JP2002044909A - Geared motor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a geared motor, in which engagement precision of gear is secured by ensuring rigidity of a housing without adding weight, and generation of abnormal noise can be prevented, and durability is improved. SOLUTION: In the geared motor 10, a worm 20, a worm wheel 24, and an output shaft 36 are accommodated in a motor housing 18 of a gear part 10B. In the motor housing 18, a cover plate 48, configured to have high rigidity by providing a rib 48D, is disposed in abutting against a cover retention face 18C. Thereby, the motor housing 18 and the cover plate 48 are integrated to form a closed cross section, and the rigidity of the motor housing 18 is greatly enhanced. Furthermore, there is neither increment in parts, nor weight increase.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a geared motor, and more particularly, to a geared motor applied to a power window device for opening and closing a window glass of a vehicle door.

[0002]

2. Description of the Related Art For example, a geared motor is used as a driving source in a power window device for opening and closing a window glass of a vehicle and a sunroof device for opening and closing a sunroof. In such a geared motor, a worm connected to a motor rotating shaft in a housing connected to a motor unit meshes with a worm wheel to reduce the rotation of the motor rotating shaft, and the reduced rotation is used as a power window. There is a configuration in which power is transmitted to an output shaft connected to a device or the like. In such a geared motor, the size and weight are reduced, and the power window device and the sunroof device can be reliably operated in a vehicle door or a roof where space is limited.

Incidentally, the housing of the above-described geared motor has a large opening for accommodating a worm wheel therein when the housing is formed of a thermoplastic resin for weight reduction. After the worm wheel and other parts are assembled, the opening is covered with a cover member made of a thermoplastic resin, similarly to the housing.

However, in the conventional geared motor as described above, since the housing has a large opening, when used under a high load, a reaction force from a bearing portion of the output shaft or a mounting portion to the vehicle is applied to the housing. When acting, the housing will be deformed or distorted. For this reason, there has been a problem that the meshing accuracy of the gear portion is not maintained, and abnormal noise is generated and durability is deteriorated. Further, in the conventional geared motor as described above, the cover member is connected to the opening end face of the housing via a sealing material or an adhesive in order to prevent water or foreign matter from entering the inside of the housing. The member is not configured to ensure the rigidity of the housing as a strength member.

[0005] On the other hand, the demands on the geared motor from the vehicle side are further reduction in weight and increase in the use environment, and the above-mentioned problems become more conspicuous with these demands. In other words, if the reinforcement material such as ribs provided on the outer surface of the housing is reduced due to the demand for weight reduction, the rigidity of the housing is reduced, and the housing is more likely to be deformed or distorted. Underneath, there has been a problem that the elastic modulus of the material itself is reduced, and the deformation and distortion of the housing are more likely to occur.

SUMMARY OF THE INVENTION In consideration of the above fact, the present invention secures the rigidity of the housing without increasing the weight, thereby ensuring gear engagement accuracy, preventing generation of abnormal noise, and improving durability. The purpose is to get a motor.

[0007]

In order to achieve the above object, a geared motor according to the first aspect of the present invention is formed in a bottomed cylindrical shape, and has a worm connected to a motor rotating shaft and a worm meshed with the worm. A housing that fits and houses a worm wheel that drives the output shaft, and is formed in a disk shape corresponding to the opening of the housing, and is formed in a disk shape corresponding to the opening of the housing. The outer peripheral portion has a fitting portion that is fitted over substantially the entire circumference on one or both of a radially inward circumferential surface and a radially outward circumferential surface near the opening of the housing,
A cover member that covers the opening of the housing by being fitted to the housing at the fitting portion and that supports the opening of the housing in a radial direction thereof.

In the geared motor according to the first aspect, when the motor is started and the motor rotating shaft is rotated, the worm wheel meshing with the worm connected to the motor rotating shaft is rotated, and the rotation of the motor rotating shaft is reduced. Is done. The rotation of the worm wheel is transmitted to, for example, an output shaft connected to a power window device, and the power window device is driven.

In this geared motor, the cover member has one of a radially inward circumferential surface and a radially outward circumferential surface near the opening of the housing at the fitting portion formed on the outer peripheral portion thereof. Alternatively, the housing and the cover member are fitted together over substantially the entire circumference (fitted to the housing) to cover the opening of the housing and support the opening of the housing in the radial direction. To form a closed section. For this reason, the rigidity of the housing is greatly improved, and the deformation and distortion of the housing due to the reaction force from the bearing portion of the output shaft and the mounting portion to the vehicle are suppressed, and the accuracy of gear engagement is maintained.

Further, since a cover member for covering the opening of the housing to prevent water or the like from entering the housing is used as a strength member, the number of parts is not increased and the weight is not increased.

The radially inward circumferential surface of the housing and the radially outward circumferential surface of the housing as defined in claim 1 are the same as the inner circumferential surface and outer circumferential surface of the housing cylindrical portion, as well as the housing cylindrical shape. It includes both wall surfaces of the groove when the groove is formed at the opening end of the portion.

The fitting of the cover member to the housing is preferably performed by, for example, press fitting or heat caulking.

As described above, in the geared motor according to the first aspect, by ensuring the rigidity of the housing without increasing the weight, the meshing accuracy of the gears is ensured, the generation of abnormal noise can be prevented, and the durability is improved. I do.

A geared motor according to a second aspect of the present invention is the geared motor according to the first aspect, wherein the cover member has an annular rib formed along an outer peripheral surface thereof, and the rib is fitted. And the rib is in contact with the inner peripheral surface of the housing at the outer peripheral surface of the rib.

In the geared motor according to the second aspect, since the rib is formed along the circumferential surface of the cover member, the rigidity of the cover member itself is improved. For this reason, the rigidity of the housing fitted with the cover member is further improved. vice versa,
The cover member can be made thinner while ensuring the predetermined rigidity of the cover member, and the geared motor as a whole can be reduced in weight.

Further, since the rib is a fitting portion and the cover member is in contact with the inner peripheral surface of the housing opening at the outer peripheral surface of the rib, the contact area between the cover member and the housing increases, and the rib acts on the housing. And the deformation and distortion of the housing can be more effectively prevented.

As described above, in the geared motor according to the second aspect, by ensuring the rigidity of the housing without increasing the weight, the meshing accuracy of the gears can be ensured, the generation of abnormal noise can be prevented, and the durability can be improved. Is improved.

According to a third aspect of the present invention, in the geared motor according to the second aspect, the rib has a radial elasticity on a surface of the cover member opposite to a surface facing the bottom surface of the housing. It is characterized in that it is formed so as to be deformable, and the housing bottom surface has a taper with a small diameter.

In the geared motor according to the third aspect, the radially deformable rib is formed on the surface of the cover member on the side not facing the housing bottom surface, and the housing bottom surface has a taper with a small diameter. For example, when the cover member is fitted to the inner peripheral surface of the housing opening by press fitting, the rib is elastically deformed corresponding to the inner peripheral surface of the housing opening. As a result, the cover member is fitted to the housing while elastically pressing the inner peripheral surface of the housing opening. For this reason, the closed cross section formed integrally with the housing and the cover member is further strengthened, and the rigidity of the housing is further improved.

If the tapered small diameter portion is configured to be slightly smaller than the inner diameter of the inner peripheral surface of the housing opening, the cover member can be easily fitted into the housing opening by, for example, press fitting.

Thus, in the geared motor according to the third aspect, by ensuring the rigidity of the housing more securely without increasing the weight, the meshing accuracy of the gears can be ensured, the generation of abnormal noise can be prevented, and the durability can be improved. The performance is improved.

A geared motor according to a fourth aspect of the present invention is the geared motor according to any one of the first to third aspects, wherein the housing has a stepped portion opposed to an opening surface in a cylindrical portion thereof. The cover member is engaged with the step portion while being fitted to the housing,
It is characterized by:

In the geared motor according to the fourth aspect, the stepped portion facing the opening surface is formed in the cylindrical portion of the housing, and the cover member is engaged with the stepped portion while being fitted to the housing. When the reaction force acts on the housing from the bearing portion of the output shaft or the attachment portion to the vehicle, the displacement of the fitting position of the cover member is prevented, and the rigidity of the housing is secured. Further, positioning when the cover member is assembled (fitted) to the housing is also facilitated.

As described above, in the geared motor according to the fourth aspect, by ensuring the rigidity of the housing more securely without increasing the weight, the meshing accuracy of the gears can be ensured, and the generation of abnormal noise can be prevented. The durability is improved.

According to a fifth aspect of the present invention, in the geared motor according to any one of the first to fourth aspects, the cover member is made of metal.

In the geared motor according to the fifth aspect, since the cover member is made of metal, the rigidity of the cover member is high,
The rigidity of the housing fitted with the cover member is further improved. In particular, even when used in a high temperature environment (for example, 95 ° C.) that is assumed in a vehicle, the decrease in the elastic modulus of the metal material itself is very small and the rigidity of the cover member is maintained. The reduction in rigidity of the housing in which is fitted is suppressed.

As described above, in the geared motor according to the fifth aspect, the rigidity of the housing is further ensured without increasing the weight, thereby ensuring the gear meshing accuracy and preventing the generation of abnormal noise. In addition, the durability is improved.
In particular, the rigidity of the housing can be ensured even in a high temperature environment.

[0028]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A geared motor 10 according to the present embodiment will be described with reference to FIGS. Figure 1
1 shows a partially cutaway front view of a geared motor 10 according to an embodiment of the present invention. FIG.
1 shows a cross-sectional view along line 2-2 in FIG.

The geared motor 10 includes a motor section 10A and a gear section 10B connected to the motor section 10A. In the yoke 12 of the motor unit 10A,
One end of the armature shaft 16 (motor rotation shaft) of the armature 14 is supported by a bearing (not shown).

The tip of the armature shaft 16 extends into the motor housing 18 of the gear portion 10 B connected to the yoke 12.

On the other hand, in the gear portion 10 B, the worm 20 is connected to the armature shaft 16, and the tip of the worm 20 is supported by the motor housing 18 by the bearing 22. This motor housing 18
Consists of a cylindrical portion 18A and a bottom portion 19A, and an opening 18B
The worm 20 and a worm wheel 24 meshing with the worm 20 are housed therein. This motor housing 18
The cylindrical portion 18A is provided with a cover holding surface 18C having an enlarged inner diameter at an end portion on the opening 18B side and a cover engaging surface 18D formed in a step-like shape as the inner diameter of the cylindrical portion 18A is increased.

The bottom 19A of the motor housing 18
A boss 19C having a boss hole 19B is formed at the center of the boss 19C, and one end of a center shaft 26 is fixed to the boss hole 19B of the boss 19C.

As shown in FIG. 3, the gear portion 10B is
The worm wheel 24 is provided. The worm wheel 24 is formed in a substantially cup shape including a cylindrical portion 24A and a bottom portion 24B, and a worm gear 28 that can mesh with the worm 20 is formed on the outer peripheral portion of the cylindrical portion 24A.
The worm wheel 24 is provided with a support boss 30A having a raised bottom portion 24B and a thicker center portion. The support boss portion 30A has a center shaft 26A.
A shaft hole 30 </ b> B that is slidable around the center shaft 26 with substantially the same diameter as the outside diameter of the center shaft 26 is formed. Further, the support boss 3
A minute projection 30C whose inner surface is along the shaft hole 30B is formed at 0A. Thereby, the worm wheel 24
Is rotatably (slidably) supported in a state where the center shaft 26 is inserted into the shaft hole 30B and the end surface of the boss portion 19C and the end surface of the support boss portion 30A are in contact with each other.
A worm gear 28 formed on the outer peripheral portion of 4B is configured to mesh with the worm 20.

The bottom 24B of the worm wheel 24
, A plurality (three in this embodiment) of engagement projections 32 are formed at equal intervals near the inner peripheral surface of the cylindrical portion 24A.

A cushion rubber 34 is disposed inside the worm wheel 24. Cushion rubber 3
Numeral 4 is formed in a substantially short cylindrical shape, and a plurality of (six in this embodiment) slits 34A and 34B (three in this embodiment) are alternately provided at equal intervals on the outer peripheral portion. The cushion rubber 34 is arranged to be inserted on the bottom 24B in the cylindrical portion 24A of the worm wheel 24 with the engagement projection 32 of the worm wheel 24 inserted into the slit 34A.

The gear section 10B has an output shaft 36. The output shaft 36 is composed of a disk-shaped plate portion 38 and an output gear portion 40 having teeth 40A on an outer peripheral portion, and is integrally formed of resin. A seal holding hole 38A having a diameter larger than the outer diameter of the center shaft 26 and substantially the same diameter as the outer diameter of the convex portion 30C of the worm wheel 24 is formed in the output shaft 36 from the plate portion 38 side.
Support hole 4 having substantially the same diameter as the outer shape of center shaft 26 from the side
0B is formed. The seal holding hole 38A has a depth corresponding to an O-ring 44 described later and communicates with a support hole 40B at an end thereof.
A step 38B is formed at the boundary between A and the support hole 40B. A stepped thick portion 38C is formed at the boundary between the plate portion 38 and the output gear portion 40.
A stepped seal holding surface 38D is formed at the outer peripheral end of C. Further, the seal holding hole 38 of the plate portion 38
A slit 34B of the cushion rubber 34 is provided on the A-side end face.
(Three in this embodiment) engaging pieces 42 corresponding to
Are formed at equal intervals.

As a result, the output shaft 36 is connected to the support hole 40B.
The worm wheel 24 is arranged on the engagement rubber 34 with the center shaft 26 inserted into the cushion rubber 34 and the engagement piece 42 inserted into the slit 34B of the cushion rubber 34.
Is transmitted via the Internet. In this state, the plate portion 38 is disposed in the cylindrical portion 24A of the worm wheel 24, and the end face of the support boss portion 30A of the worm hole 24 and the seal holding hole 3 of the plate portion 38 are formed.
It is configured so that the end face around 8B slides.

Further, in the gear portion 10B, an O-ring 44 is fitted to the center shaft 26. The O-ring 44 is pressed between the outer peripheral surface of the center shaft 26 and the inner peripheral surface of the seal holding hole 38B of the plate portion 38,
The configuration prevents water or the like from entering the motor housing 18 from the sliding surface between the center shaft 26 and the support hole 40B of the output shaft 36. Further, the O-ring 44 is prevented from falling out by being disposed between the step portion 38B of the output shaft 36 and the convex portion 30C of the worm wheel 24 inserted into the seal holding hole 38A in the axial direction of the center shaft 26. It has become so.

Further, a lock washer 46 is fitted to an end of the output gear portion 40 of the center shaft 26,
The worm wheel 24, the output shaft 36 and the like are prevented from falling off.

In this state, a cover plate 48 is attached to the opening 18B of the motor housing 18. The cover plate 48 is made of metal and is formed in a substantially disk shape, and an outlet hole 48A having an inner diameter larger than the outer diameter of the output gear portion 40 is formed at the center thereof. Outside the outlet hole 48A, a stepped short cylindrical portion 48B having substantially the same diameter as the outer diameter of the thick portion 38C of the plate portion 38 extends toward the plate portion 38 (the lower side in FIG. 2). ing. Further, outside the short cylindrical portion 48B, two flat plate portions are sandwiched by an outer peripheral portion of the cover plate 48 with an inclined portion 48C extending toward the opposite side (upper side in FIG. 2) to the side where the plate portion 38 is installed. The outer peripheral portion is formed with a rib 48D as a fitting portion along the outer peripheral surface. The end of the rib 48D facing the bottom 19A of the motor housing 18 (the lower side in FIG. 2) has a cover holding surface 18E of the motor housing 18.
Before being assembled to the motor housing 18, the upper side of FIG. 2 is formed to have a slightly larger diameter so as to have an elastically deformable tapered shape. The cover plate 48 is formed with high rigidity by having the short cylindrical portion 48B, the inclined portion 48C, and the rib 48D.

As shown in detail in FIG. 4A, the cover plate 48 is provided with an opening 18B of the motor housing 18.
Is fitted into the cover holding surface 18C (the inner circumferential surface of the opening 18B) while the outer peripheral surface of the tapered rib 48D is elastically deformed corresponding to the cover holding surface 18C of the motor housing 18. At the same time, the end face on the side where the rib 48D is not formed is arranged so as to engage with the cover engaging face 18D of the motor housing 18.

In this state, the O-ring 50 disposed around the seal holding surface 38D formed on the thick portion 38C of the output shaft 36 is pressed in the radial direction of the cover plate 48 by the inner surface of the short cylindrical portion 48B. Configuration. Thus, intrusion of water or the like into the motor housing 18 from between the output shaft 36 and the cover plate 48 is prevented.

The shaft hole 30B of the center shaft 26 and the worm wheel 24 and the support hole 40A of the output shaft 36
Around the O-rings 44 and 50, between the boss 19C of the motor housing 18 and the support boss 30A of the worm wheel 24, and between the end face of the support boss 30A of the worm hole 24 and the end face of the plate 38. A lubricant (e.g., grease oil) is applied to each of the sliding portions so that they slide smoothly.

Next, the operation of the present embodiment will be described.

In the geared motor 10 having the above structure, when the motor unit 10A is activated and the armature shaft 16 is rotated, the worm wheel 24 meshing with the worm 20 connected to the armature shaft 16 rotates around the center shaft 26. Thus, the rotation of the armature shaft 16 is reduced. The rotational force of the worm wheel 24 is transmitted to the cushion rubber 34 via the engagement projection 32 inserted into the slit 34A of the cushion rubber 34, and the rotational force of the cushion rubber 34 is transmitted to the engagement inserted into the slit 34B of the cushion rubber 34. It is transmitted to the plate portion 38 via the piece 42. Plate part 38 and output gear part 4
0 is formed as an integrated output shaft 36 and always rotates integrally, so that the output gear unit 40 is also rotated by the rotational force transmitted to the plate unit 38 to drive the other system (for example, a power window device). it can.

Here, the cover plate 48 is connected to the motor housing 18 at a rib 48D formed on the outer peripheral surface thereof.
The motor housing 18 and the cover plate 48 form a closed cross section integrally with the cover holding surface 18C (the inner peripheral surface of the opening 18B). In particular, the ribs 48
D has a taper before being attached to the motor housing 18, and the rib 48D is elastically deformed when attached to the motor housing 18, thereby elastically pressing the cover holding surface 18C of the motor housing 18. The closed cross section formed integrally with the cover plate 48 is solid. For this reason, the rigidity of the motor housing 18 is greatly improved, and the deformation and distortion of the motor housing 18 due to the reaction force from the mating system with which the output shaft 36 meshes and the attachment portion to the vehicle are suppressed. Further, the cover plate 48 is connected to the motor housing 1 via the rib 48D.
8 comes into contact with the cover holding surface 18C, so that the contact area with the motor housing 18 increases.
The stress acting on the housing 8 is reduced, and the deformation and distortion of the housing can be more effectively prevented.

The motor housing 1 is used as a strength member.
8 a cover plate 4 for preventing water or the like from entering the inside
Since the number 8 is used, the number of parts does not increase and the geared motor 10 does not become heavy as a whole.

Further, the cover plate 48 is provided with a short cylindrical portion 48B, a rib 48D and an inclined portion 48C, and the rigidity of the cover plate itself is improved. The rigidity of the housing 18 is further improved. Conversely, it is possible to reduce the thickness of the cover plate 48 while securing the predetermined rigidity of the cover plate 48, and it is also possible to reduce the weight of the geared motor 10 as a whole.

Further, the cover plate 48 is fitted on the cover holding surface 18C of the motor housing 18 and the bottom surface thereof covers the cover engaging surface 1 of the motor housing 18.
8D, the displacement of the fitting position between the cover holding surface 18C and the outer surface of the rib 48D when the reaction force from the mating system with which the output shaft 36 meshes or the mounting portion to the vehicle acts on the motor housing 18. Is prevented, and the rigidity of the motor housing 18 is ensured. Also, cover plate 4
Positioning when fitting the motor 8 to the motor housing 18 can be easily performed.

Further, since the cover plate 48 is made of metal, the rigidity of the cover plate 48 itself is further improved, and the cover plate 48 can be used in a high temperature environment (for example, 9
Even at 5 ° C.), the rigidity of the motor housing 18 to which the cover plate 48 is fitted is prevented from decreasing without the rigidity of the cover plate 48 decreasing.

As described above, in the geared motor 10 according to the present embodiment, the rigidity of the motor housing 18 is ensured without increasing the weight, thereby ensuring the meshing accuracy in the gear portion 10B and preventing generation of abnormal noise. And at the same time, the durability can be improved. (Modified example of fitting portion between motor housing and cover plate) In the geared motor 10 according to the above embodiment, the motor housing 1
Although the configuration includes the cover 8 and the cover plate 48, a configuration including a motor housing and a cover plate according to a modified example described below may be employed. Components common to the above-described embodiment are denoted by the same reference numerals as in the above-described embodiment, and description thereof will be omitted.

The geared motor according to the embodiment of the present invention has a motor cover plate 52 shown in FIG.
May be provided.

The cover plate 52 has no ribs on the outer peripheral surface, is fitted on the cover holding surface 18C on the outer peripheral surface 54, and is engaged with the cover engaging surface 18D on its bottom surface. It is. With this configuration, there is no need to provide a rib on the outer peripheral portion of the cover plate 52, and the component can be easily and simply processed.

Further, the geared motor according to the embodiment of the present invention may be configured to include a cover plate 60 shown in FIG.

The cover plate 60 has a substantially U-shape (annular groove shape) which extends to the side (lower side in FIG. 4) facing the motor housing 18 on the outer periphery thereof and has an upper opening in FIG. A rib 62 is provided, and the outer peripheral portion 64 of the rib 62 is elastically brought into contact with the cover holding surface 18C of the motor housing 18, and the bottom surface 66 of the rib 62 is engaged with the cover engaging surface 18D. Thereby, the rigidity of the cover plate 60 is ensured and the space inside the motor housing 18 can be increased in the axial direction. As a result, the geared motor as a whole is increased in rigidity, reduced in thickness, and reduced in weight.

Further, the geared motor according to the embodiment of the present invention has a cover plate 70 shown in FIG.
May be provided.

The cover plate 70 has an outer peripheral surface as shown in FIG.
4 is opened in the cross-sectional view and the lower side of FIG. 4 is opened. A substantially U-shaped (annular groove-shaped) rib 72 is provided, and an opening 18B of the cylindrical portion 18A of the motor housing 18 is provided in the opening of the rib 72.
The side end is configured to be inserted (fitted). That is, the radially outwardly facing inner wall 74A of the rib 72 is in contact with the cover holding surface 18C of the motor housing 18, and the radially inwardly facing inner wall 74B of the rib 72 is in contact with the outer peripheral surface of the cylindrical portion 18A of the motor housing 18. It is supposed to be. Thereby, the motor housing 18 and the cover plate 70 form a stronger closed cross section, and the rigidity of the motor housing 18 is improved.

Further, the geared motor according to the embodiment of the present invention may be configured to include a motor housing 80 and a cover plate 90 shown in FIG.

The motor housing 80 is provided with a groove 82 on the open end face of the cylindrical portion. On the other hand, the cover plate 90 includes a rib 92 formed on the side facing the motor housing 80 along the outer peripheral surface. This rib 92
Is pressed into the groove 82 of the motor housing 80 so that the outer peripheral surface of the rib 92 comes into contact with the radially inward wall surface (circumferential surface) 84A of the groove 82 and the inner peripheral surface of the rib 92 is
Is configured to be in contact with a radially outward wall surface (circumferential surface) 84B. As a result, the motor housing 80 and the cover plate 90 form a stronger closed cross section, thereby effectively suppressing deformation and distortion of the motor housing 80 and increasing the space inside the motor housing 80 in the axial direction. As a result, the rigidity of the geared motor as a whole is increased, and the thickness and the weight are reduced.

It should be noted that the motor housing 18 and the cover plates 48, 5
2, 60, 70 and the motor housing 80
The configuration of the fitting portion between the motor housing 18 and the cover plate 90 is described by way of example, and the present invention is not limited thereto.
It may be configured to fit only on the outer peripheral surface of 8B. Also,
For example, in the configuration of FIG.
The eight ribs 48D may extend to the side of the motor housing 18 facing the cover engagement surface 18D, and the ribs 48D may not have a taper before fitting to the motor housing 18. Furthermore, in the above embodiment, the cover plate 48 and the like are configured to be press-fitted into the opening 18B of the motor housing 18. However, the present invention is not limited to this. It is also possible to adopt a configuration in which after being fitted to the like, it is fixed by heat caulking.

In the above embodiment, the cover plate 48 is made of metal. However, the present invention is not limited to this. The material of the cover plate 48 and the like may be any material that can secure appropriate rigidity. Good.

Further, in the above-described embodiment and each of the modifications, the motor housing 18 is provided with the cover engaging surface 18D. However, the present invention is not limited to this. ) May not be provided. In the above-described embodiment and each of the modifications, the seal member is not arranged between the motor housing 18 and the cover plate 48 and the like. However, the present invention is not limited to this.
For example, a configuration may be adopted in which a part of the cover engagement surface 18D is further formed in a stepped shape, and an O-ring is arranged at this stepped portion.

Further, in the above-described embodiment and each modified example, the geared motor 10 includes the worm wheel 24 slidably rotatable around the center shaft 26 fixed to the motor housing 18 and the output gear portion 40, Although these components are connected so as to be able to transmit rotation via the cushion rubber 34 and the plate portion 38, the present invention is not limited to this. For example, the worm wheel 24 is rotatably supported by the motor housing 18 and the motor An output shaft 36 integrated with a center shaft 26 separately rotatably supported by the housing 18 includes a cushion rubber 34.
Alternatively, the worm wheel 24 may be configured to be driven by the worm wheel 24 via the plate portion 38. Further, the output shaft 36 is not limited to the configuration including the output gear section 40, and may be configured to include, for example, a socket-shaped output fitting section.

[Brief description of the drawings]

FIG. 1 is a partially cutaway plan view showing an entire configuration of a geared motor according to an embodiment of the present invention.

FIG. 2 is a cross-sectional view taken along the line 2-2 of FIG. 1, showing a configuration of a gear unit constituting the geared motor according to the embodiment of the present invention.

FIG. 3 is an exploded perspective view of a gear portion constituting the geared motor according to the embodiment of the present invention.

FIG. 4A is a sectional view showing details of a fitting portion between a motor housing and a cover plate constituting the geared motor according to the embodiment of the present invention, and FIG. 4B is a first view of the fitting portion; (C) is a cross-sectional view showing a second modified example of the fitting portion, (D) is a cross-sectional view showing a third modified example of the fitting portion, and (E) is a sectional view showing a third modified example of the fitting portion. The fourth part of the fitting part
It is sectional drawing which shows the modification of.

[Explanation of symbols]

10 Geared motor 16 Armature shaft (motor rotation shaft) 18 Motor housing (housing) 18B Opening 18C Cover holding surface (radial inward circumferential surface, housing inner peripheral surface) 18D Cover contact surface (step) Reference Signs List 20 worm 24 worm wheel 36 output shaft 48 cover plate (cover member) 48D rib (fitting portion) 52 cover plate (cover member) 54 outer peripheral portion (fitting portion) 60 cover plate (cover member) 62 rib (fitting portion) 70 cover plate (cover member) 72 rib (fitting portion) 80 motor housing (housing) 84A wall surface (radial inward circumferential surface) 84B wall surface (radial outward circumferential surface) 90 cover plate (cover) Member) 92 rib (fitting part)

Continuing from the front page (72) Inventor Hirofumi Sakai 390 Umeda, Kosai-shi, Shizuoka Prefecture Asmo Stock Company In-house F-term (reference) 3D127 DF04 3J009 DA02 DA11 DA16 EA06 EA19 EA32 EB24 FA03 5H605 AA05 BB05 CC01 CC02 CC05 CC08 DD03 EA15 AGG04 5 BB01 BB14 CC01 CC03 DD05 DD09 DD17 EE32 EE36 JJ06 JJ08

Claims (5)

[Claims] 1. A housing which is formed in a bottomed cylindrical shape and accommodates a worm connected to a motor rotation shaft and a worm wheel which meshes with the worm and drives an output shaft, and corresponds to an opening of the housing. It is formed in a disk shape, and is fitted around one or both of a radially inwardly facing circumferential surface and a radially outwardly facing circumferential surface in the vicinity of an opening of the housing at an outer peripheral portion thereof over substantially the entire circumference. A cover member that covers the opening of the housing by being fitted to the housing at the fitting portion, and that supports the opening of the housing in the radial direction. Geared motor. 2. The cover member has an annular rib formed along an outer peripheral surface of the cover member, the rib serving as a fitting portion, and an outer peripheral surface of the rib abutting on an inner peripheral surface of the housing. The geared motor according to claim 1, wherein the geared motor is used. 3. The rib is formed on a surface of the cover member opposite to a surface facing the bottom surface of the housing so as to be elastically deformable in a radial direction, and has a taper having a small diameter on the bottom surface side of the housing. 3. The geared motor according to claim 2, wherein: 4. The housing has a stepped portion facing the opening surface in a cylindrical portion thereof, and the cover member is engaged with the stepped portion while being fitted to the housing. The geared motor according to any one of claims 1 to 3, wherein: 5. The geared motor according to claim 1, wherein the cover member is made of metal.