JPH11215771A - Small type motor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To smoothly support an armature shaft with a minimum number of bearings for stable operation by sporting rotatably one end part of the armature shaft with the first bearing, fitting it at an end cap, and rotatably supporting the other end part of the armature shaft with a second bearing. SOLUTION: An assembly body is formed integrally, with high rigidity, out of a case 2, a yoke and an end cap 6. As a result, first and second bearings 8, 9 are disposed concentrically with an armature shaft 13 without displacement, so that high concentricity can be obtained. Since the armature shaft 13 is supported by the first bearing 8 which is fixed in the shaft hole 2a2 of the gear case part 2a of the case 2 and the second bearing 9 is fixed at the recessed part 6a1 of the end cap 6, the length dimension of the armature shaft 13 is shortened by the two bearings.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a small motor used for driving a window glass or a sunroof lid.

[0002]

2. Description of the Related Art As a small motor for driving a window glass or a sunroof lid, there is known a small motor in which a worm is formed at one end of an armature shaft provided on an armature and a reduction gear meshes with the worm. I have. An armature core is attached to the center of the armature shaft, and a commutator is arranged on the worm side of the armature core.

[0003]

However, in the above-mentioned small motor, a reduction gear and a worm of an armature shaft are arranged in a gear case, and a marmature is arranged in a motor case screwed to the gear case. One end of the armature shaft is supported in the gear case, while the other end of the armature shaft is supported in the motor case. And a stress acts to tilt the motor case with respect to the gear case. Therefore, the bending of the armature shaft is suppressed by arranging three bearings at one end on the worm side, the other end on the opposite side to the worm, and between the commutator and the worm. However, there is a problem that the entire length of the armature shaft including the lengths supported by the armatures is increased. In addition, when bending stress is applied to the armature shaft, the motor case is inclined with respect to the gear case, so that the center of the armature shaft and the bearing is displaced, and the friction resistance between the armature shaft and the bearing increases, resulting in lower efficiency. Or
There is a problem that abnormal noise is generated, and it has been a problem to solve these problems.

[0004]

SUMMARY OF THE INVENTION It is an object of the present invention to provide a small-sized motor capable of performing a stable operation by smoothly supporting an armature shaft with a small number of bearings.

[0005]

Configuration of the Invention

[0006]

According to a first aspect of the present invention, there is provided a small motor having a gear case formed at one end and a motor case protruding from the gear case integrated at the other end. And a yoke attached to the inside of the motor case portion of the case, a magnet arranged inside the yoke, and an end cap coupled to the projecting tip of the motor case portion of the case,
An armature that is arranged on the inner periphery of the magnet, has an armature shaft with a worm formed in the gear case portion of the case, and has a commutator attached to the end cap side, and one end of the armature shaft attached to the gear case portion of the case A first bearing rotatably supporting the part, attached to the end cap,
A second bearing rotatably supporting the other end of the armature shaft, rotatably supported by a gear case portion of the case and meshed with a worm of the armature shaft;
The present invention is characterized in that a configuration is provided in which a speed reduction unit is connected to an output shaft via a damper.

In the small motor according to the second aspect of the present invention, a shaft hole is formed in the gear case portion of the case in the axial direction of the armature shaft, and a recess is formed in the center of the end cap in the axial direction of the armature shaft. Wherein the first bearing is a plain bearing or a ball bearing mounted on the end of the shaft hole, and the second bearing is a plain bearing or a ball bearing mounted on the recess of the end cap. It is characterized by doing.

In the small motor according to the third aspect of the present invention, the motor case portion of the case is provided with first and second yoke support plates which are respectively opposed to each other, and the yoke is provided with the first and second yoke support plates. The yoke support plate is provided with a plate portion sandwiched and supported between the yoke support plates.

In the small motor according to a fourth aspect of the present invention, the yoke has a plurality of retaining pieces formed on the gear case portion side of the cylindrical yoke main body. It is characterized in that a gear case side yoke fixing portion to which each of the retaining pieces is locked is formed.

In the small motor according to a fifth aspect of the present invention, the yoke has a plurality of fixing pieces formed on the end cap side of the yoke main body, and the end caps are respectively engaged with the fixing pieces of the yoke. The end cap side yoke fixing portion is formed.

[0011] In the small motor according to claim 6 of the present invention, the reduction portion has a first reduction gear meshed with the worm of the armature shaft, and is meshed with the first reduction gear and connected to the damper. A second reduction gear is provided.

[0012]

In the small motor according to the first aspect of the present invention, the armature shaft comprises a case, a yoke,
While being arranged in a highly rigid assembly formed by the end cap, the axis accuracy is secured by the case and the end cap, and the first and second bearings rotatably support the shaft. Therefore, even if bending force is applied to the armature shaft due to the worm of the armature shaft meshing with the deceleration portion, no misalignment occurs between the armature shaft and the first and second bearings. , Smoothly supported only by the second bearing,
The length of the armature shaft may be short, and the frictional resistance between the armature shaft and the first and second bearings does not increase.

In the small motor according to a second aspect of the present invention, the armature shaft is a first bearing which is a slide bearing or a ball bearing having one end attached to an end of a shaft hole formed in a gear case portion of the case. , While the other end is rotatably supported by a second bearing, which is a slide bearing or a ball bearing attached to a recess formed in the end cap. Therefore, in addition to the function of the first aspect, it is not necessary to use a bearing with a mounting member such as a centering bearing to support the armature shaft.

In the small motor according to the third aspect of the present invention, the yoke is supported by being sandwiched between the first and second yoke support plates facing the motor case portion of the case. Therefore, in addition to the operation of the first aspect, the yoke has a strong double structure by the first yoke support plate and the second yoke support plate.

In the small motor according to a fourth aspect of the present invention, the yoke has a retaining piece locked to a gear case side yoke fixing portion formed on a gear case portion of the case. Therefore, in addition to the function of the third aspect, the yoke is integrally and firmly connected to the gear case portion of the case.

In the small motor according to the fifth aspect of the present invention, the fixing pieces of the yoke are respectively locked to end cap side yoke fixing portions formed on the end cap. Therefore, in addition to the function of the fourth aspect, the yoke that is firmly integrated integrally with the gear case portion of the case is firmly connected to the end cap.

In the small motor according to the present invention, the rotation of the armature shaft is reduced by the first reduction gear, and then the rotation of the first reduction gear is reduced by the second reduction gear. To the output shaft. Therefore, in addition to the effect of the first aspect, large deceleration is performed without increasing the advance angle of the worm of the armature shaft.

[0018]

1 to 4 show a first embodiment of a small motor according to the present invention, which is used for driving a window glass.

The illustrated small motor 1 mainly includes a case 2, a yoke 3, a first magnet 4, a second magnet 5, an end cap 6, an armature 7, a first bearing 8, a second bearing 9, It comprises a speed reduction unit 10 and an output shaft 11.

The case 2 is integrally formed with a gear case 2a and a motor case 2b.

The gear case 2a of the case 2 has a substantially rectangular gear case main body 2a1 and a round shaft hole 2a.
The shaft hole 2a2 has an end plate portion 2a3 formed in an oval shape at one end side of the motor case portion 2b side, and a motor case portion 2b at the other end side. The first bearing 8 is fixed to the closed end of the shaft hole 2a2.

The first bearing 8 is a ball bearing, and includes a worm 1 of an armature shaft 13 provided in the armature 7.
The end on the 3a side is rotatably supported.

A gear housing 2a4 is formed in the gear case 2a of the case 2 so as to communicate with the shaft hole 2a2. The gear accommodating portion 2a4 is formed in a hole shape connecting two circles, and a pivot support shaft support portion 2a5 is formed near the shaft hole 2a2 of the gear accommodating portion 2a4. The pivot 12 is fixed. Pivot 1
2 includes a first reduction gear 1 that forms a part of the reduction unit 10.
4 is rotatably inserted.

The first reduction gear 14 has a large-diameter tooth portion 14a.
And the small-diameter tooth portion 14b are integrally formed in two steps, and the large-diameter tooth portion 14a is formed in the shaft hole 2a2 with another part of the reduction portion 10 formed on the armature shaft 13 provided in the armature 7. The first reduction gear 14 reduces the rotation of the armature shaft 13 by one step because the first reduction gear 14 meshes with the worm 13a. The small-diameter tooth portion 14b of the first reduction gear 14 is meshed with a tooth portion 15a formed on the second reduction gear 15 that forms the remaining part of the reduction portion 10.

An output shaft support 2a6, which is a bearing, is formed at a position away from the shaft hole 2a2 of the gear housing 2a4, and an O-ring (O-ring) 16 is fitted in the output shaft support 2a6. The attached output shaft 11 is rotatably inserted.

The output shaft 11 has a proximal end fixed to the hub 17 and a distal end protruding outside the gear case 2a, and is coupled to a window glass elevating mechanism (not shown). The hub 17 is connected to a damper 18 described later.

The second reduction gear 15 has a damper receiving portion 15b formed on the inner peripheral side of the tooth portion 15a. A damper 18 made of an elastic material is provided in the second reduction gear 15 in this damper receiving portion 15b. Are combined.

In the speed reduction section 10, the armature shaft 1
3, the rotation of the armature shaft 13 is reduced by one step by the large-diameter tooth portion 14a of the first reduction gear 14, and the small-diameter tooth portion 14b of the first reduction gear 14
And the teeth 15a of the second reduction gear 15, the rotation of the armature shaft 13 is reduced in two steps, and the rotation of the second reduction gear 15 is given to the output shaft 11 via the damper 18. At this time, the reduction ratio of the worm 13a of the armature shaft 13 and the large-diameter tooth portion 14a of the first reduction gear 14 is large, and the outer diameter of the large-diameter tooth portion 14a of the first reduction gear 14 Also, since the distance between the shafts between the first reduction gear 14 and the second reduction gear 15 is smaller, the armature shaft 13
The large deceleration is performed without increasing the advance angle of the worm 13a, so that the outer dimensions of the speed reduction unit 10 do not increase and the operation noise does not increase.

The first, second, third, and fourth gear case side yoke fixing portions 2a7, 2a8, 2a9, 2a are provided on the side of the end plate 2a3 on the gear case portion 2a of the case 2.
10 are provided.

First gear case side yoke fixing portion 2a7
Is formed in a rectangular groove shape above the front surface of the end plate portion 2a3.

Second gear case side yoke fixing portion 2a8
Are formed in a rectangular through-hole shape below the front surface of the end plate portion 2a3. This second gear case side yoke fixing portion 2
a8 penetrates into the gear housing 2a4 of the gear case 2a.

Third gear case side yoke fixing portion 2a9
Are formed in a rectangular groove shape above the rear surface of the end plate portion 2a3.

Fourth gear case side yoke fixing portion 2a10
Is formed in a rectangular groove shape below the rear surface of the end plate portion 2a3. The first gear case side yoke fixing portion 2a7 and the third gear case side yoke fixing portion 2a9 are formed by an end plate portion 2a3.
Are arranged in a pair on the upper side.

A first retaining piece 3a5 provided on the yoke 3, which will be described later, is fitted into the first gear case side yoke fixing portion 2a7, and the first retaining piece 3a is provided on the back side of the end plate portion 2a3.
a5 is caulked.

A second retaining piece 3a6 provided on the yoke 3 described later is inserted into the second gear case side yoke fixing portion 2a8, and then the gear housing portion 2a4 of the gear case portion 2a is inserted.
Inside, the second retaining piece 3a6 is crimped.

A third retaining piece 3a7 provided on the yoke 3 to be described later is fitted into the third gear case side yoke fixing portion 2a9, and the third retaining piece 3a is provided on the back side of the end plate portion 2a3.
a7 is caulked.

Fourth gear case side yoke fixing portion 2a10
Then, after a fourth retaining piece 3a8 provided on the yoke 3 described later is fitted, the fourth retaining piece 3a8 is crimped on the back side of the end plate portion 2a3.

First yoke support plates 2b1 and 2b2 are formed on the motor case 2b of the case 2 and project from the upper and lower ends of the end plate 2a3 of the gear case 2a.

First and second yoke support plates 2b1, 2b2
As shown in FIG. 4, each of the gears protrudes in the same direction as the hole direction of the shaft hole 2a2 of the gear case portion 2a. Inside the first and second yoke support plates 2b1 and 2b2, first and second yoke contact surfaces 2b3 and 2b4 that are curved substantially the same as a curved portion of a yoke body 3a provided in the yoke 3 described later. Are formed respectively. First and second yoke contact surfaces 2b3, 2b
The inner diameter dimension formed by the yoke 3 is slightly smaller than the outer diameter dimension of a yoke main body 3a provided in the yoke 3, which will be described later. Therefore, the yoke 3 is supported by the first and second yoke contact surfaces 2b3 and 2b4. .

First and second yoke support plates 2b1, 2b2
The first and second end cap contact surfaces 2 that come into contact with an end cap 6 described later are opened at the front end.
b5 and 2b6 are formed respectively. The yoke 3 is accommodated between the first and second yoke support plates 2b1 and 2b2.

The yoke 3 is provided with an oval cylindrical thin yoke main body 3a made of a magnetic material. The yoke 3 is formed by winding yoke forming obtained by winding a base material into a cylindrical shape, press forming obtained by pressing the base material, or the like.

As shown in FIG. 4, the yoke main body 3a of the yoke 3 has first and second flat plate portions 3a at a front portion and a rear portion.
1, 3a2 is provided in each pair,
A pair of first and second curved plate portions 3a3 and 3a4 are provided at an upper portion and a lower portion, respectively. First and second flat plate portions 3
The width between a1 and 3a2 is substantially the same as the width of the first and second yoke support plates 2b1 and 2b2, and the outer diameter formed by the first and second curved plate portions 3a3 and 3a4 is As described above, the first and second yoke support plates 2b1, 2b2 are slightly smaller than the inner diameter formed by the first and second yoke contact surfaces 2b3, 2b4.

As shown in FIG. 4, first, second, third, and fourth retaining pieces 3a5, 3a6, 3a7, 3a are provided on the yoke main body 3a on the end plate 2a3 side of the gear case 2a.
8 are provided.

The first retaining piece 3a5 is located above the first flat plate portion 3a1 of the yoke main body 3a.
From the gear case portion 2a to an end plate portion 2a3 of the gear case portion 2a.

The first retaining piece 3a5 is arranged corresponding to the first gear case side yoke fixing portion 2a7 formed on the end plate portion 2a3 of the gear case portion 2a.
When the yoke main body 3a is inserted between the first yoke contact surface 2b3 of the first yoke support plate 2b1 and the second yoke contact surface 2b4 of the second yoke support plate 2b2, the first gear case side After being fitted into the yoke fixing part 2a7, it is crimped on the back side of the end plate part 2a3.

The second retaining piece 3a6 is provided below the first flat plate portion 3a1 of the yoke main body 3a.
From the gear case portion 2a to an end plate portion 2a3 of the gear case portion 2a.

The second retaining piece 3a6 is arranged corresponding to the second gear case side yoke fixing portion 2a8 formed on the end plate portion 2a3 of the gear case portion 2a.
When the yoke main body 3a is inserted between the first yoke contact surface 2b3 of the first yoke support plate 2b1 and the second yoke contact surface 2b4 of the second yoke support plate 2b2, the second gear case side After being inserted into the yoke fixing portion 2a8,
It is crimped on the gear housing 2a4 side. Second retaining piece 3a
6 may be omitted, in which case the gear case portion 2a
The second gear case side yoke fixing portion 2a is attached to the end plate portion 2a3
8 is not formed.

The third retaining piece 3a7 is located above the second flat plate portion 3a2 of the yoke main body 3a.
From the gear case portion 2a to an end plate portion 2a3 of the gear case portion 2a.

The third retaining piece 3a7 is arranged corresponding to the third gear case side yoke fixing portion 2a9 formed on the end plate portion 2a3 of the gear case portion 2a.
When the yoke main body 3a is inserted between the first yoke contact surface 2b3 of the first yoke support plate 2b1 and the second yoke contact surface 2b4 of the second yoke support plate 2b2, the third gear case side After being fitted into the yoke fixing part 2a9, it is crimped on the back side of the end plate part 2a3.

The fourth retaining piece 3a8 is located below the second flat plate portion 3a2 of the yoke main body 3a.
From the gear case portion 2a to an end plate portion 2a3 of the gear case portion 2a.

The fourth retaining piece 3a8 is arranged corresponding to the fourth gear case side yoke fixing portion 2a10 formed on the end plate portion 2a3 of the gear case portion 2a, so that the yoke main body 3a is in the first position. Of the first yoke support plate 2b1
Contact surface 2b3 and second yoke support plate 2b2
When inserted between the second yoke contact surfaces 2b4, the fourth
And then crimped on the back side of the end plate 2a3.

In the yoke 3, the yoke main body 3a is inserted between the first yoke contact surface 2b3 of the first yoke support plate 2b1 and the second yoke contact surface 2b4 of the second yoke support plate 2b2. First, third and fourth retaining pieces 3a5, 3a
7 and 3a8 are fitted into the first, third and fourth gear case side yoke fixing portions 2a7, 2a9 and 2a10, and are caulked on the back side of the end plate portion 2a3, respectively, while the second retaining piece 3a6 is Second gear case side yoke fixing portion 2a8
The first and second curved plate portions 3a3 and 3a4 of the yoke main body 3a are caulked in the gear housing portion 2a4 after being inserted into the first and second yoke support plates 2b1 and 2b1.
2b2, the first and second yoke contact surfaces 2b3, 2b4 sandwich the first yoke abutment surfaces 2b2 and 2b2, and are integrally and firmly assembled.
Even if a bending stress is applied to the yoke body 3a,
The bending stress is tolerated, and there is no displacement or inclination with respect to the gear case portion 2a. Therefore, the first bearing 8 fixed to the closed side end of the shaft hole 2a2 is arranged concentrically with respect to the armature shaft 13 arranged inside the yoke 3 without deviation.

As shown in FIG. 4, first, second, third, and fourth fixing pieces 3a9, 3a10, and 3a are provided on the yoke main body 3a on the side opposite to the end plate 2a3 of the gear case 2a.
11 and 3a12 are provided, respectively.

The first fixing piece 3a9 is located above the first flat plate portion 3a1 of the yoke main body 3a.
And a rectangular projection protruding toward an end cap 6 to be described later in the axial direction of an armature shaft 13 to be described later. The first fixing piece 3a9 is provided with an end cap 6 described later.
After being fitted into the first end cap side yoke fixing portion 6a2 provided in the above, the end cap 6 is crimped and fixed on the front side.

The second fixing piece 3a10 is connected to the yoke main body 3a.
The first flat plate portion 3a is located below the first flat plate portion 3a1.
The armature shaft 13 is formed so as to protrude in a rectangular shape from 1 toward an end cap 6 described later in the axial direction of an armature shaft 13 described later. The second fixing piece 3a10 is provided with a second end cap side yoke fixing portion 6a3 provided in the end cap 6 described later.
And is caulked and fixed on the front side of the end cap 6.

The third fixing piece 3a11 is connected to the yoke main body 3a.
Above the second flat plate portion 3a2, the second flat plate portion 3a
The projection 2 is formed in a rectangular shape in the axial direction of an armature shaft 16 described later from 2 toward an end cap 6 described later. The third fixing piece 3a11 is provided with a third end cap side yoke fixing portion 6a4 provided in the end cap 6 described later.
And is caulked and fixed on the front side of the end cap 6.

The fourth fixing piece 3a12 is connected to the yoke main body 3a.
Below the second flat plate portion 3a2, the second flat plate portion 3a
The projection 2 is formed in a rectangular shape in the axial direction of an armature shaft 16 described later from 2 toward an end cap 6 described later. The fourth fixing piece 3a12 is provided with a fourth end cap side yoke fixing portion 6a5 provided in the end cap 6 described later.
And is caulked and fixed on the front side of the end cap 6.

An end cap 6 is attached to the first, second, third and fourth fixing pieces 3a9, 3a10, 3a11 and 3a12 of the yoke 3.

The end cap 6 has a round hole-shaped recess 6a in the center of an end cap body 6a formed in an oval plate shape.
1 is formed, and a second bearing 9 is formed in the recess 6a1.
Has been fixed. The second bearing 9 is a ball bearing, and rotatably supports an end of the armature shaft 13 provided on the armature 7 on the side opposite to the worm 13a.

As shown in FIG. 3, the end cap 6 has first, second, third, and fourth end cap side yoke fixing portions 6a on side portions of the end cap body 6a.
2, 6a3, 6a4, and 6a5 are provided, respectively.

First end cap side yoke fixing portion 6a
2 is formed in a rectangular groove shape on the upper side of the front surface of the end cap body 6a.

Second end cap side yoke fixing portion 6a
3 is formed in a rectangular groove shape on the lower side of the front surface of the end cap body 6a.

Third end cap side yoke fixing portion 6a
4 is formed in a rectangular groove shape above the rear surface of the end cap body 6a.

Fourth end cap side yoke fixing portion 6a
5 is formed in a rectangular groove shape below the rear surface of the end cap body 6a. First end cap side yoke fixing portion 6a2 and third end cap side yoke fixing portion 6
The second end cap side yoke fixing portion 6a3 and the fourth end cap side yoke fixing portion 6a4 are arranged in a pair below the end cap main body 6a. Have been.

The first end cap side yoke fixing portion 6a
2 includes a first fixing piece 3a9 provided on the yoke 3 described above.
The first fixing piece 3a9 is crimped on the front side of the end cap main body 6a after having been fitted.

Second end cap side yoke fixing portion 6a
3 includes a second fixing piece 3a1 provided on the yoke 3 described above.
After the 0 is inserted, the second fixing piece 3a10 is swaged on the front side of the end cap body 6a.

Third end cap side yoke fixing portion 6a
4 includes a third fixing piece 3a1 provided on the yoke 3 described above.
After the first fixing piece 3 is fitted, the third fixing piece 3a11 is swaged on the front side of the end cap body 6a.

Fourth end cap side yoke fixing portion 6a
5 includes a fourth fixing piece 3a1 provided on the yoke 3 described above.
After the second fixing piece 2 is inserted, the fourth fixing piece 3a12 is swaged on the front side of the end cap body 6a.

In the end cap 6, first, second, third, and fourth end cap-side fixing portions 6a2, 6a3, 6
The first, second, third, and fourth fixing pieces 3a9, 3a10, 3a11, and 3a12 of the yoke 3 are fitted into the a4 and 6a5, and then are caulked on the front side of the end cap body 6a. 3 and is securely assembled integrally with the yoke 3. Therefore, the concave portion 6a of the end cap 6 is
The second bearing 9 fixed to 1 is concentrically arranged without displacement. A holder base 19 is arranged on the rear surface side of the end cap 6.

In the holder base 19, a round commutator insertion hole 19a1 is formed at the center of an oval plate-shaped holder base body 19a, and a first commutator insertion hole 19a1 is formed outside the commutator insertion hole 19a1. , The second brush boxes 19a2, 19a3 are formed facing each other. A first brush spring 20 and a first brush 22 are housed in the first brush box 19a2, and a second brush spring 21 and a second brush 23 are housed in the second brush box 19a3. I have. The first and second brushes 22, 23 are pressed toward the center of the commutator insertion hole 19a1 by the first and second brush springs 20, 21, respectively. The first and second brushes 22, 23 are respectively connected to external control circuits through terminals (not shown).

On the other hand, first and second magnets 4 and 5 are fixed to the inside of the yoke main body 3a of the yoke 3 so as to face each other. The first and second magnets 4 and 5 have N poles and S poles magnetized on the inner peripheral sides facing each other. An armature 7 is arranged inside the first and second magnets 4 and 5.

The armature 7 includes an armature shaft 13, an armature core 24, a commutator 25,
An armature coil 26 is provided.

An armature core 24 is fixed to the armature shaft 13 at substantially the center of a round rod-shaped shaft body 13b.
The commutator 2 is on the opposite side of the worm 13a through
5 is fixed. The armature core 24 has a winding portion 24 a having a predetermined number of slots, and the commutator 25 has a winding portion 2 a of the armature core 24.
4a are provided with the same number of commutator pieces 25a, and the armature coils 26 are wound around the winding portions 24a of the armature core 24, respectively.
Are electrically connected to the respective commutator pieces 25a.

The commutator piece 2 of the commutator 25
The first and second brushes 22 and 23 disposed on the holder base 19 and opposed to each other are brought into contact with 5a so as to be electrically connectable.

In the armature 7, on the armature shaft 13, through the armature core 24, the worm 1
Since the commutator 25 is disposed on the side opposite to 3a, there is no possibility that the lubricating oil applied to the worm 13a or the first reduction gear 14 will scatter to the commutator 25 side, and no electrical failure will occur. .

As described above, the yoke 3 is inserted between the first yoke contact surface 2b3 of the first yoke support plate 2b1 and the second yoke contact surface 2b4 of the second yoke support plate 2b2. First, third and fourth retaining pieces 3a5, 3a7, 3
a8 is the first, third and fourth gear case side yoke fixing portions 2
a7, 2a9, and 2a10, and then the end plate 2
The second yoke fixing portion 2a8 is fitted into the second gear case side yoke fixing portion 2a8 and then crimped in the gear housing portion 2a4, while being crimped on the back side of the y3 main body 3a. 1, second curved plate portion 3a
3, 3a4 are first and second yoke support plates 2b1, 2b2
The first and second yoke contact surfaces 2b3 and 2b4 sandwich the yoke 3 integrally and firmly with the case 2, and the first, second, third and fourth yokes 3
After the fixing pieces 3a9, 3a10, 3a11, 3a12 of the end cap 6 are fitted into the first, second, third, and fourth end cap side fixing portions 6a2, 6a3, 6a4, 6a5 of the end cap 6, the end cap body 6a The end cap 6 is integrally and firmly attached to the yoke 3 by being caulked on the front side of the. Therefore, Case 2,
Since the high rigid assembly is integrally formed by the yoke 3 and the end cap 6, the first and second bearings 8,
9 is concentrically arranged on the armature shaft 13 without deviation, to obtain high coaxiality, and the first fixed in the shaft hole 2a2 of the gear case portion 2a of the case 2.
Of the armature shaft 13 by the bearing 8 and the second bearing 9 fixed to the concave portion 6a1 of the end cap 6.
Is supported, the length of the armature shaft 13 is reduced by the two bearings.

The worm 13a of the armature shaft 13 is meshed with the large-diameter tooth portion 14a of the first reduction gear 14, so that when the rotation of the armature shaft 13 is given to the first reduction gear 14, the armature is rotated. Even when a bending stress is applied to the shaft 13, the armature shaft 13 does not bend because the case 2, the yoke 3, and the end cap 6 have high rigidity integrally, and the armature shaft 13 and the first and second armatures are not bent. The frictional resistance between the bearings 8 and 9 does not increase.

The small motor 1 having such a structure is as follows.
The case 2 is mounted inside the door panel, and the output shaft 11
Is connected to the window glass via the glass lifting mechanism,
The first and second brushes 22, 23 are electrically connected to a control circuit and mounted on a vehicle body.

When the window open switch provided in the control circuit is turned on when the window glass is in the fully closed state, the potential of the power source is applied to the first brush 22 and the second brush 23 is turned on. When grounded, the armature coil 2
6 is excited, the armature shaft 13 rotates forward by electromagnetic induction caused by the magnetic force generated by the armature coil 26 and the magnetic force generated by the first and second magnets 4 and 5, and the forward rotation of the armature shaft 13 is performed. First,
The output shaft 1 is reduced through the second reduction gears 14 and 15.
It is converted to 1 forward rotation and the window glass opens.

When the window glass reaches the fully opened position and collides with the vehicle body, the rotation of the output shaft 11 is restricted, so that the damper 18 is elastically deformed, and at the same time, the first and the second are rotated.
Is cut off, the window glass stops at the fully open position.

With the window glass in the fully open position,
When the window close switch of the control circuit is turned on, the electric potential of the power supply is applied to the second brush 23, and when the first brush 22 is grounded, the armature coil 26 is provided for each slot of the armature core 24. The magnetic force generated by the armature coil 26 when excited,
The armature shaft 13 rotates in the reverse direction by electromagnetic induction caused by the magnetic force generated by the first and second magnets 4 and 5, and the reverse rotation of the armature shaft 13 causes the first and second rotations.
Is reduced through the reduction gears 14 and 15 and is converted into reverse rotation of the output shaft 11, and the window glass is closed.

When the window glass reaches the fully closed position and collides with the vehicle body, the output shaft 11 is restrained from rotating in the reverse direction, so that the damper 18 is elastically deformed, and at the same time, the output shaft 11 is resiliently deformed. Since the energization is cut off, the window glass stops at the fully closed position.

When the armature shaft 13 rotates forward and backward, the worm 13a of the armature shaft 13
When the first gear 14 meshes with the first reduction gear 14, a reaction force is generated and a bending stress is applied to the armature shaft 13. However, the case 2, the yoke 3, and the end cap 6 integrally form a highly rigid assembly. As a result, the yoke 3 is not displaced or tilted with respect to the gear case portion 2a due to the bending stress applied to the armature shaft 13, and the armature is formed only by the first and second bearings 8, 9. The shaft 13 is smoothly supported.

FIG. 5 shows a second embodiment of a small motor according to the present invention, which is also used to drive a window glass.

In the small motor 1 of the second embodiment, the case 2
The shaft hole 2a2 of the gear case portion 2a formed in
The end is closed by the attachment of a stopper 27, the first thrust receiving plate 28 abuts on the stopper 27, and the first bearing 8 is mounted near the first thrust receiving plate 28. On the other hand, the second thrust receiving plate 29 is fixed to the concave portion 6a1 formed in the end cap 6,
The second bearing 9 is mounted near the second thrust receiving plate 29. In this case, the first and second bearings 8, 9 are plain bearings. And the armature shaft 13
The first sphere 30 is rotatably accommodated at one end of the worm 13a side, and the first sphere 30 is in contact with the first thrust receiving plate 28, while the end cap 6 of the armature shaft 13 is A second sphere 3 at the other end
1 is rotatably accommodated, and the second sphere 31 is in contact with the second thrust receiving plate 29. Other parts are first
The description is omitted because it is the same as the embodiment.

Also in this case, the case 2, the yoke 3, and the end cap 6 integrally form a highly rigid assembly. Therefore, the first case fixed in the shaft hole 2a2 of the gear case portion 2a of the case 2 is formed. The bearing 8 and the second bearing 9 fixed to the concave portion 6a1 of the end cap 6 are coaxially arranged on the armature shaft 13 without displacement, and a high coaxiality is obtained. When the worm 13a of the armature shaft 13 meshes with the first reduction gear 14 during the reverse rotation, even if a reaction force is generated and a bending stress is applied to the armature shaft 13, the bending stress applied to the armature shaft 13 causes , The yoke 3 is not displaced or inclined with respect to the gear case portion 2a.
The armature shaft 13 is smoothly supported by only the bearings 8 and 9. In this case, since the first and second bearings 8 and 9 are sliding bearings, the cost is more advantageous than in the first embodiment.

[0087]

As described above, according to the compact motor of the first aspect of the present invention, when the armature shaft is disposed in a highly rigid assembly formed of the case, the yoke, and the end cap. Along with the case and the end cap, the shaft center accuracy is ensured, and the case and the end cap are rotatably supported by the first and second bearings. Therefore, even if bending force is applied to the armature shaft due to the worm of the armature shaft meshing with the deceleration portion, no misalignment occurs between the armature shaft and the first and second bearings. , The second bearing alone, and the armature shaft may be short in length.
The frictional resistance between the bearings does not increase.
Therefore, there is an excellent effect that the armature shaft can be smoothly supported by a small number of bearings and stable operation can be performed.

According to the small motor according to the second aspect of the present invention, the armature shaft is a slide bearing or a ball bearing having one end attached to an end of a shaft hole formed in a gear case portion of the case. While the other end is rotatably supported by a second bearing which is a slide bearing or a ball bearing attached to a recess formed in the end cap. Therefore, in addition to the effect of the first aspect, there is an excellent effect that it is not necessary to use a bearing with a mounting member such as a centering bearing to support the armature shaft.

According to the small motor according to the third aspect of the present invention, the yoke is supported by being sandwiched between the first and second yoke support plates facing the motor case portion of the case. Therefore, in addition to the effect of the first aspect, the yoke has an excellent effect that a strong double structure can be obtained by the first yoke support plate and the second yoke support plate.

According to the small motor according to the fourth aspect of the present invention, the retaining yoke is locked to the gear case side yoke fixing portion formed on the gear case portion of the case. Therefore, in addition to the effect of the third aspect, there is an excellent effect that the yoke is integrally and firmly connected to the gear case portion of the case.

According to the small motor according to the fifth aspect of the present invention, the fixing pieces of the yoke are respectively locked to the end cap side yoke fixing portions formed on the end cap. Therefore, in addition to the effect of the fourth aspect, the yoke integrally and firmly attached to the gear case portion of the case has an excellent effect of being firmly connected to the end cap.

According to the small motor according to the sixth aspect of the present invention, after the rotation of the armature shaft is reduced by the first reduction gear, the rotation of the first reduction gear is reduced by the second reduction gear. To the output shaft via a damper. Therefore, in addition to the effect of the first aspect, there is an excellent effect that large deceleration is performed without increasing the advance angle of the worm of the armature shaft.

[Brief description of the drawings]

FIG. 1 is a longitudinal sectional front view of a first embodiment of a small motor according to the present invention.

FIG. 2 is a vertical sectional left side view of the small motor shown in FIG.

FIG. 3 is a right side view of the small motor shown in FIG. 1;

4 is an external perspective view illustrating an assembling relationship between a case, a yoke, and an end cap in the small motor illustrated in FIG. 1;

FIG. 5 is a vertical sectional front view of a second embodiment of the small motor according to the present invention.

[Explanation of symbols]

Reference Signs List 1 small motor 2 case 2a gear case portion 2a2 shaft hole 2a7 (gear case side yoke fixing portion) first gear case side yoke fixing portion 2a8 (gear case side yoke fixing portion) second gear case side yoke fixing portion 2a9 (gear case side yoke fixing portion ) Third gear case side yoke fixing part 2a10 (Gear case side yoke fixing part) Fourth gear case side yoke fixing part 2b Motor case part 2b1 First yoke support plate 2b2 Second yoke support plate 3 Yoke 3a Yoke main body 3a3 ( (Plate portion) 1st curved plate portion 3a4 (plate portion) 2nd curved plate portion 3a5 (preventing piece) first retaining piece 3a6 (preventing piece) second retaining piece 3a7 (preventing piece) third retaining piece 3a8 (Retaining piece) Fourth retaining piece 3a9 (Fixing piece) First fixing piece 3a10 (Fixing piece) Second fixing piece 3a11 (Fixing Piece) third fixing piece 3a12 (fixing piece) fourth fixing piece 4 (magnet) first magnet 5 (magnet) second magnet 6 end cap 6a1 recess 6a2 (end cap side yoke fixing portion) first End cap side yoke fixing part 6a3 (End cap side yoke fixing part) Second end cap side yoke fixing part 6a4 (End cap side yoke fixing part) Third end cap side yoke fixing part 6a5 (End cap side yoke fixing part) ) Fourth end cap side yoke fixing portion 7 Armature 10 Reduction portion 11 Output shaft 13 Armature shaft 13a Worm 14 First reduction gear 15 Second reduction gear 18 Damper 25 Commutator

Claims (6)

[Claims] 1. A case in which a gear case portion is formed on one end side and a motor case portion protruding from the gear case portion is integrally formed on the other end side; An attached yoke, a magnet arranged inside the yoke, an end cap coupled to a protruding tip of a motor case part of the case, and an end cap arranged on an inner peripheral part of the magnet, inside a gear case part of the case. An armature having an armature shaft with a commutator attached to the end cap side, and an armature attached to a gear case portion of the case, the first armature rotatably supporting one end of the armature shaft. A bearing, attached to the end cap, and the other end of the armature shaft A second bearing rotatably supported; and a reduction unit rotatably supported by a gear case portion of the case, meshed with a worm of the armature shaft, and coupled to an output shaft via a damper. A small motor characterized by the following. 2. A shaft hole is formed in the gear case portion of the case in the axial direction of the armature shaft, and a concave portion is formed in the center of the end cap in the axial direction of the armature shaft. 2. The bearing according to claim 1, wherein the bearing is a ball bearing mounted on an end of the shaft hole, and the second bearing is a slide bearing or a ball bearing mounted on a recess of the end cap.
The small motor according to the above. 3. A motor case portion of the case is provided with first and second yoke support plates which are respectively opposed to each other,
2. The small motor according to claim 1, wherein the yoke is provided with plate portions that are sandwiched and supported between the first and second yoke support plates. 3. 4. A yoke has a plurality of retaining pieces formed on a side of a gear case portion of a cylindrical yoke main body, and a gear case in which the retaining pieces of the yoke are respectively engaged with the gear case portion of the case. The small motor according to claim 3, wherein a side yoke fixing portion is formed. 5. The yoke has a plurality of fixing pieces formed on the end cap side of the yoke main body, and the end cap has end cap side yoke fixing portions to which the fixing pieces of the yoke are respectively locked. The small motor according to claim 4, wherein the small motor is formed. 6. The reduction unit includes a first reduction gear meshed with the worm of the armature shaft, and a second reduction gear meshed with the first reduction gear and coupled to a damper. The small motor according to claim 1, wherein: