JPH0353585Y2 - - Google Patents

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to a small electric motor having an improved mounting structure of an end bracket to a housing containing a stator and a rotor.

[Prior Art] Conventionally, small electric motors have been used in air conditioners for automobiles to drive blowers. This electric motor consists of a stator, a rotor, and a rotating shaft that supports the rotor, all arranged in a cylindrical housing, with a bearing for the rotating shaft located in the center of the opening of the housing. A complete end bracket is installed. In this case, a plurality of mounting grooves oriented in the thickness direction are formed at the open end of the housing, and protrusions located in the mounting grooves are provided at the outer peripheral edge of the end bracket. In this state, both side walls of the mounting groove are caulked with a pressure force of, for example, 1.5 using a tool so that the width thereof becomes narrow, thereby holding the protrusion in a state where it cannot be removed.

[Problems to be solved by the invention] However, when deforming the mounting groove of the housing by caulking, there are cases where the deforming force slightly protrudes toward the center from the thickness direction area of the housing and comes into pressure contact with the outer peripheral edge of the end bracket. be. In this case, the end bracket is displaced by the pressing force, causing misalignment, and the rotating shaft and rotor are no longer concentric with the stator, resulting in unsmooth rotation. There are some inconveniences that may hinder the longevity of the product.

The present invention was developed in view of the above circumstances, and its purpose is to prevent the end bracket from shifting its position and to ensure that the end bracket remains fixed even though the end bracket is attached to the housing by deforming the mounting groove. To provide a small electric motor that maintains concentricity of a rotor with respect to a child, maintains an initial good and smooth rotational state over a long period of time, and contributes to a longer life.

[Means for Solving the Problems] The present invention includes a cylindrical housing in which a stator and a rotor are provided inside and an end bracket concentrically mounted in an opening, and a cylindrical housing in which a stator and a rotor are provided inside and an end bracket is installed concentrically in an opening. a mounting groove formed in the thickness direction of the end bracket, and a protrusion formed on the outer circumferential edge of the end bracket and positioned within the mounting groove, the mounting groove having a narrow width on both side walls of the mounting groove. In the device that prevents the protrusion from coming out by deforming,
A relief portion for a portion of the deformed portion of the mounting groove that protrudes toward the center of the housing is provided in the housing or the end bracket.

[Function] According to the present invention configured as described above, when the mounting groove is deformed, the portion of the deformed portion that protrudes toward the center of the housing is accommodated by the relief portion, and the end bracket is not misaligned with the rotating shaft. A concentric state with the stator is maintained.

[Embodiment] A first embodiment of the present invention will be described below with reference to FIGS. 1 to 5. In the case of an air conditioner for an automobile, a small electric motor 1 for driving a blower (not shown) is provided. As shown in FIG. 1, this electric motor 1 includes a housing 3 having a stator 2 made of a permanent magnet attached therein. This housing 3 is formed into a cylindrical shape from a steel plate approximately 2.9 mm thick, and a first end bracket 5 having a bearing 4 in the center is attached to the left side of the opening, and a second end bracket 5 is attached to the right end of the opening. 4 mounting grooves 6 as shown in the figure
is formed completely in the thickness direction. As seen in FIG. 2, the second end bracket 7 has a generally rectangular plate shape and is located within the opening at the right end of the housing 3. This bracket 7 has a bearing 9 attached to its center, while an arcuate flange 10 is formed on its short side, leaving a small gap with the inner peripheral surface of the housing 3, as shown in FIG. The flange 10 has a protrusion 11 located in the mounting groove 6 integrally extending outward, and has notches 12 opened to the left and right side walls 6a and 6b of the mounting groove 6 as escape parts. is forming. In this state, the outer periphery of the housing 3 is tightened with a jig to prevent the housing 3 from expanding outward.The left and right side walls 6a, 6b of the mounting groove 6 in the housing 3 have a pair of sharp edges as shown in FIG. The tool 13 having the teeth 13a, 13a receives a pressing force of approximately 1.5〓, deforms the mounting groove 6 so that it becomes narrower, and the protrusion 1
1 is caulked to prevent it from coming off as shown in FIGS. 3 to 5. The rotating shaft 14 is arranged concentrically within the housing 3, one end is supported by the bearing 4, and the first end is supported by the bearing 4.
A centrifugal fan (not shown) is fitted into the portion projecting outward from the end bracket 5, and the other end is supported by a bearing 9 of the second end bracket 7. The rotating shaft 14 has a rotor 15 located concentrically with the stator 2, and a first end bracket 5.
A commutator 16 is provided in close proximity to the commutator 16 . Although not shown in the drawings, the commutator 16 has a pair of brushes urged by a spring so as to come into elastic contact with the commutator 16. Terminals 17 and 18 for a power outlet are connected to the brush via lead wires (not shown).

Now, according to the above structure, since the notch part 12 is formed in the second end bracket 7 so as to oppose the left and right side wall parts 6a and 6b of the mounting groove 6, that is, the deformed part, when the second end bracket 7 is installed, ,
The portions of the left and right side walls 6a, 6b of the mounting groove 6 that deform toward the center of the housing 3 are accommodated in the notch 12 as shown in FIG. Therefore, the second end bracket 7 is not subjected to any pressing force from the deformed portions of the side walls 6a and 6b, and is prevented from being displaced, thereby improving the concentricity of the rotor 15 and the rotating shaft 14 with respect to the stator 2. is ensured,
The initial good and smooth rotational state can be maintained over a long period of time, contributing to longer life. In the case of this first embodiment, the mounting groove 6 and the protrusion 11 may be tapered as shown in FIG. 2a.

Next, a second embodiment of the present invention will be described with reference to FIGS. 6 and 7, in which the same parts as those in the first embodiment are denoted by the same reference numerals. Only the different parts will be described below. In this second embodiment, the notch 12 of the second end bracket 7
Instead, a notch 19 is provided in the housing 3. This notch 19 is formed by cutting out a portion of the inner diameter side of the housing 3 at positions that match the left and right side walls 6a and 6b of the mounting groove 6, respectively. is forming. With this structure, the portions of the side walls 6a and 6b deformed by caulking that are directed inward of the housing 3 are accommodated in the notch 19, so that the same effect as in the first embodiment can be obtained. In this case, assuming that the housing is attached to the annular flange by fitting, a notch may be formed on the outer diameter side of the housing so that the housing and the flange do not become non-concentric.

In addition, instead of the notch in the first embodiment, a gutter-like bulge that is recessed inward is provided, for example, by press molding.
The deformed portion from the mounting groove may be accommodated within this bulged portion. In addition, various changes can be made to the specific implementation without departing from the gist of the bill.

[Effects of the invention] As described above, according to the invention, even though the end bracket is mounted to the housing by deforming the mounting groove, the end bracket does not shift in position and remains fixed. The concentricity of the rotor with respect to the child is maintained, the initial good and smooth rotational state is maintained over a long period of time, and this has excellent practical effects such as contributing to a longer life.

[Brief explanation of the drawing]

1 to 5 show a first embodiment of the present invention, in which FIG. 1 is an overall vertical sectional view, FIG. 2 is an exploded perspective view of an end bracket and a housing, and FIG.
2 is a cutaway front view showing the main parts of the first embodiment with some changes, FIG. 3 is a perspective view of the entire assembly showing the installation state, and FIG. 4 is an explanation showing how to install the end bracket using a tool. Fig. 5 is a partial front view showing the installed state, Fig. 6 and Fig. 7 show a second embodiment of the present invention, Fig. 6 is a view corresponding to Fig. 2, and Fig. 7 is a view corresponding to Fig. It is a figure equivalent figure. In the figure, 2... Stator, 3... Housing, 6...
...Mounting groove, 7...Second end bracket (end bracket), 11...Protrusion, 12, 19...Notch (relief part), 15...Rotor.

Claims (1)

[Claims for Utility Model Registration] 1. A cylindrical housing in which a stator and a rotor are provided and an end bracket is concentrically attached within the opening, and a housing formed in the thickness direction at the opening end of the housing. a mounting groove formed on the outer peripheral edge of the end bracket and a protrusion positioned in the mounting groove; A small electric motor that prevents a protrusion from coming off, characterized in that the housing or the end bracket is provided with a relief portion for a portion of the deformed portion of the mounting groove that protrudes toward the center of the housing. 2. The small electric motor according to claim 1, wherein the escape portion is a notch formed in the end bracket to correspond to the deformed portion of the mounting groove. 3. The relief portion is formed by cutting out a portion of the inner diameter side of the housing, which is provided at the open end of the housing to match the deformed portion of the mounting groove. The small electric motor described in item 1.