Positioning member and voltage control device for vehicle alternator having the positioning member

A voltage control device for vehicle alternator has an IC chip as an electric component for controlling electric circuits, terminals connected electrically to the IC chip for controlling electric circuits, a resin case in which the terminals are formed by insert molding, and a terminal exposure portion of a hole shape, formed in a part of the resin case, corresponding to a positioning pin for positioning the terminals. A projection part as a positioning member of a wall shape is formed in the surroundings of the terminal exposure portion and on the surface of the resin case.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is related to and claims priority from Japanese Patent Application No. 2005-240518 filed on Aug. 23, 2005, the contents of which are hereby incorporated by reference.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates generally to a terminal positioning member and a voltage control device (as a regulator) for vehicle alternator having the positioning member capable of controlling an output voltage from a vehicle alternating current (AC) generator, in particular, relates to a positioning member for positioning terminals applicable to various vehicle devices such as a voltage control device for vehicle as a regulator.

2. Description of the Related Art

A vehicle alternator is equipped with a voltage control device, namely, a regulator for controlling the output voltage from the vehicle alternator. The regulator includes electric components therein such as mold integral circuits (ICs) that are sealed in a regulator protective case or a protective pack. In particular, electric terminals are positioned and then sealed in the regulator protective case by performing insert molding. A part of each electric terminal is protruded to the outside of the regulator protective case and is exposed to the outside atmosphere.

On performing the insert molding for sealing the electric terminals, it is necessary to fix the position of each electric terminal accurately at a specified position in the regulator protective case by using a positioning pin. The positioning pin is a positioning member.

FIG. 7is a diagram showing a concrete example of the configuration of a typical conventional regulator (as the voltage control device) andFIG. 8is a sectional diagram of the regulator along the line VII-VII in the configuration shown inFIG. 7.

As shown in thoseFIG. 7andFIG. 8, the terminals110are formed by the insert molding in the regulator protective case100. Because the insert molding for the electric terminals110is performed while the positioning pin (not shown) pushes a part of each electric terminal110through a positioning hole120that is also a positioning member. After the completion of the insert molding process, the positioning pin (not shown) is removed from the regulator protective case100. As a result, the hole120as the positioning member is remained in the cured regulator protective case100after the completion of the insert molding process and the positioning pin has already been removed from the regulator protective case100. Further, the part of each electric terminal110is exposed to the outside atmosphere through the bottom of the hole120. If rainwater or washing water invades into the hole120, the electric terminals110are corroded by the water because a current flows between the water at the bottom of the hole120, the electric terminal110, and other electric components made of metal, each of those is a different voltage potential from the voltage potential of the electric terminals110. Finally, the electric terminals are broken by corrosion. Thus, the presence of the hole120(as the positioning member) in the regulator protective case100is liable to electrolytic corrosion.

In order to prevent or avoid the occurrence of electrolytic corrosion by the invasion of the water into the hole120, there are well known manners such as the inserting mold method in which the hole120, through which a part of the electric terminal110is exposed to the outside atmosphere, is covered with insulation member.

The Japanese patent laid open publication No. JP-2000-61947 has disclosed such a conventional manner of positioning the electric terminals in a mold using insulating member while contacting the insulating member to the mold so as not to expose the electric terminal to the outside atmosphere, and, finally filling melted molding resin into the mold. This conventional method provides the regulator in which the electric terminals and the insulating member are inserted together in the regulator protective case.

However, because such a conventional method described above needs the additional process of setting the insulating member into the mold during the manufacturing process of the regulator, the manufacturing productivity thereby drops by the additional manufacturing step, and the manufacturing cost increases by adding the insulating member.

SUMMARY OF THE INVENTION

It is an object of the present invention to provide a positioning member and a voltage control device for vehicle alternator having the positioning member with highly manufacturing productivity and low manufacturing cost.

To achieve the above purposes, the present invention provides a positioning member to be used in positioning having a terminal exposure portion being a concave portion formed on a part of a case covering an electric device, and a projection part being a wall shape formed in the surrounding of the terminal exposure portion and on the surface of the case.

Further, the present invention also provide a voltage control device for vehicle alternator has electric components, terminals connected electrically to the electric components, a resin case in which the terminals are formed in insert molding, and positioning member.

The positioning member has a terminal exposure portion and a projection part. The terminal exposure portion is a concave portion formed on a part of the resin case, for use in positioning the terminals in the resin case. The projection part is a wall shape formed in the surrounding of the terminal exposure portion and on the surface of the resin case.

By forming the projection part of a wall shape in the surrounding of the terminal exposure portion as the positioning member, it is possible to prevent the invasion of water into the concave portion as the terminal exposure portion. It is thereby possible to eliminate additional components and any additional step of adding insulating member so that the terminals are not exposed. This can increase the manufacturing productivity and prevent the rise of manufacturing cost.

Further, it is preferred that the projection part as the positioning member and the resin case are formed in one body. This prevents the invasion of water into the terminal exposure portion by changing the more shape of the resin case mold, and prevents adding any additional parts.

Still further, it is preferred that the projection part has a cylindrical shape or a tube of a polygon shape. When the projection part has a cylindrical shape or a polygon shape, it is possible to cover the entire of the terminal exposure portion as the positioning member with the projection part and to prevent the invasion of water into the terminal exposure portion certainly.

Still furthermore, it is preferred that the projection part as the positioning member has a cylindrical shape having a notch at an angle of not more than 180 degrees has continuous plural planes formed in surrounding of the terminal exposure portion. It is thereby possible to prevent certainly the invasion of water into the terminal exposure portion along specified direction.

Still further, it is preferred that the vehicle alternator has the rear cover made of metal whose voltage potential is different from the voltage potential of the terminals and the projection part is protruded from the resin case toward the rear cover. It is thereby possible to prevent reaching water from the rear cover into the terminal exposure portion.

Moreover, it is preferred that one surface of the resin case on which the projection part as the positioning member is formed is arranged in a direction vertically to the ground under the vehicle alternator is mounted on a vehicle. It is thereby possible to prevent certainly the invasion of water, dropping along the direction from the ceiling to the ground, into the terminal exposure portion.

Still further, it is preferred that the projection part as the positioning member is formed at an upper portion of the terminal exposure portion in order to cover the terminal exposure portion along water flow onto the surface of the resin case under the vehicle alternator is mounted on a vehicle. It is thereby possible to prevent certainly the invasion of water flowing from a specified direction into the terminal exposure portion.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

Hereinafter, various embodiments of the present invention will be described with reference to the accompanying drawings. In the following description of the various embodiments, like reference characters or numerals designate like or equivalent component parts throughout the several diagrams.

Embodiment

A description will now be given of a voltage control device having a positioning member to be applied to a vehicle alternator according to the present invention with reference to drawings. However, the concept of the present invention can be applied to various electric devices such as an alternating current motor such as a stator and other electric devices to be incorporated in movable bodies such as a vehicle.

FIG. 1is a sectional diagram showing the entire configuration of a vehicle alternator (AC generator) equipped with a regulator (as the voltage control device) having an improved positioning member according to an embodiment of the present invention.

As shown inFIG. 1, the vehicle alternator comprises a front frame1, a rear frame2, a stator4, a rotor10, a rectifier unit24, a regulator25(as the voltage control device), a brush unit26, and a rear cover27.

Both the front frame1and the rear frame2have a bracket shape and fastened to each other by plural bolts3while contacting opening parts of both the front frame1and the rear frame2to each other. The stator4is fixed to the inner peripheral wall of the front frame1. The front frame1and a cylindrical bearing box7are assembled in one body. A bearing box8made of iron is attached to the rear frame2by knurling bolts9.

The stator4has a stator core5and stator windings6. The rotor10has field windings11, pole cores12and13, a shaft14, and the like. The rotor10rotates freely while supported by a pair of bearings15and16that are fixed to bearing boxes7and8.

The cooling fans17and18are attached to the end surface of each of the pole cores12and13in its axis direction. Blades of the cooling fan17are inclined to the rotational direction of the rotor10in order to generate cooling wind to the field windings11.

A pulley19is connected and attached to the front end of the shaft14by nuts20and driven by an engine mounted on a vehicle through belts. The engine, the vehicle, and the belts are omitted from the drawings. A pair of slip rings21and22is mounted on the rear end of the shaft14that is positioned at the outer peripheral of the rear frame2and connected electrically to the field windings11through an electrical conductor23.

The electrical components such as the rectifier unit24as the rectifier device, the regulator25as the voltage control device, and the brush unit26are fixed along the axis direction to the end surface of the outer peripheral part of the rear frame2by bolts9as fixing means. The rectifier unit24rectifies the three phase alternate current (AC) voltage, which is generated from the three phase stator windings6, and the direct current (DC) voltage is acquired. The regulator25as the voltage control device controls the output voltage of the vehicle alternator by regulating the exciting current which flows to the field windings11.

Through the brush unit26, the exciting current flows from the rectifier unit24to the field windings11of the rotor10. The brush unit26has brushes that push slip rings21and22formed on the shaft14of the rotor10.

The rear cover27is made of metal, and covers and protects the electrical components such as the rectifier unit24, the regulator25, the brush unit26, and the like. Those electric components are mounted on the outer peripheral part of the rear frame2.

The rear cover27is fixed to the rear frame2by the nuts28and the bolts9extending form the rear frame2. The rectifier unit24is fixed between the rear frame2and the rear cover27. The rear cover27has cooling-wind introduction openings of concentric circle shape through which the cooling wind flows in and out.

Next, a description will now be given of the configuration of the regulator25having the improved positioning member according to the embodiment in detail.

FIG. 2is a plan view of a configuration of the regulator25having the improved positioning member, to be mounted on the vehicle alternator shown inFIG. 1.FIG. 3is a sectional view of a projection part as the positioning member formed in the regulator25along the line III-III shown inFIG. 2.

The regulator25as the voltage control device according to the embodiment of the present invention has a control IC chip251as an electric component, the three terminals252connected to the control IC chip251, and a sealing resin case253in which the terminals252are formed by the insert molding. The control IC chip251is sealed in the resin case253with a sealing resin254such as silicon in order to protect it from water.

The resin case253has a connector section255through which the IC chip251is electrically connected to vehicle connectors (omitted from drawings). A part of the terminals252formed by the insert molding is exposed to the outer atmosphere at the connector section255and the IC chip251is electrically connected to the connector section255through the terminals252.

A part of the resin case253has a terminal exposure portion256(as the positioning member) of a concave shape or a hole shape corresponding to a positioning pin (not shown) for positioning the terminals252in the resin case253. The positioning for the terminals252in the resin case253is carried out by molding the resin case253by the insert molding for the terminals252contacted to the terminals252to the front part of the positioning pin (not shown).

A wall-shaped projection part257(as the positioning member) is formed at the outer surface of the resin case253and at the peripheral portion of the terminal exposure portion256. The projection part257and the resin case253are formed in one body. The projection part257is formed as it projects from the resin case253to the rear cover27. The rear cover27is a ground voltage potential level, and on the contrary, the terminals252have different voltages corresponding to the battery voltage level based on various control signals. In the normal operation, those voltages at the terminals252have different voltage potentials. On mounting on a vehicle, one end surface of the resin case253having the projection part257in the regulator25is placed approximately vertical to the ground surface.

Thus, it is possible to prevent the invasion of water into the terminal exposure portion256(as the positioning member) by forming the projection part257(as the positioning member) of a wall shape formed in the surrounding of the terminal exposure portion256, and the terminal exposure portion256is formed in the resin case253of the regulator25. Accordingly, it can be eliminate the manufacturing step of adding insulating member and also eliminate the necessity of additional parts such as the insulating member so that the terminals252are not exposed to the outer atmosphere, in order to prevent any occurrence of a galvanic corrosion and breaking wire of the terminals252by the invasion of rainwater or washing water accumulated between the terminals252and components having a voltage potential different from the voltage potential of the terminals252exposed through the terminal exposure portion256. This can increase the manufacturing productivity and prevent the rise of manufacturing cost of the voltage control device for vehicle alternator.

In addition, when both the projection part257(as the positioning member) and the resin case253are formed in one body, it is possible to prevent the invasion of water into the terminal exposure portion256(as the positioning member) by changing the mere shape of the resin case253. This needs no additional components.

Furthermore, when the projection part257(as the positioning member) has a cylindrical shape, the entire peripheral part of the terminal exposure portion256is covered with the projection part257and this can prevent the invasion of water into the terminal exposure portion256certainly.

Furthermore, when a part of the projection part257is projected from the resin case253toward the rear cover27made of metal, it is possible to prevent water reaching into the terminal exposure portion256from the rear cover27. In particular, when the regulator having the terminal exposure portion256having the projection part257is mounted on a vehicle alternator incorporated in a vehicle, because one surface of the resin case253having the projection part257is faced in approximate vertical direction to the ground, it is possible to prevent the occurrence of the invasion of water dropping from the ceiling of the vehicle to the ground certainly.

The present invention is not limited by the embodiment described above, it is possible to provide various modified embodiments within the scope of the concept of the present invention. For example, although the above embodiment provides the projection part257(as the positioning member) of a cylindrical shape, it is possible to form it with other shape.

FIG. 4toFIG. 6are diagrams showing various configuration of modified projection part257. That is, it is possible to form the projection part257(as the positioning member) with a tube of a polygon shape.FIG. 4shows projection part257of a tube of a square shape.

The projection part257formed with a tube of a polygon shape can prevent the invasion of water into the terminal exposure portion256certainly because the entire peripheral part of the terminal exposure portion256can be covered with the projection part257of a tube of a polygon shape, just like the projection part257with a cylindrical shape.

Furthermore, as shown inFIG. 5, it is possible to form the projection part257with a cylindrical shape having a notch at an angle of 180 degrees or less. Still furthermore, as shown inFIG. 6, it is possible to form the projection part257with continuous plural planes around the terminal exposure portion256. This can prevent certainly the invasion of water into the terminal exposure portion256in specified direction.

In particular, the projection part257having the configuration shown inFIG. 5orFIG. 6can cover at least the upper part of the terminal exposure portion256in water dropping direction to the surface of the resin case253. This configuration can prevent the invasion of water flowing, in one direction, into the terminal exposure portion256certainly.