Patent Abstract:
An AC generator for a vehicle has a cover and a connector to be connected with an end connector from a vehicle mounted circuit. The connector and the end connector have a lock mechanism using a lock portion and a lever. The cover has an opening for providing a visual accessibility on the lock mechanism. The opening allows to check the lock portion on the connector after the cover is installed and the lever on the end connector even after the end connector is connected with the connector.

Full Description:
CROSS REFERENCE TO RELATED APPLICATION 
     This application is based on Japanese Patent Application No. 2000-75301 filed on Mar. 17, 2000, No. 2000-127389 filed on Apr. 27, 2000 and No. 2000-371318 filed on Dec. 6, 2000, the contents of which are incorporated herein by reference. 
     BACKGROUND OF THE INVENTION 
     1. Field of the Invention 
     The present invention relates to an AC generator for a vehicle such as a passenger vehicle and a truck. Specifically, the present invention prefers to an alternator for a vehicle. 
     2. Description of Related Art 
     FIG. 5 shows a conventional arrangement of an alternator for a vehicle. The alternator  1  has a frame  4  supporting a rotor and a stator. The frame  4  also supports a rectifier  5  and regulator  8  on a rear side of the alternator  1 . 
     The regulator  8  regulates an output voltage of the alternator by controlling a field current. The regulator  8  has a case  81 , an electric circuit (not shown), and an axially protruding and axially opening connector  82  integrally formed with the case  81 . The connector  82  is connectable with an end connector (not shown) extending from a vehicle-mounted circuit. The connector  82  and the end connector have a lock mechanism. The connector  82  has a lock portion  83  disposed on an outside wall of the connector  82 . The lock portion  83  is a wedge shaped projection on which a resilient arm portion on the end connector is locked when the end connector is connected with the connector  82 . 
     The rectifier  5  and the regulator  8  are protected and covered with a cover  6  mounted on the frame  4  by stud bolts  10  and nuts  9 . The cover  6  has a window  61  for permitting a connection between the connector  82  and the end connector. The cover  6  also has a plurality of cooling windows  63 . 
     SUMMARY OF THE INVENTION 
     The cover  6  hides the lock portion  83  from view. Therefore, it is difficult to check the lock portion after the cover  6  is fixed. Moreover, at an assembling line of the vehicle or a service shop, a worker cannot see a locking condition of the lock mechanism during a connecting process and after the end connector is connected with the connector. 
     The present invention addresses these drawbacks by providing an improved arrangement of an AC generator for vehicle. 
     It is therefore an object of this invention to provide an AC generator for vehicle which provides an easy and secure connection between a connector and an end connector. 
     It is a further object of this invention to provide an AC generator for vehicle which permits a check of a lock mechanism of a connector. 
     According to a first aspect of the present invention, a cover provides a visual accessibility on a lock portion of a connector on an AC generator for vehicle. The lock portion can be checked visually. 
     According to a second aspect of the present invention, a cover has an additional opening area. The additional opening area provides a visual accessibility on a lock portion. The additional opening may be provided by an enlarged opening or an additional independent opening. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     Other features and advantages of the present invention will be appreciated, as well as methods of operation and the function of the related parts, from a study of the following detailed description, the appended claims, and the drawings, all of which form a part of this application. In the drawings: 
     FIG. 1 is a sectional view of an alternator for a vehicle according to a first embodiment of the present invention; 
     FIG. 2 is a partial sectional view of an alternator showing a connector and a cover according to a second embodiment of the present invention; 
     FIG. 3 is a plan view from rear side of the alternator according to the second embodiment of the present invention; 
     FIG. 4 is a partial sectional view of the alternator showing the connector, the cover and an end connector according to the second embodiment of the present invention; and 
     FIG. 5 is a sectional view of an alternator according to a prior art. 
    
    
     DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS 
     The present invention applied to an alternator for vehicle shown in FIG.  1 . 
     The alternator  1  has a stator  2 , a rotor  3  and a frame  4 . The frame  4  supports a rectifier  5 , a cover  6  and a regulator  8  on a rear side by a plurality of through bolts  10  and nuts  9 . 
     The stator  2  is supported and fixed on the frame  4 . The stator  2  has a stator winding  21  and a stator core  22 . The stator winding  21  is connected with the rectifier  5  by a connecting lead  23  passing through an insulating tube  24  inserted into a hole formed on a rear side wall of the frame  4 . 
     The rotor  3  is rotatably supported on the frame  4 . The rotor  3  has a shaft  31 , a Lundel type iron core  32  formed by a combined pair of pole cores, a pair of slip rings  33  and  34 , a pair of cooling fans  35  and  36  and a field coil  37 . The cooling fans  35  and  36  are centrifugal fans. The cooling fans  35  and  36  are fixed on both sides of the core  32  by a spot welding or the like. A pulley  7  for receiving a rotating force from an engine is fixed on the shaft  31 . The frame  4  has a plurality of air inlets  41  and air outlets  42  for the cooling fans  35  and  36 . 
     The rectifier  5  has a negative side fin  53 , a positive side fin  54  and a terminal holder  55  integrally formed with the insulating tube  24 . The negative side fin  53  and a positive side fin  54  each has a plurality of rectifying elements. The terminal holder  55  holds a plurality of terminals connecting with the stator winding  21  and the rectifying elements. 
     The regulator  8  has a case  81 , a connector  82  and a lock portion  83  as a part of a lock mechanism. The case  81 , the connector  82  and the lock portion  83  are formed integrally by a resin. The connector  82  has a plurality of connector pins as a terminal of a circuit unit  84 . The case  81  is a member covered with the cover  6 . 
     The regulator  8  is located on a radial outside to a brush unit which has a pair of brushes for the slip rings  33  and  34 . The regulator  8  and the brush unit are lined up on a radial direction and mounted on the frame  4 . The regulator  8  is apart from the brush unit to provide a cooling air passage between them. 
     The case  81  accommodates the circuit unit  84  which has an integrated circuit and discrete electric elements. The circuit unit  84  may be an integrated circuit or a conventional printed circuit board. The case  81  may contain only a transistor for switching a field current supplied through the brushes and the slip rings  33  and  34  to the field winding  37 . 
     The connector  82  extends from a radial outside portion of the case  81 . The connector  82  extends to reach an outside of the cover  6 . The connector  82  extends and opens axially. 
     The lock portion  83  is located on a radial outside wall of the case  81  and the connector  82 . The lock portion  83  is a wedge shaped projection. The lock portion  83  provides a slope  830 , a step  832  and both side surfaces. The slope  830  is elevated as it is distanced from an axial end of the connector  82  to receive a resilient arm of an end connector from the vehicle. The end connector is disposed on an end of a wire extended from an electric circuit mounted on the vehicle. The resilient arm is a part of the lock mechanism for locking the connectors. The end connector and the resilient arm may form as shown in FIG.  4 . The step  832  locks the resilient arm when the resilient arm reaches to the step  832 . 
     The cover  6  protects electric components, the rectifier  5 , the regulator  8  and the brush unit, mounted on a rear side of the alternator. The cover  6  is shaped as a dish with rounded edge except for a portion in which the regulator  8  is accommodated. The cover  6  provides a flat wall on a radial outside to the regulator  8 . The cover  6  defines a plurality of openings, a first opening  61  for the connector  82 , a second opening for the lock portion  62  and a plurality of third openings  63  for cooling air. 
     The cover  6  is made of resin, but the cover  6  may made of metal. Further, the cover  6  may be provided by the frame  4  since the frame  4  may protects the electric components when they are installed inside the frame  4  as well as the cover  6 . In this arrangement, the openings are formed on the frame  4 . 
     The first opening  61  is located on an axial wall of the cover. The first opening  61  has an opening area slightly larger than the connector  82  to pass the connector  82  through and to receive the end connector. However, the first opening  61  is not enough to provide a sufficient opening area to permit a sufficient visual accessibility on the lock portion  83  after the connector  82  is located in the first opening  61 . 
     The second opening  62  is located on a radial outside wall of the cover  6 . The second opening  62  directly faces at least one surface of the lock portion  83 . The second opening  62  provides an additional opening area faces perpendicular to an operating direction in which the end connector is operated to connect and disconnect with the connector  82 . Therefore, the lock portion  83  is visually accessible from radial outside of the alternator through an opening area of the second opening  62 . Further, the lock portions and the lock mechanism, the lock portion  83  and the resilient arm, are visually accessible even after the end connector is connected with the connector  82 . 
     It is preferable that the second opening  62  is located on an upper side when the alternator  1  is mounted on an engine of the vehicle. The connector  82  may extends in a radial direction of the alternator and opens toward a radial outside. Further, the first opening  61  and the second opening  62  may be connected. It is possible to provide an additional opening area by enlarging the first opening  61  beyond the opening area required to receive the connector  82  and the end connector. The openings defined by the cover  6  may reach an outside edge of the cover  6 . The cover  6  may be made of transparent material to provide the visual accessibility. 
     The second opening  62  also acts as a cooling air inlet as well as the third opening  63  and a remaining area of the first opening  61  around the connector  82 . An opening area of the second opening  62  is larger than the remaining area of the first opening  61 . An opening area of the second opening  62  is larger than each opening area of the third openings  63 . The second opening  62  is wide enough in both length and breadth and has a sufficient opening area to permit a visual check of the lock portion  83  and the resilient arm. The third openings  63  are slits which are narrower than the second opening  62 . The second opening  62 . 
     In this embodiment, the lock portion  83  can be visually checked even after the cover  6  is installed. Further, the resilient arm of the end connector can be visually checked even after the end connector is connected with the connector  82 . 
     FIG. 2 shows a second embodiment of the present invention. The cover  6  is formed as a dish with a curved edge defined by an average radius R. The average radius R is larger than a radial length L of the connector  82 . The openings  61  and  62  are integrally formed into a unitary opening. The unitary opening located over an axial wall and a radial wall provides both of opening area as the first opening  61  and the second opening  62 . The opening is located at a boundary of the axial wall and the radial wall. Therefore, the lock portion  83  is exposed to an outside of the cover  6 . 
     The lock portion  83  maybe located on a circumferential side-wall of the connector  82  as shown in FIG.  3 . The opening opens toward a radial outside and faces a side surface of the lock portion  83 . The lock portion  83  is still visible from a radial outside. 
     FIG. 4 shows the end connector  11 . The end connector  11  has a lever  101  as the resilient arm. The lever  101  has a hole  102  to receive the lock portion  83  when the end connector is operated to connect with the connector  82  properly. The lever  101  releases the lock portion  83  when the lever  101  is manually operated to lift an end of the lever  101 . 
     As shown in FIG. 4, a lock mechanism having the lock portion  83  and the lever  101  are entirely exposed to a radial outside. Therefore, the lock mechanism of the connectors  82  and  11  are visible from a radial outside of the alternator. 
     Although the present invention has been described in connection with the preferred embodiments thereof with reference to the accompanying drawings, it is to be noted that various changes and modifications will be apparent to those skilled in the art. Such changes and modifications are to be understood as being included within the scope of the present invention as defined in the appended claims.

Technology Classification (CPC): 8