JP2008312344A - Ac generator for vehicle - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an AC generator for a vehicle, capable of preventing an increase in cost caused by an increase the number of parts and improving waterproofness around a brush. <P>SOLUTION: The AC generator includes slip rings 49, 50 provided on a rotary shaft 44 of a rotor; a resin enclosing member for enclosing an ambient space of the slip rings 49, 50 and brushes 72, 73; a rolling bearing box 21 for housing a rolling bearing 46 for rotatably supporting the rotor; and a resin cap 22 inserted between the rolling bearing 46 and the rolling bearing box 21 when the rolling bearing 46 is housed. The rolling bearing box 21 and the resin enclosing member are disposed with an opening 30 formed on a rear side frame sandwiched, and allow one part of the resin cap 22 to fit with one part of the resin enclosing member through the opening 30. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a vehicle AC generator mounted on a passenger car, a truck, or the like.

2. Description of the Related Art Conventionally, a vehicular AC generator is known in which a separate member is interposed between a brush holder and a frame to improve the airtightness of a space around a slip ring (see, for example, Patent Document 1). By using a seal member such as rubber as another member, the airtightness of the space around the slip ring can be enhanced.
JP 2002-125343 A (page 3-5, FIG. 1-12)

  By the way, in the structure disclosed by patent document 1, since a sealing member is needed separately from a brush holder and a slip ring cover, the number of parts increases and the assembly man-hour for that increases, Therefore Inviting cost increase There was a problem. In addition, since this seal member needs to be assembled in a state of being pressed from both sides along the axial direction, if there is a gap on at least one end face side of this seal member due to poor assembly or the like, rainwater or the like may enter. There was a problem that the waterproofness deteriorated.

  The present invention was created in view of the above points, and an object of the present invention is for a vehicle that can prevent an increase in cost due to an increase in the number of parts and can improve waterproofness around the brush. It is to provide an alternator.

  In order to solve the above-described problems, an AC generator for a vehicle according to the present invention includes a slip ring provided on a rotating shaft of a rotor, a resin surrounding member that covers a space around the slip ring and the brush, and a rotating rotor. And a resin cap inserted between the bearing and the bearing housing portion when housing the bearing, and the bearing housing portion and the resin surrounding member are formed on the frame. It arrange | positions on both sides of the opening part used in order to let a shaft pass, and a part of resin cap and a part of resin surrounding member are fitted through the opening part. By directly fitting the resin surrounding member that covers the periphery of the slip ring and the resin cap in the bearing housing portion, the airtightness of the space around the slip ring and the brush is increased without interposing another member therebetween. It is possible to prevent an increase in cost due to an increase in the number of parts and to improve the waterproofness around the brush.

  In addition, the portion where the above-described resin cap and the resin surrounding member are fitted has a cylindrical portion extending in the rotation axis direction, and the tip portions of these two cylindrical portions overlap along the axial direction. It is desirable. Thereby, the flooding from the connection part between a resin surrounding member and a resin cap can be prevented reliably.

  The AC generator for a vehicle according to the present invention includes a slip ring provided on a rotating shaft of a rotor, a resin surrounding member that surrounds a space around the slip ring and the brush, and a bearing that rotatably supports the rotor. A bearing housing portion for housing and a resin cap that is inserted between the bearing and the bearing housing portion when housing the bearing, and the bearing housing portion and the resin surrounding member are used for passing a rotating shaft formed in the frame. The cylindrical portion extending in the rotation axis direction while forming the opening to be formed has a facing surface that overlaps in the rotation axis direction and forms a gap in the radial direction with respect to a part of the resin cap. The elastic member is arrange | positioned between the parts. By fitting the resin surrounding member that covers the periphery of the slip ring and the resin cap in the bearing housing portion through an elastic member, the air tightness of the space around the slip ring and the brush is improved and the waterproof property of the brush periphery is improved. be able to.

  Moreover, the cylinder part mentioned above is cylindrical shape, and O-ring as an elastic member is arrange | positioned in the groove | channel provided in the outer periphery of the small diameter side or the inner side of the large diameter side among a part of the opposing surface and the resin cap. Is desirable. By using an O-ring, airtightness can be reliably increased. Further, since the O-ring only needs to be mounted in the groove in advance, the process of assembling an elastic member as a separate member at the time of assembling is unnecessary, and the assembling process can be simplified.

  Further, it is desirable that the coefficient of thermal expansion on the small diameter side of the opposed surface and part of the resin cap described above is larger than the coefficient of thermal expansion on the large diameter side. Thereby, when temperature rises by electric power generation, it becomes possible to maintain airtightness reliably.

  Hereinafter, an AC generator for a vehicle according to an embodiment to which the present invention is applied will be described in detail with reference to the drawings. FIG. 1 is a diagram showing an overall configuration of an automotive alternator according to an embodiment. A vehicle alternator 100 shown in FIG. 1 includes a front frame 1, a rear frame 2, a stator 3, a rotor 4, a voltage regulator 6, a brush device 7, a rectifier 8, a rear cover 9, and the like. Has been.

  Both the front side frame 1 and the rear side frame 2 have a bowl-like shape, and are fixed to each other by a plurality of bolts in a state where these openings are in direct contact with each other. A stator 3 is fixed to the inner periphery of the front side frame 1. Further, a cylindrical rolling bearing box 11 is integrally formed on the front side frame 1, and a cylindrical rolling bearing box (bearing housing portion) 21 is integrally formed on the rear side frame 2.

  The stator 3 includes a stator core 31 and a stator winding 32. The rotor 4 includes a field winding 41, pole cores 42 and 43, a rotating shaft 44, and the like. A part of the rotating shaft 44 is partly supported by a pair of rolling bearings 45 and 46 fixed to the rolling bearing boxes 11 and 21. By being supported by rotation, the entire rotor 4 fixed to the rotation shaft 44 is held rotatably about the rotation shaft 44. Centrifugal cooling fans 47 and 48 are attached to the axial end surfaces of the pole cores 42 and 43. A pulley 5 is coupled to the front end of the rotating shaft 44 by a nut, and is driven to rotate by a vehicle engine (not shown). Further, a pair of slip rings 49 and 50 are provided at the rear end of the rotating shaft 44 located outside the rear side frame 2 and are electrically connected to the field winding 41.

  So-called electrical components such as the voltage regulator 6, the brush device 7, and the rectifying device 8 are fixed to the outer axial end surface of the rear side frame 2 by fixing means such as bolts. The voltage regulator 6 controls the output voltage of the vehicular AC generator 100 by adjusting the excitation current flowing through the field winding 41. The brush device 7 is for passing an exciting current from the rectifying device 8 to the field winding 41 of the rotor 4, and presses each of the slip rings 49 and 50 formed on the rotating shaft 44 of the rotor 4. Has a brush. The rectifier 8 rectifies a three-phase AC voltage, which is an output voltage of the three-phase stator winding 32, for example, and converts it into a DC output voltage.

  The rear cover 9 is made of a steel plate and covers and protects electrical components such as the voltage regulator 6, the brush device 7, and the rectifying device 8 that are attached to the outside of the rear side frame 2. The rear cover 9 is fastened and fixed to a bolt extending from the rear side frame 2 by a nut in a state where the rectifying device 8 is sandwiched.

  Incidentally, in the vehicle alternator 100 of the present embodiment, a resin cap 22 is provided in the rear-side rolling bearing box 21 for the purpose of preventing creep of the rear-side rolling bearing 46. FIG. 2 is a cross-sectional view showing a detailed structure of the rolling bearing box 21 on the rear side, the resin cap 22 and the brush device 7.

  As shown in FIG. 2, the brush device 7 includes a resin brush holder 71 in which the connection terminal 70 is embedded, a pair of brushes 72 and 73 that are in sliding contact with the slip rings 49 and 50, and the brushes 72 and 73. A pigtail 74 as a brush copper wire that electrically connects the connection terminal 70, a resin slip ring cover 75, and springs 76 and 77 that press the tips of the brushes 72 and 73 against the slip rings 49 and 50, respectively. It is configured to include. The brush holder 71 and the slip ring cover 75 form a resin surrounding member surrounding the brushes 72 and 73 and the slip rings 49 and 50.

  In the present embodiment, a part 71a of the brush holder 71 and a part 75a of the slip ring cover 75 form a cylinder part 90 as a whole, and this cylinder part is provided with a rotating shaft 44 formed on the rear frame 2. It protrudes toward the opening 30 for passing through.

  The resin cap 22 is a cylindrical member that is inserted between the rolling bearing 46 and the rolling bearing box 21 when the rear rolling bearing 46 is accommodated in the rolling bearing box 21, and a part thereof is the rear frame. 2 projecting as a cylindrical portion 92 on the opening 30 side. The resin cap 22 is used for the purpose of preventing the rolling bearing 46 from creeping.

  In the vicinity of the opening 30 of the rear frame 2, the two cylindrical portions 90 and 92 projecting from opposite sides overlap with each other along the rotation shaft 44 and are fitted to each other. In the example shown in FIG. 2, the cylindrical portion 92 is disposed on the inner diameter side of the cylindrical portion 90, but the cylindrical portion 92 may be disposed on the inner diameter side of the cylindrical portion 92.

  As described above, in the vehicle alternator 100 according to the present embodiment, the resin cap 22 is directly fitted to the brush holder 71 and the slip ring cover 75 serving as a resin surrounding member that covers the periphery of the slip rings 49 and 50. The airtightness of the space around the slip rings 49, 50 and the brushes 72, 73 can be improved without interposing another member between them, and the cost increase due to the increase in the number of parts can be prevented, and Waterproofness can be improved.

  In addition, since the respective distal end portions of the cylindrical portion 90 on the resin surrounding member side and the cylindrical portion 92 on the resin cap 22 side overlap in the axial direction, the connection portion between the resin surrounding member and the resin cap 22 Water exposure can be reliably prevented.

  In addition, this invention is not limited to the said embodiment, A various deformation | transformation implementation is possible within the range of the summary of this invention. For example, in the above-described embodiment, as shown in FIG. 3A, the cylindrical portion 90 is formed by both the part 71a of the brush holder 71 and the part 75a of the slip ring cover 75, but FIG. As shown in FIG. 3, a part 71a of only the brush holder 71 is extended in the circumferential direction to form the cylindrical portion 90 only by the brush holder 71, or only the slip ring cover 75 is formed as shown in FIG. The cylindrical portion 90 may be formed only by the slip ring cover 75 by extending a part 75a in the circumferential direction.

  Further, as another embodiment, as shown in FIG. 4, the distal end portions of the cylindrical portion 90 on the resin surrounding member side and the cylindrical portion 92 on the resin cap 22 side are overlapped along the axial direction so that the radial direction By providing a gap between the opposing surfaces and interposing an elastic member such as an O-ring 23 between the opposing surfaces, the airtightness of the space around the slip rings 49 and 50 and the brushes 72 and 73 is more reliably increased. Can do.

  Furthermore, the coefficient of thermal expansion of the resin on the small diameter side of the overlapping cylinder portion (in FIG. 4, the cylinder portion 92 may be changed to the small diameter side), but on the large diameter side (in FIG. 4, the cylinder portion). 90, but the cylindrical portion 92 may be on the larger diameter side), and the thermal expansion coefficient of the resin may be larger. Thereby, since the space | interval of the clearance gap between these cylinder parts 90 and 92 reduces by the difference in a thermal expansion coefficient at the time of the electric power generation of the vehicle alternator 100, the airtightness of an overlapping part can be ensured stably further. it can.

It is a figure showing the whole composition of the alternator for vehicles of one embodiment. It is sectional drawing which shows the detailed structure of a rolling bearing box and resin cap of a rear side, and a brush apparatus. It is a figure which shows the modification of the combination of a brush holder and a slip ring cover. It is a figure which shows other embodiment.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Front side frame 2 Rear side frame 3 Stator 4 Rotor 6 Voltage regulator 7 Brush device 8 Rectifier 9 Rear cover 11, 21 Rolling bearing box 22 Resin cap 23 O-ring 30 Opening 41 Field winding 42, 43 Pole core 44 Rotating shaft 45, 46 Rolling bearing 47, 48 Cooling fan 49, 50 Slip ring 71 Brush holder 72, 73 Brush 75 Slip ring cover 90, 92 Tube portion 100 AC generator for vehicle

Claims (5)

A slip ring provided on the rotating shaft of the rotor;
A resin surrounding member surrounding the slip ring and the surrounding space of the brush;
A bearing housing that houses a bearing that rotatably supports the rotor;
A resin cap inserted between the bearing and the bearing housing portion when housing the bearing;
The bearing housing portion and the resin surrounding member are disposed across an opening portion used for passing the rotating shaft formed in a frame,
An AC generator for a vehicle, wherein a part of the resin cap and a part of the resin surrounding member are fitted through the opening. In claim 1,
The part where the resin cap and the resin surrounding member are fitted has a cylindrical part extending in the rotational axis direction, and the tip portions of these two cylindrical parts overlap along the axial direction. A vehicle alternator, characterized in that A slip ring provided on the rotating shaft of the rotor;
A resin surrounding member surrounding the slip ring and the surrounding space of the brush;
A bearing housing that houses a bearing that rotatably supports the rotor;
A resin cap inserted between the bearing and the bearing housing portion when housing the bearing;
A cylindrical portion extending in the direction of the rotation axis while forming an opening used for passing the rotation shaft formed in the frame, wherein the bearing housing portion and the resin surrounding member are a part of the resin cap. Having a facing surface that overlaps in the rotational axis direction and forms a gap in the radial direction,
An AC generator for vehicles, wherein an elastic member is disposed between the facing surface and a part of the resin cap. In claim 3,
The tube portion is cylindrical,
An AC generator for a vehicle, wherein an O-ring as the elastic member is disposed in a groove provided on the outer periphery on the small diameter side or on the inner side on the large diameter side of a part of the opposing surface and the resin cap. . In any one of Claims 2-4,
The vehicular AC generator is characterized in that the coefficient of thermal expansion on the small diameter side of the opposing surface and part of the resin cap is larger than the coefficient of thermal expansion on the large diameter side.

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