JP3495227B2 - Radial gap type vibration motor with eccentric non-magnetic core - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a radial air gap type vibration motor having an eccentric non-magnetic core which is suitable for use as a silent notification source for small radio communication devices (pagers, mobile phones).

[0002]

2. Description of the Related Art Small wireless communication devices (pagers,
As a vibration motor used for a silent notification source of a mobile phone), an eccentric weight W made of a tungsten alloy is arranged on a rotary output shaft S of a small cylindrical DC motor M as shown in FIG. It is known that vibration is obtained by utilizing the generated centrifugal force.

[0003]

However, in the case where the eccentric weight is added to the output shaft, the set maker has to consider the turning space of the eccentric weight, and the eccentric weight during rotation. Since the weight is exposed, it is dangerous, and if the eccentric weight is directly impacted by dropping or the like, the shaft may be deformed.

Therefore, the applicant of the present invention has previously proposed a cylindrical coreless type vibration motor in which the output shaft is eliminated and the built-in rotor itself is eccentric.
No. 155), and in the flat type motor, the eccentric weight is eliminated so that the rotor itself is eccentric so as to obtain vibration during rotation. Japanese Patent Application No. 63-11868 (US Pat. No. 5,033,623).
No. 9) is proposed.

Further, in order to vibrate the rotor itself by the iron core type instead of the coreless winding type, the present applicant has previously filed Japanese Patent Application No. 4-286987 (US Pat. No. 5,410,057).
As shown in FIG. 3, all three salient pole type iron cores are proposed to be biased to one side (within 180 degrees). A device having such a structure may have a relatively high starting voltage, but since it has cogging torque, further improvement is expected.

[0006] The object of the present invention is the above-mentioned Japanese Patent Application No. 4-28.
By further improving 6987 (US Pat. No. 5,341,057), it is possible to reduce the starting voltage by eliminating the cogging torque while increasing the moving amount of the center of gravity for generating the centrifugal force, and to make the cored type. Therefore, it is an object of the present invention to provide a radial air gap type vibration motor including an eccentric non-magnetic core which is advantageous in terms of cost.

[0007]

The above problems can be solved by adopting a means for eliminating the cogging torque while increasing the moving amount of the center of gravity for generating the centrifugal force. In this way, starting can be facilitated and vibration can be increased.

[0008]

DETAILED DESCRIPTION OF THE INVENTION As the one embodiment of the invention shown in claim 1, and a housing comprising a case and end bracket, generates a magnetic field placed on radial part of the housing A magnet having a plurality of magnetic poles alternately magnetized N and S, and fixed to the case so as to face the magnet through a radial gap.
Rotatably housed in the housing via a shaft
Includes a semi-cup-shaped eccentric rotor cut away on one side, the
The eccentric rotor is an eccentric non-magnetic core formed of a non-magnetic metal having a plurality of salient poles formed on the outer peripheral side surface of the half cup and having an opening angle of 180 degrees or less when viewed from the plane. consists armature coils arranged on the pole, the commutator integrated with the eccentric non-magnetic core to provide the proper power to the armature coil, the eccentric non-magnetic co
Is used for the common connection part of the armature coil, and the eccentricity
The non-magnetic core and the armature coil are integrated with a slidable resin body
And, polarization <br said constitutes a part of a resin bearing portion of the sliding resin body, to have a pair of brushes implanted in the portion of the housing at the proximal end with sliding contact tip to said commutator This can be achieved with a radial air gap type vibration motor having a non-magnetic core. In addition, as described in claim 2, the case and the end bracket
Racket housing and part of the housing
N and S alternate so that the magnetic field is generated in the radial direction.
A magnet having a plurality of magnetic poles magnetized in
Case to face the magnet through a radial gap
It is rotatably mounted on the housing via a shaft fixed to
Equipped with half cup type eccentric rotor with one side cut out
The eccentric rotor is arranged on the outer peripheral side surface of the half cup and is flat.
It was formed so that the opening angle was within 180 degrees when viewed from the surface.
Eccentricity formed by high density resin body with multiple salient poles
Non-magnetic core and armature coils arranged on these salient poles
And eccentric to power this armature coil properly
Comprising a commutator integrated with a non-magnetic core,
The eccentric non-magnetic core and the armature coil are made of a slidable resin body.
It is embodied and the resin bearing part is composed of a part of the slidable resin body.
Then, slide the tip to the commutator and
Has a pair of brushes implanted in a part of the housing.
With radial air gap type vibration motor with eccentric non-magnetic core
Can also be achieved. By doing this, although it is a cored type that has a core inside the coil, it is not a magnetic core, so it is not affected by the magnet, cogging torque is eliminated, and the weight portion such as the coil comes to the outer peripheral portion in the radial direction. A radial air gap type vibration motor capable of

[0009]

【Example】
Next, as a first embodiment of the present invention, the configuration of a vibration motor having a shaft-fixed eccentric non-magnetic core will be described with reference to a longitudinal sectional view of a main part shown in FIG. 1 and a horizontal sectional view of the main part shown in FIG. In FIG. 1, a housing H is made of a shallow cylinder and has a case 1 in which a burring portion 1a of a drawing method is arranged in the center and an end bracket 2 attached to an opening edge of the case 1. A shaft S is fixed inside the housing H by press-fitting it into the burring portion 1a, and an eccentric non-magnetic core 3 formed by brass die-casting slides on the shaft S. Resin J
The half-cup type eccentric rotor R integrally formed with No. 1 is rotatably mounted via the resin bearing portion Ja. Inside the eccentric rotor R, a ring-shaped magnet 4 made of a neodymium bond magnet is fixed via a radial gap by fitting the inner diameter portion into the burring portion 1a.
As shown in FIG. 2, the non-magnetic core 3 of the eccentric rotor R has three protrusions subjected to insulation treatment Jb at a pitch of about 60 to 70 degrees with the opening angle being biased within 180 degrees as a whole when viewed from the plane. The poles 3a, 3b and 3c are provided and are respectively equipped with three air core armature coils 5a, 5b and 5c. On the end bracket side of the non-magnetic core 3 of the eccentric rotor R, six noble metal segment patterns 6a, 6b, ... 6f are formed on one surface, and segments facing each other through a through hole on the other surface are short-circuited. A flat plate commutator 6 made of a printed wiring board is attached via an adhesive material 7, and electric power is received from a pair of brushes 8, 8 planted in the end bracket 2 via a brush base 2a made of a flexible substrate. There is. Each of the terminals of the three air-core armature coils 5a, 5b and 5c is a predetermined segment pattern 6a, 6 of the flat plate commutator 6.
Solder connection is made to each of b ... 6f. The eccentric rotor R can be used in the same configuration as it is, but in the present embodiment, further three air-core armature coils 5a, 5b and 5 are used.
This portion Jb is covered with the above-mentioned slidable resin J1 for the purpose of protecting c and its terminal. That is, it is preferable that the slidable resin J1 be integrated after all the processing operations. W in the figure
Is a thrust washer for controlling the vertical movement of the eccentric rotor R.

Next, the principle of rotation of such a radial air gap type vibration motor in the case of the delta connection type will be described with reference to FIG. 3. Before that, if the connection relationship is clarified in the same figure, the salient pole 3a is formed. The winding start terminal of the arranged armature coil 5a is connected to the segment 6a of the commutator 6, and the winding end terminal thereof is connected to the segment 6b. The winding start end of the armature coil 5b wound around the salient pole 3b is further connected to the segment 6b, and the winding end end of the coil is connected to the segment 6c. The winding start terminal of the armature coil 5c wound around the salient pole 3c is further connected to the segment 6c, and the winding end terminal is connected to the segment 6d having the same potential as the segment 6a. Now, when electric power is applied to the pair of brushes 8 having an arrangement opening angle of 90 degrees arranged substantially at the center of the magnetic pole in the figure, the armature coil 5a is indicated by the arrow A to the armature coil 5a through the segment 6a of the commutator 6. A current flows in the direction, and a rotational force that moves in the A direction is generated based on Fleming's left-hand rule. The current flowing through the armature coil 5c through the segments 6a to 6d flows through the armature coil 5b through the segment 6c, and similarly, a rotational force that moves in the A direction is generated. In the figure, the position when the eccentric non-magnetic cored rotor R is further rotated by each angle is shown. In either case, the neutral portion of the magnetic pole is skillfully used to rotate in the A direction without generating anti-torque to the outside. At this time, since each salient pole 3a, 3b, 3c is non-magnetic, there is no cogging torque, and the salient poles 3a, 3b, and 3c rotate smoothly like a coreless type. Although the above description is based on the delta connection type, it is also possible to form a star connection by changing the relative positions of the magnet and the brush. In the case of this star connection, it is desirable to use each salient pole for the common connection electrode.

FIG. 4 is a cross-sectional view of an essential part showing a modified configuration example of the above embodiment, in which an eccentric non-magnetic core is formed of a high density resin J2. Even in this case, a large amount of movement of the center of gravity can be obtained.

FIG. 5 is a longitudinal sectional view of an essential part of a shaft-rotating type as a second embodiment of the present invention. That is, a bearing holder 11a composed of a plurality of protruding columns is provided in the center of the case 11, and a hollow bearing M is fitted into the bearing holder 11a to form a high density resin J as an eccentric rotor R1.
It is attached to the rotation itself via the shaft S2 integrally formed with 1. The base end of the shaft S2 is pivotally supported on the receiving portion 11b integral with the case via a sliding contact plate 11c. Since the other structures are similar to those of the above-described embodiments, the same reference numerals are given and the description thereof is omitted.

FIG. 6 is a cross-sectional view of essential parts showing the features of the construction of the third embodiment of the present invention. That is, each salient pole 3
Each blade 33a, 33b at the tip of a, 3b and 3c
And 33c to provide armature coils 5a, 5b and 5
c is made to be able to be wound like an ordinary cored. In this case, for example, the eccentric core made of the high-density resin J2 can be directly wound, so that the workability is good, the centrifugal force can be increased by each blade, and the eccentric core has a relatively large radial direction. It will be suitable.
Further, in each of the above embodiments, the armature coil is described as the delta connection, but it is needless to say that the arm connection may be performed by the star connection.

[0014]

【The invention's effect】
According to the present invention, as described above, the eccentric rotor is composed of an eccentric non-magnetic core having a plurality of salient poles which are formed so as to have an opening angle of 180 degrees or less when viewed from the plane. However, it is possible to obtain large vibration in the rotor itself, which is advantageous in terms of cost.

[Brief description of drawings]

FIG. 1 is a vertical cross-sectional view of a main part of a first embodiment of a radial air gap type vibration motor including an eccentric non-magnetic core according to the present invention.

FIG. 2 is a lateral cross-sectional view of a main part of the core of the same example.

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

FIG. 4 is a longitudinal sectional view of a main part of a modified example of the embodiment.

FIG. 5 is a longitudinal sectional view of a main part of the second embodiment.

FIG. 6 is a plan view of an essential part of a third embodiment of the present invention.

FIG. 7 is a perspective view of a conventional cylindrical vibration motor.

[Explanation of symbols]

H housing 1, 11 cases 2 End bracket R, R1, R2 eccentric rotor 3 Eccentric non-magnetic core 3a, 3b, 3c, salient pole 33a, 33b, 33c, blade 4 magnets S, S1 axis 5 armature coil 6 Flat plate commutator 6a-6f segment pattern 8 brushes J1, J2 resin

Continuation of front page (56) Reference JP-A-6-261502 (JP, A) JP-A-7-303349 (JP, A) JP-A-6-141500 (JP, A) JP-A-4-183240 (JP , A) JP-A-6-205564 (JP, A) US Pat. No. 5036239 (US, A) (58) Fields investigated (Int. Cl. ⁷ , DB name) H02K 7/065, 23/04, 23/58

Claims (2)

(57) [Claims] 1. A housing including a case and an end bracket, and a magnet having a plurality of magnetic poles, which are mounted on a part of the housing and are alternately magnetized in N and S so as to generate a magnetic field in a radial direction. Ke as to face via the radial air gap to the magnet
A semi-cup type eccentric rotor, which is rotatably stored in the housing via a shaft fixed to the base, is cut away on one side, and the eccentric rotor is arranged on an outer peripheral side surface of the semi-cup and is open when viewed from a plane. An eccentric non-magnetic core formed by a non-magnetic metal having a plurality of salient poles formed so that the angle is within 180 degrees, an armature coil arranged on these salient poles, and an armature coil suitable for this armature coil. consists of a commutator integrated with the eccentric non-magnetic core to provide power to, the eccentric non-magnetic core to a common connection portion of the armature coils
Using the eccentric non-magnetic core and the armature coil, a slidable resin body
In integrated, the Configure resin bearing portion in a part of the sliding resin body, to have a pair of brushes implanted in the portion of the housing at the proximal end with sliding contact tip to said commutator < A radial air gap type vibration motor with an eccentric non-magnetic core. 2. A howe comprising a case and an end bracket.
Mounted on a part of the housing and generates a magnetic field in the radial direction.
Has a plurality of magnetic poles that are alternately magnetized so that
Magnet and the magnet so that they face the magnet through a radial gap.
Freely rotatable in the housing via a shaft fixed to the base
Half cup type eccentric rotor with one side cut away
The eccentric rotor is arranged on the outer peripheral side surface of the half cup and is a flat surface.
Multiples formed with an opening angle of 180 degrees or less
Eccentric non-magnet formed by high-density resin body with individual salient poles
Magnetic core, the armature coils placed on these salient poles, and the eccentric non-magnet to properly power the armature coils.
And a commutator integrated with a flexible core, wherein the eccentric non-magnetic core and the armature coil are slidable resin bodies.
, The resin bearing part is composed of a part of the slidable resin body, and the tip is slidably contacted with the commutator and the base end is
Has a pair of brushes implanted in a part of the housing
Radial air gap type vibration motor with eccentric non-magnetic core.