TWI675531B - fan - Google Patents

Abstract

The fan system includes: an impeller; a motor unit, a rotating impeller; and a swinging mechanism for swinging the head in a direction that changes the direction of the motor; the swinging mechanism includes: a stator (6); a motor shaft (8); 6); and a stepping motor (3) having a rotor (7) provided with a gap between the motor shaft (8) and the motor shaft (8); the stepping motor (3) is a motor shaft ( 8) By the unbalanced magnetic attraction force caused by the offset from the center of the stator (6), while being stretched to the same side as the direction in which the rotor (7) is stretched, it is running at the speed at which the rotor (7) rotates.

Description

fan

The present invention relates to a fan equipped with a swing head mechanism using a stepping motor.

The stepping motor can freely change the rotation speed and rotation angle by the input pulse wave. Therefore, it is very useful to change the angle adjustment and rotation speed of the part. It is used in various fields to rotate the part.

In recent years, stepping motors have been used in the swinging motion of fans. The fan system includes an air-sending part that rotates an impeller mounted on a shaft body of a motor to generate wind. When the fan is used to supply air, it is required to swing the head to the left and right when it wants to send air to a wide range. When it is intended to stir the air in the room, it is required to swing the head to the top .

Patent Document 1 discloses a fan including a stepping motor for left and right swinging heads and a stepping motor for up and down swinging heads to realize angle adjustment of the left and right swinging heads and the up and down swinging heads.

[Patent Literature]

[Patent Document 1] Japanese Patent No. 5786440

The rotor of a stepping motor is due to the unbalance of its own weight, and the center of rotation is offset from the center of gravity. Therefore, the centrifugal force generated during rotation becomes the force that stretches the rotor in the radial direction. So stepping horse The rotor is usually driven along the outer periphery of the motor shaft included in the motor. The centrifugal force is generated in the direction from the center of rotation to the center of gravity. Therefore, the direction of the centrifugal force is changed in accordance with the rotation angle of the rotor.

However, when the motor shaft is offset from the center of the stator, the magnetic attraction generated by the stator becomes unbalanced in order to rotate the rotor, and the rotor is pulled in a specific direction. When the unbalanced magnetic attraction is stronger than the centrifugal force, when the centrifugal force acting on the rotating rotor and the unbalanced magnetic attraction force are directed in opposite directions, the rotor is stretched. At this time, the rotor system collides with the internal parts of the motor shaft or the stator, so a collision sound is generated after each rotation. Whether the rotor hits the motor shaft or whether it hits the stator depends on the gap between the rotor and the motor shaft and the gap between the rotor and the stator.

A fan that uses a stepping motor for swinging head movement. When the swinging head is running, the impact sound generated inside the stepping motor is amplified by the structure of the fan. Therefore, there is a problem that a user feels uncomfortable.

The present invention has been developed in view of the above-mentioned problems, and an object thereof is to obtain a fan for preventing noise from being generated from a stepping motor when the head is rotated.

In order to solve the above-mentioned problems and achieve the object, the present invention includes: an impeller; a motor unit that rotates the impeller; and a swing mechanism that performs a swing motion that changes the direction of the motor portion. The swing mechanism includes a stepping motor. The stepping motor includes a stator, a motor shaft provided inside the stator, and a rotor provided with a gap between the motor shaft and the motor shaft. The stepping motor is rotated at the speed of the rotor while it is being stretched to the same side as the direction in which the rotor is stretched by the unbalanced magnetic attraction generated by the motor shaft being offset from the center of the stator.

The fan of the present invention can be used to prevent noise generated by the stepping motor when the head is running. The effect of sound.

1‧‧‧ front shield

2‧‧‧ rear shield

3‧‧‧ Stepping Motor

3a‧‧‧Motor bracket

3b‧‧‧ underside

3c‧‧‧ Delivery agency

4‧‧‧Drive gear

5‧‧‧ rotating gear

6, 16‧‧‧ stator

7, 17‧‧‧ rotor

7a‧‧‧ Shaft

8, 18‧‧‧ Motor shaft

9‧‧‧grease

33‧‧‧Guard Ring

100‧‧‧fan

101‧‧‧ Impeller

102‧‧‧Motor Department

103‧‧‧ Pillar

104‧‧‧ base

104a‧‧‧Switch

105, 106‧‧‧ Head swing mechanism

Fig. 1 is a diagram showing the appearance of a fan according to a first embodiment of the present invention.

Fig. 2 is an exploded view of the front cover and the rear cover of the fan according to the first embodiment.

Fig. 3 is a diagram showing the internal structure of the base portion of the fan according to the first embodiment.

Fig. 4 is a perspective view of a stepping motor that realizes the left and right swinging mechanism of the fan of the first embodiment.

FIG. 5 is an exploded perspective view of a stepping motor that realizes the left and right swinging head mechanism of the fan of the first embodiment.

Fig. 6 is a diagram showing a state in which the stepping motor of the fan according to the first embodiment generates an unbalanced magnetic attraction force.

FIG. 7 is a diagram showing a state change during the rotation of a stepping motor that realizes the left and right swing mechanism of the fan of the first embodiment.

Hereinafter, the fan according to the embodiment of the present invention will be described in detail based on the drawings. The present invention is not limited to this embodiment.

First Embodiment

Fig. 1 is a diagram showing the appearance of a fan according to a first embodiment of the present invention. Fig. 2 is an exploded view of the front cover and the rear cover of the fan according to the first embodiment. Fig. 3 is a diagram showing the internal structure of the base portion of the fan according to the first embodiment. The fan 100 includes an impeller 101, a motor portion 102, a rotating impeller 101, a pillar portion 103 that supports the motor portion 102, and a base portion 104 that holds the pillar portion 103 at a root portion. The impeller 101 is mounted on a motor shaft of the motor unit 102. The electric motor of the electric motor unit 102 rotates the impeller 101, whereby The fan 100 generates wind. The fan 100 includes a front shield 1 and a rear shield 2 for protecting the impeller 101 so that a user cannot access the rotating impeller 101.

The rear cover 2 is attached to the motor portion 102. The impeller 101 is arranged inside the rear shroud 2. A guard ring 33 is mounted on the rear shield 2, and the front shield 1 is assembled to the guard ring 33, whereby the impeller 101 is covered and protected from the front and rear by the front shield 1 and the rear shield 2.

The motor unit 102 is provided with a swing mechanism 105 that drives up and down. In addition, the base portion 104 includes a swing mechanism 106 that is driven to the left and right by rotating the pillar portion 103. The head swing mechanism 105 in the up-down direction of the motor portion 102 and the head swing mechanism 106 in the left-right direction of the base portion 104 are combined, whereby the user can set the air blowing direction. The air volume of the fan 100 and the direction of the swing head are operated by a switch 104 a provided on the base portion 104. In addition, the air volume of the fan 100 and the direction of swinging the head can also be operated by the remote control.

A stepping motor 3 is provided inside the base portion 104. The stepping motor 3 rotates the internal gear to rotate the driving gear 4 mounted on the shaft. The pillar portion 103 is rotatably supported by the base portion 104. A rotation gear 5 is mounted on the lower portion of the pillar portion 103. When the driving gear 4 of the stepping motor 3 transmits a rotational force to the rotation gear 5, the pillar portion 103 rotates. In other words, the stepping motor 3 and the rotating gear 5 constitute the swinging mechanism 106 on the left and right of the fan 100. When the pillar portion 103 rotates, the swinging motion of the fan 100 is performed.

Fig. 4 is a perspective view of a stepping motor that realizes the left and right swinging mechanism of the fan of the first embodiment. FIG. 5 is an exploded perspective view of a stepping motor that realizes the left and right swinging head mechanism of the fan of the first embodiment. The stepping motor 3 is fixed to the motor shaft 8 perpendicularly to the bottom surface 3b of the motor holder 3a. A rotor 7 including a permanent magnet is provided on the surface of the cylindrical member, and a gap is provided between the rotor 7 and the motor shaft 8 to insert the motor shaft 8. The rotor 7 includes a shaft body 7 a serving as an output shaft of the stepping motor 3. The rotation of the shaft body 7a is transmitted to the drive gear 4 via the transmission mechanism 3c. After inserting the rotor 7 to the motor shaft 8 fixed to the motor bracket 3a In the state, the rotor 7 is rotated, so there is a gap between the inner diameter of the rotor 7 and the motor shaft 8. The rotor 7 is caused by the unbalance of its own weight, and rotates while generating centrifugal force to shake while rotating.

In addition, the motor shaft 8 may be offset from the center of the stator 6 to be fixed due to variations in manufacturing. When the motor shaft 8 is offset from the center of the stator 6, unevenness occurs in the gap between the outer periphery of the rotor 7 and the inner diameter of the stator 6. Fig. 6 is a diagram showing a state in which the stepping motor of the fan according to the first embodiment generates an unbalanced magnetic attraction force. As shown in FIG. 6, when an unbalanced magnetic attraction force is generated when the power is applied, a force in a specific direction is strongly applied to the rotor 7.

FIG. 7 is a diagram showing a state change during the rotation of a stepping motor that realizes the left and right swing mechanism of the fan of the first embodiment. The fan 100 of the first embodiment slows down the rotation speed of the rotor 7 to reduce the centrifugal force, so that the rotor 7 is not stretched by magnetic attraction. That is, the centrifugal force is made smaller and the magnetic attraction force exceeds the centrifugal force, so that the rotor 7 is rotated in a state where it is stretched to the same side as the direction in which it is stretched by the magnetic attraction force. The rotor 7 is rotated while being stretched in the same direction as the direction in which it is stretched by the magnetic attraction force. Therefore, the rotor 7 does not move rapidly and does not collide.

FIG. 7 shows changes in the rotation state of the rotor 17 when the difference in the matching force is small although the unbalanced magnetic attraction force is greater than the centrifugal force. When the rotor 17 rotates at a high speed, the rotor 17 rotates along the outer periphery of the motor shaft 18, and rotates in a state where a gap is ensured in a direction in which a centrifugal force acts. However, when the centrifugal force faces the opposite direction of the unbalanced magnetic attraction force, the centrifugal force becomes free of the components of the normal direction of the unbalanced magnetic attraction force. Therefore, the rotor 17 is stretched by the stator 16 and the rotor 17 is connected with the motor shaft 18 or said The parts inside the stepping motor of the stator 16 collide. The collision of the rotor 17 is a phenomenon that occurs when the centrifugal force is directed in the opposite direction of the unbalanced magnetic attraction force. Therefore, the collision of the rotor 17 is generated once every revolution.

The fan 100 of the first embodiment suppresses the rotation speed of the rotor 7 to about 70 rpm per minute, thereby reducing the centrifugal force generated on the rotor 7. The centrifugal force is defined by F = mrω ² , so when the rotor 7 and the rotor 17 have the same shape, the centrifugal force generated by rotating the rotor 7 at 70 rpm is about 0.56 times the centrifugal force generated by rotating the rotor 17 at 100 rpm Was reduced to more than half. Therefore, the rotation speed of the rotor 7 is preferably between 50 rpm and 100 rpm.

The impact sound generated by the impact of the rotor 17 is caused when the difference between the unbalanced magnetic attraction force and the centrifugal force is small. That is, although the unbalanced magnetic attraction is better than the centrifugal force, it is caused by the centrifugal force when the rotor 17 rotates along the outer periphery of the motor shaft 18 due to the centrifugal force. The centrifugal force generated on the rotor 7 of the stepping motor 3 of the fan 100 of the first embodiment is larger than half of the centrifugal force generated on the rotor 17. Therefore, the difference between the unbalanced magnetic attraction force and the centrifugal force makes the rotor 7 larger than the rotor 17. Therefore, by the centrifugal force, the rotor 7 does not rotate along the outer periphery of the motor shaft 8, and the rotor 7 is in a determined position. The balance magnetic force is continuously stretched while rotating. Therefore, the rapid movement of the rotor 7 during rotation can be avoided, and the generation of a collision sound caused by the collision of the rotor 7 can be suppressed.

As described above, the reason why the rotor 7 rotates is because a gap is provided between the rotor 7 and the motor shaft 8. By extremely reducing the gap between the rotor 7 and the motor shaft 8, the rapid movement of the rotor 7 can be suppressed. However, when the rotor 7 is a plastic molded product, the size of the rotor 7 varies greatly, and it is difficult to strictly manage the clearance system on the inner diameter side of the rotor 7. Here, the stepping motor 3 of the first embodiment has grease for filling the gap between the rotor 7 and the motor shaft 8 for the purpose of both reducing the impact noise of the rotor 7 and smoothing the rotation of the rotor 7. 9.

In addition, the cause of the centrifugal force in the rotor 7 is the imbalance of the dead weight of the rotor 7. When suppressing the imbalance of the weight of the rotor 7, it is necessary to improve the dimensional accuracy of the rotor 7. Although it is difficult to strictly manage the clearance system on the inner diameter side of the rotor 7, it is easier to manage the size of the outer diameter of the rotor 7. Therefore, the stepping motor 3 of the first embodiment has a smaller gap between the rotor 7 and the motor shaft 8 than between the stator 6 and the rotor 7. The gap. Therefore, the stepping motor 3 does not collide with the stator 6 even when the rotor 7 moves sharply. In addition, the internal variation of the stator 6 and the swing of the rotor 7 are also taken into consideration to determine the size of the gap between the stator 6 and the rotor 7, thereby improving the effect of reducing the collision sound caused by the collision of the rotor 7.

In the fan 100 of the first embodiment, the rotor 7 is rotated while being continuously stretched by the unbalanced magnetic attraction force. Therefore, the rapid movement of the rotor 7 during rotation can be avoided, and the impact of the collision sound caused by the collision of the rotor 7 can be suppressed. produce.

In the above description, the fan 100 suppresses the collision noise caused by the rotor 7 colliding on the stepping motor 3 which realizes the left-right swing mechanism 106. However, when the motor 100 is included in the up-down direction When the swinging head mechanism 105 is realized by a stepping motor, similarly to the stepping motor 3, the rotor can be rotated while being continuously stretched by an unbalanced magnetic attraction force, thereby suppressing the occurrence of a collision sound.

The structure shown in the above embodiment is an example of the content of the present invention, and may be combined with other well-known technologies, or a part of the structure may be omitted or changed without departing from the scope of the present invention.

Claims (5)

A fan includes: an impeller; a motor unit that rotates the impeller; and a swinging mechanism for swinging the head to change the direction of the motor. The swinging mechanism includes a stator and a motor shaft provided inside the stator. And a stepping motor having a rotor provided with a gap between the motor shaft and the motor shaft, the stepping motor being an unbalanced magnetic attraction force generated by the motor shaft due to a deviation from a center of the stator While being stretched to the same side as the direction in which the rotor is stretched, it is running at the speed at which the rotor rotates. The fan according to item 1 of the patent application scope, wherein the fan includes grease filled in a gap between the rotor and the motor shaft. The fan according to item 1 of the scope of patent application, wherein the gap between the rotor and the motor shaft is smaller than the gap between the stator and the rotor. The fan according to item 2 of the scope of patent application, wherein the gap between the rotor and the motor shaft is smaller than the gap between the stator and the rotor. The fan according to any one of claims 1 to 4, wherein the rotation speed of the aforementioned rotor is between 50 rpm and 100 rpm.