JP6617226B2 - Rotor magnetizing method for hybrid stepping motor - Google Patents

Description

  The present invention relates to a rotor magnetizing method of a hybrid type stepping motor, and in particular, the magnetic poles of a total of three ring magnets provided on a ring rotor core of a motor after assembly are arranged so that the same poles face each other from the outside of the motor. It relates to a new improvement for magnetizing.

A number of documents have been disclosed as this type of hybrid type stepping motor that has been used in the past, and examples thereof include the configurations of Patent Documents 1, 2, and 3.
That is, in FIG. 2 of a rotating electric machine (not shown) of Patent Document 1, a permanent magnet is sandwiched between a pair of rotor yokes, and a casing is disposed close to each rotor yoke.
Moreover, in FIG. 2 of the stepping motor of patent document 2, a permanent magnet is only clamped between a pair of rotor yokes.
Moreover, in FIG. 1 of the hybrid type stepping motor of patent document 3, it is equivalent to the structure of the above-mentioned patent document 1. FIG.
FIG. 4 shows a cross-sectional perspective view of a configuration actually used in the above-described hybrid stepping motor.
That is, a ring-shaped stator 3 having a stator winding 2 is provided on an inner wall 1a of a casing 1 having a box shape in FIG. 4, and a rotor provided on a rotating shaft 4 is provided inside the ring-shaped stator 3. 5 is rotatably arranged.

  A hybrid stepping motor 10 is provided on the outer periphery 5 a of the rotor 5 by providing a pair of first and second annular rotor cores 6, 7 and a first annular magnet 8 sandwiched between the annular rotor cores 6, 7. Is configured.

JP 2012-244736 A Japanese Patent Laid-Open No. 9-298867 JP 2005-245162 A

Since the conventional hybrid stepping motor is configured as described above, the following problems exist.
As described above, in the case of a hybrid stepping motor in which only one conventional ring magnet is mounted on a rotor, the motor is put in a magnetizing yoke and magnetized with an external magnetic field by a large current from a magnetizing power source. There is no problem with the magnetization itself, but it has not been able to meet the demand for small size and large torque.

Therefore, development of a small and large torque type hybrid stepping motor (shown in FIG. 1 of the present invention) as a three-piece configuration in which the number of ring magnets provided on the rotor is increased is being advanced by the present applicant. .
However, it is extremely difficult to use a rotor with three ring magnets and make the magnetic poles S and N face each other, but the conventional magnetization procedure is as follows. .
A Assembling the motor (not magnetized)
B Put the motor in the magnetizing yoke, and magnetize with an external magnetic field by a large current from the magnetizing power source.
In this case, the three magnets are magnetized in the same direction by the external magnetic field, and the magnetic poles are not in the same polarity and opposed to each other. In order to manufacture a motor of a rotor arranged oppositely by a conventional method, first prepare a rotor unit with one magnet sandwiched between them, prepare two separate magnets, and follow the procedure shown by C to F below. It will be produced. That is,
C Magnetize the rotor (one magnet).
D Magnetize the other two magnets one by one.
E Adhere the magnet to the rotor.
F Assemble the rotor into the motor.
When this means is used, there are few problems if it is a prototype, but if it is a mass production method, the risk of quality deterioration is inevitable because dust such as iron powder attracted by the magnet enters the motor.
Accordingly, it has been impossible to avoid quality deterioration due to contamination (dust inclusion) in the method of installing the rotor inside the stator after being magnetized alone and an increase in manufacturing cost due to an increase in manufacturing procedures.

  The present invention has been made to solve the above-described problems, and in particular, three ring magnets are mounted on the rotor core, the hybrid stepping motor after motor assembly is magnetized, and the magnetic poles of the magnets are It is an object of the present invention to provide a rotor magnetizing method for a hybrid stepping motor configured to be opposed to each other with the same polarity.

  A hybrid stepping motor according to the present invention includes a rotor rotatably provided between a pair of bearings provided in a casing having an annular stator, first and second annular rotor cores provided on an outer periphery of the rotor, A first annular magnet provided between the annular rotor cores, and second and third annular magnets that are provided on the outer surface of each annular rotor core and are made of magnets having a lower magnetic holding force than the first annular magnet, After the first, second, and third annular magnets are stacked and assembled via the respective annular rotor cores, and using a hybrid stepping motor that forms one unmagnetized motor, the hybrid A first step of putting a mold stepping motor in a magnetizing yoke and magnetizing in a first direction from the outside of the casing; In the magnetic yoke, the hybrid stepping motor is replaced so that the end surface of the casing is opposite to that in the first step, and the second step is performed to magnetize in the second direction opposite to the first direction. And each magnetic pole of each ring-shaped magnet is arranged to face each other with the same polarity via each ring-shaped rotor core, and the magnetization in the second direction is a plurality of times. The first ring magnet is a neodymium magnet, and the second and third ring magnets are samarium cobalt magnets.

Since the method for magnetizing a hybrid stepping motor according to the present invention is configured as described above, the following effects can be obtained.
That is, a rotor provided rotatably between a pair of bearings provided in a casing having a ring-shaped stator, first and second ring-shaped rotor cores provided on the outer periphery of the rotor, and each ring-shaped rotor core. The first ring-shaped magnet, and the second and third ring-shaped magnets that are provided on the outer surface of each of the ring-shaped rotor cores and have a lower magnetic holding force than the first ring-shaped magnet, and the first, second, After the third annular magnet is laminated and assembled through the annular rotor cores, and using a hybrid stepping motor that forms a single unmagnetized motor, the hybrid stepping motor is used as a magnetizing yoke. A first step of magnetizing in the first direction from outside the casing, and then in the magnetizing yoke, the hybrid type step The ping motor is replaced so that the end face of the casing is opposite to that in the first step, and the second step is performed to magnetize in the second direction opposite to the first direction. The magnetic poles of the magnet are disposed opposite to each other with the same polarity through the respective ring-shaped rotor cores, so that dust such as iron powder does not adhere to the conventional rotor core, so that high quality is maintained, It can be mass-produced at low cost.
Further, since the magnetization in the second direction is performed a plurality of times, more reliable magnetization can be achieved.
Further, the first annular magnet is made of a neodymium magnet, and the second and third annular magnets are made of a samarium cobalt magnet, whereby a small and powerful magnetic force can be obtained.

It is sectional drawing of the principal part of the hybrid type stepping motor used for the magnetization method of the hybrid type stepping motor by this invention. It is explanatory drawing which shows the state which performs the 1st magnetization to the motor of FIG. It is explanatory drawing which shows the state which performs the 2nd magnetization after the 1st magnetization of FIG. It is a cross-sectional perspective view showing a conventional hybrid type stepping motor.

  The method of magnetizing a hybrid stepping motor according to the present invention magnetizes the magnetic poles of a total of three ring-shaped magnets provided on the ring-shaped rotor core of the assembled motor so as to be opposed to each other with the same polarity from the outside of the motor. is there.

A preferred embodiment of a rotor magnetizing method for a hybrid stepping motor according to the present invention will be described below with reference to the drawings.
In addition, the same code | symbol is attached | subjected and demonstrated to a part the same as that of a prior art example, or an equivalent part.
In FIG. 1, what is indicated by reference numeral 10 is a hybrid type stepping motor, and the hybrid type stepping motor 10 has a box shape as a whole and is provided with a casing having a pair of bearings 4a and 4b. A rotary shaft 4 having a rotor 5 is rotatably provided in each of the bearings 4a and 4b, and first and second annular rotor cores 6 and 7 are attached to the outer periphery 5a of the rotor 5 in a state of being separated from each other. Yes.

  Between the ring-shaped rotor cores 6 and 7, a first ring-shaped magnet 8 made of a neodymium magnet having a high magnetic holding force is sandwiched, and the outer surfaces 6a and 7a of the ring-shaped rotor cores 6 and 7 are provided. Second and third annular magnets 9 and 11 made of samarium cobalt magnet having a magnetic holding force lower than that of the first annular magnet 8 are attached.

A case where the ring-shaped magnets 8, 9, 11 of the hybrid stepping motor 10 configured as described above are magnetized will be described.
First, after the assembly shown in FIG. 1 is completed, an unmagnetized hybrid stepping motor 10 is loaded into a magnetized yoke (not shown), and the first direction which is the normal direction as shown in FIG. In A, the first magnetization is performed.
In the state shown in FIG. 2 immediately after the first magnetization is completed, the magnetic poles N and S of the ring magnets 8, 9, and 11 are magnetized so as not to face each other.

Next, the hybrid stepping motor 10 in the state where the first magnetization in the first direction A is completed (FIG. 2) is reversed in the magnetizing yoke (not shown) (that is, the casing 1 is rotated 180 degrees). 3), as shown in FIG. 3, the second magnetization in the second direction B is performed with a charge larger than the magnetization in the case of FIG.
Due to the second magnetization described above, the magnetic poles N and S of the ring-shaped magnets 8, 9 and 11 are arranged opposite to each other via the ring-shaped rotor cores 6 and 7 (SN, NS, SN, as shown in FIG. 3). In this case, for example, when the magnetizing process is not performed with a degree of demagnetization, the second direction B is magnetized again as described above.
Therefore, as described above, since the magnet 10 is magnetized even by using the assembled motor 10 in the non-magnetized state, the ring-shaped magnets 8, 9, 11 are not touched by hand at all. No contamination problems have occurred.

The gist of the present invention is as follows.
That is, a rotor 5 rotatably provided between a pair of bearings 4a and 4b provided in a casing 1 having an annular stator 3, and first and second annular rotor cores 6 provided on an outer periphery 5a of the rotor 5. 7, a first ring magnet 8 provided between the ring-shaped rotor cores 6 and 7, and a magnetic holding force weaker than the first ring-shaped magnet 8 provided on the outer surfaces 6 a and 7 a of the ring-shaped rotor cores 6 and 7. Second and third annular magnets 9 and 11 made of magnets, and the first, second and third annular magnets 8, 9 and 11 are laminated and assembled via the respective annular rotor cores 6 and 7. After that, the hybrid stepping motor 10 that forms one unmagnetized motor is used, and the hybrid stepping motor 10 is placed in a magnetized yoke to form the casing. The first step of magnetizing from the outside in the first direction A, and then the hybrid stepping motor 10 in the magnetizing yoke is opposite to the end step 1b of the casing 1 in the first step. And the second step of magnetizing in the second direction B opposite to the first direction A, the magnetic poles N, S of the ring magnets 8, 9, 11 It is a method in which the respective rotor cores 6 and 7 are opposed to each other with the same polarity, the magnetization in the second direction B is a plurality of times, and the first annular magnet 8 is The second and third ring magnets 9 and 11 are made of neodymium magnets, and are made of samarium cobalt magnets.

  According to the magnetizing method of the hybrid type stepping motor according to the present invention, since the magnet is magnetized from the outside of the hybrid type stepping motor having three ring magnets on the rotor, a highly reliable motor free from contamination during assembly is obtained. be able to.

DESCRIPTION OF SYMBOLS 1 Casing 1a Inner wall 1b End surface 2 Stator winding 3 Ring-shaped stator 4a, 4b Bearing 5 Rotor 5a Outer periphery 6, 7 1st, 2nd ring-shaped rotor core 6a, 7a Outer surface 8, 9, 11 1st, 2nd, 3rd ring-shaped magnet 10 Hybrid stepping motor

Claims (3)

A rotor (5) provided rotatably between a pair of bearings (4a, 4b) provided in a casing (1) having a ring-shaped stator (3), and an outer periphery (5a) of the rotor (5). The first and second annular rotor cores (6, 7), the first annular magnet (8) provided between the annular rotor cores (6, 7), and the outer surfaces of the annular rotor cores (6, 7) ( 6a, 7a) and second and third ring magnets (9, 11) made of magnets having a magnetic holding power weaker than that of the first ring magnet (8). The first, second, second A hybrid stepping motor (three-ring magnets (8, 9, 11)) stacked and assembled via the respective ring-shaped rotor cores (6, 7) and forming a single unmagnetized motor ( 10)
A first step in which the hybrid stepping motor (10) is put in a magnetizing yoke and magnetized in the first direction (A) from the outside of the casing (1);
Next, in the magnetized yoke, the hybrid stepping motor (10) is replaced so that the end surface (1b) of the casing (1) is opposite to that in the first step, and the first direction ( A second step of magnetizing in the second direction (B) opposite to A),
Each of the magnetic poles (N, S) of the ring magnets (8, 9, 11) is disposed opposite to each other with the same polarity via the ring rotor cores (6, 7). Magnetization method.   2. The method for magnetizing a hybrid stepping motor according to claim 1, wherein the magnetization in the second direction (B) is performed a plurality of times.   The hybrid stepping according to claim 1 or 2, wherein the first annular magnet (8) comprises a neodymium magnet, and the second and third annular magnets (9, 11) comprise a samarium cobalt magnet. Magnetization method of the motor.

Images