 3a5 for storing 0 was formed.

Description

[Detailed description of the device]

[0001]

[Industrial applications]

 The present invention relates to a small motor for an actuator used as a drive source of an actuator that automatically locks and unlocks an automobile door, for example.

[0002]

[Prior Art]

 3 and 4 exemplify a small motor used as a drive source for an actuator that automatically locks and unlocks a door of an automobile. The small motor 50 shown in the drawing is an armature 51. An armature shaft 52 is provided at the center, and a coil 54 is provided around an iron core 53 fixed to the center of the armature shaft 52.

A commutator 55 is provided near the base end, which is the lower side of the armature shaft 52 in FIG. 3, and a part of the coil 54 is connected to the commutator 55.

The armature 51 is housed inside a substantially disk-shaped end cover 57 that is assembled to the motor yoke 56 and has a substantially cylindrical shape with one end closed.

A bearing mounting portion 56a having a concave shape on the motor yoke 56 side is provided on the upper side of the motor yoke 56 in FIG. 3, and the bearing mounting portion 56a is provided with an oil-impregnated body separate from the motor yoke 56. A bearing 58 made of metal is mounted in a state of being aligned with a shaft hole 56b formed in the center of the upper end side of the motor yoke 56.

An upper end of the armature shaft 52 in the drawing is inserted through the bearing 58, and the output mechanism in the actuator, which is a load, is applied to the tip of the armature shaft 52 protruding from the motor yoke 56. Are designed to be connected.

A magnet 59 is fixed to the inside of the motor yoke 56, and an opening 56c of the motor yoke 56 on the lower side in FIG. 3 is fixed by caulking to the outer peripheral side of the end cover 57. I am doing it.

On the upper side in FIG. 3 of the end cover 57, elastic brush holders 60, 60 are attached at positions corresponding to the commutator 55, and are attached to the brush holders 60, 60, respectively. The brushes 61, 61 are in pressure contact with the commutator 55.

Further, a bearing mounting portion 57 a on the end cover 57 side is provided in the center of the end cover 57, and a bearing 62, which is a separate oil-impregnated metal from the end cover 57, is provided in this bearing mounting portion 57 a. It is installed.

As shown in FIG. 4, the bearing mounting portion 57 a projects in a rectangular shape toward the upper side of the end cover 57 in the drawing, and has an outer diameter dimension above the central portion of the outer circumference of the bearing 62. A protrusion 57a2 having a crimping surface 57a1 having an inner diameter slightly smaller than that of the end cover 57 is provided on the lower side of the outer periphery of the bearing 62. A recess 57a4 is provided that defines a support surface 57a3 having an inner diameter dimension that substantially matches the diameter dimension.

Then, the bearing 62 is pushed toward the recess 57a4 from the protrusion 57a2 side of the bearing mounting portion 57a, so that the lower portion of the outer periphery of the bearing 62 is in contact with and supported by the support surface 57a3. The central portion and the upper portion of the outer periphery of 62 are fitted by the protrusion 57a 2, and the bearing 62 is attached to the end cover 57.

Here, the upper side in FIG. 3 of the armature shaft 52 is rotatably supported by the bearing 58 mounted on the bearing mounting portion 56 a of the motor yoke 56, and mounted on the bearing mounting portion 57 a of the end cover 57. The lower side of the armature shaft 52 in FIG. 3 is rotatably supported by the bearing 62.

Further, external connection terminals 63 and 64 are provided below the end cover 57 so as to project downward in FIG. 3, and the external connection terminals 63 and 64 are provided with the external connection terminals 63 and 64, respectively. Brush holders 60, 60 are connected.

In the small motor 50 having such a structure, the coil 54 is provided by supplying a predetermined power to the commutator 55 from the external connection terminals 63 and 64 via the brush holders 60 and 60 and the brushes 61 and 61. When is excited, the armature 51 is rotated by electromagnetic induction between the coil 54 and the magnet 59, so that the armature shaft 52 rotates and the rotation of the armature shaft 52 causes the output mechanism to output.

However, in the conventional small-sized motor 50 described above, the end cover 57 is provided with the bearing mounting portion 57 a on the end cover 57 side for mounting the bearing 62, and the motor yoke 56 is mounted with the bearing 58. A bearing mounting portion 56a on the motor yoke 56 side is provided, and a bearing mounting portion 57a on the end cover 57 side and a bearing mounting portion 56a on the motor yoke 56 side are separate bearings for the end cover 57 and the motor yoke 56, respectively. Since the structure is such that both ends of the armature shaft 52 are rotatably supported by mounting 62 and 58, the number of parts is increased by the bearings 62 and 58 which are separate from the end cover 57 and the motor yoke 56, respectively. At the same time, the number of man-hours required to form the bearings 62 and 58, which are separate from the end cover 57 and the motor yoke 56, respectively, and The man-hours for mounting the bearings 62 and 58 must be taken into consideration in assembling the motor as a whole, which has a drawback that the man-hours required for assembling are increased.

[0016]

[Problems to be solved by the device]

 The problem to be solved is that if the bearing is separate from the end cover and the motor yoke, the number of parts will increase, and the number of man-hours to be created separately and the man-hours required for assembly will increase, which is a cost disadvantage. is there.

[0017]

[Means for Solving the Problems]

 In order to eliminate the man-hours required for separately manufacturing the bearing and the man-hours required for assembling the bearing, the present invention provides the end cover with the shaft support portion that rotatably supports the armature shaft, and also has an annular shape on the outer circumference of the shaft support portion. The most important feature is the formation of an oil storage groove for storing lubricating oil, which is advantageous in terms of cost by eliminating the need for one of the bearings that rotatably support the armature shaft. The purpose was to achieve by making a small change in the mold when creating the end cover.

[0018]

[Action]

 In the small motor according to the present invention, the armature shaft is rotatably supported by the shaft support while the lubricating oil is held on the outer periphery of the shaft support by the oil reservoir groove formed in the shaft support provided on the end cover. This eliminates the need to create a bearing separate from the end cover, and eliminates the need to mount the bearing on the end cover.

[0019]

【Example】

 An embodiment of a small motor according to the present invention will be described below with reference to FIGS.

In the illustrated small motor 1, an armature 4 is housed inside a motor yoke 2 and an end cover 3 attached to the motor yoke 2.

An armature shaft 5 is provided at the center of the armature 4, and a coil portion 7 in which a copper wire is wound around an iron core 6 fixed to the central portion of the armature shaft 5 is arranged.

A rectifier 8 is provided near the base end, which is the lower side of the armature shaft 5 in FIG. 1, and a part of the coil portion 7 is connected to the commutator 8. ..

A bearing support 2a1 having a round hole is provided at the center of the upper wall 2a of the motor yoke 2 on the upper side in FIG. 1, and the bearing support 2a1 is provided with a bearing support 2a1. A bearing 9 which is an oil-impregnated metal is mounted from the inside.

A magnet mounting surface 2b having a cylindrical shape is formed inside the motor yoke 2 on the lower side of the ceiling wall 2a in FIG. 1, and the magnet mounting surface 2b has a ring shape. The magnet 10 is fixed.

Further, inside the motor yoke 2, the lower side of the magnet mounting surface 2 b is a mounting end portion 2 c to the end cover 3, and the mounting end portion 2 c is crimped to the end cover 3. It is like this.

On the other hand, as is clear from FIG. 1, the end cover 3 has a U-shaped cross section and is integrally molded of resin, and has a disk-shaped outer periphery of the end cover body 3 a. An insertion end 3b1 is formed near the upper end of the peripheral wall 3b, which has a circular shape on the side and protrudes upward in FIG. 1, for insertion inside the mounting end 2c of the motor yoke 2.

Further, on the upper surface 3a1 of the end cover body 3a of the end cover 3 which is the upper side in FIG. 1, there are provided brush holders 11 and 11 having elasticity and projecting upward in the figure, the commutator 8 The brushes 12, 12 attached to the brush holders 11, 11 are in pressure contact with the commutator 8.

At the center of the end cover body 3a of the end cover 3, there is provided a shaft support portion 3a3 which communicates in a circular hole shape from the upper surface 3a1 to the lower surface 3a2 which is the lower side in FIG. There is.

As is apparent from FIG. 2, the shaft support portion 3a3 includes one side shaft contact protrusion 3a4, an oil reservoir groove 3a5, and the other side shaft contact protrusion 3a6 from the upper surface 3a1 to the lower surface 3a3. Are provided in order.

Further, the one-side shaft abutting protrusion 3a4 and the other-side shaft abutting protrusion 3a6 are curved inward toward the inner peripheral side of the shaft supporting portion 3a3 and project annularly. The inner diameter of the contact projections 3a4, 3a6 is slightly larger than the outer diameter of the armature shaft 5 near the lower end in FIG.

The oil reservoir groove 3a5 is located at the center of the shaft abutting protrusions 3a4, 3a6 and has an inner diameter larger than the inner diameter of the shaft abutting protrusions 3a4, 3a6. It is formed as a concave shape in an annular shape that is curved toward, and a lubricant 20 such as grease is enclosed in a gap between the oil reservoir groove 3a5 and the armature shaft 5.

Here, the armature shaft 5 of the armature 4 can be rotated by the bearing 9 by inserting the front end side, which is the upper side in FIG. 1, into the bearing 9 mounted on the bearing support portion 2 a 1 of the motor yoke 2. The armature shaft 5 is rotatably supported by the shaft supporting portion 3a3 by inserting the base end side, which is the lower side in FIG. 1, into the shaft supporting portion 3a3 of the end cover 3.

Further, the lower side of the armature shaft 5 in FIG. 1 projects downward from the shaft support portion 3a3, and the output mechanism in the actuator is connected to this projecting portion.

Further, external connection terminals 13 and 14 are arranged near the outer periphery of the end cover body 3a, and the brush holders 11 and 11 are connected to the external connection terminals 13 and 14, respectively. ..

In the small-sized motor 1 having such a structure, a coil is provided by supplying a predetermined power source to the commutator 8 from the external connection terminals 13 and 14 via the brush holders 11 and 11 and the brushes 12 and 12. When the portion 7 is excited, the armature 4 is rotated by electromagnetic induction between the coil portion 7 and the magnet 10, so that the armature shaft 5 is rotated and the output mechanism is operated to output.

During this time, when the armature 4 rotates, the tip end side of the armature shaft 5 is rotatably supported by the bearing 9 mounted on the bearing support portion 2 a 1 of the motor yoke 2, and the base end side of the armature shaft 5 is the end cover 3 of the end cover 3. The shaft support portion 3a3 is rotatably supported by the lubricant 20 enclosed in the oil reservoir groove 3a5 in a lubricated state.

[0037]

[Effect of the device]

 As described above, since the small motor according to the present invention has the above-mentioned configuration, the oil reservoir groove formed in the shaft support portion provided in the end cover allows the lubricating oil to be provided on the outer periphery of the shaft support portion. Since the armature shaft is rotatably supported by the shaft support in the state where the bearing is stored, it is less necessary to create a bearing separate from the end cover, and it is not necessary to mount the bearing on the end cover. It has an excellent effect in terms of cost.

[Brief description of drawings]

FIG. 1 is a partially cutaway side view of an embodiment of a small motor according to the present invention.

FIG. 2 is an external perspective view of an end cover portion in the small motor shown in FIG.

FIG. 3 is a partially cutaway side view of a conventional small motor.

4 is an external perspective view of an end cover portion in the small motor shown in FIG.

[Explanation of symbols]

 1 Small Motor 2 Motor Yoke 3 End Cover 3a3 Shaft Support 3a5 Oil Storage Groove 4 Armature 5 Armature Shaft 10 Magnet 20 Lubricating Oil

Claims (1)

[Scope of utility model registration request] 1. A magnet, an armature, a motor yoke for supporting one end of an armature shaft provided on the armature, and an end cover assembled to an opening end of the motor yoke, the end cover being provided with an armature shaft. A small motor characterized in that a shaft support portion that rotatably supports the other end is provided, and an oil reservoir groove that is annular in the outer periphery of the armature shaft and that stores lubricating oil is formed in the shaft support portion.