JP3037125U - Reducer for electric motor - Google Patents

Abstract

(57) An object of the present invention is to provide a speed reducer for an electric motor, which has a structure in which a bearing of a driven shaft is reliably supported, and which can suppress an increase in cost without increasing the size of the speed reducer case. A small-diameter gear is provided at the tip of a drive shaft that is rotationally driven by an electric motor, and the small-diameter gear is housed in a reduction gear case. In the reduction gear case 5, a driven shaft 7 that supports a large-diameter gear 6 that meshes with the small-diameter gear 4 is rotatably supported by a bearing 8. The bearing support plate 11 is provided in the speed reducer case 5 on the side where the main shaft 1 projects into the speed reducer case 5.
The bearing support plate 11 and the reducer case 5
Each of the support projections 15 on the end plate 5a side is supported. The bearing 8 of the driven shaft 7 is supported by the bearing support plate 11.

Description

[Detailed description of the invention]

[0001]

[Technical field to which the invention belongs]

 The present invention relates to a reducer for an electric motor that reduces the rotational output of the electric motor.

[0002]

[Prior art]

 As a conventional speed reducer for this type of electric motor, there is one having a structure as shown in FIGS. 2 (A) and 2 (B).

This electric motor reducer has a main shaft 1 that is rotationally driven by an electric motor (not shown). The main shaft 1 is rotatably supported in a cylindrical portion 2 by a bearing 3, and the tip of the main shaft 1 is rotatably supported. The small-diameter gear 4 provided in the housing is housed in the reduction gear case 5, and in the reduction gear case 5, a driven shaft 7 that supports a large-diameter gear 6 that meshes with the small-diameter gear 4 is rotatably supported by a bearing 8. It is structured. In this case, the bearing 8 is partly fitted and supported by an arc-shaped bearing support portion 9 ′ protruding from the end plate portion 5 a of the reduction gear case 5. A tubular case body 5b is integrally formed with the end plate portion 5a.

In such a speed reducer for an electric motor, the distance between the main driving shaft 1 and the driven shaft 7 is small, and when viewed from the end side of the reduction gear case 5 as shown in FIG. There is a problem that an overlapping portion 10 between the bearing 3 and the bearing 8 is generated, the bearing supporting portion 9'is not annular, and the bearing 8 cannot be sufficiently supported.

In order to avoid this, a speed reducer for an electric motor having a structure as shown in FIGS. 3 (A) and 3 (B) or FIGS. 4 (A) and 4 (B) has been proposed.

In the motor reducer shown in FIGS. 3A and 3B, the end plate portion 5a of the speed reducer case 5 and the cylindrical case body portion 5b are formed separately, and the end plate portion 5a is formed. The bearing support plate 11 is fitted in the cylindrical case body 5b on the side adjacent to the drive shaft through hole 12 and the driven shaft 7 through which the drive shaft 1 is rotatably pierced. A mounting hole 13 for mounting the bearing 8 is provided. The bearing 8 is fitted into the mounting hole 13 of the bearing support plate 11 via the bearing holder 14. A cylindrical case body 5b having such a bearing support plate 11 is fixed to the end plate 5a. Other configurations are the same as those in FIGS. 2A and 2B.

In the electric motor reducer shown in FIGS. 4A and 4B, the distance between the driving shaft 1 and the driven shaft 7 is widened, and the annular bearing support portion 9 has the end plate portion 5 a of the reduction gear case 5. Is fully supported by. Other configurations are the same as those in FIGS. 2A and 2B.

[0008]

[Problems to be solved by the device]

 However, in the electric motor reducer having the structure shown in FIGS. 3A and 3B, since the end plate portion 5a of the reduction gear case 5 and the cylindrical case body portion 5b are formed separately, There has been a problem that the cost of the mold forming the speed reducer case 5 is increased. In addition, in such a structure, parts cannot be supplied from the same direction, which makes it difficult to automate assembly.

On the other hand, in the electric motor reducer having the structure shown in FIGS. 4A and 4B, the outer diameter of the reducer case 5 is large because the distance between the main driving shaft 1 and the driven shaft 7 is widened. Therefore, there was a problem that the speed reducer became larger. In addition, there is a problem in that the size of the reduction gear case 5 is increased, resulting in cost increase.

An object of the present invention is to provide a speed reducer for an electric motor, which has a structure for reliably supporting a bearing of a driven shaft, and which can suppress an increase in cost without increasing the size of the speed reducer case. .

Another object of the present invention is to provide a speed reducer for an electric motor having a structure that enables automation of assembly.

[0012]

According to the present invention, a small-diameter gear provided at the tip of a main shaft that is rotationally driven by an electric motor is housed in a reduction gear case, and a large-diameter gear that meshes with the small diameter gear is provided in the reduction gear case. This is an improvement on a reduction gear for an electric motor in which a driven shaft supporting a radial gear is rotatably supported by a bearing.

In the reducer for an electric motor according to the present invention, a bearing support plate is disposed in the reducer case on the side where the main shaft projects into the reducer case, and the end plate portion side of the reducer case is disposed. The bearing of the driven shaft is supported by the bearing support plate.

When the bearing of the driven shaft of the bearing support plate is supported in this manner, the bearing support plate is a separate component from the end plate portion of the reduction gear case, so the distance between the main drive shaft and the driven shaft is reduced. The bearing of the driven shaft can be reliably supported by the bearing support plate even if the width is narrow. Moreover, since the distance between the main shaft and the driven shaft can be narrowed, it is possible to suppress an increase in cost without increasing the size of the reduction gear case. Particularly, since the bearing support plate is supported on the end plate side of the reduction gear case on the side where the main shaft projects into the reduction gear case, the reduction gear case and the tubular case are Since it is not necessary to form it separately from the main body, it is possible to avoid an increase in the cost of the mold forming the reducer case.

In this case, the bearing support plate is formed along the inner circumference of the reduction gear case, and is fixed to the end plate portion side of the reduction gear case with a screw, and the main shaft is rotatably attached to the bearing support plate. By providing a hole to be penetrated through and a mounting hole for mounting the bearing of the driven shaft, parts can be supplied from the same direction, and the assembly can be automated.

Further, when a plurality of supporting protrusions for supporting the bearing support plate are provided on the inner surface of the end plate portion of the reduction gear case, the bearing support plate is kept floating from the inner surface of the end plate portion of the reduction gear case. It can be surely supported.

[0017]

[Embodiment of the invention]

 1A and 1B show an example of an embodiment of a speed reducer for an electric motor according to the present invention.

In the reducer for an electric motor of this example, a bearing support plate 11 is arranged in the reducer case 5 on the side where the main shaft 1 projects into the reducer case 5, and the reducer case 11 Is supported on the end plate portion 5a side. That is, on the inner surface of the end plate portion 5a of the speed reducer case 5, a plurality of support protrusions 15 for supporting the bearing support plate 11 are provided at 120 ° intervals, and the positioning step portions 15a of these support protrusions 15 are provided with bearing support plate portions. 11 is positioned, and the bearing support plate 11 is fixed to each support protrusion 15 with a screw 16 as a fixing means. The bearing support plate 11 is provided with a main shaft through hole 12 that rotatably penetrates the main shaft 1 and a mounting hole 13 for mounting the bearing 8 of the driven shaft 7. The bearing 8 is fitted into the mounting hole 13 of the bearing support plate 11 by press fitting or the like. Other configurations are the same as those in FIGS. 2A and 2B.

As described above, in this example, since the bearing 8 of the driven shaft 7 is supported by the bearing support plate 11, the bearing support plate 11 is a separate component from the end plate portion 5 a of the reduction gear case 5. Even if the distance between the main driving shaft 1 and the driven shaft 7 is small, the bearing 8 of the driven shaft 7 can be reliably supported by the bearing support plate 11 as shown in the figure. Also in this example, since the distance between the main shaft 1 and the driven shaft 7 can be narrowed, it is possible to suppress an increase in cost without increasing the size of the reduction gear case 5. Particularly, since the bearing support plate 11 is supported on the end plate portion 5a side of the reduction gear case 5 on the side where the main shaft 1 projects into the reduction gear case 5, the reduction gear case 5 is attached to the end plate portion. It is not necessary to separately form 5a and the cylindrical case body portion 5b, and it is possible to avoid the cost of the mold forming the reduction gear case 5.

Further, in this example, the bearing support plate 11 is formed along the inner circumference of the speed reducer case 5, and is fixed to the inner surface of the end plate portion 5a of the speed reducer case 5 with screws 16 and Since the bearing support plate 11 is provided with a driving shaft through hole 12 for rotatably penetrating the driving shaft 1 and a mounting hole 13 for mounting the bearing 8 of the driven shaft 7, parts can be supplied from the same direction, and assembling is possible. Can be automated.

In this case, when the bearing 8 is a rolling bearing, the rolling bearing is integrated with the driven shaft 7 and then assembled to the bearing support plate 11, and in this state, the bearing support plate 11 is attached to the support protrusion 15. Secure with screws 16.

On the other hand, when the bearing 8 is a slide bearing made of an oil-impregnated alloy material, the slide bearing is previously assembled to the bearing support plate 11 and the bearing support plate 11 is fixed to the support protrusion 15 with the screw 16. After that, the driven shaft 7 is inserted into the slide bearing.

Further, in this example, since the plurality of support protrusions 15 that support the bearing support plate 11 are provided on the inner surface of the end plate portion 5a of the speed reducer case 5, the bearing support plate 11 is mounted on the speed reducer. It can be reliably supported in a state of being floated from the inner surface of the end plate portion 5a of the case 5.

Further, in the example shown in FIG. 1, the bearing 8 is directly attached to the hole 13 of the bearing support plate 11, but the bearing 8 is mounted via the bearing holder 14 as in the case of FIG. It can also be mounted in the mounting hole 13 of 11.

[0025]

[Effect of the invention]

 In the reducer for an electric motor according to the present invention, since the bearing of the driven shaft of the bearing support plate is supported, the bearing support plate is a separate part from the end plate portion of the reducer case, so Even if the distance from the shaft is small, the bearing of the driven shaft can be reliably supported by the bearing support plate. Moreover, since the distance between the main shaft and the driven shaft can be narrowed, it is possible to suppress an increase in cost without increasing the size of the reduction gear case. In particular, the bearing support plate is supported by the end plate portion side of the reduction gear case on the side where the main drive shaft projects into the reduction gear case, so that the reduction gear case is cylindrical with the end plate portion as in the conventional case. It is not necessary to separately form the case main body portion, and it is possible to avoid an increase in the cost of the mold forming the reduction gear case.

[Brief description of the drawings]

FIG. 1A is a longitudinal sectional view of an essential part showing an example of an embodiment of an electric motor speed reducer according to the present invention, and FIG. 1B is a line I-I in a state in which each axis is omitted in FIG. 1A. FIG.

FIG. 2A is a vertical cross-sectional view of a main part of a conventional speed reducer for a motor in which a distance between a main driving shaft and a driven shaft is narrowed;
FIG. 2A is a sectional view taken along line II-II in FIG.

3A is a vertical cross-sectional view of a main part of an example of a conventional electric motor reducer that is an improvement of FIG. 2, and FIG. 3B is a cross-sectional view taken along line III-III of FIG. is there.

FIG. 4A is a vertical cross-sectional view of a main part of another example of a conventional electric motor speed reducer improved from FIG. 2, and FIG. 4B is a cross-sectional view taken along line IV-IV in FIG. It is a figure.

[Explanation of symbols]

 1 Main shaft 2 Cylindrical part 3 Bearing 4 Small diameter gear 5 Reduction gear case 5a End plate part 5b Case body part 6 Large diameter gear 7 Driven shaft 8 Bearing 9'Arc-shaped bearing support part 9 Annular bearing support part 10 Overlapping part 11 Bearing support plate 12 Main shaft through hole 13 Mounting hole 14 Bearing holder 15 Support protrusion 15a Positioning step 16 Screw (fixing means)

Claims (3)

[Utility model registration claims] 1. A small-diameter gear provided at the tip of a main shaft that is rotationally driven by an electric motor is housed in a reduction gear case,
In a reducer for an electric motor, in which a driven shaft supporting a large-diameter gear meshing with the small-diameter gear is rotatably supported by a bearing in the reduction gear case, the main driving shaft protruding into the reduction gear case. Side, a bearing support plate is disposed in the speed reducer case and is supported on the end plate side of the speed reducer case, and the bearing of the driven shaft is supported by the bearing support plate. Decelerator. 2. The bearing support plate has a shape along an inner circumference of the speed reducer case and is fixed to the end plate portion side of the speed reducer case with a screw, and the bearing support plate has the shape The reduction gear for an electric motor according to claim 1, wherein a hole through which the main shaft is rotatably pierced and a mounting hole for mounting the bearing of the driven shaft are provided. 3. The reduction gear for an electric motor according to claim 1, wherein a plurality of support protrusions that support the bearing support plate are provided on an inner surface of the end plate portion of the reduction gear case. Machine.