JP2010068608A - Coreless motor - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a coreless motor capable of easily adjusting balance of a rotor without requiring machining. <P>SOLUTION: The coreless motor 1 includes a cup-type rotor 2 equipped with a cylindrical coil 5, a stator 3 consisting of a permanent magnet fixed inside the rotor 2 and a housing 4 for housing the stator 3 and the rotor 2. In the coreless motor 1, a clip-like balance weight 15 made of an elastic member having a U-shaped or laterally U-shaped cross section having a pinching portion 15a is pinchingly attached on the periphery of an opening end of the coil 5. Further, the balance weight 15 is pinchingly attached on the peripheral edge of the coil 5, and bonded using a thermosetting adhesive. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a coreless motor having a cup-type rotor provided with a cylindrical coil.

  This type of coreless motor having no core includes a cup-type rotor having a cylindrical coil, a stator composed of a permanent magnet fixed inside the rotor, and the stator and the rotation. Although it is configured to include a housing that accommodates the child, it is used in, for example, a drive source of a radio control model, a monitoring camera, a medical device, and the like because it can be downsized.

  In such a coreless motor, when an imbalance occurs in a rotor that rotates at high speed, vibration and noise are generated, and normal operation becomes impossible.

  Therefore, the balance of the rotor has been conventionally adjusted. For example, after assembling the rotor, the balance measurement device measures the unbalance position and the unbalance amount of the rotor, and the rotor is based on the measurement result. After the balance adjustment putty is attached to the balance, the balance is adjusted again by measuring the unbalance position and the unbalance amount of the rotor with the balance measuring device. The unbalance amount of the rotor is within the predetermined allowable range. The method of repeating the above work until entering.

Further, Patent Document 1 proposes a technique for adjusting the balance of the rotor by forming a plurality of holes in the rotor core and attaching a balance adjusting pin to the holes by a method such as press fitting.
JP 2004-159474 A

  However, with the method of attaching the balance adjustment putty to the rotor, the balance adjustment putty may fall off due to centrifugal force during the rotation of the rotor, and it is necessary to take countermeasures. There is a problem that man-hours are large.

  Moreover, in the technique described in Patent Document 1, it is necessary to separately process a hole for mounting the balance adjustment pin on the rotor core, which requires extra processing steps.

  The present invention has been made in view of the above problems, and an object of the present invention is to provide a coreless motor that can easily adjust the balance of a rotor without requiring processing.

  In order to achieve the above object, a first aspect of the present invention provides a cup-type rotor having a cylindrical coil, a stator composed of a permanent magnet fixed inside the rotor, and the stator. And a coreless motor having a housing for accommodating the rotor, a clip-shaped balance weight made of an elastic member having a U-shaped or U-shaped cross section having a clamping portion is sandwiched between the open end periphery of the coil. It is characterized by that.

  The invention according to claim 2 is characterized in that, in the invention according to claim 1, the balance weight is sandwiched between peripheral edges of the open ends of the coil and bonded with a thermosetting adhesive.

  The invention according to claim 3 is the invention according to claim 1 or 2, wherein the balance weight is made of a nonmagnetic material.

  The invention according to claim 4 is the invention according to any one of claims 1 to 3, wherein the contact surface of the holding portion of the balance weight with the coil is a convex curved surface along the axial direction of the coil. To do.

  According to a fifth aspect of the present invention, in the invention according to any one of the first to fourth aspects, the contact surface of the holding portion of the balance weight with the coil is an arc curved surface that follows the curvature in the circumferential direction of the coil. Features.

  According to the first aspect of the invention, the balance of the rotor can be easily adjusted without requiring any processing of the rotor by sandwiching the clip-shaped balance weight at the unbalanced position of the open end periphery of the existing coil. The balance weight does not fall off during rotation. In addition, a balance weight made of an elastic member having a U-shaped or U-shaped cross section can be elastically deformed and easily attached to the periphery of the open end of the coil. Differences in coil thickness due to differences in wire diameter and winding method Can respond flexibly.

  According to the invention described in claim 2, since the balance weight is sandwiched between the open end periphery of the coil and bonded with the thermosetting adhesive, the balance weight is more reliably removed by the centrifugal force during rotation. In addition to being prevented, it is possible to easily adjust the position of the balance weight before bonding.

  According to the third aspect of the present invention, by configuring the balance weight with a nonmagnetic material, the magnetic field generated in the coil is not affected by the balance weight, and the rotor can be rotated stably.

  According to the fourth aspect of the present invention, the contact surface of the balance weight holding portion to the coil is a convex curved surface along the axial direction of the coil, so that the contact surface of the balance weight to the coil is smooth and the contact area is small. Thus, the balance weight can be attached smoothly, and the coil can be prevented from being damaged.

  According to the fifth aspect of the present invention, since the contact surface of the balance weight holding portion to the coil is an arc curved surface that follows the curvature in the circumferential direction of the coil, the balance weight can be securely attached to the coil. The balance weight can be easily slid to adjust its position.

  Embodiments of the present invention will be described below with reference to the accompanying drawings.

  FIG. 1 is a half sectional view of a coreless motor according to the present invention, FIG. 2 is a side sectional view of a rotor of the coreless motor, and FIG. 3 is a partial view in the direction of arrow A in FIG.

  As shown in FIG. 1, the coreless motor 1 according to the present invention includes a cup-type rotor 2, a stator 3 made of a permanent magnet fixed inside the rotor 2, and these rotors 2. A housing 4 for housing the stator 3 is provided.

  As shown in FIG. 2, the rotor 2 includes a cylindrical coil 5 formed by winding a conducting wire, and a disk-like shape fitted on the inner periphery of one end (right end in FIG. 2) in the axial direction of the coil 5. The support plate 6 includes a rotation shaft 7 inserted and supported at the center of the support plate 6, and a commutator piece (commutator) 8 attached to the support plate 6. 5 is electrically connected via a tap (not shown).

  As shown in FIG. 1, a brush base 9 is fitted on the inner periphery of one end of the housing 4 in the longitudinal direction (the right end in FIG. 1), and the commutator is disposed on the inner peripheral portion of the brush base 9. A brush 10 that contacts the piece 8 is held. A plurality of terminals 11 extend from the brush 10, and these terminals 11 are connected to a power source (not shown). In addition, you may comprise the terminal 11 with a lead wire.

  Further, a bearing housing 12 is attached to the other longitudinal end of the housing 4 (the left end in FIG. 1), and two bearings 13 and 14 are held in the bearing housing 12 at appropriate intervals in the axial direction. ing.

  Thus, in the coreless motor 1, the rotor 2 is rotatably accommodated in the housing 4, and the stator 3 is fixed inside thereof, but the rotating shaft 7 of the rotor 2 is a bearing housing. 12 is rotatably supported by the bearings 13 and 14 held by the motor 12.

  In the coreless motor 1 configured as described above, when the coil 5 of the rotor 2 is energized from the power source (not shown) through the terminal 11, the brush 10, the commutator piece 8, and the tap (not shown), The rotor 2 is rotationally driven at a predetermined speed by the generated magnetic force and the magnetic force of the stator 3.

  By the way, when the rotor 2 is unbalanced, vibration and noise are generated by the rotation of the rotor 2, and the stable operation of the coreless motor 1 becomes impossible.

  Therefore, in the present embodiment, the clip-shaped balance weight 15 provided with the clamping portion 15 a is clamped at the unbalanced position on the periphery of the open end of the coil 5. Here, the unbalance position and the unbalance amount of the rotor 2 are measured by a balance measuring device (not shown), and the balance weight 15 having a size (mass) corresponding to the measured unbalance amount is the peripheral edge of the open end of the coil 5. It is clamped at the unbalanced position. Many balance weights 15 having different masses and sizes are prepared.

  Thus, in the present embodiment, the balance weight 15 is sandwiched around the open end periphery of the coil 5 and bonded with a thermosetting adhesive. Specifically, a thermosetting adhesive is applied to the holding portion 15 a of the balance weight 15, the holding portion 15 a is fitted into the open end periphery of the coil 5, and the balance weight 15 is sandwiched between the open end periphery of the coil 5. Thereafter, the balance weight 15 is moved in the circumferential direction on the coil 5 to adjust the position. When the position of the balance weight 15 is determined, heat is applied to cure the thermosetting adhesive, and the balance weight 15 is moved to the coil 5. Adhere to. When a thermosetting adhesive is used for bonding the balance weight 15 in this way, the balance weight 15 can be easily adjusted on the coil 5 before the balance weight 15 is bonded to the coil 5.

  As shown in FIGS. 1 and 2, the balance weight 15 is formed of a non-magnetic elastic member having a U-shaped or U-shaped cross section, and the elastic member is a resin material such as POM, PET, PBT, or the like. Or a nonmagnetic material is used suitably.

  Further, the contact surface of the sandwiching portion 15a of the balance weight 15 with the coil 5 is an arc surface along the inner and outer peripheral surfaces of the coil 5, and the balance weight 15 is attached to the coil 5 as shown in FIG. In the attached state, it is formed in a fan shape when viewed from the axial direction of the coil 5. For this reason, the balance weight 15 is firmly fixed to the coil 5 in a state in which the entire surface of the sandwiched portion 15 a is in close contact with the inner and outer peripheral surfaces of the coil 15 when the balance weight 15 is attached to the open end edge of the coil 5.

  As described above, in the present embodiment, the clip-shaped balance weight 15 is sandwiched between the unbalanced positions of the open end periphery of the existing coil 5, and thus the rotor 2 can be easily processed without any processing. Further, the balance of the rotor 2 can be adjusted, and the balance weight 15 does not fall off during the rotation. In particular, in the present embodiment, the balance weight 15 is sandwiched around the open end periphery of the coil 5 and bonded with a thermosetting adhesive, so that the balance weight 15 from the coil 5 due to the rotating centrifugal force is rotating. The falling off can be prevented more reliably, and the position of the balance weight 15 can be easily adjusted before bonding.

  Further, the balance weight 15 made of an elastic member having a U-shaped or U-shaped cross section can be elastically deformed and easily attached to the periphery of the open end of the coil 5, and the thickness of the coil 5 due to the difference in wire diameter or winding method. It is possible to flexibly cope with the difference.

  Furthermore, since the balance weight 15 is made of a nonmagnetic resin material or a nonmagnetic material, the magnetic field generated in the coil 5 is not affected by the balance weight 15 and the rotor 2 can be stably rotated.

  Here, another form of the balance weight 15 is shown in FIGS. 4A to 4C are cross-sectional views taken along the line BB of FIG. 3 showing another form of the balance weight.

  In the balance weight 15 shown in FIG. 4A, the contact surface of the sandwiching portion 15a with the inner and outer peripheral surfaces of the coil 5 is a convex curved surface along the axial direction of the coil 5 (left-right direction in the figure). In the balance weight 15 shown in FIG. 5, only the contact surface of the sandwiching portion 15 a with the outer peripheral surface of the coil 5 is a convex curved surface along the axial direction of the coil 5. The contact surface is smooth and the contact area is kept small, the balance weight 15 can be attached smoothly, and damage to the insulating layer of the coil 5 can be prevented.

  Further, the balance weight 15 shown in FIG. 4C has a protrusion 15 b protruding from a part of the contact surface of the sandwiching portion 15 a with the outer peripheral surface of the coil 5, and this protrusion 15 b is the outer peripheral surface of the coil 5. The balance weight 15 can be prevented from falling off from the coil 5 more reliably. Here, by forming the protrusion 15b as a convex curved surface along the outer peripheral surface of the coil 5, the contact surface of the balance weight 15 to the coil 5 is smooth and the contact area is kept small, and the balance weight 15 is attached smoothly. In addition, the coil 5 can be prevented from being damaged.

It is a half cut sectional view of the coreless motor concerning the present invention. It is a sectional side view of the rotor of the coreless motor which concerns on this invention. FIG. 3 is a partial view in the direction of arrow A in FIG. 2. (A)-(c) is a BB line sectional view of Drawing 3 showing various forms of a balance weight.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Coreless motor 2 Rotor 3 Stator 4 Housing 5 Coil 6 Support plate 7 Rotating shaft 8 Commutator piece 9 Brush stand 10 Brush 11 Terminal 12 Bearing housing 13, 14 Bearing 15 Balance weight 15a Balance weight holding part 15b Balance weight Protrusion

Claims (5)

In a coreless motor provided with a cup-shaped rotor having a cylindrical coil, a stator made of a permanent magnet fixed inside the rotor, and a housing for housing the stator and the rotor,
A coreless motor characterized in that a clip-shaped balance weight made of an elastic member having a U-shaped or U-shaped cross section having a sandwiching portion is sandwiched around the open end periphery of the coil.   2. The coreless motor according to claim 1, wherein the balance weight is sandwiched between peripheral edges of the open end of the coil and bonded with a thermosetting adhesive.   The coreless motor according to claim 1, wherein the balance weight is made of a nonmagnetic material.   The coreless motor according to any one of claims 1 to 3, wherein a contact surface of the balance weight holding portion with the coil is a convex curved surface along an axial direction of the coil. 5. The coreless motor according to claim 1, wherein a contact surface of the balance weight sandwiching portion with the coil is an arc curved surface along a circumferential curvature of the coil.

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