JPH11289734A - Compact vibration motor and its manufacture - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain vibration only by an armature core by winding the armature coil around two magnetic body salient poles of an eccentric armature core, connecting a commutator to the terminal of the armature coil, and providing a pair of brushes that slide on the commutator. SOLUTION: An eccentric armature core 3 is composed of magnetic body salient electrodes 3a and 3b and a non-magnetic body salient electrode 4, armature coils 51 and 52 are wound around the salient electrodes 3a and 3b consisting of a magnetic body via a coating layer in the eccentric armature core 3, and a flat-plate-shaped commutator 6 consisting of a printed wiring board is wired to the terminal of the armature coils 51 and 52, thus constituting an eccentric rotor R1. Then, by allowing a pair of brushes 8 being provided at a bracket 7 to slide on the flat-plate-shaped commutator 6 at an open angle, power is supplied to the armature coils 51 and 52, thus reducing the eccentricity weight of the outside and obtaining sliding only by the eccentric armature core 3.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a small vibration motor used as a silent call means of a mobile communication device, and in particular, to a small vibration motor having an eccentric armature iron core which does not require an eccentric weight and a method of manufacturing the same. About.

[0002]

2. Description of the Related Art Conventionally, as shown in FIG. 10, an eccentric weight W made of a tungsten alloy is arranged on an output shaft S of a cylindrical coreless DC motor M as a silent call means for a pager, a portable telephone or the like. There is known an apparatus that generates vibration using a difference in centrifugal force of W.

However, in the case where the eccentric weight W is added to the conventional output shaft S, there is a design limitation such that the turning space of the eccentric weight W must be taken into consideration on a device such as a pager. However, there is a problem in cost because an expensive tungsten alloy is used.

For this reason, the present applicant has previously disclosed a cylindrical coreless type vibration motor in which the output shaft is eliminated and the built-in rotor is eccentric, as disclosed in Japanese Patent Application No. 2-309070 (US Pat.
No. 155).

[0005] Since the motor has no output shaft and no eccentric weight, it has been well received in the market because it is not subject to design restrictions, is easy to use, and has no danger during turning. Due to the cylindrical coreless winding type, the problem that the number of processing steps increases is included.

[0006] In order to vibrate the rotor itself with an iron core type replacing the cylindrical coreless winding type, the applicant of the present invention disclosed in Japanese Patent Application No. 2-294482, one of the three salient pole type iron cores. It proposes one with the poles removed.

However, the above-mentioned two salient pole type iron core type is suitable for a motor having a relatively large output with a large output such as a massager, but it is a portable device using a low voltage such as a pager. Is not suitable because the center of gravity moves little and the amount of vibration is small.

Further, the present applicant has previously disclosed USP-53410
As disclosed in Japanese Patent No. 57, an eccentric armature core formed by facing a rotor in which three salient poles made of a magnetic material are all biased to one side on a four-pole field magnet magnetized by NS alternately. We propose a small vibration motor equipped with it. Furthermore, there is one disclosed in Japanese Patent Application Laid-Open No. 9-261918 as a disclosure of a similar technical idea. However, in such a motor, since the armature core made of a magnetic material is biased to one side, the cogging torque (the force attracted to the field magnet)
However, the air gap must be relatively large, and the diameter of the motor itself cannot be reduced.

[0009]

As a structure for preventing cogging torque as described above, if the salient poles of the three-phase magnetic material are replaced by two salient poles, one of which is missing, the magnetic field attracts to the field magnet. The cogging torque can be prevented to some extent because the forces are offset. However, since the two pole salient pole type shifts the center of gravity more slightly than the structure, the difference in centrifugal force during rotation is small, and the amount of vibration generated to the outside is small. In addition, since the salient poles are unequal, if the shaft is directly pressed into the center hole of the iron core to make it a long and thin armature core, the pressure applied to the shaft increases as the core thickness increases. Is large and the shaft is easy to bend. Further, since the armature core is made of a hard silicon steel plate, the shaft is easily damaged, which causes a problem in sliding performance. Particularly, in recent ultra-thin cylindrical motors, the shaft diameter has to be reduced to 0.8 mm or less, so this problem has been greatly highlighted. In order to prevent the bending of the shaft, there is a means for dispersing the stress by changing the mutual positions of the salient poles of the core little by little, but this cannot be done unless the salient poles are of equal division type.

A first object of the present invention is to eliminate a two salient pole type defect by eliminating an external eccentric weight and making it possible to obtain vibration only with an armature core, and to move the center of gravity. While reducing the cogging torque and thus enabling sufficient starting at low voltage. A second object of the present invention is to prevent the bending of the shaft without changing the mutual positions of the salient poles so that a fixed shaft type can be adopted in spite of the deformed salient pole type core. A third object of the present invention is to provide a structure capable of easily winding an armature coil while having an eccentric armature core in which all salient poles are biased to one side, and a method of manufacturing the same.

[0011]

According to the first aspect of the present invention, there is provided a field magnet comprising a plurality of magnetic poles, a housing storing the field magnet, Two magnetic salient poles receiving the magnetic flux of the field magnet and a non-magnetic salient pole arranged between the two salient poles so as to hold the magnetic salient pole and at least the blade portion are made non-magnetic. An eccentric armature core biased to one side, a shaft supporting the eccentric armature core, an armature coil wound around at least two magnetic salient poles of the armature core, and the armature coil This can be achieved by providing a commutator to which the terminal is connected and a pair of brushes slidingly contacting the commutator.

[0012] As a specific means for solving the problem, a second aspect is described.
The non-magnetic salient pole can be achieved by a metal body as in the invention described in (1).

Another specific means for solving the problem is that the nonmagnetic salient pole contains a highly slidable resin having a density (specific gravity) of 5 or more as in the invention as set forth in claim 3. Can be achieved. Still other specific problem solving means include:
The eccentric armature core may be rotatably supported by the non-magnetic salient pole itself on a shaft fixed to the housing. Further, it is preferable that an armature coil is wound around the non-magnetic material salient pole to make this part a coreless type. Further, in these means for solving the problems, it is preferable that at least the blade portion of the nonmagnetic salient pole is arranged by utilizing the space around the armature coil as in the invention as set forth in claim 6. Good.

[0014] As another means for achieving the above object, a seventh aspect is provided.
A field magnet consisting of a plurality of magnetic poles as in the invention shown in
A housing containing the field magnet; two magnetic salient poles receiving the magnetic flux of the field magnet; a nonmagnetic salient pole disposed between the two salient poles and having at least a blade portion made non-magnetic; Eccentric armature core biased to one side, a shaft supporting the eccentric armature core, an armature coil wound around at least two magnetic salient poles of the armature core, After manufacturing a small-sized vibration motor having a pair of brushes that are in sliding contact with the commutator to which the terminals of the coil are connected, after winding the armature coil around the at least two magnetic salient poles, This can be achieved by assembling the two magnetic salient poles with the non-magnetic salient poles to adopt an eccentric armature core.

According to the first aspect of the present invention, the cogging torque is canceled out by the two substantially magnetic salient poles which are opposed to each other and is reduced, and the center of gravity is reduced by the salient poles made of the non-magnetic material. Can move a large distance. According to the means for achieving the object, a relatively heavy metal body such as a copper plate is used, so that the centrifugal force can be increased at the time of rotation, and if the shaft is pressed into the copper plate, it will be damaged. There is no fear. Further, the metal body may be an oil-impregnated bearing having a copper-based porous material. According to the means for achieving the object set forth in claim 3, since a non-magnetic high-slidability resin is included, the salient pole itself can be used as a bearing.
This eliminates the need to press-fit the shaft, thereby preventing bending of the shaft. According to the fourth aspect of the present invention, since the motor can be a fixed shaft type, there is an advantage that the structure is simplified. According to the problem solving means described in claim 5,
It can contribute to torque increase while reducing generation of cogging torque. According to the means for achieving the object set forth in claim 6,
Since the weight of the blade portion is large and the amount of eccentricity is large, large vibration is obtained, and the motor itself can be downsized. According to the means for achieving the object described in claim 7, a large winding slot can be obtained, and aligned winding can be performed.

[0016]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The configuration of the present invention will be described below based on embodiments shown in the drawings. FIG. 1 is a cross-sectional view of a main part of a small vibration motor according to a first embodiment of the present invention.
FIG. 3 is a sectional view of an essential part inside the motor, FIG. 3 is an explanatory view of the operation principle of the first embodiment, and FIG. 4 is a transverse sectional view of the essential part showing a second embodiment of the motor of the present invention. 5 is an explanatory view of the operation principle of the second embodiment, FIG. 6 is a cross-sectional view of a principal part showing a third embodiment of the motor, and FIG. 7 is an explanatory view of the operation principle of the third embodiment. FIG. 8 is a cross-sectional view of a principal part showing a third embodiment of the motor, and FIG. 9 is an assembly view for explaining an embodiment of a method of manufacturing the motor of the present invention.

In FIG. 1, reference numeral 1 denotes a ring-shaped field magnet made of a rare earth plastic, which is alternately magnetized into N and S equally into four poles. Reference numeral 2 denotes a casing made of a tin-plated steel plate that holds the field magnet 1 and serves as a magnetic path. Reference numeral 3 denotes an eccentric armature core showing the characteristics of the present invention, in which three salient poles on one side among six equally salient poles made of a magnetic material such as a silicon steel plate are deleted, and the center of the remaining three salient poles is further removed. And an anchor-type non-magnetic salient pole 4 made of an oil-impregnated bearing having a copper-based porous material is disposed here. That is, the magnetic salient poles 3a, 3
The eccentric armature core 3 is constituted by b and the nonmagnetic salient poles 4. The pivot of the non-magnetic salient pole 4 is a hinge. A bearing hole 4a is formed in the hinge, and the above-mentioned magnetic salient poles 3a and 3b are pressed and held outside the bearing hole 4a. Here, each blade a, b at the tip of the magnetic salient poles 3a, 3b
Is set to be full of the magnetic poles of the field magnet 1 and neutral (non-magnetized portion) for efficiency. The eccentric armature core 3 is further provided with armature coils 51 and 52 wound around salient poles 3a and 3b made of a magnetic material via a coating layer (not shown), as shown in FIG. As will be described later, the terminal is connected to a predetermined terminal of the flat plate commutator 6 formed of a printed wiring board to constitute an eccentric rotor R1. Here, the blade 4b of the nonmagnetic salient pole 4 is provided with the armature coil 51, in order to increase the weight of the nonmagnetic salient pole itself.
The front magnetic body salient poles 3a, 3a, 3
A part is superimposed on each blade a, b at the tip of b.
Although not specifically shown, if cost permits,
Another such non-magnetic material salient pole 4 may be prepared and arranged facing the space where the lower armature coils 51 and 52 are wound. By doing so, the bearing portion can be raised and lowered, so that bearing loss is reduced.

A motor using such an eccentric armature core 3 is, as can be seen from FIGS.
And a rotatably mounted shaft J fixed to a bracket 7 constituting a housing H via a bearing hole 4a of a salient pole 4 made of the non-magnetic material also serving as a bearing. Of the armature coil 51, 8
52 is supplied with electric power. The plate commutator 6 has commutator pieces 6a, 6b, 6c, 6d, 6e and 6f divided into six equal parts as shown in FIG. 3 to be described later, and between the opposing commutator pieces 6a-6d, Electrode patterns 66a, 66b shorting 6b-6e and 6c-6f
And 66c are formed by printing, and the armature coil 51,
The winding start terminal of 52 is connected to the commutator pieces 6b and 5d, and the winding end terminal is connected to the commutator pieces 6c and 6c, respectively, to form a star connection system.

Next, the principle of rotation of the first embodiment will be described with reference to FIG. Now, when a DC voltage is applied to the pair of positive and negative brush pieces 8, 8 by a required power supply (not shown), first, an eccentric electric machine including armature coils 51, 52, magnetic material salient poles 3a, 3b, and commutator 6. The child core 3 is shown in FIG.
At the position, the armature coil flows in the direction of the arrow,
The salient poles 3a and 3b are magnetized to N and S, respectively.
Is attracted to the S1 pole of the field magnet and repelled from the N1 pole, generating torque in the direction of arrow A. Salient pole 3b is S
Since it is magnetized to the poles, it is attracted to the N2 pole of the field magnet and repelled from the S1 pole, so that a torque is also generated in the direction of arrow A. As the rotation advances, the same figure b (60 °)
, The armature coil 5 of the salient pole 3a is de-energized, and the opposite S pole of the N pole of the salient pole 3b is generated and repelled from the S1 pole of the field magnet. Even if rotation stops at this position, start-up becomes easy. When the rotation further proceeds and reaches the position c (90 °), current flows in the opposite direction, but the position of the field magnet is also reversed, and torque is generated in the direction of arrow A to rotate. No counter torque which hinders rotation occurs at other positions. Therefore, as long as power is supplied, the power is switched cyclically and the rotation is continued. Although not shown, it is a matter of course that the delta connection type armature coil may be formed by changing the position of the brush with respect to the field magnet. . Needless to say, the shape and width of the blade of each salient pole are considered to be the best in design.

In the above description, the number of salient poles is three, and the number of magnetic poles of the field magnet is four. However, the present invention is not limited to this. It is also possible to increase or decrease the number of poles.

FIG. 4 shows a second embodiment of the motor according to the present invention. That is, reference numeral 11 denotes a ring-shaped field magnet made of a rare earth plastic, which is magnetized alternately with N and S equally into six poles. I have. Reference numeral 2 denotes a casing made of a tin-plated steel plate that holds the field magnet 11 and serves as a magnetic path. Reference numeral 33 denotes an eccentric armature core exhibiting the characteristics of the present invention, and has an opening angle of 150 degrees to 18 degrees.
It is composed of two magnetic salient poles 33a and 33b made of a silicon steel plate arranged opposite to each other in a range of 0 degree, and a non-magnetic salient pole 44 arranged between the two salient poles. . The magnetic salient poles 33a and 33b make the blades aa and bb open larger than the field poles, and the open angle as a whole is within 4 poles + N (N is a non-magnetized portion) of the magnet when viewed from a plane. The non-magnetic salient pole 44 is made of a highly slidable resin having a density (specific gravity) of 5 and also serves as a bearing. The non-magnetic salient pole 44 has a hinge shape. A bearing hole 44a is formed in the hinge, and the above-mentioned magnetic salient poles 33a and 33b are pressed and held outside the bearing hole 44a. As shown in FIG. 5, the eccentric armature core 33 further has armature coils 53 and 54 wound around magnetic salient poles 33a and 33b via a coating layer (not shown). Here, the blade 44 of the nonmagnetic salient pole 44
The air-core armature coil 45 is fitted in b, and this portion is of a coreless type. These terminals are divided into nine equally divided commutator pieces 66a, 66b, 66c, 66d, 66.
e, 66f, 66g, 66h and 66i are connected to predetermined commutator pieces of the commutator 66. That is, the winding start terminals of the armature coils 53 and 54 and the air-core armature coil 45 are connected to the commutator pieces 66a, 66e and 66c, and the winding end terminals are collectively connected including the air-core armature coil 45, thereby forming a star connection system. Further, on the commutator 66, electrode patterns Pa, Pb and Pc for short-circuiting every two commutator pieces are formed by printing to constitute an eccentric rotor R2. The pair of brushes 88 are in sliding contact with the commutator 66 at an open angle (180 degrees in this case) which is an odd multiple of the field pole. Here, the structure of the motor is the same as that of the first embodiment, and the description thereof is omitted.

Next, the principle of rotation of the second embodiment will be described with reference to FIG. Now, a pair of positive and negative brush pieces 88, 88
When a DC voltage is applied from a required power source (not shown) to the armature coils, first, the armature coils 53 and 54, the magnetic material salient poles 33a,
FIG. 5A shows an eccentric rotor R2 composed of the eccentric rotor 33b and the commutator 66.
At the position (0 °), the armature coil flows in the direction of the arrow, and the salient poles 33a and 33b are magnetized to N and S, respectively. The salient pole 33a is attracted to the S1 pole of the field magnet and the N1 pole. It is more repelled and generates torque in the direction of arrow A. Since the salient pole 33b is magnetized to the S pole, the N of the field magnet is
Since it is attracted to the two poles and repelled from the S1 pole, torque is also generated in the direction of arrow A. When the rotation advances and reaches the position (30 °) in FIG. 3B, the armature coil 5 of the salient pole 33b is de-energized, and the S
Since the N pole opposite to the pole is generated and repelled from the N3 pole of the field magnet, even if the rotation is stopped at this position, the starting becomes easy. No counter torque which hinders rotation occurs at other positions. As the rotation further advances, the position (60
In the case of に), current flows in the opposite direction, but the position of the field magnet is also reversed, and torque is generated in the direction of arrow A to rotate. No counter torque which hinders rotation occurs at other positions. Here, the air-core armature coil 45 of the nonmagnetic salient pole 44 is also energized, and a torque is also generated in the direction of the arrow A in accordance with Fleming's left-hand rule, so that stronger rotation is obtained. . Therefore, as long as power is supplied, the power is switched cyclically and the rotation is continued. Also, the above description has been made with the star connection type, but by changing the position of the brush, etc.,
Delta connection can also be used.

FIG. 6 shows a third embodiment of the same motor of the present invention. More specifically, 111 and 112 are ferrite crescent-shaped field magnets which are magnetized to N and S poles and It is held facing each other. Reference numeral 333 denotes an eccentric armature core exhibiting the features of the present invention, and has an open angle of 10 as a whole.
It is composed of two magnetic salient poles 333a and 333b made of a silicon steel plate arranged opposite to each other in a range of 0 to 150 degrees, and a non-magnetic salient pole 444 arranged between the two salient poles. Have been. The magnetic salient poles 333a and 333b are blade a
aa and bbb are formed as large as possible. Here, the nonmagnetic salient pole 444 is formed of a high specific gravity resin containing tungsten grains having a density (specific gravity) of 12. The main part of the nonmagnetic salient pole 444 has a hinge shape, and an oil-impregnated bearing 444a is fitted therein. The magnetic salient poles 333a and 333b are held by being press-fitted to the outside thereof. As shown in FIG. 7, the eccentric armature core 333 further includes armature coils 55, 56 via magnetic coatings (not shown) on salient magnetic poles 333a, 333b.
Are wound to constitute the eccentric rotor R3. This eccentric rotor R3 further includes a commutator 666, as shown in FIG.
Are commutator pieces 666a, 666b divided into three equal parts,
And 666c, the winding start terminals of the armature coils 55 and 56 are connected to the commutator pieces 666a and 666b, and the winding end terminals are connected together and connected to the 666c, thereby forming a star connection system. Since the configuration as a motor is generally known, a description thereof will be omitted.

Next, the principle of rotation of the third embodiment will be described with reference to FIG. Now, a pair of positive and negative brush pieces 888, 8
When a DC voltage is applied to 88 by a required power supply (not shown), first, armature coils 55 and 56 and magnetic material salient pole 333 are applied.
eccentric rotor R comprising a, 333b and commutator 666
3 flows into the armature coils 55 and 56 in the direction of the arrow at the position shown in FIG.
b is magnetized to N and S, respectively, and the salient pole 333a is attracted to the S pole of the field magnet and the salient pole 333b is magnetized to the S pole. Generates torque.゜ The rotation proceeds, and FIG.
In the case of ゜), the armature coil 55 of the salient pole 333a is de-energized, but an N pole opposite to the S pole of the salient pole 333b generated by energization is generated and attracted from the S pole of the field magnet, so that torque is generated. Will be. Therefore, even if rotation stops at this position, start-up becomes easy. When the rotation further advances to the position shown in FIG. C (90 °), the salient pole 3
The armature coil 55a is energized and repulsed from the S pole of the field magnet to generate torque in the direction of arrow A and rotate. Therefore, as long as power is supplied, the power is switched cyclically and the rotation is continued.

FIG. 8 shows a motor according to a fourth embodiment of the present invention. That is, the nonmagnetic salient pole 45 is made of a relatively soft copper plate having a large specific gravity, and the shaft JJ is made of a magnetic salient pole 3a.
This is a so-called shaft-rotation type which is fixed by being pressed into this copper plate together with 3b. In this case, the shaft can be made a part of a magnetic path by using magnetic stainless steel. Further, an iron-based bearing is required on the housing side. Of course, it goes without saying that a bearing can be mounted on the copper plate 45 to make the shaft fixed.

As shown in FIG. 9, the method of manufacturing a small vibration motor according to the present invention is characterized in that the magnetic salient poles 3a, 33a, 333a and 3b, 33b,
After winding the armature coils 5 and 5 around 33b, the process of assembling the nonmagnetic salient poles 4, 44 and 444 was adopted.
Since winding can be easily performed and the slot can be formed larger than the winding width, aligned winding can be performed. The present invention is not limited to the above embodiments, but various embodiments can be adopted without departing from the spirit of the present invention.

[0027]

Since the small vibration motor according to the present invention is constructed as described above, the following effects can be obtained. According to the first aspect of the present invention, the cogging torque is offset by the two magnetic poles that are substantially opposed to each other, so that the starting is facilitated. Can be large. According to the invention as set forth in claim 2, since a relatively heavy metal body such as a copper plate is used, the centrifugal force can be increased at the time of rotation, and if the shaft is pressed into the copper plate, there is a risk of being damaged. Absent. Further, since the metal body can be an oil-impregnated bearing having a copper-based porous material, it is not necessary to provide a special bearing. According to the third aspect of the present invention, since the non-magnetic salient pole is made to contain a highly slidable resin, the salient pole itself can be used as a bearing, which is advantageous in cost. According to the fourth aspect of the present invention, since the motor can be a fixed shaft type, the structure is simplified, the number of parts is reduced, and there is an advantage that the cost is advantageous.
According to the invention as set forth in claim 5, it is possible to contribute to an increase in torque while reducing the occurrence of cogging torque. Claim 6
According to the invention described in (1), the weight of the plate portion becomes large and the amount of eccentricity becomes large, so that large vibration can be obtained and the motor itself can be reduced in size. According to the seventh aspect of the invention, a large winding slot can be obtained, and aligned winding can be performed.

[Brief description of the drawings]

FIG. 1 is a cross-sectional view of a main part of a small vibration motor according to a first embodiment of the present invention.

FIG. 2 is a side view of main parts inside the motor.

FIG. 3 is an explanatory diagram of an operation principle of the first embodiment.

FIG. 4 is a main part transverse sectional view showing a second embodiment of the motor of the present invention.

FIG. 5 is an explanatory view of the operation principle of the second embodiment.

FIG. 6 is a main part transverse sectional view showing a third embodiment of the motor of the present invention.

FIG. 7 is an explanatory view of the operation principle of the third embodiment.

FIG. 8 is a cross-sectional view of a main part showing a fourth embodiment of the motor of the present invention.

FIG. 9 is an assembly view for explaining an embodiment of the method for manufacturing the motor of the present invention.

FIG. 10 is a perspective view of a conventional small vibration motor.

[Explanation of symbols]

1, 11, 111 Field magnet 2 Casing 3 Eccentric armature core 3a, 33a, 333a 3b, 33b, 333b Magnetic salient poles 4, 44, 444, 45 Non-magnetic salient poles 51, 52, 53, 54 Armature Coil 6, 66, 666 Commutator 7 Bracket 8, 88, 888 Brush J, JJ Shaft H Housing

[Procedure amendment]

[Submission date] July 7, 1998

[Procedure amendment 1]

[Document name to be amended] Statement

[Correction target item name] Claims

[Correction method] Change

[Correction contents]

[Claims]

7. A field magnet consisting of a plurality of magnetic poles, a housing containing the field magnet, two magnetic salient poles receiving magnetic flux of the field magnet, and a space between the two salient poles. An eccentric armature core having at least one non-magnetic material salient pole having a non-magnetic blade portion disposed non-magnetic; a shaft supporting the eccentric armature core;
In manufacturing a small vibration motor having an armature coil wound around the magnetic salient poles, a commutator to which the terminal of the armature coil is connected, and a pair of brushes slidingly contacting the commutator. A method of manufacturing a small vibration motor having an eccentric armature core by winding an armature coil around at least two magnetic salient poles and then attaching non-magnetic salient poles to the two magnetic salient poles . ────────────────────────────────────────────────── ───

[Procedure amendment]

[Submission date] December 16, 1998

[Procedure amendment 1]

[Document name to be amended] Statement

[Correction target item name] 0018

[Correction method] Change

[Correction contents]

A motor using such an eccentric armature core 3 is, as can be seen from FIGS.
And a rotatably mounted shaft J fixed to a bracket 7 constituting a housing H via a bearing hole 4a of a salient pole 4 made of the non-magnetic material also serving as a bearing. Of the armature coil 51, 8
52 is supplied with electric power. The plate commutator 6 has commutator pieces 6a, 6b, 6c, 6d, 6e and 6f divided into six equal parts as shown in FIG. 3 to be described later, and between the opposing commutator pieces 6a-6d, An electrode pattern for short-circuiting 6b-6e and 6c-6f is printed and formed. The winding start terminals of the armature coils 51 and 52 are connected to commutator pieces 6b and 5d, and the winding end terminals are collectively connected to 6b.
c, respectively, to form a star connection system.

[Procedure amendment 2]

[Document name to be amended] Statement

[Correction target item name] 0019

[Correction method] Change

[Correction contents]

Next, the principle of rotation of the first embodiment will be described with reference to FIG. Now, when a DC voltage is applied to the pair of positive and negative brush pieces 8, 8 by a required power supply (not shown), first, an eccentric electric machine including armature coils 51, 52, magnetic material salient poles 3a, 3b, and commutator 6. The child core 3 is shown in FIG.
At the position, the armature coil flows in the direction of the arrow,
The salient poles 3a and 3b are magnetized to N and S, respectively.
Is attracted to the S1 pole of the field magnet and repelled from the N1 pole, generating torque in the direction of arrow A. Salient pole 3b is S
Since it is magnetized to the poles, it is attracted to the N2 pole of the field magnet and repelled from the S1 pole, so that a torque is also generated in the direction of arrow A. As the rotation advances, the same figure b (60 °)
, The armature coil 51 of the salient pole 3a is de-energized, and the opposite S pole of the N pole of the salient pole 3b is generated and repelled from the S1 pole of the field magnet. Even if the rotation stops, the starting becomes easy. When the rotation further proceeds and reaches the position c (90 °), current flows in the opposite direction, but the position of the field magnet is also reversed, and torque is generated in the direction of arrow A to rotate. No counter torque which hinders rotation occurs at other positions. Therefore, as long as power is supplied, the power is switched cyclically and the rotation is continued. Although not shown, it is a matter of course that the delta connection type armature coil may be formed by changing the position of the brush with respect to the field magnet. . Needless to say, the shape and width of the blade of each salient pole are considered to be the best in design.

[Procedure amendment 3]

[Document name to be amended] Drawing

[Correction target item name] Figure 3

[Correction method] Change

[Correction contents]

FIG. 3

Claims (7)

[Claims] 1. A field magnet comprising a plurality of magnetic poles, a housing in which the field magnet is stored, two magnetic salient poles receiving magnetic flux of the field magnet, and a space between the two salient poles. An eccentric armature core that is arranged so as to hold this magnetic salient pole and biases at least one side of a non-magnetic salient pole in which at least the blade portion is non-magnetic, and a shaft that supports this eccentric armature core, A small armature coil having an armature coil wound around at least two magnetic salient poles of the armature core, a commutator to which terminals of the armature coil are connected, and a pair of brushes slidingly contacting the commutator; Vibration motor. 2. The small vibration motor according to claim 1, wherein the nonmagnetic salient pole is a metal body. 3. The small vibration motor according to claim 2, wherein the nonmagnetic salient pole contains a highly slidable resin having a density (specific gravity) of 5 or more. 4. The small vibration motor according to claim 2, wherein the eccentric armature core is rotatably supported by the nonmagnetic salient pole itself on a shaft fixed to the housing. 5. The small vibration motor according to claim 1, wherein an armature coil is wound around the nonmagnetic salient pole to make this portion a coreless type. 6. The small vibration motor according to claim 1, wherein at least the blade portion of the non-magnetic salient pole is arranged using a space around which an armature coil is wound. 7. A field magnet consisting of a plurality of magnetic poles, a housing containing the field magnet, two magnetic salient poles receiving magnetic flux of the field magnet, and a space between the two salient poles. An eccentric armature core having at least one non-magnetic material salient pole having a non-magnetic blade portion disposed non-magnetic; a shaft supporting the eccentric armature core;
In manufacturing a small vibration motor having an armature coil wound around the magnetic salient poles, a commutator to which the terminal of the armature coil is connected, and a pair of brushes slidingly contacting the commutator. A method of manufacturing a small vibration motor having an eccentric armature core by winding an armature coil around at least two magnetic salient poles and then attaching non-magnetic salient poles to the two magnetic salient poles .