JP4887064B2 - Small motor - Google Patents

Description

  The present invention relates to a small motor such as a vibration motor, and more particularly to a housing structure.

In a vibration motor in which an eccentric weight is attached to a shaft of a motor with a brush, as shown in, for example, Japanese Patent Application Laid-Open No. 2005-312282, a center plate is left by press molding while leaving an outer end plate at one end of a body plate The housing has a burring portion that protrudes outward in the axial direction, and a metal bearing that is press-fitted into the burring portion, and the burring portion is used as a bearing holder.
Japanese Patent Laying-Open No. 2005-312282 (FIG. 2)

  However, when a metal bearing is press-fitted into the burring part, the metal bearing may be eccentric or inclined due to molding accuracy of the burring part or a press-fitting failure, resulting in variations in the sliding loss of the metal bearing and yield. Cause a decline.

  Accordingly, in view of the above problems, an object of the present invention is to provide a small motor that can reduce variations in sliding loss of a metal bearing due to eccentricity or inclination of the metal bearing and can improve yield.

In order to solve the above-mentioned problems, the present invention has a housing having a burring portion that protrudes outward in the axial direction while leaving an outer peripheral end plate portion at one end of a body plate portion, and is press-fitted into the burring portion. A small motor having a metal bearing, a motor shaft rotatably supported by the metal bearing, and a coil winding wound around a salient pole of an armature core through which the motor shaft is inserted. against an end face on the inner surface of the end plate portion provided with a permanent magnet surrounding the inner surface of the shell plate portion, burring portion inner diameter substantially equal to the inner diameter, including press-fitting portion of the metal bearing is a permanent magnet, electrical There is a bearing nonoccupying space between the bearing side end of the child core and the core side end of the metal bearing, and the swollen winding portion that bulges from the bearing side end of the armature core to the metal bearing side of the coil winding. Characterized by being in a non-occupied space for bearings That.
The present invention also includes a housing having a burring portion that protrudes outward in the axial direction while leaving the outer end plate at one end of the body plate portion, a metal bearing press-fitted into the burring portion, A small motor having a motor shaft rotatably supported by the metal bearing and a coil winding wound around a salient pole of an armature core through which the motor shaft is inserted. A permanent magnet that circulates the inner surface of the body plate portion with its end face applied to the side surface, and the burring portion including the press-fit portion of the metal bearing has an inner diameter substantially equal to the outer diameter of the armature core. There is a bearing non-occupying space between the bearing side end and the metal bearing core side end, and the swollen winding part that bulges from the armature core bearing side end to the metal bearing side of the coil winding is the bearing non-occupying Characterized by being in a space.

  The burring part is not only used as a bearing holder for metal bearings, but also in order to secure a non-occupying space for the bearing and insert the swollen part of the coil winding into this space. Since it is necessary to increase the inner diameter of the metal bearing as it approaches the outer diameter of the armature core, the outer diameter of the metal bearing (inner diameter of the burring part) should also be increased until it approaches the outer diameter of the armature core. Therefore, since a metal bearing having a large ratio of the outer diameter to the inner diameter is used, the eccentricity or inclination posture of the metal bearing can be suppressed, variation in sliding loss can be reduced, and the yield can be improved. In addition, since the swollen winding portion of the coil winding can be accommodated in the bearing non-occupying space in the burring processing portion, it contributes to the realization of a short body plate motor or the expansion of the coil winding line product.

  Conventionally, the thickness of the metal bearing is generally larger than the diameter of the motor shaft, but if the thickness of the metal bearing is less than the diameter of the motor shaft, the sliding loss of the metal bearing itself can be reduced. Further, since the thickness of the non-occupied space of the bearing is also increased, it contributes to the realization of a motor with a shorter body plate portion or the expansion of the coil winding line area.

The inner diameter of the burring portion rather inside diameter substantially equal to the permanent magnet, or, since the outer diameter of the armature core becomes an inner diameter substantially equal to the burring portion, blister from the bearing end of the armature core All the winding portions can be accommodated in a non-bearing space, and the effect of shortening the trunk plate portion or increasing the coil winding line area becomes remarkable.

  In addition, when an eccentric weight is attached to a portion of the motor shaft that protrudes outward from the metal bearing, a vibration motor can be realized, but the eccentricity or inclination posture of the metal bearing is suppressed. Therefore, it is possible to provide a vibration motor that reduces the sliding loss against the side pressure of the motor shaft caused by the rotation of the eccentric weight.

  ADVANTAGE OF THE INVENTION According to this invention, the eccentricity or inclination attitude | position of a metal bearing can be suppressed, the variation in a sliding loss can be reduced, and a yield improves. In addition, since the swollen winding portion of the coil winding can be accommodated in the bearing non-occupying space in the burring processing portion, it contributes to the realization of a short body plate motor or the expansion of the coil winding line product.

  Next, embodiments of the present invention will be described with reference to the accompanying drawings. FIG. 1 is a longitudinal sectional view showing a vibration motor according to an embodiment of the present invention.

  This vibration motor includes a housing 10 having a burring portion 3 that protrudes outward in the axial direction by press molding, leaving an outer peripheral end plate portion 2 at one end of a body plate portion 1 of magnetic material, and burring processing. A first metal bearing 11 that is press-fitted to the inner end of the portion 3, an end cover 12 made of insulating resin that closes the other end opening of the body plate portion 1, and a bearing holder portion 12 a of the end lid 12. A second metal bearing 13 housed in the motor shaft 14, a motor shaft 14 rotatably supported by the first metal bearing 11 and the second metal bearing 13, an armature core 15 through which the motor shaft 14 is inserted, and the electric machine A coil winding 16 wound around the salient pole 15a of the child core 15, a commutator 19 attached to a resin commutator holder 17 through which the motor shaft 14 is inserted and attached by a fastening ring 18, and Ring bar mounted on riser 19a of commutator 19 A star 20, a permanent magnet 21 fixed around the inner surface of the body plate portion 1, and an eccentric weight 22 made of heavy metal attached to a portion of the motor shaft 14 protruding outward from the first metal bearing 11; have.

  A terminal (not shown) of the coil winding 16 is entangled with the riser 19a and soldered together with an electrode (not shown) of the ring varistor 20. The end lid 12 supports a pair of brushes (not shown) for making sliding contact with the commutator 19. Reference numeral 23 denotes an external connection motor terminal.

  The armature core 15 is formed by laminating a large number of magnetic plates, and a bush 24 composed of a plurality of insulating resin washers W is fitted to the motor shaft 14 at the first bearing side end A thereof. The end surface 21 a of the permanent magnet 21 is in contact with the inner side surface 2 a of the outer peripheral side end plate portion 2, and the inner side surface 2 a is a positioning stopper portion of the permanent magnet 21. The burring portion 3 has a bearing nonoccupying space S between the first bearing side end A of the armature core 15 and the core side end B of the first metal bearing 11. In the coil winding 16, the swollen winding portion 16 a that bulges from the first bearing side end A of the armature core 15 toward the first metal bearing 11 enters the bearing nonoccupying space S and is accommodated. .

  The thickness of the first metal bearing 11 is about 3/4 of the diameter of the motor shaft 14 or less. The inner side surface 2a of the outer peripheral side end plate portion 2 and the first bearing side end A of the armature core 15 are at the same level, and the distance from the inner side surface 2a to the inner side surface C of the edge portion 3a of the burring portion 3 Is about 7/3 of the thickness of the first metal bearing 11, and the thickness of the non-occupied space S is about 4/3 of the thickness of the first metal bearing 11. Further, the inner diameter of the burring portion 3 is equal to the inner diameter of the permanent magnet 21.

  In this example, not only the burring portion 3 is used as a bearing holder for the first metal bearing 11, but also a sufficient bearing non-occupying space S is secured and the swollen winding portion 16 a of the coil winding 16 is inserted into this space S. In order to configure in this way, the outer diameter of the first metal bearing 11 (burring) must be increased as the inner diameter of the burring portion 3 approaches the outer diameter of the armature core 15 as compared with the conventional case. Since the inner diameter of the processed portion 3 is also increased until it approaches the outer diameter of the armature core 15, the first metal bearing 11 having a large ratio of the outer diameter to the inner diameter is used. For this reason, the eccentricity or the inclination posture of the first metal bearing 11 can be suppressed, the variation of the sliding loss can be reduced, and the yield is improved. In addition, since the swollen winding portion 16a of the coil winding 16 can be accommodated in the bearing nonoccupying space S in the burring portion 3, it contributes to the realization of a vibration motor of the short body plate portion 1 or a reduction in current. .

  Further, since the thickness of the first metal bearing 11 is made smaller than the diameter of the motor shaft 14, the sliding loss of the first metal bearing 11 itself can be reduced, and the thickness of the non-occupied space S is increased. Therefore, it contributes to the realization of the vibration motor of the short body plate portion 1 or the reduction in current. Further, since the inner diameter of the burring portion 3 is substantially equal to the inner diameter of the permanent magnet 21, the outer diameter of the armature core 15 is also substantially equal to the inner diameter of the burring portion 3. All of the swollen winding portion 16a from the first bearing side end A can be accommodated in the bearing non-occupying space S, and the effect of shortening the shaft or reducing the current of the body plate portion 1 is remarkable.

  In the vibration motor of this example, as the eccentric weight 22 becomes heavier and larger in size, the side pressure of the motor shaft 14 increases and the sliding loss of the first metal bearing 11 closer to the eccentric weight 22 becomes a problem. Since the first metal bearing 11 having a small diameter is used, the problem does not become apparent.

It is a longitudinal cross-sectional view which shows the vibration motor of the Example which concerns on this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 ... Body plate part 2 ... Outer peripheral side end plate part 2a, C ... Inner side surface 3 ... Burring process part 10 ... Housing 11 ... 1st metal bearing 12 ... End cover (end placket)
12a ... bearing holder 13 ... second metal bearing 14 ... motor shaft 15 ... armature core 15a ... salient pole 16 ... coil winding 16a ... swollen winding part 17 ... commutator holder 18 ... fastening ring 19 ... commutator 19a ... Riser 20 ... Ring varistor 21 ... Permanent magnet 21a ... End face 22 ... Eccentric weight 23 ... Motor terminal 24 for external connection ... Bush A ... First bearing side end B of armature core ... Core side end C of first metal bearing ... Burring Inner side surface S of edge of processed part ... Bearing nonoccupying space W in burring processed part ... Insulating resin washer

Claims (4)

A housing having a burring portion that protrudes outward in the axial direction while leaving an outer end plate at one end of the body plate portion, a metal bearing that is press-fitted into the burring portion, and rotates to the metal bearing A small motor having a motor shaft supported in a possible manner and a coil winding wound around a salient pole of an armature core through which the motor shaft is inserted,
The permanent magnet includes a permanent magnet that goes around the inner surface of the body plate portion by applying an end surface to the inner surface of the outer peripheral side end plate portion, and the inner diameter of the burring portion including the press-fit portion of the metal bearing is equal to the inner diameter of the permanent magnet. It is substantially equal, and has a bearing non-occupying space between the bearing side end of the armature core and the core side end of the metal bearing, and the metal from the bearing side end of the armature core in the coil winding A small motor, wherein a swollen winding portion bulging toward a bearing is in the bearing non-occupying space. A housing having a burring portion that protrudes outward in the axial direction while leaving an outer end plate at one end of the body plate portion, a metal bearing that is press-fitted into the burring portion, and rotates to the metal bearing A small motor having a motor shaft supported in a possible manner and a coil winding wound around a salient pole of an armature core through which the motor shaft is inserted,
  A permanent magnet that circulates the inner surface of the body plate portion with an end face applied to the inner surface of the outer peripheral side end plate portion, and the inner diameter of the burring portion including the press-fit portion of the metal bearing is outside the armature core. Substantially equal to the diameter, and has a non-occupying space between the bearing side end of the armature core and the core side end of the metal bearing, and from the bearing side end of the armature core of the coil winding. A small motor, wherein a swollen winding portion bulging toward the metal bearing is in the non-occupying space of the bearing. 3. The small motor according to claim 1 , wherein the thickness of the metal bearing is equal to or less than the diameter of the motor shaft. The small motor according to any one of claims 1 to 3 , wherein an eccentric weight is attached to a portion of the motor shaft that protrudes outward from the metal bearing. .

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