JP2005080402A - Motor - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To make it possible to favorably prevent change in thrust permission clearances and stably hold a rotor portion through a simple constitution. <P>SOLUTION: Stopper members form the thrust permission clearances S1 and S2 between them and bearing portions 12 and 13, respectively. The stopper members are formed of a pair of bushes 21 and 22 that are respectively abutted against the axial end faces 16a and 16a of a motor core 16 so that the motor core is sandwiched between them from both sides in the axial direction. A connecting member 25 abutted against the protruded-side end face 22c of the bush 22 in the axial direction or a connecting member 24 abutted against the protruded-side end face 21c of the bush 21 is opposedly disposed, so that the thrust permission clearances S1 and S2 are formed between it and the respective bearing portion 13 and 13. Thus, the thrust permission clearances S1 and S2 are so formed that their amounts in the axial direction are unchanged. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to a motor in which a rotor portion including a motor core and a drive coil is held in a thrust direction by a stopper member disposed via a thrust permissible gap including a predetermined minute gap in the axial direction.

  In general, a motor configured to support both end portions of a rotating shaft with a pair of bearing portions made of a metal bearing or the like is widely known. In such a double-end bearing type motor, for example, as shown in FIG. 2, a stopper member is provided for preventing backlash in the thrust direction of the rotor portion R including the motor core 1 and the drive coil 2. It has been.

  As the stopper member, for example, an oil draining member 3 (or commutator 4) and a washer 5 are used, and these stopper members 3 and 5 correspond to each of the pair of bearing portions 6 and 7, respectively. Thus, the minute thrust permissible gaps S are formed by facing each other in the axial direction. By adopting such a configuration in which the thrust permissible gap S is provided, the rotor portion R is stably held without backlash in the axial direction. In particular, the drive coil 2 is attached to the inner wall surface of the motor case 8. Contact is prevented.

  However, in such a motor having a conventional structure, when the rotor portion R vibrates in the axial direction or resonates due to the addition of vibration acceleration in a strong thrust direction such as 30 G level or more, for example. The oil draining member 3 (or commutator 4) and the washer 5 serving as the stopper members described above and the washer 5 may come into contact with the bearing portions 6 and 7 with an excessive force. Misalignment may occur. When the stopper members 3 and 5 are misaligned, the stopper members 3 and 5 approach the motor core 1 and the drive coil 2, and the above-described thrust permissible gap S is expanded and axial backlash increases. If such thrust backlash becomes extremely large, the drive coil 2 of the rotor portion R may come into contact with the inner wall surface of the motor case 8 to cause a disconnection or a commutator (commutator) 4 may have poor conduction.

  SUMMARY OF THE INVENTION An object of the present invention is to provide a motor that can prevent a change in a thrust permissible gap with a simple configuration and can stably hold a rotor portion.

In order to achieve the above object, in the motor according to claim 1 of the present invention, the motor is attached to the rotating shaft so as to form a thrust permissible gap consisting of a predetermined minute gap in the axial direction between each of the pair of bearing portions. The stopper member is inserted into the rotating shaft so as to sandwich the motor core from both sides in the axial direction, and has a pair of bushes fixed in contact with the axial end surfaces of the motor core, The inner diameter portion of the drive coil extends in the axial direction from the axial end surface of the motor core and protrudes to the axially outer region of the drive coil, and contacts the protruding side end surface of each bush or the protruding side end surface of the bush. The connected continuous members are arranged to face each other so as to form the thrust permissible gap with respect to the end surfaces of the bearing portions, so that the thrust permissible gap is in the axial direction. It is formed so as to be variable in void volume.
According to the motor of the first aspect of the present invention having such a configuration, each of the bushes constituting the stopper member forming the thrust allowable gap with respect to each of the pair of bearing portions is in the axial direction of the motor core. Since the stopper members are fixed in contact with the end surfaces, the displacement of the stopper member is reliably prevented, and as a result, the gap amount of the thrust permissible gap is maintained unchanged. ing.

In the motor according to a second aspect of the present invention, the connecting member in the first aspect comprises a commutator, an oil draining member, or a thrust receiving member.
According to the motor of the second aspect having such a configuration, displacement of the commutator, the oil draining member, or the thrust receiving member can be prevented well.

Furthermore, in the motor according to claim 3 of the present invention, the bush in claim 1 is formed of a metal member, and the protruding side end surface of the bush has a flange portion in which the main body of the bush is radially enlarged. It is formed by.
According to the motor of the third aspect having such a configuration, the bush is easily formed by a pressing process or the like, and the contact force with respect to the bearing portion or the connecting member is reduced by the flange portion provided on the bush. It has become so.

Further, in the motor according to claim 4 of the present invention, a connecting member made of a resin material abutting on the protruding side end surface is provided on the protruding side end surface of the bush in which the flange portion is formed in the above fourth aspect. ing.
According to the motor of claim 4 having such a configuration, since the connecting member is formed of a resin material, when the bush is formed of a metal member, the connecting member is likely to crack. By the flange part provided in the bush, the contact force with respect to the connection member of a bush is relieve | moderated effectively, and the crack of a connection member is prevented.

Further, in the motor according to claim 5 of the present invention, the motor core and the bush in claim 1 are integrally insulated and coated.
According to the motor of the fifth aspect having such a configuration, the motor core and the bush are more firmly integrated by integral coating, and the displacement of the stopper member can be further reliably prevented. ing.

  As described above, the motor according to the present invention includes a stopper member attached to the rotating shaft so as to form a thrust permissible gap between each of the pair of bearing portions, and the motor core shaft is sandwiched from both sides in the axial direction. Consists of a pair of bushes that are fixed in contact with the respective direction end faces, and the projecting end faces of the bushes or their connecting members face each other so as to form a thrust permissible gap between the bearings. Since the thrust permissible gap is formed so as to have an invariable gap amount in the axial direction by arranging it, the displacement of the stopper member is surely prevented. Therefore, the reliability of the motor can be improved.

Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.
In the motor according to the embodiment shown in FIG. 1, a pair of metal bearings 12 and 13 are held at both end portions in the axial direction of the case 11 formed so as to form an elongated substantially hollow cylindrical body. . The pair of metal bearings 12 and 13 support an elongated rod-shaped rotating shaft 14 rotatably. In this embodiment, the output gear 15 is fixed by being inserted into the output portion on the left side of the rotary shaft 14 in the press-fitted state.

  A motor core 16 formed by laminating a plurality of magnetic plates is fixed to the rotary shaft 14 so as to be inserted through the rotary shaft 14, and a drive coil 17 is attached to the motor core 16. It is wound. The drive coil 17 is wound so as to protrude from the axial end faces 16 a, 16 a of the motor core 16 toward the outer side in the axial direction (left-right direction in the drawing), and forms a rotor portion R together with the motor core 16. ing.

  A pair of bushes 21 and 22 constituting a stopper member are disposed on both axial sides of the motor core 16. The bushes 21 and 22 in the present embodiment are formed by press-molding a metal member such as brass, and are inserted through the rotary shaft 14 so as to sandwich the motor core 16 from both sides in the axial direction. More specifically, the axially inner end surfaces 21b and 22b of the body barrel portions 21a and 22a of the pair of bushes 21 and 22 are fixed in contact with the axial end surfaces 16a and 16a of the motor core 16 described above. In addition, the inner diameter portion of the drive coil 17 described above extends from the contact portion with the motor core 16 toward the outer side in the axial direction (the left-right direction in the figure), and is more than the axial end surface of the drive coil 17. It protrudes to a region outside in the axial direction (left-right direction in the figure).

  Furthermore, flanges 21c and 22c formed so as to expand in the radial direction are provided at the protruding end portions (the left and right end portions in the drawing) of the bushes 21 and 22, respectively. In the flange portion 21c, a resin main body portion of a commutator (commutator) 23 is disposed as a continuous member, and an end face on the right side of the commutator (commutator) 23 is disposed on the right side of the figure. Similarly, an oil draining member 24 made of a sliding-resistant resin material such as nylon is disposed in a state where the connecting member is in contact with the shaft in the axial direction. A thrust permissible gap S <b> 1 is formed between the end face 24 a on the right side of the oil draining member 24 and the end face 12 a of the metal bearing 12 facing it. Here, on the right side of the motor core 16 in the figure, a stopper member is constituted by the bush 21, the commutator 23 and the oil draining member 24.

  On the other hand, the flange 22c provided on the bush 22 on the left side of the figure is arranged with a thrust receiving member 25 made of a sliding-resistant resin material such as nylon in contact therewith as its continuous member. Between the thrust receiving member 25 and the end surface 13a of the metal bearing 13 facing the thrust receiving member 25, a thrust permissible gap S2 composed of a minute gap is formed. In the state shown in the figure, the rotor portion R is pressed against the left side of the figure by some acting force, and the thrust receiving member 25 is in contact with the end surface 13a of the metal bearing 13 so that the thrust allowable gap S2 is eliminated. However, in the steady rotation state, both the above-described two thrust permissible gaps S1 and S2 are maintained in a state where they are formed together. Here, on the left side of the motor core 16 in the figure, a stopper member is constituted by the bush 22 and the thrust receiving member 25.

  Further, an integral insulation coating is applied, for example, by a plastic coating P from the axial end surfaces 16a, 16a of the motor core 16 to the surfaces of the bushes 21, 22.

  Here, as described above, the bushes 21 and 22 are disposed in contact with the axial end surfaces 16a and 16a of the motor core 16, respectively, and are disposed in contact with the bush 22 on the left side of the drawing. A thrust permissible gap S2 is formed by a thrust receiving member 25 as a continuous member, and a thrust permissible gap S1 is formed by an oil draining member 24 as a continuous member arranged in contact with the bush 21 on the right side of the figure. Since they are formed, the sum (S1 + S2) of these two thrust permissible gaps is formed so as to have a void amount that does not change in the axial direction.

  Thus, in this embodiment, each of the bushes 21 and 22 constituting the stopper member forming the thrust permissible gaps S1 and S2 for each of the pair of metal bearings 12 and 13 is the axial end face 16a of the motor core 16, Since they are fixed in contact with each other, the displacement of the bushes 21 and 22 constituting the stopper member is surely prevented. As a result, the amount of the clearance between the thrust permissible gaps S1 and S2 is reduced. It has been maintained unchanged.

  In particular, in this embodiment, the connecting member for the right-side bush 21 is composed of the commutator 23 and the oil draining member 24. Therefore, the positional deviation between the commutator 23 and the oil draining member 24 is also good. It is to be prevented.

  Furthermore, in this embodiment, since the bushes 21 and 22 are formed of a metal member, the bushes 21 and 22 are easily formed by a pressing process or the like, and on the protruding end side of the bushes 21 and 22, Since the enlarged flange portions 21c and 22c are provided, the contact force of the flange portions 21c and 22c with respect to the main body portion of the commutator 23 or the thrust receiving member 25 which is a connecting member formed of a resin material. Has been relaxed. Therefore, cracking of the main body portion of the commutator 23 or the thrust receiving member 25 is effectively prevented.

  Furthermore, in this embodiment, since the motor core 16 and the bushes 21 and 22 are integrally insulated, the motor core 16 and the bushes 21 and 22 are more firmly integrated by the integral coating. The positional deviation of the bushes 21 and 22 as stopper members is prevented more reliably.

  As mentioned above, although the embodiment of the invention made by the present inventor has been specifically described, the present invention is not limited to the above-described embodiment, and various modifications can be made without departing from the scope of the invention. Not too long.

  For example, in the above-described embodiment, the present invention is applied to a motor with a brush, but the present invention can be similarly applied to a motor having a brushless structure. That is, on the right side (see FIG. 1) of the motor core 16 in the above embodiment, the thrust receiving member does not have the commutator 23 or the oil draining member 24 and is in contact with the flange portion 21c provided on the bush 21. The present invention can also be applied to a motor in which is arranged.

  Further, when the bushes 21 and 22 are formed of a resin material, the present invention can be applied to a motor that does not have a thrust receiving member and the stopper member is configured only by the bushes 21 and 22. It is. Moreover, it is not limited to the thing of the said embodiment of a bush shape, For example, a cylindrical bush may be sufficient.

  The motor according to the present invention described above is widely used for both-end bearing type motors configured to support both end portions of a rotating shaft with a bearing such as a brushless motor, such as a brushless motor. It is possible.

It is a longitudinal section explanatory view showing the schematic structure of the motor in one embodiment of the present invention. It is longitudinal cross-sectional explanatory drawing showing schematic structure of the general motor of a both-ends bearing type.

Explanation of symbols

11 MOASE 12, 13 Metal bearing 14 Rotating shaft 16 Motor core 16a Motor core axial end surface 17 Drive coil R Rotor part 21, 22 Bushing 21a, 22a Body trunk part 21c, 22c ridge part 23 Commutator (communicator) (continuous member)
24 Oil draining member (continuous member)
25 Thrust receiving member (continuous member)
S1, S2 Thrust allowable clearance

Claims (5)

A rotation axis;
A motor core fixed by being inserted through the rotating shaft;
A drive coil wound around the motor core and provided so as to protrude from both axial end faces of the motor core toward both sides in the axial direction;
A rotor portion including the motor core and a drive coil;
A pair of bearing portions disposed on both axial sides of the rotor portion and rotatably supporting the rotating shaft;
A stopper member attached to the rotary shaft so as to form a thrust permissible gap consisting of a predetermined minute gap in the axial direction between each of the pair of bearing portions,
In motors with
The stopper member has a pair of bushes that are inserted in the rotating shaft so as to sandwich the motor core from both sides in the axial direction and fixed in contact with the axial end surfaces of the motor core, respectively.
Each bush extends from the axial end face of the motor core in the axial direction to the inner diameter portion of the drive coil and protrudes to the axially outer region of the drive coil,
The projecting side end surfaces of the bushes or the connecting members that are in contact with the projecting side end surfaces of the bushes are arranged so as to face the end surfaces of the bearing portions so as to form the thrust permissible gaps. The motor is characterized in that the thrust permissible gap is formed so as to have an invariable gap amount in the axial direction. 2. The motor according to claim 1, wherein the connecting member comprises a commutator, an oil draining member, or a thrust receiving member. The bush is formed of a metal member;
The motor according to claim 1, wherein the projecting side end surface of the bush is formed by a flange portion obtained by enlarging a body body portion of the bush in a radial direction. The motor according to claim 4, wherein a connecting member made of a resin material in contact with the protruding side end surface is provided on the protruding side end surface of the bush in which the flange portion is formed. The motor according to claim 1, wherein the motor core and the bush are integrally coated with insulation.

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