JP2561557Y2 - Small motor - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Technical Field of the Invention] The present invention relates to a small motor having a reduction gear mechanism, in which a motor drive unit such as a rotor, a stator and a coil set and a driven unit such as a reduction gear train and an output shaft are used. The present invention relates to an improvement of a flat type small motor arranged side by side.

[Conventional technology]

Conventionally, in a small motor having a reduction gear mechanism,
A driven portion such as a reduction gear train and an output shaft is provided above a motor driving portion such as a rotor, a stator, and a coil set in a direction axially above the rotor axis.

In the small-sized motor having the above configuration, since the thickness dimension in the rotor axis direction is large, the motor drive section and the driven section are arranged side by side in a plane, and a reduction gear train is provided from the rotor in a direction perpendicular to the rotor axis. A flat, small-sized motor has been proposed. The small-sized motor has a small thickness in the axial direction of the rotor, and is therefore thin.

[Problems to be solved by the invention]

In the above-described thin small motor with a reduction gear mechanism, the plane area of the motor is large because the respective component parts constituting the motor are arranged in a plane.

By the way, devices and devices in which these motors are incorporated are being made more compact, and in order to make the mounting area of the motor smaller, even in a small motor with a thin reduction gear mechanism, the thickness dimension in the rotor axis direction is reduced. There is a need to make the plane area of the motor smaller without changing it.

For this purpose, it is only necessary to reduce the size of each component constituting the motor. For example, it is conceivable to reduce the size of a coil set including a coil bobbin and a coil winding. In such a coil set, the coil bobbin is formed of an insulating member, and is formed integrally with a hollow cylindrical winding drum portion and both ends of the winding drum portion, and protrudes radially outward from the winding drum portion. It consists of a flange part. Then, an electric wire is wound around a winding space formed between the outer periphery of the winding drum portion and between the two flange portions to form an exciting coil winding.

At this time, the coil winding is electrically insulated from other members by the winding drum portion and both flange portions. Approach radially, resulting in imperfect electrical insulation, which has a significant impact on safety. Also, at this time, if the outer diameter of the coil winding is to be reduced, the winding must be made thinner, so that the temperature rise of the coil winding during motor operation increases, and a predetermined motor performance cannot be obtained.

[Purpose of the invention]

Therefore, an object of the present invention is to enable downsizing of a motor without deteriorating motor safety and motor performance.

[Solution of the invention]

In view of the above, the present invention provides a cut-out portion by cutting out a part of the outer peripheral end of the flange portion of the coil bobbin, and positioning the gear made of an insulating material in the reduction gear train at the cut-out portion, thereby forming a coil winding and other portions. While maintaining insulation with the member (a gear made of an insulating material), predetermined motor performance, in particular, the field force of the coil winding is maintained.

[Structure of device]

1 and 2 show the structure of the small motor 1 of the present invention.

The small motor 1 includes a lower case-shared stator substrate and a lid-side case 3 combined with an upper surface thereof.
, A coil bobbin 4, a coil winding 5, a stator substrate 6, a rotor 7, and a reduction gear train 8 are provided.

The stator substrates 2 and 6 are both formed of a magnetic plate, and are fixed in a state where they are joined together with the coil bobbin 4 interposed therebetween. As a result, the stator substrate 6 is located at an intermediate position between the case substrate 3 and the case 3. The coil bobbin 4 is made of an insulator such as plastic, and has a hollow cylindrical winding drum 9 and disk-shaped flanges 10a and 10b integrally formed at both ends of the winding drum 9, respectively. And their flanges 10
a, the outer surfaces of 10b contact the stator substrates 2, 6, respectively,
They are coalescing.

The coil winding 5 is wound around the outer periphery of the winding drum section 9 and is formed integrally with the terminal block 11 formed integrally with the flange section 10a.
The terminal 12 protrudes outside from the terminal cover 13 via the terminal 12.

The stator substrates 2 and 6 are aligned with the surfaces of the flange portions 10a and 10b, and have a plurality of comb-shaped pole teeth 14 in a bent state along the center ring. These pole teeth 14 are annularly arranged on the inner periphery of the winding drum 9 and face the outer periphery of the rotor 7.

The rotor 7 is composed of a circular permanent magnet 16 and a rotor gear portion 17 at the center thereof, and a rotor shaft fixed between the case substrate 2 and the case 3 serving as a case.
15 is rotatably supported. The permanent magnets 16 are magnetized on the outer peripheral surface so as to have alternately different polarities, and correspond to the pole teeth 14 while forming a gap.

The rotation of the rotor 7 is transmitted to the gear 22 of the output shaft 23 via the rotor gear 17, the reverse rotation preventing gear 18, and the reduction gear train 8 via the compound (two-stage) type gears 19, 20, 21. Is transmitted. These gears 18, 19, 20, 21 are rotatably supported by gear shafts 24, 25, 26, 27 provided between the stator substrate 2 or the stator substrate 6 and the case 3.

Here, the gears 19 and 20 in the reduction gear train 8 are both compound gears (two-stage gears), are thin in the axial direction, and are disposed between the case 3 and the stator substrate 6. Also,
The remaining gears 21 and 22 in the reduction gear train 8 are thickened in the axial direction by an insulating member, and are disposed between the stator substrate 2 and the case 3 which also serve as a case.

The gear 18 for preventing reverse rotation is provided as necessary when regulating the rotation direction of the rotor 7, holds the one-way rotation regulating lever 28 rotatably at the boss portion, and frictionally couples at the gear side surface. I have. The tip of the one-way rotation restricting lever 28 corresponds to a protrusion 29 formed on the rotor gear portion 17.

The output shaft 23 is integrated with the output-side gear 22 by press-fitting or the like, and the radial bearing 30 of the stator substrate 2 and the radial bearing of the case 3 are also used.
It is rotatably supported by 31. The load in the thrust direction of the output shaft 23 is supported by an electric device to be incorporated, for example, a machine frame of a microwave oven.

In the present invention, of the two disk-shaped flange portions 10a and 10b of the coil bobbin 4, a part of the outer peripheral end of at least one of the flange portions 10a is cut out by, for example, two straight lines for each of the gears 21 and 22. At the position of the cut-out portion 32, axially thick gears 21 and 22 of the reduction gear train 8 located near the cut-out portion 32 are arranged. gear
Reference numeral 21 denotes a small tooth portion, which penetrates and is located at the position of one cutout 32, and a large tooth portion includes a flange portion 10a and a gear 22.
And at a certain interval. Also, the gear 22
The tooth tip portion intrudes and is located at the position of the other cutout 32.

In this embodiment, since the stator substrate 6 also interferes with the tooth tips of the gears 21 and 22, the stator substrate 6 is cut off slightly deeper than the cut portion 32 of the flange portion 10a as a substrate cut portion 33. In this way, even if the coil winding 5 is loosened, a necessary insulation distance between the coil winding 5 and the stator substrate 2 can be secured.

[Action of the invention]

In the above configuration, the gear 21 of the reduction gear train 8,
When the intrusion 22 enters the cutout portion 32 and is present there, the length of the gear 8 along the meshing direction can be shortened by that much, so that the small motor 1 can be made smaller as a whole.

When a rotating magnetic field is generated by the coil winding 5,
The rotor 7 is excited by it and rotates in either direction. If the rotation of the rotor 7 is in the opposite direction, the rotation causes the tip of the one-way rotation restricting lever 28 to protrude.
At that point, the rotor 7
Is corrected to the rotation in the normal rotation direction by receiving the rotation force in the normal rotation direction. The rotation of the rotor 7 is transmitted to the output shaft 23 by the reduction gear train 8, that is, the gears 19, 20, 21, 22, and transmitted to the driven member as a rotational motion.

[Other embodiments of the invention]

In another embodiment of FIG. 4, a cutout portion 32 is formed at a part of the outer peripheral end of the flange portion 10a in correspondence with the gear 22 of the reduction gear train 8, but a part of the stator substrate 6 is moved away from the gear 22. This is an example in which an insulation distance is ensured and the two do not interfere with each other by being bent.

In each of the above embodiments, one of the flange portions 10a
Is formed only in the cut portion 32,
May be formed in the same manner for the flange portion 10b on the side of the stator substrate 2 which also serves as the case.
Are formed as cutout holes in the stator substrate 2 which also serves as the case. In addition, the cut portion 32 may not be formed in a straight line, but may be formed as a concentric arc in relation to the gears 21 and 22 that avoid interference.

[Effect of the invention]

In the present invention, at least the flange portion of the bobbin is cut out in the radial direction at the outer peripheral portion to form a cutout portion, and a gear made of an insulating material of the reduction gear train is located at this cutout portion, so that the reduction gear train is provided. The distance in the meshing direction can be shortened, the motor can be downsized accordingly, and no solution such as cutting out a part of the magnetic poles is adopted. The size can be reduced in terms of the length in the direction and the thickness in the axial direction.

[Brief description of the drawings]

FIG. 1 is a plan view of a small motor with a lid-side case removed, FIG. 2 is a cross-sectional view of a gear train of the small motor taken along a meshing direction (AA line in FIG. 1), and FIG. The figure is a cross-sectional view along a main part (the line BB in FIG. 1), and FIG. 4 is a cross-sectional view of the main part of another embodiment. 1 ... small motor, 2 ... stator board also used as case,
3 ... case, 4 ... coil bobbin, 5 ... coil winding, 6 ... stator substrate, 7 ... rotor, 8 ... reduction gear train, 9 ... winding drum section, 10a, 10b ... flange section, 14……
Pole teeth, 16 ... permanent magnets, 18, 19, 20, 21, 22 ... gears,
32: Cutout section, 33: Board cutout section.

Claims (1)

(57) [Scope of request for utility model registration] A hollow cylindrical winding drum (9) made of an insulating member and disk-shaped flanges (10a, 10b) integrally formed at both ends of the winding drum (9), respectively. A coil bobbin (4) made of an insulator, a coil winding (5) wound around the outer periphery of the winding body (9), and a group of comb-shaped pole teeth (14) formed in an annular shape. And this pole tooth (1
4) The flange portions (10, 10) from both ends of the coil bobbin (4) so that the group is arranged on the inner periphery of the winding drum portion (9).
The stator substrates (2, 6) respectively bonded to 10b)
And a rotor (7) having a permanent magnet (16) included in the pole teeth (14) group and magnetized so that the outer periphery is alternately of a different polarity.
And an axially thin gear (19, 20) that transmits the rotation of the rotor (7) to the output shaft (23) while reducing the speed, and a gear (21, 22) formed of an axially thick insulating member. A reduction gear train (8) and two cases (2) for housing the above-described coil bobbin (4), coil winding (5), stator substrate (6), rotor (7) and reduction gear train (8) in an internal space. And (3), wherein the stator substrate (6) and the stator substrate (6) are provided.
One flange portion (10a) attached to the two cases (2, 3) is arranged so as to be located in the axial middle of the two cases (2, 3),
The thin gears (19, 20) in the reduction gear train (8) are arranged in a space formed by the stator substrate (6) and the one case (3), and further, the one flange portion ( A part of the outer peripheral end of 10a) is cut to form a cut part (32), and the insulating member is thickened in the axial direction at the position of the cut part (32) between the two cases (2, 3). A small motor (1) characterized in that gears (21, 22) comprising: