JP2001008407A - Drive motor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To facilitate drive control, at the same time, simplify the configuration for miniaturization, and improve reliability by actuating a brake device through centrifugal force being between the rotor shaft and the fixing case of an electric motor for driving a winding member. SOLUTION: When an electric motor 3 has a light load and rotary speed becomes excessive, an elastic thin plate piece 10-2 of a brake device 7 is displaced toward the outside in a radius direction from a position, in contact with the outer-periphery surface of a boss 8 due to a centrifugal force, and a permanent magnet piece 10-3 approaches a conductor part 10-4 via a small gap. Thus an eddy current is generated on the conductor 10-4, allowing the magnetic flux by the eddy current to act on the magnetic flux of the permanent magnet piece 10-3 for attracting the permanent magnet piece 10-3 to the conductor part 10-4, applying damping force to the electric motor 3, and preventing excessive rotation. When the electric motor 3 is rotated normally, the elastic thin plate piece 10-2 is placed onto the outer-periphery surface of the boss 8, thus preventing brake operation from being generated.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a driving motor, and more particularly to a driving motor for driving a sheet member winding device such as a winding type blind or shutter.

[0002]

2. Description of the Related Art FIG. 7 shows a conventional drive motor, 1 is a cylindrical sheet winding member serving as a winding core when winding a sheet such as a blind or a shutter, and 2 is this cylindrical sheet winding member. 1 is a fixed cylindrical housing which slidably supports the winding member 1 and 3 is a cylindrical housing 2
The squirrel-cage induction motor disposed in the motor 3-1 is the motor 3
And a reduction gear 4 composed of a planetary gear mechanism inserted between the rotor shaft 3-1 and the cylindrical housing 2.
-1 is an output shaft of the speed reduction mechanism 4;
And an external attachment member 6 for fixedly supporting the motor 3 and a connecting member 6 for connecting the output shaft 4-1 and the cylindrical sheet winding member 1 to each other.

[0003]

As described above, in the conventional drive motor, it is essential to provide a brake device for suppressing overspeed rotation of the motor at a light load, but it is difficult to control the drive easily. In addition, there has been an issue of miniaturization and improvement of reliability by simplifying the configuration.

[0004]

A drive motor according to the present invention comprises:
It is characterized by comprising an electric motor for driving the winding member, and a brake device which operates by the action of centrifugal force inserted between the rotor shaft of the electric motor and the fixed housing.

[0005] The brake device is an eddy current brake device, and includes a conductor member fixed to the housing and a displacement portion integrally held on the rotor shaft and capable of being displaced radially outward by centrifugal force. And a permanent magnet member fixed to the displacement portion so as to face the conductor member via a gap.

The brake device is an eddy current brake device, and includes a permanent magnet member fixed to the housing,
A displacement portion integrally held on the rotor shaft and capable of being displaced radially outward by centrifugal force, and a conductor member fixed to the displacement portion so as to face the permanent magnet member via a gap. Have.

[0007] The displacement portion is made of an elastic thin plate, and is displaced radially outward by centrifugal force when the rotor shaft reaches an excessive rotation speed.

The brake device has a support plate that supports the displacement portion and is fixed perpendicularly to the rotor shaft. When the displacement portion is displaced radially outward by centrifugal force, the support plate is provided. Form a surface that supports the end surface of the permanent magnet.

The brake device has a support plate that supports the displacement portion and is fixed perpendicular to the rotor shaft. When the displacement portion is displaced radially outward by centrifugal force, the support plate is provided. Form a surface that supports the end surface of the conductor member.

The brake device is an eddy current brake device, and includes a conductor member fixed to the housing and an outer periphery thereof which is restrained in the rotating direction by the rotor shaft and is movably held in the axial direction. A movable portion having a permanent magnet member, and means for moving the movable portion in the axial direction by centrifugal force. When the movable portion is moved in the axial direction, the permanent magnet and the conductor portion are connected via a minute gap. And the opposing area changes.

[0011] The brake device is an eddy current brake device, and includes a permanent magnet fixed to the housing and an outer periphery which is constrained by the rotor shaft in the rotational direction and is movably held in the axial direction. A movable part having a conductor member, and means for moving the movable part in the axial direction by centrifugal force, and when the movable part is moved in the axial direction, the permanent magnet and the conductor part are separated through a minute gap. They face each other, and the facing area changes.

The means for moving the movable portion in the axial direction comprises a link mechanism connecting the movable portion and the rotor shaft, and a weight connected to a contact portion of the link mechanism. When the weight moves radially outward due to centrifugal force, the movable part is moved in the axial direction via the link mechanism.

[0013]

Embodiments of the present invention will be described below with reference to the drawings.

FIG. 1 shows the drive motor of the present invention in a state where the eddy current braking device is not operating. FIG. 2 shows the drive motor in a state where the brake is applied.

In the present invention, a brake device 7 is provided between the rotor shaft 3-1 and the cylindrical housing 2 as shown in FIG.

The brake device 7 is provided with the rotor shaft 3-
1, a frustoconical boss 8 having a central portion fixed to the motor 3 so that its large diameter side is the motor 3 side, and a support circle fixed vertically between the boss 8 and the motor 3 to the rotor shaft 3-1. It consists of a plate 9 and a brake part 10 held by this support disk 9. The brake portion 10 is fixed to a side surface of the support disk 9 on the boss 8 side, and the disk portion 10-1 shown in FIGS.
A plurality of, for example, six plate-shaped elastic thin pieces 10-2 bent at an acute angle of 90 ° or more inward from the outer periphery of 0-1 toward the boss 8 side, and fixed to the outer surface of each elastic thin piece 10-2. And a cylindrical conductor portion 10-4 fixed to the inner peripheral surface of the cylindrical housing 2 at a position facing the permanent magnet piece 10-3.

Since the drive motor of the present invention has the above-described configuration, the speed reduction mechanism 4 is driven by driving the motor 3.
And the sheet winding member 1 is rotated via the connecting member 6 and
We come to take up sheet.

If the motor 3 is lightly loaded and the rotation speed becomes excessive, the centrifugal force causes the brake device 7 to rotate.
1 is displaced radially outward from the position where the elastic thin plate piece 10-2 is in contact with the outer peripheral surface of the boss 8 as shown in FIG. The conductor portion 10-4 is in a state of approaching through the minute gap.

As a result, an eddy current is generated in the conductor portion 10-4, and a magnetic flux due to the eddy current is generated by the permanent magnet 1
Acting on the magnetic flux from 0-3, the permanent magnet piece 10-3 is attracted to the conductor portion 10-4, and a braking force is applied to the electric motor 3, so that excessive rotation is prevented.

When the motor 3 is rotating normally, FIG.
As shown in the figure, the elastic thin plate piece 10-2 is placed on the outer peripheral surface of the boss 8 so that the braking action does not occur, and the elastic thin plate piece 10-2 and the permanent magnet piece 1
Derivation of vibration and noise during rotation of 0-3 can be prevented.

When the rotational speed of the electric motor 3 becomes excessive and the elastic thin plate piece 10-2 is displaced radially outward due to centrifugal force, the end face of the permanent magnet 10-3 is brought into contact with the support disk 9. The elastic thin plate 10-
2 is prevented from being excessively displaced.

FIG. 5 shows another embodiment of the present invention in which an auxiliary member 10-5 is inserted between the outer peripheral surface of the elastic thin plate piece 10-2 and the permanent magnet piece 10-3. According to this, the mass of the portion where the centrifugal force acts is reduced by the auxiliary member 10-.
5 can be adjusted to obtain a predetermined braking force.

FIG. 6 shows still another embodiment of the present invention. In this embodiment, the brake device 7 is mounted on the rotor shaft 3-1 via a spline (not shown).
-1, a holding member 11 attached so as to be slidable in the axial direction but integrally rotated in the rotation direction, a permanent magnet piece 10-3 attached to the outer periphery of the holding member 11, A link mechanism 12 for moving the shaft 11 in the axial direction of the rotor shaft 3-1 and a cylindrical conductor portion 10-4 fixed to the inner peripheral surface of the cylindrical housing 2; Have their free ends rotatably connected to the weight 13 and their base ends formed by links 12-1 and 12-2 connected to the rotor shaft 3-1 and the holding member 11, respectively. If the rotation speed of the electric motor 3 becomes excessive,
Due to the centrifugal force, the weight 13 moves radially outward,
As a result, the permanent magnet piece 10 is
-3 is opposed to the conductor portion 10-4 via a minute gap, and the facing area is increased or decreased according to the axial movement amount.

The operation and effect of this embodiment are substantially the same as those of the above embodiments.

[0025]

The mounting positions of the permanent magnet piece 10-3 and the conductor portion 10-4 may be reversed, but an eddy current is generated in the conductor portion 10-4, and a large amount of heat is generated. Therefore, considering the heat radiation effect, the conductor portion 10-4
Is preferably provided in the cylindrical housing 2.

[Brief description of the drawings]

FIG. 1 is an explanatory view showing a state in which a brake device of a drive motor according to the present invention is not operating.

FIG. 2 is an explanatory diagram showing a state in which the brake device of the example in FIG. 1 is operating.

FIG. 3 is a front view of a main part of a brake device used for the drive motor of the present invention.

FIG. 4 is a sectional view of a main part of the brake device of FIG. 3;

FIG. 5 is an explanatory view showing a state in which a brake device of another embodiment of the drive motor of the present invention is operating.

FIG. 6 is an explanatory view of still another embodiment of the drive motor of the present invention.

FIG. 7 is an explanatory diagram of a conventional drive motor.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Sheet winding member 2 Cylindrical housing 3 Induction motor 3-1 Rotor shaft 4 Reduction mechanism 4-1 Output shaft 5 External mounting member 6 Connecting member 7 Brake device 8 Boss 9 Support disk 10 Brake part 10-1 Circle Plate part 10-2 Elastic thin plate piece 10-3 Permanent magnet piece 10-4 Conductor part 10-5 Auxiliary member 11 Holding member 12 Link mechanism 13 Weight

Claims (12)

[Claims] 1. A drive motor comprising: an electric motor for driving a winding member; and a brake device which operates by the action of centrifugal force inserted between a rotor shaft of the electric motor and a fixed housing. 2. The brake device according to claim 1, wherein the brake device is an eddy current brake device, and the brake device is held integrally with the conductor member fixed to the housing and the rotor shaft, and can be displaced radially outward by centrifugal force. The drive motor according to claim 1, further comprising: a displacement portion; and a permanent magnet member fixed to the displacement portion so as to face the conductor member via a gap. 3. The brake device is an eddy current brake device, and is integrally held by a permanent magnet member fixed to the housing and the rotor shaft, and can be displaced radially outward by centrifugal force. The drive motor according to claim 1, further comprising: a displacing portion; and a conductor member fixed to the displacing portion so as to face the permanent magnet member via a gap. 4. The drive motor according to claim 2, wherein the displacement portion is made of an elastic thin plate, and is displaced radially outward by centrifugal force when the rotor shaft is at an excessive rotation speed. 5. The drive motor according to claim 2, wherein an auxiliary member is interposed between said displacement portion and said permanent magnet member. 6. The drive motor according to claim 3, wherein an auxiliary member is interposed between the displacement portion and the conductor member. 7. The rotor shaft supports the displacement portion,
The boss having a truncated conical shape is provided.
The drive motor as described. 8. The brake device has a support plate that supports the displacement portion and is fixed perpendicular to the rotor axis,
6. The drive motor according to claim 2, wherein when the displacement portion is displaced radially outward by centrifugal force, the support plate forms a surface that supports an end surface of the permanent magnet. 9. The brake device has a support plate that supports the displacement portion and is fixed perpendicular to the rotor axis,
7. The drive motor according to claim 3, wherein when the displacement portion is displaced radially outward by centrifugal force, the support plate forms a surface that supports an end surface of the conductor member. 10. The brake device is an eddy current brake device, wherein the conductor member is fixed to the housing, and is held by the rotor shaft in a rotational direction and held movably in an axial direction. A movable portion having a permanent magnet member on its outer periphery,
Means for moving the movable portion in the axial direction by centrifugal force. When the movable portion is moved in the axial direction, the permanent magnet and the conductor portion face each other via a minute gap, and the facing area changes. The drive motor according to claim 1. 11. The brake device is an eddy current brake device, wherein the permanent magnet fixed to the housing is held by the rotor shaft in a rotational direction and held movably in an axial direction. A movable part having a conductor member on its outer periphery; and a means for moving the movable part in the axial direction by centrifugal force. The permanent magnet and the conductor part are minute when the movable part is moved in the axial direction. Opposed through a gap,
The drive motor according to claim 1, wherein the facing area changes. 12. The means for moving the movable part in the axial direction comprises a link mechanism connecting the movable part and the rotor shaft, and a weight connected to a contact part of the link mechanism. 12. The drive motor according to claim 9, wherein when the weight moves radially outward due to centrifugal force, the movable portion moves in the axial direction via the link mechanism.