JP3499091B2 - Clock motor - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a timepiece motor.

[0002]

2. Description of the Related Art As a conventional timepiece motor, as shown in FIG. 2, a U-shaped stator a, a coil bobbin b fitted to one leg of the stator, and a drive wound around the coil bobbin. There is a coil c and a rotor d magnetically coupled to the magnetic pole portion of the stator. In this case, the stator a was formed to have a magnetic path having a cross-sectional area through which all the magnetic flux generated by the drive coil c can pass.

[0003]

The above-mentioned U-shaped stator is designed in a certain shape for the convenience of handling or from the viewpoint of automatic assembly, and the shape is still maintained. . However, recently, the magnetic characteristics of the magnetic material, which is the material of the stator, have been remarkably improved, and the battery life has also been improved. Therefore, for example, a battery used for a watch set to be driven at 1.3 V (Rated voltage 1.5V)
However, the initial voltage is usually about 1.6V. Moreover, the specifications of the drive coil are usually varied.

In the motor of the conventional timepiece using the stator having the fixed shape as described above, most of the magnetic flux generated by the drive coil c is designed to pass through the stator a, so that the initial voltage is as described above. Even when a large amount of magnetic flux is generated and a large amount of magnetic flux is generated due to variations in the specifications of the drive coil c, the magnetic flux passes through the stator a and contributes to the rotational drive of the rotor d. For this reason, an excessive driving force acts on the rotor d of the timepiece set to drive at 1.3 V as described above, which causes a problem that a loud noise is generated during rotation. It was In addition, since the battery voltage also varies and the specifications of the drive coil also vary, this variation causes a large variation in the force that acts to rotate the rotor d, and a stable motor cannot be obtained. there were.

[0005]

In order to solve the above problems SUMMARY OF THE INVENTION The feature of the present invention, a portion of the stator, so as to saturate a sufficient predetermined magnetic flux to work properly rotor
Ri Other small sectional area portion is formed tare of reduced cross-sectional area than the portion, even if an excessive magnetic flux caused by the small cross-sectional area portion
The rotor is where the driving force is given by a constant magnetic flux
In . As described above, the small cross-sectional area portion works so as to apply a constant driving force to the rotor without being affected by variations in battery voltage and driving coil specifications, and stable motor operation can be obtained.

[0006]

BEST MODE FOR CARRYING OUT THE INVENTION The present invention relates to a timepiece motor including a stator, a drive coil wound around a part of the stator, and a rotor which is magnetically coupled to a magnetic pole portion of the stator and is rotationally driven. In the above, a part of the stator is formed with a small cross-sectional area portion saturated with a predetermined magnetic flux sufficient to normally operate the rotor. It is preferable that the small cross-sectional area portion is formed at a position where the leakage magnetic flux generated in the small cross-sectional area portion does not affect the rotation of the rotor. The small cross-sectional area configured as described above is saturated with a predetermined magnetic flux even if an excessive magnetic flux is generated in the drive coil, so that the rotor is always given a driving force by a constant magnetic flux. , Perform stable and normal operation.

[0007]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Referring to FIG.
The coil bobbin 2 is fitted to the one leg piece 1a of the stator 1, and the drive coil 3 is wound around the coil bobbin. The pair of leg pieces 1a and 1b of the stator 1 have two magnetic pole portions 1 at the tips thereof, respectively.
c, 1d and 1e, 1f are formed. The rotor 4 magnetized to have two poles has four magnetic pole portions 1c, 1d and 1e,
It is located between 1f and is magnetically coupled.

A small cross-sectional area portion 11 is formed in a part of the stator 1 so that the rotor 4 is saturated with a predetermined magnetic flux sufficient for normal operation. As an example, 1.
In the case of a timepiece motor that normally operates at 3V, the cross-sectional area is made smaller than the other parts so that the motor is saturated with the magnetic flux generated in the drive coil 3 when the battery voltage is 1.3V. The position where the small cross-sectional area portion 11 is formed is formed at a position sufficiently separated from the rotor 4 so that the leakage magnetic flux generated in this small cross-sectional area portion does not affect the rotation of the rotor 4. That is, the small cross-sectional area portion 11 is formed on the opposite side of the drive coil 3 from the four magnetic pole portions 1a, 1b, 1c, 1d.

With such a structure, if a new battery is loaded and its initial voltage is 1.6 V, for example, a part of the magnetic flux generated in the drive coil 3 by this 1.6 V, that is, 1 Only the magnetic flux corresponding to 0.3 V saturates the small cross-sectional area portion 11. Then, this magnetic flux contributes to the driving force of the rotor 4, but the other magnetic flux becomes a leakage magnetic flux that does not affect the rotation of the rotor 4 and does not contribute to the driving force of the rotor 4. Even when a large amount of magnetic flux is generated due to variations in the specifications of the drive coil 3 in addition to the battery voltage, the existence of the small cross-sectional area portion 11 causes all the magnetic flux exceeding the predetermined magnetic flux to become a leakage magnetic flux, and the rotor 4 does not contribute to the driving force.

When the battery voltage drops to 1.3 V due to long-term use of the battery, the magnetic flux generated by the drive coil 3 saturates the small cross-section area 11 and the leakage magnetic flux does not occur, but the rotor 4 is driven. There is no change in the force, and the same driving force as at the initial stage acts on the rotor, so that stable driving is performed.
That is, as the driving force of the rotor 4, only a constant magnetic flux corresponding to 1.3V always acts, so that the rotor 4 always operates stably and normally.

The cross-sectional area of the small cross-sectional area portion 11 is set according to the electric equipment in which the motor is used, and an optimum motor for various equipment can be constructed only by changing the shape of part of the stator.

[0012]

As described above, according to the present invention, since a small cross-sectional area portion that is saturated with a predetermined magnetic flux sufficient to normally operate the rotor is formed in a part of the stator, variations in battery voltage and drive coil specifications are achieved. Even if an excessive magnetic flux is generated, the rotor is saturated with a predetermined magnetic flux and the driving force is always given to the rotor by this constant magnetic flux, so that a stable normal operation is performed. Since the small cross-section area is formed at a position where the leakage magnetic flux generated in the small cross-section area does not affect the rotation of the rotor, the rotor always operates more stably.

[Brief description of drawings]

FIG. 1 is a plan view showing an embodiment of the present invention.

FIG. 2 is a plan view showing a conventional example.

[Explanation of symbols]

1 stator 11 Small cross-section area of stator 3 drive coil 4 rotor

Claims (2)

(57) [Claims] 1. A motor of a timepiece comprising a stator, a drive coil wound around a part of the stator, and a rotor which is magnetically coupled to a magnetic pole portion of the stator and is rotationally driven. Some parts of the rotor are cut off more than other parts so that they are saturated with a predetermined magnetic flux sufficient to operate the rotor normally.
Thea is, excessive magnetic and small sectional area portion having a small area is formed
Even if a bundle is generated, the small cross-section area keeps the rotor at a certain magnetic
A timepiece motor characterized in that a driving force is given by a bundle . 2. A motor of a timepiece, wherein the small cross-sectional area portion is formed at a position where a leakage magnetic flux generated in the small cross-sectional area portion does not affect the rotation of the rotor.