JP4579392B2 - Vehicle alternator - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a vehicle alternator, and in particular, is efficient while reducing the size of both a plus-side heat sink and a minus-side heat sink in which a plurality of plus-side diodes and a plurality of minus-side diodes for rectifying the generated voltage of a stator coil are mounted. The present invention relates to a vehicular AC generator that is well cooled and has a good cooling air introduction structure for a rear cover that takes in cooling air and a structure for attaching a rear cover to a rear bracket.
[0002]
[Prior art]
An electric circuit as shown in FIG. 11 is generally used for an AC generator for a vehicle mounted on an automobile such as a truck, a bus, and a passenger car in order to output the DC voltage.
[0003]
In the figure, an alternator 11 is a brushless alternator mounted on an automobile, and includes a stator 13 having three-phase power generation coils 12A, 12B, and 12C, and four positive diodes 14P, 15P, 16P, The positive side heat sink 18P and the anodes of the four negative side diodes 14M, 15M, 16M, and 17M are electrically connected in parallel and grounded and attached to each cathode of 17P. A negative heat sink 18M, a field coil 19, and a regulator 20.
[0004]
The plus side diodes 14P to 17P are connected to the output terminal 21 of the alternator 11 via the plus side heat sink 18P, and the field coil 19 and the regulator 20 are also connected to the output terminal 21. The output terminal 21 is connected to the positive terminal of the battery 23 via the fuse 22.
[0005]
The power generation coil 12A is connected to the connection point between the positive side diode 14P and the negative side diode 14M, the power generation coil 12B is connected to the connection point between the positive side diode 15P and the negative side diode 15M, and the positive side diode 16P. The power generation coil 12C is connected to the connection point with the negative side diode 16M, and the neutral point of the three-phase power generation coils 12A, 12B, and 12C is connected to the connection point between the positive side diode 17P and the negative side diode 17M. Yes.
[0006]
The regulator 20 is an IC regulator provided with capacitors 24, 25, and 26. A coupler 31 is provided at the end of the three lead wires 27, 28, and 29 connected to the regulator 20 . generating coil 12A, 12B, the leads 30 from the neutral point of 12C is al provided in coupler 31. Of the lead wires 27 to 30, the lead wire 27 is connected to the positive terminal of the battery 23 via the charge lamp 32 and the key switch 33, and the negative terminal of the battery 23 is connected to the negative diodes 14M, 15M, 16M, Each anode of 17M is connected to a negative heat sink 18M electrically connected in parallel.
[0007]
The conventional mechanical structure of the alternator 11 will be described next. As shown in FIGS. 12 and 13, the stator 13 is formed by winding a stator coil 12 around an iron core in which a plurality of annular core plates are laminated. The stator 13 is sandwiched between the rear bracket 35 and the front bracket 36. The rear bracket 35 and the front bracket 36 are fastened to each other by a plurality of through bolts 37, and the stator 13 is sandwiched between the rear bracket 35 and the front bracket 36.
[0008]
Cylindrical boss portions 38 and 39 are coaxially provided at the center of the rear bracket 35 and the front bracket 36, and a part of the rotary shaft 40 is rotatably supported by a bearing 41 on the boss portion 38 of the rear bracket 35. Has been. The other end of the rotating shaft 40 protrudes outward through the boss portion 39 of the front bracket 36, and a bearing 42 is interposed between the boss portion 39 and the rotating shaft 40.
[0009]
A so-called claw pole type rotor 43, called a Landel type rotor, is fixed to the rotating shaft 40 inside the stator 13 so as to be coaxial with the stator 13 and is inserted into the rotor 43. 44 is fixed to the inner surface side of the rear bracket 35 by a plurality of bolts 45. A field coil 19 is wound around the field iron core 44.
[0010]
A suction type cooling fan 46 is fixed to the rotary shaft 40 on the opposite side of the rotor 43 from the rear bracket 35, that is, on the outer side of the front bracket 36. A pulley 47 is fixed to the rotating shaft 40 further outward than the cooling fan 46, and a V-belt that transmits power from an engine (not shown) is wound around the pulley 47.
[0011]
The rear bracket 35 of the alternator 11 is attached with a resinous rear cover 51 so as to form a storage chamber 50 between the rear bracket 35 and the outside, and a plus-side heat sink provided with a plurality of rectifying diodes. 18P and the minus side heat sink 18M are attached to the outer surface side of the rear bracket 35 in the storage chamber 50 so as to be covered with the rear cover 51.
[0012]
The resinous rear cover 51 is attached to the rear bracket 35 by engaging a plurality of engaging claws 81 provided on the side surface portion of the rear cover 51 with the engaging portions provided on the rear bracket 35. The surface portion of 35 is attached and fixed to the boss portion 82 of the rear bracket 35 with a bolt 84 using a wide washer 83.
[0013]
The plus-side heat sink 18P and the minus-side heat sink 18M are arcuate shapes that support one end of the rotating shaft 40 and surround a part of the boss portion 38 provided on the rear bracket 35, so as to reduce the weight. It is made of an aluminum alloy. Further, on the surface of the plus side heat sink 18P facing the minus side heat sink 18M, the plus side diode 15P (actually four pieces including the plus side diodes 14P, 16P, and 17P) are soldered at one end thereof in the circumferential direction. And a negative diode 15M (actually four diodes including negative diodes 14M, 16M, and 17M) at one end of the negative heat sink 18M facing the positive heat sink 18P. It is attached with a gap in the circumferential direction so as to be soldered. That is, as described with reference to FIG. 11, the plus side diodes 14P to 17P are attached in a state of being electrically connected in parallel to the plus side heat sink 18P, and the minus side diodes 14M to 17M are electrically parallel to the minus side heat sink 18M. It is attached in a connected state. In addition, the positive side diodes 14P to 17P and the negative side diodes 14M to 17M, which are connected in parallel, are attached to both the heat sinks of the positive side heat sink 18P and the negative side heat sink 18M at positions corresponding to each other.
[0014]
The rear cover 51 is provided with a plurality of air introduction holes 89 and a cooling air introduction part provided with a plurality of air guide plates 90 extending inwardly connected to the edges of the air introduction holes 89. And a simple air inlet 91 for the hole 91.
[0015]
Reference numeral 85 denotes a connection coupler (corresponding to the coupler 31 in FIG. 11) that accommodates lead wires from the minus side heat sink 18M, the plus side heat sink 18P, and the like, and the coupler 85 is located above the rear bracket 35 via the coupler base 86. It is fixed to.
[0016]
[Problems to be solved by the invention]
In recent automobiles, various lights and motors are used in addition to heating in the winter and cooling in the summer. Therefore, the load on the alternator 11 is heavy, and the stator coil 12 and the field coil 19 are used. Tends to be hot. The rear bracket 35 is heated by conduction heat or radiant heat using these high temperatures as a heat source, and the minus heat sink 18M and the regulator 20 directly attached to the rear bracket 35 are difficult to avoid the influence of the conduction heat and radiant heat. It is.
[0017]
In addition, the cooling air from the hole 91 provided in the rear cover 51 flows as indicated by an arrow A in FIG. 14, and the cooling air flowing to the minus-side heat sink 18M is more positive than the cooling air flowing toward the plus-side heat sink 18P. Since it is blocked by the side heat sink 18P, it is unavoidable that an unbalance of the cooling temperature occurs during cooling.
[0018]
Further, the regulator 20 that is cooled by the cooling air from the air introduction hole 89 shown in FIG. 15 also has a structure that is directly attached to the rear bracket 35 via the heat sink 52, and therefore flows as indicated by an arrow B in FIG. Although it is cooled by the cooling air, there is a concern about the influence of the conduction heat from the rear bracket 35.
[0019]
In particular, the cooling by the cooling fan 46 has been focused on the high-speed rotation range, but the improvement of the cooling performance in the low / medium-speed range has become an issue due to the increase in the number of installed devices in the market.
[0020]
Further, further improvement in performance of the air guide plate 90 provided in the air introduction hole 89 provided in the conventional rear cover 51 has been desired.
[0021]
Then, a plurality of engaging claws 81 provided on the side surface portion of the rear cover 51 and a bolt 84 for fixing the planar surface portion of the rear cover 51 to the boss portion 82 of the rear bracket 35 together with the wide washer 83 are fixed. Further improvement of the fixing structure of the rear cover 51 is also desired.
[0022]
The present invention has been made in view of the above points, and a regulator-mounted heat sink coupling in which an insulating member having excellent heat insulation is sandwiched between a plus-side heat sink and a minus-side heat sink, and a regulator is attached to the minus-side heat sink. In the assembly, a gap is formed by a collar portion provided on a connector insulating substrate that blocks radiant heat and conduction heat from the rear bracket side, and a first air introduction portion and a second air introduction portion are provided on the rear cover. Thus, it is an object of the present invention to provide a vehicular AC generator in which a regulator-mounted heat sink coupling assembly to which a regulator is attached is cooled, and the regulator-mounted heat sink coupling assembly and other parts are efficiently cooled.
[0023]
[Means for Solving the Problems]
In order to solve the above-described object, an automotive alternator according to the present invention includes a rotor rotatably supported inward of a stator sandwiched between a rear bracket and a front bracket, and wound around the stator. The positive side heat sink and the negative side heat sink each having a plurality of positive side diodes and a plurality of negative side diodes for rectifying the generated voltage of the mounted stator coil (power generation coil) and the rectified output thereof are a constant voltage. In a vehicle AC generator having a structure in which the rear portion of the rear bracket is covered with a rear cover provided with a cooling air introduction portion, heat insulation is provided between the positive heat sink and the negative heat sink. The above regulator is attached to the negative heat sink. The heat sink coupling assembly and the connector terminal are provided, and the connector terminal is provided and is fixed to the rear bracket which has a convex collar portion and prevents radiant heat from the rear bracket side and conduction heat from the rear bracket. A connector insulating substrate, a first air introduction portion for introducing cooling air to the regulator and the minus side heat sink, and a rear cover provided with a second air introduction portion for introducing cooling air to the plus side heat sink and the rear bracket. The collar portion provides a gap between the regulator mounting heat sink coupling assembly and the connector insulating substrate, and each component is cooled by cooling air introduced from the first air introduction portion and the second air introduction portion, respectively. It features a structure that allows efficient cooling.
[0024]
The rear cover is formed of a resin cover, and an engaging claw and a hook portion are formed on a side surface portion of the resin cover, and the rear bracket corresponds to the engaging claw and the hook portion. The engagement portion is formed at each position, and the rear cover is fixed to the rear bracket by the engagement claw and the hook portion formed on the side surface portion of the rear cover. The coupler housing the wire is fixed to the rear bracket with a coupler holder that fixes the planar surface portion of the rear cover.
[0025]
The rear cover is provided with a first air introduction part for introducing cooling air into the regulator and the minus side heat sink, and a second air introduction part for introducing cooling air into the plus side heat sink and the rear bracket.
[0026]
An air guide plate is provided in a part of the cooling air introduction part for introducing the cooling air provided in the rear cover, so that the angle of the rear cover plane surface part with respect to the perpendicular is 30 ° to 40 °.
[0027]
Radiation heat from the rear bracket side and its conduction heat are blocked by the connector insulating substrate, and the regulator-mounted heat sink coupling assembly is cooled by cooling air from the first air introduction portion and the second air introduction portion provided in the rear cover. Etc. are cooled efficiently.
[0028]
DETAILED DESCRIPTION OF THE INVENTION
FIG. 1 shows a cross-sectional view of an embodiment of an automotive alternator according to the present invention. The same components as those in FIG.
[0029]
In FIG. 1, the difference from FIG. 12 is that the field iron core 44 has a structure attached to the front bracket 36 side, and that the inner fan fan 87 is newly provided on the side surface of the rotor 43, The following points that characterize the present invention, that is, the regulator mounting heat sink coupling assembly 61 is attached to the rear bracket 35 via the connector insulating substrate 63, the shape and mounting structure of the rear cover 64, and the coupler 85 The fixing method and its position.
[0030]
Of the differences noted above, the field core 44 is structured to be attached to the front bracket 36 side, because the excitation (field) is on the front side, so the space on the rear side is used well. However, it is not directly related to the present invention, and other small differences other than those mentioned above are not directly related to the present invention. Is omitted.
[0031]
The point that the regulator-mounted heat sink coupling assembly 61 is attached to the rear bracket 35 via the connector insulating substrate 63 will be described in more detail with reference to FIGS. 3 to 5. The voltage generated in the stator coil 12 is rectified. Between the plus-side heat sink 18P and the minus-side heat sink 18M to which the plurality of plus-side diodes D and the plurality of minus-side diodes D are respectively attached, an insulating sheet having excellent heat insulation and insulation properties (for example, A Nomex sheet (trade name) 65 is formed in a sandwiched state, and the regulator 20 is attached to the negative heat sink 18M as shown in FIG. The regulator mounting heat sink coupling assembly 61 has a collar portion 62 (see FIGS. 1 and 5) in consideration of the electrical insulation of the plus heat sink 18P with the rear bracket 35 as well as the overall ventilation and thermal insulation. It is integrally formed and fixed to the rear bracket 35 via a connector insulating substrate 63 made of resin or the like.
[0032]
By using a magnetic material for the minus-side heat sink 18M to which the regulator 20 is attached, a magnetic shielding effect can be expected in combination with the case of the regulator 20.
[0033]
The connector insulating substrate 63 is provided with external electronic components and is provided with connector terminals 66 and lead wire protection terminals 67 as will be described later with reference to FIGS. 66 and the lead wire protection terminal 67 are used for connection to the regulator 20, the field coil 19, and the like, and are used to protect the lead wires. Reference numeral 68 denotes a protective stud that protects the rear cover 64.
[0034]
Needless to say, the connector insulating substrate 63 plays a role of blocking radiation heat from the rear bracket 35 side such as heat generation of the stator coil 12 and conduction heat from the rear bracket 35. Further, as will be described later, both the plus-side heat sink 18P and the minus-side heat sink 18M pass through the gap with the connector insulating substrate 63 due to the thickness of the convex collar portion 62 provided on the connector insulating substrate 63. It becomes easy and the cooling is promoted.
[0035]
FIG. 2 is a left side view of FIG. 1, and the rear cover 64 has a shape provided with a cover protrusion 69 that covers the regulator-mounted heat sink coupling assembly 61 attached to the rear bracket 35. . The rear cover 64 is formed of a synthetic resin member, and a plurality of engaging claws 70 (see FIGS. 6 to 8) and one hook portion 71 (see FIG. 6) are formed on the side surface of the rear cover 64, for example. To the rear bracket 35, and engaging portions 72 and 73 (see FIGS. 6 to 8) for engaging with the engaging claws 70 and the hook portion 71 are formed. The rear cover 64 is fixed to the rear bracket 35 by these engaging claws 70 and hook portions 71 formed on the side surface portion of the rear cover 64.
[0036]
When the rear cover 64 is attached to the rear bracket 35, the front end surface of the protective stud 68 provided on the regulator mounting heat sink coupling assembly 61 abuts against the inner surface of the rear cover 64, maintaining the flatness of the rear cover 64 and from the outside. Indentation due to beating is prevented, and the external beauty is maintained.
[0037]
The coupler 85 containing the lead wires from the connector insulating substrate 63 and the like is screwed while pressing the planar surface portion of the rear cover 64 with a predetermined area via the coupler base 86, and the rear cover 64 is fixed to the rear bracket 35. Yes.
[0038]
A plurality of air introduction holes 74 are appropriately formed in the rear cover 64 shown in FIG. 2, and # 1 cooling air X1 and # 2 cooling air X2 introduced from these air introduction holes 74 are, for example, Flows as shown by the thick lines with arrows in FIGS.
[0039]
That is, the negative heat sink 18M and the regulator 20 are mainly cooled by the # 1 cooling air X1 shown in FIG. 6, and the positive heat sink 18P and the rear bracket 35 are cooled by the # 2 cooling air X2 shown in FIG. Mainly cooled.
[0040]
In short, the parts that require heat radiation are concentrated on the surface of the rear cover 64 and are effectively cooled by # 1 cooling air X1 and # 2 cooling air X2 introduced from the air introduction hole 74. The # 1 cooling air X1 flowing in the alternator 11 as shown in FIG. 6 and the # 2 cooling air X2 flowing as shown in FIG. 7 are newly provided on the side surface of the rotor 43 in cooperation with the cooling fan 46. In 87, the inflow of cooling air is promoted and enhanced, and this cooling effect becomes more remarkable.
[0041]
FIG. 8 shows another embodiment of the air introduction hole provided in the rear cover.
[0042]
In the figure, the rear cover 76 is provided with a plurality of air introduction holes 77 instead of the plurality of air introduction holes 74 shown in FIG. Each of the plurality of air introduction holes 77 provided in the rear cover 76 is integrally formed with an air guide plate 78, and the air guide plate 78 has an angle with respect to the normal of the planar surface portion of the rear cover 76 as shown in the figure. It is formed at ˜40 °.
[0043]
Thus, by forming the angle of the air guide plate 78 with respect to the normal of the planar surface portion of the rear cover 76 to 30 ° to 40 °, the cooling air introduced into the alternator 11, that is, the air introduction hole provided in the rear cover 76. The external air taken in from 77 efficiently cools the plus-side heat sink 18P or the minus-side heat sink 18M, the windings, and the like.
[0044]
9 and 10 show temperature rise characteristics based on experiments when the angle of the air guide plate is changed. FIG. 9 is for high-speed wind, and FIG. 10 is for low and medium-speed wind. In FIG. 9 and FIG. 10, P1 to P7 are obtained by measuring the parts having the same reference numerals.
[0045]
As can be seen from FIG. 9, when the wind is high speed, the angle of the air guide plate 78 is 45 ° or more and the temperature rise value is the lowest, so the angle of 45 ° has been conventionally used. On the other hand, when the wind is low / medium speed, the temperature rise value is the lowest when the angle of the air guide plate 82 is around 30 °.
[0046]
From this experimental result, when the rear cover 76 having the air introduction hole 77 having the structure as shown in FIG. 8 is used, the angle of the air guide plate 78 of the rear cover 76 should be 30 ° to 40 °. In addition, each temperature rise value in the alternator 11 in the low / medium speed range where the temperature rise is severe can be suppressed most, and the most effective cooling can be expected. At this time, the cooling air introduced along the air guide plate 78 of the rear cover 76 can be easily led to a cooling target portion such as the regulator-mounted heat sink coupling assembly 61, and the simple air introduction hole shown in FIG. Compared with 74, the cooling effect can be further expected.
[0047]
【The invention's effect】
As described above, according to the present invention, a regulator-mounted heat sink coupling assembly in which an insulating member having excellent heat insulation is sandwiched between a plus-side heat sink and a minus-side heat sink, and a regulator is attached to the rear cover-side heat sink. Incorporated from the rear cover as a structure that prevents the radiant heat from the bracket side and conduction heat from the rear bracket while making it easy for the cooling air to pass through the regulator mounting heat sink coupling assembly with the connector insulation board having the collar part The produced cooling air cools each component efficiently.
[0048]
The rear cover is formed of a synthetic resin cover, and the engaging claw and the hook portion are formed on the side surface portion of the resin cover, and the rear cover is formed by the engaging claw and the hook portion formed on the side surface portion of the rear cover. With a structure that is fixed to the rear bracket, and a coupler holder that fixes the coupler housing the lead wire from the connector insulating board to the rear bracket, the planar surface portion of the rear cover is pressed with a predetermined area and screwed. In addition to being inexpensive and easy to mount, the coupler holder having a predetermined area can prevent deformation and vibration of the rear cover.
[0049]
In addition, in the structure where the air introduction part of the rear cover is provided with an introduction plate whose angle with respect to the normal of the surface part of the rear cover plane is in the range of 30 ° to 40 °, the cooling efficiency is improved in the low / medium speed rotation region where the temperature rise is severe. This can contribute to reduction in size and weight.
[0050]
Further, since the regulator-mounted heat sink coupling assembly can be made smaller, ventilation is further improved and a synergistic effect is exhibited, and this synergistic effect further promotes cooling of the parts.
[Brief description of the drawings]
FIG. 1 is a cross-sectional view of an embodiment of an AC generator for a vehicle according to the present invention.
FIG. 2 is a left side view of FIG.
3 is a left side view of FIG. 1 with a rear cover removed. FIG.
FIG. 4 is a plan view of a heat sink coupling assembly.
FIG. 5 is a front view of FIG. 4;
FIG. 6 is a diagram for explaining a main flow of cooling air taken from an air introduction hole.
FIG. 7 is a diagram for explaining the main flow of cooling air taken from other air introduction holes.
FIG. 8 is an explanatory view of another embodiment of the air introduction hole provided in the rear cover.
FIG. 9 is a temperature rise characteristic diagram based on an experiment when the air guide plate angle is changed.
FIG. 10 is a temperature rise characteristic diagram based on an experiment when the air guide plate angle is changed.
FIG. 11 is a general electric circuit diagram of an automotive alternator mounted on an automobile.
FIG. 12 is a cross-sectional view of a conventional vehicle alternator.
13 is a left side view of FIG.
FIG. 14 is a diagram for explaining the main flow of cooling air taken from the lower part of a conventional rear cover.
FIG. 15 is an explanatory diagram showing the main flow of cooling air taken from the upper part of a conventional rear cover.
[Explanation of symbols]
11 Alternator 12 Stator coils 12A, 12B, 12C Generator coil 13 Stator 14P, 15P, 16P, 17P Positive side diodes 14M, 15M, 16M, 17M Negative side diode 18P Plus side heat sink 18M Negative side heat sink 19 Field coil 20 Regulator 31 Coupler 35 Rear Bracket 36 Front Bracket 43 Rotor 44 Field Core 46 Cooling Fan 50 Storage Chamber 51 Rear Cover 52 Heat Sink 61 Regulator Mounted Heat Sink Assembly 62 Collar 63 Connector Insulating Substrate 64 Rear Cover 65 Insulating Sheet 70 Engaging Claw 71 Hook 72 73 Engagement portion 74 Air introduction hole 76 Rear cover 77 Air introduction hole 78 Air guide plate 81 Engagement claw 85 Coupler 86 Coupler base 87 Inner fan 89 Air introduction 90 baffle plate 91 holes

Claims (3)

A rotor rotatably supported inward of the stator sandwiched between the rear bracket and the front bracket, and a plurality of rectifiers for rectifying the generated voltage of the stator coil (power generation coil) wound around the stator A positive side heat sink and a negative side heat sink each having a positive side diode and a plurality of negative side diodes attached thereto and a regulator for controlling the rectified output to a constant voltage are provided, and an air introduction unit for cooling is provided. In the vehicle AC generator having a structure in which the rear portion of the rear bracket is covered with the rear cover,
A regulator-mounted heat sink coupling assembly in which an insulating member with excellent heat insulation is sandwiched between the plus side heat sink and the minus side heat sink, and the regulator is attached to the minus side heat sink,
A connector terminal provided with a connector terminal, and having a convex collar portion and fixed to the rear bracket for preventing radiant heat from the rear bracket side and conduction heat from the rear bracket;
A first air introduction part for introducing cooling air into the regulator and the minus side heat sink, and a rear cover provided with a second air introduction part for introducing cooling air into the plus side heat sink and the rear bracket, The collar portion provides a gap between the regulator-mounted heat sink coupling assembly and the connector insulating board, and the cooling air introduced from the first air introduction portion and the second air introduction portion respectively allows each component to be efficiently performed. A vehicle alternator characterized by a cooled structure.   The rear cover is formed of a resinous cover, and an engaging claw and a hook part are formed on a side surface portion of the resinous cover, and the rear bracket has a position corresponding to the engaging claw and the hook part. Each of the engaging portions is formed on the side surface of the rear cover, and the rear cover is fixed to the rear bracket by the engaging claws and hook portions formed on the side surface of the rear cover. 2. The vehicular AC generator according to claim 1, further comprising a coupler holder that fixes the coupler in which the housing is housed to the rear bracket so that the flat surface portion of the rear cover is pressed. Claim at least said air inlet portion, the in part provided baffle plates, conductor cooling air ducts, characterized in that the angle relative to the normal of the rear cover flat surface portion is formed at 30 ° to 40 ° The AC generator for vehicles according to 1 or 2 .

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