Abstract:
Provided is a vehicle AC generator for improving working efficiency in assembly, allowing a reduction in the number of components, and the like. The vehicle AC generator includes: a rectifier for rectifying an AC generated by a stator coil into a DC; and a regulator for regulating an AC voltage generated by the stator coil, in which: the regulator includes: a regulator holder; a regulator main body provided inside the regulator holder, the regulator main body being for regulating the AC voltage; a capacitor provided inside the regulator holder, the capacitor being for absorbing a noise generated when the AC is rectified into the DC by the rectifier; and an insulating resin material filling the regulator holder so as to fix the regulator main body and the capacitor.

Description:
BACKGROUND OF THE INVENTION 
     1. Field of the Invention 
     The present invention relates to a vehicle AC generator including a rectifier for rectifying an AC generated by a stator coil into a DC and a regulator for regulating an AC voltage generated by the stator coil. 
     2. Description of the Related Art 
     Conventionally, the following vehicle AC generator is known. The vehicle AC generator includes a regulator case and a capacitor case. The regulator case houses a regulator board for voltage regulation therein. The capacitor case is superposed on an opening of the regulator case in a planar manner and houses a capacitor element therein. The capacitor case and the regulator case are both fixed to a bracket by using bolts (for example, see JP 05-219704 A). 
     However, the vehicle AC generator having the aforementioned structure has the following problems. The capacitor case is superposed on the regulator case while bolt through-holes of the capacitor case and the regulator case are brought into alignment. Then, the bolts are caused to pass through the plurality of bolt through-holes being in alignment to screw the regulator case and the capacitor case together in an integrated manner. Therefore, an assembly operation becomes disadvantageously complicated. 
     Moreover, two components, that is, the regulator case and the capacitor case, are required. Therefore, the number of components is correspondingly increased. 
     In addition, in the conventional vehicle AC generator, the capacitor case is filled with an epoxy resin which is then solidified, thereby firmly fixing the capacitor element in the capacitor case. For each of electronic components exposed on the regulator board inside the regulator case, however, for example, a welded portion of a terminal of an electronic component is likely to be damaged due to a vibration or the like. 
     SUMMARY OF THE INVENTION 
     The present invention has been made to solve the problems described above, and has an object to provide a vehicle AC generator for improving working efficiency in assembly and allowing a reduction in the number of components, which includes a regulator with improved reliability obtained by protecting a regulator main body and a capacitor with an insulating resin material. 
     According to the present invention includes:
         a rectifier for rectifying an AC generated by a stator coil into a DC; and   a regulator for regulating an AC voltage generated by the stator coil,   wherein the regulator includes:
           a regulator holder;   a regulator main body provided inside the regulator holder, the regulator main body being for regulating the AC voltage;   a capacitor provided inside the regulator holder, the capacitor being for absorbing a noise generated when the AC is rectified into the DC by the rectifier; and   an insulating resin material filling the regulator holder so as to fix the regulator main body and the capacitor.   
               

     According to the vehicle AC generator of the present invention, the regulator main body and the capacitor are fixed inside the regulator holder with the insulating resin material to be housed therein. As a result, the working efficiency in assembly is improved, while the number of components can be reduced. Further, the reliability of the regulator main body and the capacitor is improved. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       In the accompanying drawings: 
         FIG. 1  is a sectional side view illustrating a vehicle AC generator according to a first embodiment of the present invention; 
         FIG. 2  is an electric circuit diagram illustrating the vehicle AC generator of  FIG. 1 ; 
         FIG. 3  is a front view illustrating a regulator of  FIG. 1  (insulating resin material is omitted here); 
         FIG. 4  is a sectional view illustrating the regulator taken along the line IV-IV of  FIG. 3 ; 
         FIG. 5  is a front view illustrating a regulator holder of the regulator of  FIG. 3 ; 
         FIG. 6  is a sectional view illustrating the regulator holder taken along the line VI-VI of  FIG. 5 ; 
         FIG. 7  is a plan view illustrating an IC regulator main body of  FIG. 4 ; 
         FIG. 8  is a side view illustrating the IC regulator main body of  FIG. 7 ; 
         FIG. 9  is a plan view illustrating a heat sink of  FIG. 4 ; 
         FIG. 10  is a side view illustrating the heat sink of  FIG. 9 ; 
         FIG. 11  is a sectional side view of a principal part of the vehicle AC generator, illustrating a step of assembling the vehicle AC generator of  FIG. 1 ; 
         FIG. 12  is a sectional side view of the principal part of the vehicle AC generator, illustrating another step of assembling the vehicle AC generator of  FIG. 1 ; 
         FIG. 13  is a sectional side view of the principal part of the vehicle AC generator, illustrating a further step of assembling the vehicle AC generator of  FIG. 1 ; 
         FIG. 14  is a front view illustrating a regulator of a vehicle AC generator according to a second embodiment of the present invention (insulating resin material is omitted here); 
         FIG. 15  is a sectional view illustrating the regulator taken along the line XV-XV of  FIG. 14 ; and 
         FIG. 16  is a front view illustrating a regulator holder of a regulator according to a modified example of the vehicle AC generator of the present invention. 
     
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
     Hereinafter, embodiments of the present invention are described referring to the accompanying drawings. In each of the drawings, the same or equivalent parts and components are denoted by the same reference symbols. 
     First Embodiment 
       FIG. 1  is a sectional side view illustrating a vehicle AC generator according to a first embodiment of the present invention,  FIG. 2  is an electric circuit diagram of the vehicle AC generator of  FIG. 1 ,  FIG. 3  is a front view illustrating a regulator  13  of  FIG. 1 , and  FIG. 4  is a sectional view illustrating the regulator  13  taken along the line IV-IV of  FIG. 3 . In  FIGS. 3 and 4 , the illustration of an insulating resin material is omitted. 
     The vehicle AC generator (hereinafter, referred to simply as a “generator”) includes a front bracket  1 , a rear bracket  2 , a shaft  4 , a claw-pole type rotor  5 , a front fan  6 , a rear fan  7 , a slip ring  8 , a pair of brushes  9 , a stator core  10 , a stator coil  11 , a rectifier  12 , a regulator  13 , and a heat sink  14 . The shaft  4  is provided inside the front bracket  1  and the rear bracket  2 . A pulley  3  is mounted to one end of the shaft  4 . The rotor  5  is mounted to the shaft  4 . The front fan  6  is mounted on the front bracket  1  side of the rotor  5 , whereas the rear fan  7  is mounted on the rear bracket  2  side of the rotor  5 . The slip ring  8  is mounted to the shaft  4  and supplies a current to the rotor  5 . The pair of brushes  9  slide against the slip ring  8 . The stator core  10  is fixed to the front bracket  1  and the rear bracket  2 . The stator coil  11  is obtained by winding a conductor around the stator core  10 . The rectifier  12  is electrically connected to the stator coil  11  to rectify an AC generated by the stator coil  11  into a DC. The regulator  13  regulates an AC voltage generated by the stator coil  11 . The heat sink  14 , which is provided for cooling the regulator  13 , is mounted to the regulator  13 . 
     The regulator  13  includes a regulator holder  15  illustrated in  FIGS. 5 and 6 , an IC regulator main body  16  illustrated in  FIGS. 7 and 8 , a capacitor  50  for noise prevention, and an insulating resin material (not shown). The capacitor  50  absorbs a high-frequency noise which adversely affects a radio wave, which is generated when the AC is rectified into the DC by the rectifier  12 . The insulating resin material fills an internal space of the regulator holder  15  to fix the IC regulator main body  16  and the capacitor  50  therein. 
     The IC regulator main body  16  corresponding to a regulator main body includes an IC chip portion  31  and a plurality of terminals  25 . The IC chip portion  31  is integrally formed by molding. The plurality of terminals  25  extend unidirectionally from the IC chip portion  31 . 
     The regulator holder  15 , which is integrated with an insert terminal  17  by insert-molding, includes a pair of brush holes  18 , a mount surface  19 , projecting portions  20 , and a connector portion  21 . The brushes  9  are inserted into the pair of brush holes  18 . On the mount surface  19 , the IC regulator main body  16  is mounted. The projecting portions  20  are fitted into concave portions (not shown) of the IC regulator main body  16 . The connector portion  21  is connected to a vehicle connector (not shown). 
     The regulator holder  15  also includes an enclosure portion  22 . The enclosure portion  22  surrounds an entire periphery of the mount surface  19  and has a level-difference portion  23 . The level-difference portion  23  has a groove portion  24  formed thereon to extend over an entire periphery thereof. In addition, the heat sink  14  illustrated in  FIGS. 9 and 10  is placed on the level-difference portion  23 . 
     The insert terminal  17  includes a main-body connecting portion  17   a , a connector connecting portion (not shown), a rectifier connecting portion  17   b , a rear-bracket connecting portion  17   c , and a capacitor connecting portion  17   d  (see  FIG. 4 ). The main-body connecting portion  17   a  is exposed on the mount surface  19  and is electrically connected to the terminals  25  of the IC regulator main body  16 . The connector connecting portion is exposed inside the connector portion  21 . The rectifier connecting portion  17   b  is electrically connected to the rectifier  12 . The rear-bracket connecting portion  17   c  is electrically connected to the rear bracket  2 . The capacitor connecting portion  17   d  is electrically connected to a pair of terminals  51  of the capacitor  50 . 
     In  FIG. 2 , a stator  60  and winding portions  61  are illustrated. The stator  60  includes the stator core  10  and the stator coil  11 . The stator coil  11  is constituted by two three-phase AC windings, each being obtained by connecting the three winding portions  61  in a three-phase Y-configuration. A battery  26  and an electric load  62  are also illustrated in  FIG. 2 . 
     Although not illustrated in  FIG. 2 , the IC regulator main body  16  is electrically connected to an external on-vehicle device or the like through the terminals  25  in this embodiment. 
     In the generator having the aforementioned structure, the current is supplied from the battery  26  through the brushes  9  and the slip ring  8  to the rotor coil  27  of the rotor  5  to generate a magnetic flux. As a result, claw-like magnetic poles  28  of the rotor  5  are magnetized to an N-pole, whereas claw-like magnetic poles  29  of the rotor  5  are magnetized to an S-pole. 
     On the other hand, the pulley  3  is driven by an engine (not shown) and the rotor  5  is rotated by the shaft  4 , and hence a rotating magnetic field is applied to the stator core  10 . As a result, an electromotive force is generated in the stator coil  11 . 
     The degree of the AC electromotive force is regulated by the regulator  13  which regulates the current flowing through the rotor  5 . 
     After the AC generated by the AC electromotive force is rectified into the DC through the rectifier  12 , the battery  26  is charged with the obtained DC. 
     The rectified current, that is, the DC obtained by the rectification flows through the capacitor  50 . The capacitor  50  suppresses a steep commutating surge voltage generated at the time of rectification to absorb the high-frequency noise which adversely affects the radio wave. 
     Next, a procedure of fabrication of the regulator  13  of the generator having the aforementioned structure is described. 
     First, the concave portions of the IC regulator main body  16  are fitted to the projecting portions  20  provided on the mount surface  19  of the regulator holder  15  to place the IC regulator main body  16  on the mount surface  19 . The terminals  25  of the IC regulator main body  16  are superposed on the main-body connecting portion  17   a  (see  FIG. 11 ) to be fixed thereto by welding. 
     Next, a thermally conductive material is applied to a heat-generating portion  30  of the IC chip portion  31  of the IC regulator main body  16 . The heat sink  14  is placed on the level-difference portion  23  of the enclosure portion  22  of the regulator holder  15  (see  FIG. 12 ). Then, a distal end A of the enclosure portion  22  is bent inward to fix the heat sink  14  to the regulator holder  15 . 
     After that, the regulator holder  15  is turned upside down (see  FIG. 13 ). The terminals  51  of the capacitor  50  are bonded to the capacitor connecting portion  17   d  of the insert terminal  17  by welding (see  FIG. 4 ). 
     Finally, the internal space of the regulator holder  15  is filled with an epoxy insulating resin material to fix the IC regulator main body  16  and the capacitor  50  therein. 
     The IC regulator main body  16  side and the capacitor  50  side of the regulator holder  15  are in communication with each other through the internal space of the regulator holder  15 . Therefore, by injecting the insulating resin material from a part of an opening of the regulator holder  15 , the entire internal space of the regulator holder  15  is filled with the insulating resin material. 
     According to the generator of this embodiment, the IC regulator main body  16  and the capacitor  50  are housed in the same regulator holder  15 . Thus, the number of components is reduced. 
     Moreover, the IC regulator main body  16  and the capacitor  50  are simultaneously fixed with the insulating resin material which is injected from the opening of the regulator holder  15  to fill the internal space thereof. Thus, a fabrication time is reduced, while the IC regulator main body  16  and the capacitor  50  are protected with the insulating resin material to improve reliability. 
     Further, the regulator holder  15  includes the mount surface  19  on which the IC regulator main body  16  is mounted and the enclosure portion  22  which surrounds the IC regulator main body  16 . The heat sink  14  which is in surface contact with the IC regulator main body  16  mounted on the mount surface  19  inside the enclosure portion  22  is fixed by the inwardly bent distal end A of the enclosure portion  22 . 
     Therefore, the IC regulator main body  16  can be turned upside down before the IC regulator main body  16  and the heat sink  14  are connected by curing of the thermally conductive material which is present between the heat-generating portion  30  of the IC regulator main body  16  and the heat sink  14 . By subsequently filling the regulator holder  15  with the insulating resin material, the thermally conductive material and the insulating resin material can be cured at the same time. As a result, the fabrication time can be further reduced. 
     Further, the heat sink  14  has not only a heat-releasing function but also a function as a bottom lid when the insulating resin material is injected into the internal space of the regulator holder  15 . 
     Moreover, an area in which the terminals  25  of the IC regulator main body  16  are welded to the main-body connecting portion  17   a  of the insert terminal  17  (the area is also referred to as a “welding area”) is separate away from a surface of the heat sink  14 , which abuts against the IC regulator main body  16 , as illustrated in  FIG. 13 . In addition, the entire periphery of the welding area is covered with the insulating resin material. Thus, the welding area is further prevented from being damaged. 
     Further, the enclosure portion  22  of the regulator holder  15  has the level-difference portion  23  on which the heat sink  14  is placed. Further, the groove portion  24  is formed in the level-difference portion  23  along the periphery of the heat sink  14 . Thus, the insulating resin material filling the internal space of the regulator holder  15  hardly flows out from the regulator holder  15 . 
     Second Embodiment 
       FIG. 14  is a front view illustrating a regulator  13 A of the generator according to a second embodiment of the present invention, and  FIG. 15  is a sectional view illustrating the regulator  13 A taken along the line XV-XV of  FIG. 14 . In  FIGS. 14 and 15 , the illustration of the insulating resin material is omitted. 
     In the regulator  13  of the first embodiment, the area in which the terminals  25  of the IC regulator main body  16  and the main-body connecting portion  17   a  of the insert terminal  17  are welded to each other and an area in which the two terminals  51  of the capacitor  50  and the capacitor connecting portion  17   d  of the insert terminal  17  are welded to each other are separated away from each other with the brush holes  18  being interposed therebetween, as illustrated in  FIG. 4 . 
     On the other hand, in the regulator  13 A of the second embodiment, the area in which the terminals  25  of the IC regulator main body  16  and the main-body connecting portion  17   a  of the insert terminal  17  are welded to each other and the area in which the pair of terminals  51  of the capacitor  50  and the capacitor connecting portion  17   d  of the insert terminal  17  are welded to each other are situated on the same side to be close to each other as illustrated in  FIG. 15 . 
     The remaining structure is the same as that of the generator of the first embodiment. 
     In comparison with the first embodiment, an internal space of a regulator holder  15 A is small in this embodiment. Correspondingly, a smaller amount of the insulating resin material is sufficient to fill the internal space of the regulator holder  15 A. Thus, the insulating resin material injected from an opening of the regulator holder  15 A to fill the internal space thereof is cured within a correspondingly shorter period of time, thereby further reducing the fabrication time. 
     Although the regulators  13  and  13 A of the generator, each including the brushes  9 , have been described in the first and second embodiments, the present invention is also applicable to a regulator of a brushless generator. 
       FIG. 16  is a front view illustrating a regulator holder  15 B of the regulator of the brushless generator. 
     Although the case where the mold-packaged IC regulator main body  16  obtained by integrally molding a voltage control circuit, an external circuit, and the like is used as the regulator main body has been described in each of the embodiments, it is apparent that the application of the present invention is not limited thereto. The present invention is also applicable to a regulator main body including, for example, an electronic circuit of a hybrid IC formed on one surface of a board.