JP2000316256A - Motor with speed reduction mechanism - Google Patents

Abstract

PROBLEM TO BE SOLVED: To reduce size and weight by setting an outer diameter smaller than a first shaft being formed by a worm in a second shaft where an armature core and a commutator are fixed. SOLUTION: A first shaft 9a with first and second worms 10a and 10b, and a second shaft 9b with an outer diameter being smaller than the first shaft 9a are formed in an armature shaft 9 for reducing the dead weight of the armature shaft 9. Also, on the second shaft 9b with a smaller diameter than the first shaft 9a of the armature shaft 9, an armature core 13, a commutator 14, and an armature coil 17 are arranged, the outer diameter of the armature core 13 is reduced, and the outer diameter of a motor yoke 2 is reduced, thus reducing the size and weight.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a motor with a speed reduction mechanism for reducing the rotation of an armature shaft provided on an armature that rotates by energization and driving a load from an output shaft.

[0002]

2. Description of the Related Art As a motor with a speed reduction mechanism for decelerating the rotation of an armature shaft provided on an armature rotated by energization and driving a load from an output shaft, an armature shaft provided on an armature built in a motor yoke includes: First and second worms are formed in the gear case, respectively, and the large-diameter side teeth of the first and second counter gears are meshed with the first and second worms respectively. Is known in which each of the small-diameter side teeth is meshed with a wheel gear, and the wheel gear is connected to an output shaft. On the armature shaft,
First and second worms are formed at one end thereof, an armature core and a commutator are arranged at the center thereof, and the center is rotatably supported by a first bearing mounted on a gear case. Are rotatably supported by a second bearing mounted inside an end cover coupled to the end of the motor yoke.

[0003]

In the motor with a speed reduction mechanism described above, if the armature shaft of the armature has a single outer diameter, it is assumed that the outer diameter of the motor yoke is reduced for downsizing. However, since the outer diameter of the commutator does not become smaller, it is necessary to arrange the brush, the brush spring, and the holder base in a narrow space between the motor yoke having the reduced inner diameter and the commutator having the outer diameter not reduced. Becomes difficult,
There was a problem that miniaturization could not be achieved.

A worm shaft having first and second worms formed on an armature shaft, and a core shaft formed separately from the worm shaft and having a smaller outer diameter than the worm shaft. When the armature core and the commutator are attached to the core shaft and the core shaft is press-fitted to the worm shaft, the worm shaft press-fitted to the core shaft after the first bearing is assembled to the gear case. Difficult to insert. This is because the first bearing is arranged near the worm shaft of the core shaft. Therefore, when assembling, the first bearing is arranged between the core shaft and the worm shaft before being attached to the core shaft. After press-fitting the worm shaft and inserting the worm shaft into the gear case,
However, since the above-mentioned bearing is mounted on the gear case, there is a problem that extremely complicated work is required. In this case, the first bearing rotatably supports the core shaft having an outer diameter smaller than the worm shaft. For example, the first bearing is configured to withstand a large bending load applied to the armature shaft when the load is locked. The axial length of the shaft must be increased. As a result, the first armature having a large length cannot shorten the entire length of the armature shaft, and cannot be downsized. There was a problem.

Further, in the motor with a speed reduction mechanism, a single flat holder base is arranged inside the end cover at the end of the motor yoke, and a circuit breaker is placed on the holder base on the end cover side. Since it is mounted so as to protrude, the length from the holder base to the second bearing mounted inside the end cover must be increased by the entire length of the circuit breaker, and as a result, the second bearing There has been a problem that the entire length of the armature shaft inserted into the armature cannot be shortened, and the size cannot be reduced.

[0006]

An object of the present invention is to provide a motor with a speed reduction mechanism.
It is an object of the present invention to provide a motor with a speed reduction mechanism that can be reduced in size and weight.

[0007]

Configuration of the Invention

[0008]

According to a first aspect of the present invention, there is provided a motor with a speed reduction mechanism, a motor yoke, a gear case connected to the motor yoke, a magnet disposed inside the motor yoke, and a first yoke. An armature shaft in which a shaft portion and a second shaft portion having an outer diameter smaller than the first shaft portion are integrally formed, a worm formed in the first shaft portion of the armature shaft, and an inner peripheral portion of the magnet. An armature core arranged and fixed to the second shaft portion of the armature shaft, a commutator fixed near the armature core of the second shaft portion, and an electric wire wound around the armature core and electrically connected to the commutator. Armature coil connected, brush arranged outside of the commutator so as to be electrically connectable to the commutator, and gear case A counter gear rotatably supported and meshed with the worm of the armature shaft, a wheel gear meshed with the counter gear, and an output shaft fixed to the wheel gear and coupled to a load. Features.

In the motor with a speed reduction mechanism according to a second aspect of the present invention, the motor yoke, the gear case connected to one end of the motor yoke, and the motor yoke are formed independently, and the motor yoke is formed at the other end of the motor yoke. An armature shaft integrally formed with a coupled end cover, a magnet disposed inside the motor yoke, a first shaft portion and a second shaft portion having an outer diameter smaller than the first shaft portion; A worm formed on the first shaft portion of the armature shaft;
Attached to the gear case, the first armature shaft
A first bearing rotatably supporting the shaft of the armature; a second bearing attached to the end cover and rotatably supporting a second shaft of the armature shaft; and a second bearing disposed on the inner periphery of the magnet. An armature core fixed to the second shaft portion of the armature shaft, a commutator fixed near the armature core on the second bearing side of the second shaft portion, and electrically connectable to the commutator outside the commutator And a counter gear wound around an armature core and electrically connected to a commutator; a counter gear rotatably supported by a gear case and meshed with a worm of an armature shaft; and a counter gear. A wheel gear engaged with the wheel gear, and an output shaft fixed to the wheel gear and coupled to a load. It is characterized in that the content was.

In a motor with a speed reduction mechanism according to a third aspect of the present invention, the motor yoke, the gear case connected to one end of the motor yoke, and the motor yoke are formed independently, and the motor yoke is connected to the other end of the motor yoke. An armature shaft integrally formed with a coupled end cover, a magnet disposed inside the motor yoke, a first shaft portion and a second shaft portion having an outer diameter smaller than the first shaft portion; A worm formed on the first shaft portion of the armature shaft;
Attached to the gear case, the first armature shaft
A first bearing rotatably supporting the shaft of the armature; a second bearing attached to the end cover and rotatably supporting a second shaft of the armature shaft; and a second bearing disposed on the inner periphery of the magnet. An armature core fixed to the second shaft portion of the armature shaft, a commutator fixed near the armature core on the second bearing side of the second shaft portion, and electrically connectable to the commutator outside the commutator And a counter gear wound around an armature core and electrically connected to a commutator; a counter gear rotatably supported by a gear case and meshed with a worm of an armature shaft; and a counter gear. A second gear, an output shaft fixed to the wheel gear and coupled to a load, and a second bearing The first plate portion is disposed outside the commutator along the axial direction of the second shaft portion and away from the first plate portion to support the brush and to have a circuit breaker mounting portion. A holder base having the formed second plate portion and mounted inside the end cover, and a circuit breaker protruding and mounted on the circuit breaker mounting portion of the second plate portion of the holder base toward the second bearing. It is characterized by having the structure provided with.

[0011] In the motor with a speed reduction mechanism according to a fourth aspect of the present invention, the first shaft is inserted into the first bearing on the second shaft side of the first and second worms. A first bearing insertion portion is formed, and a second bearing insertion portion to be inserted into the second bearing is formed on the second shaft portion on a side opposite to the first shaft portion, and the first shaft portion is formed. The armature core mounting portion is formed on the side of the armature core mounting portion, and the commutator mounting portion is formed on the second bearing insertion portion side of the armature core mounting portion.

In the motor with a speed reduction mechanism according to a fifth aspect of the present invention, a pair of brush holding portions for movably holding the brushes toward the commutator and holding the brushes respectively are provided on the second plate portion of the holder base. It is characterized in that it is formed.

[0013]

In the motor with a speed reduction mechanism according to the first aspect of the present invention, the outer diameter of the second shaft portion to which the armature core and the commutator are fixed is smaller than that of the first shaft portion in which the worm is formed. Has become. Therefore, the outer diameter of the armature core is smaller and the outer diameter of the motor yoke is smaller than that in the case of using a single outer diameter armature shaft.

In the motor with a reduction mechanism according to claims 2 and 4 of the present invention, the first bearing rotatably supports the first shaft portion on which the worm is formed, so that the first bearing receives bending stress applied to the armature shaft. Oppose enough. Therefore, it is not necessary to increase the length of the first bearing as compared with the case of supporting a core shaft having an outer diameter smaller than that of the worm shaft. The first bearing reduces the overall length of the armature shaft.

In the motor with a speed reduction mechanism according to the third and fifth aspects of the present invention, the circuit breaker is disposed apart from the first plate portion of the holder base in the axial direction of the second shaft portion corresponding to the commutator. Attached to the second plate portion. Therefore, the projecting amount of the circuit breaker toward the end cover is reduced, and the length from the commutator of the second shaft to the second bearing is shortened.
In addition to the operation described above, the overall length of the armature shaft is further reduced.

[0016]

BEST MODE FOR CARRYING OUT THE INVENTION

[0017]

1 to 6 show an embodiment of a motor with a speed reduction mechanism according to the present invention.

The illustrated motor 1 with a reduction mechanism mainly includes a motor yoke 2, a first magnet 3, a second magnet 4, an end cover 5, a holder base 6, a circuit breaker 7, a gear case 8, a first shaft portion. Armature shaft 9 having a shaft 9a and a second shaft 9b, worm 1
0, a first bearing 11, a second bearing 12, an armature core 13, a commutator 14, a first brush 15, a second
Brush 16, armature coil 17, first counter gear 18, second counter gear 19, wheel gear 2
0, an output shaft 21, and a worm 10, a first counter gear 18, a second counter gear 19, and a wheel gear 20 constitute a reduction mechanism.

The motor yoke 2 has a motor yoke main body 2a in the form of an oval tube having a height L1 on the long side shown in FIG. 1 and a width L2 on the short side shown in FIG.
The motor yoke main body 2a has a gear case connecting portion 2a1 formed at one end thereof, and the motor yoke main body 2a has an end cover connecting portion 2a2 formed at the other end thereof.

The motor yoke 2 includes a motor yoke main body 2
The first and second magnets 3 and 4 are attached to the inside of a. An armature core 13 is arranged on the inner peripheral side of the first and second magnets 3 and 4 in a non-contact manner.
The first and second magnets 3 and 4 generate mutually opposing magnetic forces on the inner peripheral side.

The end cover 5 is connected to an end cover connecting portion 2a2 of the motor yoke 2. As shown in FIG. 4, the end cover 5 has a disc-shaped end cover body 5a for closing the other end of the motor yoke body 2a.
And an outer plate portion 5b extending from the end cover body 5a in the cylinder direction of the motor yoke 2. The end cover 5 has a length L in the cylinder direction of the motor yoke 2.
3

At the center of the end cover body 5a, a second bearing 12 is mounted inside. The second bearing 12 rotatably supports the other end of the second shaft 9 b of the armature shaft 9.

Inside the outer plate portion 5b, a holder base 6 is provided.
Is installed. As shown in FIG. 4, the holder base 6 has a first plate portion 6a and a first plate portion 6a.
a length L4 in the axial direction of the armature shaft 9 from
A second plate portion 6b disposed only on the armature core 13 side is provided integrally with the second plate portion 6b, and a commutator insertion hole 6c is formed in a central portion.

The first plate portion 6a is provided with an end cover main body 5a.
The first plate 6a is disposed near a second bearing 12 attached to the first terminal 22,
Second terminals 23 are respectively mounted.

The first terminal 22 has a first pigtail connecting portion 22a, a first capacitor connecting portion 22b, and a first external connecting portion (not shown).
The first pigtail connecting portion 22a and the first capacitor connecting portion 22b are arranged so as to protrude from the first plate portion 6a.
The first external connection part is arranged on the lower surface of the second plate part 6b.

The second terminal 23 has a second pigtail connecting portion 23a, a second capacitor connecting portion 23b, and a circuit breaker connecting portion 23c, respectively. The second pigtail connecting portion 23a is connected to the second pigtail connecting portion 23a. The capacitor connecting portion 23b is disposed so as to protrude above the first plate portion 6a. The circuit breaker connecting portion 23c is connected to the second plate portion 6b.
And protrudingly arranged on the circuit breaker mounting portion 6b3 formed at the bottom.

One end of a first pigtail 24 is electrically connected to the first pigtail connecting portion 22a of the first terminal 22, and the other end of the first pigtail 24 is connected to the first pigtail. It is electrically connected to the brush 15.

One end of a second pigtail 25 is electrically connected to the second pigtail connecting portion 23a of the second terminal 23, and the other end of the second pigtail 25 is connected to the second pigtail 25a. It is electrically connected to the brush 16.

The first capacitor connection 22b of the first terminal 22 and the second capacitor connection 23b of the second terminal 23 have first and second capacitors and resistors (not shown) for absorbing surge. The terminals 22 and 23 are electrically connected in parallel.

The first and second brush holding portions 6b1 and 6b2 formed in rectangular holes are formed on the second plate portion 6b so as to face each other with the commutator insertion portion 6c as a center.
The first brush 15 is inserted into the first brush holder 6b1, and the second brush 16 is inserted into the second brush holder 6b2.
Is inserted. The first and second brushes 15, 16 are
The first and second brush springs 28 and 29 are pressed toward the center of the commutator insertion portion 6c and electrically connected to the commutator 14, respectively.

A circuit breaker mounting portion 6b3 is formed on the second plate portion 6b. The first and second terminals 7a, 7b provided on the circuit breaker 7 are formed on the circuit breaker mounting portion 6b3. Are respectively attached.

The circuit breaker 7 is a PTC thermistor, the first terminal 7a of which is electrically connected to a second lead wire (not shown) on the lower surface of the second plate portion 6b. Are electrically connected to the circuit breaker connecting portion 23c of the second terminal 23 on the second plate portion 6b. A first lead wire (not shown) is electrically connected to a first external connection portion of the first terminal 22 on a lower surface of the second plate portion 6b. The first and second leads are
It is electrically connected to an external motor control circuit (not shown).

The circuit breaker 7 has a main body 7c having a length L5 since the first and second terminals 7a and 7b are fitted from the lower surface side of the second plate portion 6b, respectively.
Are slightly protruded below the first plate portion 6a in FIG.

In the holder base 6, since the second plate portion 6b is disposed at a distance L4 in the direction away from the end cover 5 in the cylinder direction of the motor yoke 2, the second plate portion 6b is located at an end from the first plate portion 6a. The distance to the cover 5 is smaller than in the conventional case where the circuit breaker 7 is mounted on a single flat holder base. Therefore, the length from the commutator 14 to the second bearing 12 in the second shaft portion 9b provided on the armature shaft 9 is reduced. The length of the end cover 5 in the cylinder direction of the motor yoke 2 is also smaller than that of a conventional one in which the circuit breaker 7 is mounted on a single flat holder base.

In the holder base 6, a conductive circuit passing through the first lead wire, the first terminal 22, the first pigtail 24, the first brush 15, the second brush 16, the second pigtail 25, Second terminal 23, second terminal 7b of circuit breaker 7, circuit breaker 7
And a conductive circuit passing through the second lead wire.

The gear case 8 has an end portion of the main body 8a connected to a gear case connecting portion 2a1 of the motor yoke 2.
In the main body 8a, a round hole-shaped armature shaft insertion portion 8b is formed in the center portion, and a reduction mechanism housing portion 8c communicated with the armature shaft insertion portion 8b.
Are formed. The reduction mechanism housing portion 8c is covered with a gear case cover 36.

A first bearing 11 is provided at an end of the armature shaft insertion portion 8b of the gear case 8 on the motor yoke 2 side.
Are mounted by press fitting. The first bearing 11 is
The first shaft portion 9a of the armature shaft 9 inserted through the armature shaft insertion portion 8b is rotatably supported. The first bearing 11 has a length L6 in the axial direction of the armature shaft 9.

The reduction mechanism housing portion 8c of the gear case 8 includes:
The first and second counter gears 18 and 19 and the wheel gear 20 are housed respectively.

The first counter gear 18 is rotatably supported by a first pivot 30 fixed to the lower side of the armature shaft 9 in FIG. 1 in the reduction mechanism accommodating portion 8c. In the counter gear 18, a first small-diameter tooth portion 18a and a first large-diameter tooth portion 18b are integrally formed in two stages. The first small-diameter tooth portion 18a is a wheel gear 2
The first large-diameter tooth portion 18b is meshed with the first worm 10a formed on the first shaft portion 9a of the armature shaft 9.

The second counter gear 19 is rotatably supported by a second pivot 31 fixed to the upper side of the armature shaft 9 in FIG. 1 in the reduction mechanism accommodating portion 8c. In the counter gear 19, a second small-diameter tooth portion 19a and a second large-diameter tooth portion 19b are integrally formed in two stages. The second small-diameter tooth portion 19a is a wheel gear 2
The second large-diameter tooth portion 19b is meshed with the second worm 10b formed on the first shaft portion 9a of the armature shaft 9.

Further, a third bearing 32 is attached to the gear case 8 below the armature shaft 9 in FIG.
The output shaft 21 is rotatably supported. A hub 33 is fixed to the output shaft 21 in the reduction mechanism housing 8c. A rubber damper 34 is fixed to the hub 33, and the damper 34 is connected to the wheel gear 20. The output shaft 21 is connected to a load such as a window glass or a sunroof lid.

The wheel gear 20 has teeth 20a meshed with the first and second small-diameter teeth 18a and 19a of the first and second counter gears 18 and 19 described above.

On the other hand, the armature shaft 9 has the first
The shaft portion 9a and the second shaft portion 9b are integrally formed.

A first worm 10a and a second worm 10b constituting the worm 10 are formed on the first shaft portion 9a and have a length L7. First
The worm 10a is twisted right and is disposed at the center of the first shaft portion 9a, and the second worm 10b is twisted left and is disposed at the tip of the first shaft portion 9a. First
Is engaged with the first large-diameter tooth portion 18b of the first counter gear 18, and the second worm 10b is
The second large-diameter tooth portion 19b of the counter gear 19 of FIG. At this time, the first and second worms 10a, 10a
b is the characteristic of the wheel gear 20 shown in FIG.
A lead angle of 4 degrees to 6 degrees between the teeth 20a is selected. Due to the advance angle, even if the window glass or sunroof lid connected to the output shaft 21 is forcibly opened by an external force, the wheel gear 20, the first,
The armature shaft 9 does not rotate due to the external force applied from the second counter gears 18 and 19, and security is achieved.

The first shaft portion 9a has a first bearing insertion portion 9a1 formed at the base end on the side of the second shaft portion 9b. The first bearing insertion portion 9a1 is rotatably supported by being inserted into the first bearing 11. First shaft 9
a is a first worm 10a, as shown in FIG.
Each of the second worm 10b and the first bearing insertion portion 9a1 has a uniform outer diameter dimension d1.

As shown in FIG. 3, the second shaft portion 9b has an outer diameter d2 which is almost half of the outer diameter d1 of the first shaft portion 9a, and is slightly smaller than the first shaft portion 9a. The armature core mounting portion 9b1 is formed on the second shaft portion 9b on the first shaft portion 9a side, which is one end portion side, and the armature core mounting portion is formed on the second shaft portion 9b. A commutator mounting portion 9b is provided on the other end side of 9b1.
2 is formed, and a second bearing insertion portion 9b3 is formed on the other end side of the commutator mounting portion 9b2.

An armature core 13 is fixed to the armature core mounting portion 9b1 of the second shaft portion 9b.
A commutator 14 is fixed to the commutator mounting portion 9b2 of the second shaft portion 9b. The armature core 13 has an outer diameter d3. The armature core 13 has a number of winding portions 13a corresponding to the number of slots.
Are formed. The commutator 14 has an outer diameter d
The commutator 14 is formed with the same number of commutator pieces 14a as the winding portions 13a of the armature core 13. And commutator 1
4 and armature core 13 have commutator pieces 14
a, and an armature coil 17 wound around the winding portion 13a. First shaft 9a, second shaft 9b, armature core 1
3. An armature 35 is constituted by the commutator 14, and the armature coil 17.

In the armature 35, the armature shaft 9 has a first shaft portion 9a having first and second worms 10a and 10b, and a second shaft portion having an outer diameter smaller than that of the first shaft portion 9a. 9b.
The weight of the armature shaft 9 is smaller than that of a conventional one using an armature shaft having a single outer diameter.

In the armature 35, an armature core 13, a commutator 14, and an armature coil 17 are provided on a second shaft 9b having an outer diameter smaller than that of the first shaft 9a.
Are arranged, the outer diameter of the second shaft 9
The largest outer diameter at the portion b, that is, the outer diameter d3 of the armature core 13, and this outer diameter d3
Is smaller than a conventional one in which an armature core, a commutator and an armature coil are arranged on an armature shaft having a uniform outer diameter. Since the outer diameter of the armature core 13 is reduced, the inner and outer diameters of the first and second magnets 3 and 4 disposed outside the armature core 13 are also reduced. The height L1 on the long side and the width L2 on the short side of the motor yoke 2 to which the magnets 3 and 4 are attached are also reduced, and the outer shape of the motor yoke 2 is reduced.

In the armature 35, since the armature core 13 is disposed on the second shaft portion 9b having an outer diameter smaller than that of the first shaft portion 9a, the armature is mounted on an armature shaft having a uniform outer diameter. Since the inner diameter of the shaft press-fitting portion 13b of the armature core 13 is smaller than that of the conventional one in which the core is disposed, the outer peripheral portion 13c of the winding portion 13a of the armature core 13 is moved from the bottom portion 13c.
Since the depth dimension up to d increases, the volume of the winding portion 13a can be increased. As a result, the winding portion 13a
Since the diameter of the winding of the armature coil 17 wound around and the number of windings can be increased, the magnetic force generated from the armature coil 17 increases, and the torque can be improved.

In the armature 35, since the commutator 14 is disposed on the second shaft 9b having an outer diameter smaller than that of the first shaft 9a, the outer diameter d4 of the commutator 14 is uniform. It is smaller than the conventional one in which the commutator is arranged on an armature shaft having dimensions. Therefore, the commutator 14 has a small outer diameter, so that the peripheral speed at the time of rotation decreases, so that the first and second brushes 15 contacting the commutator piece 14a.
The brush sound generated from the brush 16 is reduced.

When the load is locked, the output shaft 2
1, first counter gear 18, second counter gear 1
9, a large bending load is applied to the first and second shaft portions 9a and 9b via the wheel gear 20, the first worm 10a, and the second worm 10b, but the first bearing 11 The first shaft portion 9 having an outer diameter dimension d1 larger than the portion 9b and in which the first and second worms 10a and 10b are formed.
Since a is supported, it is possible to sufficiently oppose the bending stress.

In the armature 35, since the second plate portion 6b of the holder base 6 is disposed apart from the end cover 5 in the cylinder direction of the motor yoke 2 by a length L4, the circuit breaker is simple. Since the distance from the first plate portion 6a of the holder base 6 to the end cover 5 is smaller than that of the conventional one mounted on a single flat holder base, the second armature shaft 9 has The length of the shaft 9b from the commutator 14 to the other end is reduced, and the end cover 5 is also reduced in length.

The motor 1 with a speed reduction mechanism having such a structure
The end cover 5 is attached to the motor yoke 2 to which the first and second magnets 3 and 4 are attached.
The armature 35 is inserted into the inner peripheral portions of the magnets 3 and 4 with the second bearing insertion portion 9b3 of the second shaft portion 9b first, and the first shaft portion 9a protruding from the motor yoke 2 is disposed. Armature shaft insertion portion 8b of gear case 8
Is inserted into. At this time, since the first bearing 11 is already attached to the end of the armature shaft insertion portion 8b of the gear case 8, the first shaft portion 9a is connected to the first bearing 9a.
And the second worm 10b of the first shaft portion 9a is inserted into the second large-diameter tooth portion 19 of the second counter gear 19.
b, the first worm 10a of the first shaft portion 9a is engaged with the second large-diameter tooth portion 18b of the first counter gear 18, respectively, and the first bearing insertion portion 9a1 of the first shaft portion 9a is engaged. Is inserted into the first bearing 11, the motor yoke 2 is connected to the gear case 8, and assembly is performed.

When the open switch provided in the motor control circuit is turned on, the voltage of the power supply is applied to the first lead, and the second lead is connected to the ground.
, First terminal 22, first pigtail 24, first brush 15, commutator piece 14a of commutator 14, armature coil 17, commutator piece 14a of commutator 14, second brush 1
6, the second pigtail 25, the second terminal 23, the second terminal 7b of the circuit breaker 7, the first terminal 7a of the circuit breaker 7, the current of the power supply flows through the second lead wire, and from the armature core 13. A magnetic force is generated, and the armature 35 starts rotating forward due to electromagnetic induction generated by the magnetic force generated from the armature core 13 and the magnetic forces generated by the first and second magnets 3 and 4.

The first and second shaft portions 9a and 9b are rotated forward by the forward rotation of the armature 35, and the first and second counter gears 1 are rotated by the first and second worms 10a and 10b.
8 and 19 are rotated in reverse, and the first and second counter gears 1
The reverse rotation of 8, 19 causes the wheel gear 20 to rotate forward and the output shaft 21 to rotate forward, thereby driving the window glass and sunroof lid to open.

When the close switch provided in the motor control circuit is turned on, the voltage of the power supply is applied to the second lead and the first lead is connected to ground. A current flows, the output shaft 21 is rotated in the reverse direction, and the window glass and the sunroof lid are driven to close.

As described above, the armature shaft 9
A first shaft portion 9a having first and second worms 10a and 10b, and a second shaft portion 9b having an outer diameter smaller than that of the first shaft portion 9a. The armature shaft 9 has its own weight reduced.

Further, the armature core 13, the commutator 14, and the armature coil 17 are arranged on the second shaft portion 9b having an outer diameter smaller than the first shaft portion 9a of the armature shaft 9. Since the outer diameter of the first and second magnets 3 and 4 is also reduced, the inner and outer diameters of the first and second magnets 3 and 4 disposed outside the armature core 13 are also reduced. , A length dimension L1 on the longer side and a width dimension L2 on the shorter side of the motor yoke 2 to which the motor yoke 4 is attached.
Are also reduced, and the outer shape of the motor yoke 2 is reduced.

Since the armature core 13 is disposed on the second shaft portion 9b having a smaller outer diameter than the first shaft portion 9a of the armature shaft 9, the armature shaft 13 has a uniform outer diameter. The depth from the outer edge 13c to the bottom 13d at the winding portion 13a of the armature core 13 is reduced by the smaller inner diameter of the shaft press-fitting portion 13b of the armature core 13 as compared with the conventional one in which the armature core is arranged. So that the winding part 1
The volume of 3a can be increased. As a result, the winding diameter of the armature coil 17 wound around the winding portion 13a can be increased or the number of windings can be increased, so that the magnetic force generated from the armature coil 17 increases, and the torque can be improved. I can do it.

Further, on the second shaft portion 9b having an outer diameter smaller than that of the first shaft portion 9a of the armature shaft 9,
By arranging the commutator 14, the peripheral speed when the commutator 14 rotates is reduced, and therefore, the brush noise generated from the first and second brushes 15, 16 contacting the commutator piece 14a is reduced.

Further, when the load is locked, the output shaft 21, the first counter gear 18, the second counter gear 19, the wheel gear 20, the first worm 1
0a and a large bending load is applied to the first and second shaft portions 9a and 9b via the second worm 10b.
1 can be of small length dimension by sufficiently opposing its bending stress, and thus the armature shaft 9
Of the first shaft portion 9a becomes shorter.

Further, the second plate portion 6b of the holder base 6 is disposed at a distance L4 from the first plate portion 6a in the direction away from the end cover 5 in the cylinder direction of the motor yoke 2. Accordingly, the size of the circuit breaker 7 protruding from the holder base 6 toward the end cover 5 is reduced, so that the length from the commutator 14 of the second shaft portion 9b to the other end is reduced, and the end cover 5 is also It will be a short length.

[0064]

As described above, according to the motor with the speed reduction mechanism according to the first aspect of the present invention, the second shaft portion to which the armature core and the commutator are fixed has the worm-formed first shaft portion. The outer diameter is smaller than that of the shaft portion. Therefore, the outer diameter of the armature core is smaller and the outer diameter of the motor yoke is smaller than that in the case of using a single outer diameter armature shaft. Therefore, there is an excellent effect that the motor yoke having a small outer diameter can be reduced in size and weight.

According to the motor with the speed reduction mechanism according to the second and fourth aspects of the present invention, the first bearing rotatably supports the first shaft portion on which the worm is formed, so that the bending on the armature shaft is performed. Resists stress well. Therefore, the length of the first bearing is smaller than that of supporting the core shaft whose outer diameter is smaller than that of the worm shaft. With this bearing, the overall length of the armature shaft is reduced. Therefore, there is an excellent effect that the armature shaft having a small weight can be reduced in size and weight.

According to the motor with a reduction mechanism according to claims 3 and 5 of the present invention, the circuit breaker is separated from the first plate portion of the holder base in the axial direction of the second shaft portion in correspondence with the commutator. It is attached to the arranged second plate portion. Therefore, the projecting amount of the circuit breaker toward the end cover is reduced, and the length from the commutator of the second shaft to the second bearing is shortened.
In addition to the effect described above, the overall length of the armature shaft is further reduced. Therefore, there is an excellent effect that the armature shaft having a small weight can be reduced in size and weight.

[Brief description of the drawings]

FIG. 1 is a partially broken front view illustrating an internal structure of an embodiment of a motor with a speed reduction mechanism according to the present invention.

FIG. 2 is a longitudinal sectional side view around an output shaft in the motor with a speed reduction mechanism shown in FIG. 1;

FIG. 3 is a front view of an armature used for the motor with a speed reduction mechanism shown in FIG. 1;

FIG. 4 is a sectional view around a commutator in the motor with a speed reduction mechanism shown in FIG. 1;

FIG. 5 is an external perspective view of a holder base used in the motor with a speed reduction mechanism shown in FIG. 1;

FIG. 6 is a characteristic diagram of a lead angle between a worm and a wheel gear used in the motor with a speed reduction mechanism shown in FIG. 1;

[Explanation of symbols]

 Reference Signs List 1 motor with reduction mechanism 2 motor yoke 3 (magnet) first magnet 4 (magnet) second magnet 5 end cover 6 holder base 6a first plate 6b second plate 6b1 (brush holding unit) first (Brush holding portion) 2nd brush holding portion 6b3 circuit breaker mounting portion 7 circuit breaker 8 gear case 9 armature shaft 9a first shaft portion 9a1 first bearing insertion portion 9b second shaft portion 9b1 armature Core mounting part 9b2 Commutator mounting part 9b3 Second bearing insertion part 10a (worm) First worm 10b (worm) Second worm 11 First bearing 12 Second bearing 13 Armature core 14 Commutator 15 (Brush) 1st brush 16 (brush) 2nd brush 17 Over Mature coil 18 (counter gear) the first counter gear 19 (counter gear) second counter gear 20 wheel gear 21 the output shaft

 ──────────────────────────────────────────────────続 き Continued on the front page F term (reference) 3J009 DA17 EA06 EA19 EA32 EB17 EC02 FA14 5H607 BB01 BB14 CC03 CC05 DD01 DD02 DD03 DD08 DD09 DD19 EE32 FF01 GG01

Claims (5)

[Claims] A motor yoke; a gear case coupled to the motor yoke; a magnet disposed inside the motor yoke; a first shaft and a first shaft having a smaller outer diameter than the first shaft. 2
An armature shaft integrally formed and rotatably supported by the motor yoke and the gear case; a worm formed on a first shaft portion of the armature shaft; and an inner peripheral portion of the magnet. An armature core fixed to the second shaft portion of the armature shaft; a commutator fixed to the second shaft portion near the armature core; and an armature core wound around the armature core and fixed to the commutator. An armature coil electrically connected, a pair of brushes arranged outside the commutator so as to be electrically connectable to the commutator, rotatably supported by the gear case, and meshed with a worm of the armature shaft; A counter gear, and a wheel meshed with the counter gear. A motor with a reduction mechanism, comprising: a gear wheel; and an output shaft integrally fixed to the wheel gear and coupled to a load. 2. A motor yoke; a gear case connected to one end of the motor yoke; an end cover formed independently of the motor yoke and connected to the other end of the motor yoke; A magnet disposed inside the yoke, a first shaft and a second shaft having an outer diameter smaller than that of the first shaft.
An armature shaft formed integrally with the shaft portion; a worm formed on the first shaft portion of the armature shaft; and a rotatable support for the first shaft portion of the armature shaft attached to the gear case. A first bearing, a second bearing attached to the end cover and rotatably supporting a second shaft portion of the armature shaft, a second bearing disposed on an inner peripheral portion of the magnet, and a second bearing of the armature shaft; An armature core fixed to the shaft portion of the second shaft portion; a commutator fixed to the armature core on the second bearing side of the second shaft portion; and an electrically connectable outside of the commutator to the commutator. And a pair of brushes wound around the armature core and electrically connected to the commutator Armature coil, a counter gear rotatably supported by the gear case, meshed with the worm of the armature shaft, a wheel gear meshed with the counter gear, fixed to the wheel gear, and coupled to a load. A motor with a speed reduction mechanism, comprising: 3. A motor yoke; a gear case connected to one end of the motor yoke; an end cover formed independently of the motor yoke and connected to the other end of the motor yoke; A magnet disposed inside the yoke, a first shaft and a second shaft having an outer diameter smaller than that of the first shaft.
An armature shaft formed integrally with the shaft portion; a worm formed on the first shaft portion of the armature shaft; and a rotatable support for the first shaft portion of the armature shaft attached to the gear case. A first bearing, a second bearing attached to the end cover and rotatably supporting a second shaft portion of the armature shaft, a second bearing disposed on an inner peripheral portion of the magnet, and a second bearing of the armature shaft; An armature core fixed to the shaft portion of the second shaft portion; a commutator fixed to the armature core on the second bearing side of the second shaft portion; and an electrically connectable outside of the commutator to the commutator. And a pair of brushes wound around the armature core and electrically connected to the commutator Armature coil, a counter gear rotatably supported by the gear case, meshed with the worm of the armature shaft, a wheel gear meshed with the counter gear, fixed to the wheel gear, and coupled to a load. An output shaft, and a first plate portion arranged on the second bearing side, and outside the commutator away from the first plate portion along the axial direction of the second shaft portion. A holder base mounted on the inside of the end cover and having a second plate portion that is disposed to support the brush and has a circuit breaker mounting portion; and a circuit of the second plate portion of the holder base. A motor with a speed reduction mechanism, comprising: a circuit breaker that is mounted on the breaker mounting portion so as to protrude toward the second bearing. 4. A first bearing insertion portion to be inserted into a first bearing is formed on the first shaft portion on the second shaft portion side of the first and second worms. The shaft portion has a second bearing insertion portion inserted into the second bearing on a side opposite to the first shaft portion, and an armature core mounting portion formed on the first shaft portion side. 4. The motor with a reduction mechanism according to claim 1, wherein a commutator mounting portion is formed on the mounting portion on the side of the second bearing insertion portion. 5. A pair of brush holding portions formed on the second plate portion of the holder base so as to be able to move each of the brushes toward the commutator and hold each of the brushes. A motor with a speed reduction mechanism according to item 1.