JP2010288400A - Ac generator for vehicle and method of manufacturing rectifier mounted thereon - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an AC generator for vehicle, wherein the radiation area can be enlarged by utilizing the installation space in the case efficiently, and the AC generator can be assembled easily without increasing the number of parts, and to provide a method of manufacturing a rectifier mounted thereon. <P>SOLUTION: The rectifier 20 is constituted of: first and second heat sinks 27 and 33 which are arranged substantially concentrically and side by side in the radial direction while having first and second heat sink bases 28 and 34 made into cylindrical bodies with arcuate cross-sections, and radiation fins 29 and 35 erected on the outer circumferential wall surfaces of the first and second heat sink bases 28 and 34 respectively; and diodes 21 and 22 on the positive electrode side and the negative electrode side which are mounted on the inner circumferential wall surface of the first and second heat sink bases 28 and 34 with a space therebetween in the circumferential direction, wherein the first and second heat sink bases 28 and 34 are made by arcuately bending a planar base member mounting the diodes 21 and 22 on the positive and negative electrode sides. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to an automotive alternator and a method of manufacturing a rectifier mounted thereon, and more particularly to a heat sink structure of the rectifier.

  A conventional first rectifying device mounted on a vehicle alternator is configured as an integrated body formed by connecting two arms in a V shape, and a radiator having a fixed lug at each end of the V shape, It is fixed to the rear bearing by screws or tie rods passed through the respective fixing lugs, and is disposed in the case of the vehicle alternator. Each arm between the fixed lugs includes a base, a plurality of radiating fins protruding inward in the radial direction from the base, extending in the axial direction, and juxtaposed in the length direction of the base, and the base A wall projecting radially outward from a flat back surface parallel to the axial direction of the radially outer side and extending in a direction orthogonal to the axial direction, and the diode is brazed to a surface orthogonal to the axial direction of the wall (For example, refer to FIG. 9 of Patent Document 1).

  Further, in the conventional second rectifier mounted on the vehicle alternator, two radiators each having fixed lugs at both ends are passed through the pair of stacked fixed lugs and the remaining two fixed lugs. It is fixed to the rear bearing by screws or tie rods and is arranged in a V shape in the case of the vehicle alternator. Each radiator has a base and a plurality of heat radiation fins that protrude radially inward from the base and extend in the axial direction, and are arranged in parallel in the length direction of the base. It is brazed on a flat surface parallel to the axial direction on the radially outer side of the base (see, for example, FIGS. 3 and 4 of Patent Document 1).

Japanese Patent No. 4187647

  In the first conventional rectifier, since the radiator is disposed in the case of the vehicle alternator so that the shaft is positioned in the V-shape, the outer diameter of the radiator is the same as the inner diameter of the case. Be constrained. Since the wall for mounting the diode protrudes radially outward from a flat surface parallel to the axial direction on the radially outer side of the base, the radial position of the base shifts to the inner diameter side by the amount of protrusion of the wall. become. Therefore, there has been a problem that the radial height of the heat radiating fin is reduced, the heat radiating area is reduced, and the cooling capacity of the radiator is lowered.

  On the other hand, in the conventional second rectifier, the diode is mounted on a flat surface parallel to the axially outer side of the base in the radial direction. It can be shifted to the radial side. Therefore, the radial height of the heat dissipating fins is increased, the heat dissipating area is increased, and the cooling capacity of the radiator can be increased. However, since the conventional second rectifier is divided into two radiators, there is a problem that the number of parts increases and the assemblability deteriorates.

  The present invention has been made in order to solve such problems, and can be easily assembled without increasing the heat radiation area by efficiently using the installation space in the case and increasing the number of parts. It is an object of the present invention to obtain a vehicle AC generator and a method for manufacturing a rectifier mounted thereon.

  An automotive alternator according to the present invention includes a case, a rotor fixed to a shaft supported by the case and disposed in the case, and an outer periphery of the rotor supported by the case. The stator coil is wound around the stator core, and is arranged on one side of the rotor in the axial direction of the rotor and electrically connected to the stator coil And a rectifier that rectifies alternating current generated in the stator coil into direct current, and a fan that is fixed to an end face on one side in the axial direction of the rotor. The rectifier includes a heat sink base formed in a cylindrical body having an arc-shaped cross section, and a plurality of heat radiating fins standing on at least one of the inner peripheral wall surface and the outer peripheral wall surface of the heat sink base and extending in the axial direction. Two heat sinks arranged substantially concentrically around the axis of the shaft and arranged in the radial direction, and spaced apart from each other in the circumferential direction on one of the inner wall surface and the outer wall surface of the heat sink base The heat sink base is produced by bending a flat base member on which the plurality of rectifying components are mounted in an arc shape.

According to this invention, the heat sink base is produced by bending a flat base member into an arc shape. Therefore, it is possible to easily produce a cylindrical heat sink base having an arc-shaped cross section that can increase the heat radiation area, without using a low yield method such as extrusion or cutting. Further, the heat sink can be manufactured as a single component, and an increase in the number of components can be suppressed.
Also, since the flat base member on which the rectifying component is mounted is bent, the mounting direction of the rectifying component on the base member is only in the direction perpendicular to the surface of the base member, and the assembly of the rectifying device is facilitated. .

1 is a longitudinal sectional view showing an automotive alternator according to Embodiment 1 of the present invention. It is a side view which shows the rectifier mounted in the vehicle alternator which concerns on Embodiment 1 of this invention. It is a figure explaining the structure of the diode used for the rectifier mounted in the alternating current generator for vehicles which concerns on Embodiment 1 of this invention. It is process drawing explaining the manufacturing method of the rectifier mounted in the alternating current generator for vehicles which concerns on Embodiment 1 of this invention. It is process drawing explaining the manufacturing method of the rectifier mounted in the alternating current generator for vehicles which concerns on Embodiment 1 of this invention. It is an electric circuit diagram in the vehicle alternator according to Embodiment 1 of the present invention. It is a principal part side view explaining the manufacturing method of the rectifier mounted in the alternating current generator for vehicles which concerns on Embodiment 2 of this invention. It is a side view which shows the 2nd heat sink assembly of the rectifier mounted in the alternating current generator for vehicles concerning Embodiment 3 of this invention. It is a side view which shows the 2nd heat sink assembly of the rectifier mounted in the alternating current generator for vehicles concerning Embodiment 4 of this invention. It is a principal part side view which shows the 2nd heat sink assembly of the rectifier mounted in the alternating current generator for vehicles concerning Embodiment 5 of this invention. It is a principal part side view explaining the manufacturing method of the 2nd heat sink assembly of the rectifier mounted in the alternating current generator for vehicles concerning Embodiment 6 of this invention. It is a side view which shows the 2nd heat sink assembly of the rectifier mounted in the alternating current generator for vehicles concerning Embodiment 7 of this invention. It is a figure explaining the structure of the 2nd heat sink assembly of the rectifier mounted in the alternating current generator for vehicles concerning Embodiment 8 of this invention. It is principal part sectional drawing which shows the surroundings of the rectifier of the alternating current generator for vehicles which concerns on Embodiment 9 of this invention. It is principal part sectional drawing which shows the surroundings of the rectifier of the alternating current generator for vehicles which concerns on Embodiment 10 of this invention. It is a side view explaining the manufacturing method of the 2nd heat sink assembly of the rectifier mounted in the alternating current generator for vehicles concerning Embodiment 11 of this invention.

Embodiment 1 FIG.
1 is a longitudinal sectional view showing an automotive alternator according to Embodiment 1 of the present invention, and FIG. 2 is a side view showing a rectifier mounted on the automotive alternator according to Embodiment 1 of the present invention. FIG. 3 is a diagram for explaining the configuration of a diode used in the rectifier mounted on the automotive alternator according to Embodiment 1 of the present invention, in which FIG. 3 (a) is a side view thereof, and FIG. (B) is a top view thereof. FIG. 4 is a process diagram for explaining a method of manufacturing a rectifier mounted on an automotive alternator according to Embodiment 1 of the present invention, and FIG. 5 shows an automotive alternator according to Embodiment 1 of the present invention. FIG. 6 is a process diagram for explaining a method of manufacturing the mounted rectifier, and FIG. 6 is an electric circuit diagram in the vehicle AC generator according to Embodiment 1 of the present invention.

  In FIG. 1, an AC generator 100 for a vehicle includes a case 1 made of a substantially bowl-shaped aluminum front bracket 2 and a rear bracket 3, and a shaft 18 supported by the case 1 via a bearing 4. 1 is fixed to both end surfaces of the rotor 15 in the axial direction, the rotor 15 disposed rotatably in the rotor 1, the pulley 5 fixed to the end of the shaft 18 extending to the front side of the case 1. The fan 6 has a fixed air gap with respect to the rotor 15, surrounds the outer periphery of the rotor 15, is fixed to the case 1, and is fixed to the rear side of the shaft 18. A pair of slip rings 7 that supply current to 15, a pair of brushes 8 that slide on the surface of each slip ring 7, a brush holder 9 that houses these brushes 8, and a stator 12. Fixed A voltage regulator 11 that is attached to a heat sink 10 fitted to the brush holder 9 and adjusts the magnitude of the AC voltage generated in the stator 12; It has.

The stator 12 is wound around the cylindrical stator core 13, the stator core 13, and a stator coil 14 in which an alternating current is generated by a change in magnetic flux from the field coil 16 as the rotor 15 rotates. It has.
The rotor 15 includes a field coil 16 that generates a magnetic flux when an excitation current is passed, a pole core 17 that is provided so as to cover the field coil 16, and a magnetic pole is formed by the magnetic flux, and an axial center position of the pole core 17. And a shaft 18 penetrating therethrough. The fan 6 is fixed to both end surfaces of the pole core 17 in the axial direction by welding or the like.

Next, the configuration of the rectifier 20 will be described.
As shown in FIGS. 1 and 2, the rectifying device 20 includes a positive-side diode 21 as a rectifying component, a negative-side diode 22 as a rectifying component, a first heat sink 27 that supports the positive-side diode 21, and a negative electrode A second heat sink 33 that supports the side diode 22, and a circuit board 40 that electrically connects the positive and negative side diodes 21 and 22 and the stator coil 14 are provided.

  As shown in FIG. 3, the positive-side diode 21 includes a rectifying element 23 formed by pn junction of an N-type semiconductor and a P-type semiconductor, and a surface of the rectifying element 23 opposite to the P-type semiconductor of the N-type semiconductor. A copper base 24 soldered to the substrate, an insulating resin portion 25 formed by molding the rectifying element 23 and the copper base 24 into a substantially rectangular parallelepiped shape, and one end connected to the P-type semiconductor of the rectifying element 23 to form an insulating resin. A lead terminal 26a extending from the section 25 and having the other end connected to the circuit board is provided. Similarly, the negative electrode side diode 22 is formed by molding a rectifying element 23, a copper base 24 solder-bonded to a surface opposite to the N-type semiconductor of the P-type semiconductor of the rectifying element 23, and the rectifying element 23 and the copper base 24. An insulating resin portion 25 formed in a substantially rectangular parallelepiped, and a lead terminal 26b having one end connected to the N-type semiconductor of the rectifying element 23 and extending from the insulating resin portion 25 and the other end connected to the circuit board 40 I have.

  The first heat sink 27 is made of a heat conductive material such as aluminum or copper, has a predetermined axial length (width) and a predetermined radial width (thickness), and has a circular cross section perpendicular to the axial direction. A first heat sink base 28 bent into an arcuate cylinder, and a plurality of radiating fins extending radially from the outer peripheral wall surface of the first heat sink base 28 at a predetermined pitch in the circumferential direction and extending in the axial direction. 29, and a fixed lug 30 that is bent in an L shape from one end in the circumferential direction of the first heat sink base 28 and one axial end of the central portion and extends radially outward. The fixing lug 30 is formed with a hole 31 for inserting a fixing member such as a mounting bolt.

  Further, three positive-side diode mounting regions (hereinafter referred to as diode mounting surfaces) in which positioning protrusions 32 are provided on the inner peripheral wall surfaces of the first heat sink bases 28 between the fixed lugs 30 at predetermined intervals in the circumferential direction. Projecting at a predetermined height on both sides in the circumferential direction and extending in the axial direction. The positive-side diode 21 is positioned by the positioning protrusion 32 and placed on each diode mounting surface, and the copper base 24 is soldered and mounted.

  The second heat sink 33 is made of a good heat conductive material such as aluminum or copper, has a predetermined axial length (width) and a predetermined radial width (thickness), and a cross section perpendicular to the axial direction is a circle. A second heat sink base 34 bent into an arcuate cylindrical body, and a plurality of radiating fins extending radially from the outer peripheral wall surface of the second heat sink base 34 at a predetermined pitch in the circumferential direction and extending in the axial direction. 35 and fixed lugs 36 formed at both ends and the center of the second heat sink base 34 in the circumferential direction. The fixing lug 36 has a hole 37 through which a fixing member such as a mounting bolt is inserted. The inner diameter of the second heat sink base 34 is made larger than the outer diameter of the arc formed by the extended ends of the radiating fins 29 radiating from the outer peripheral wall surface of the first heat sink base 28.

  Further, three negative-side diode mounting regions (hereinafter referred to as diode mounting surfaces) in which positioning protrusions 38 are provided on the inner peripheral wall surface of each second heat sink base 34 between the fixed lugs 36 at predetermined intervals in the circumferential direction. Projecting at a predetermined height on both sides in the circumferential direction and extending in the axial direction. The negative-side diode 22 is positioned by the positioning protrusion 38 and placed on each diode mounting surface, and the copper base 24 is soldered and mounted.

  As shown in FIG. 2, the first and second heat sinks 27 and 33 manufactured in this way are arranged concentrically with the fixing lugs 36 and 30 overlapped with an insulating cylinder 39 interposed therebetween. Although not shown, the circuit board 40 is overlapped, and the mounting bolt is passed through the circuit board 40 and the holes 31 and 37 and fastened to the inner wall surface of the rear bracket 3 to be attached to the case 1. At this time, the first and second heat sinks 27 and 33 are disposed substantially concentrically with respect to the axis of the shaft 18. The second heat sink 33 secures a thermal contact state with the inner wall surface of the rear bracket 3 and is electrically connected and grounded. The first heat sink 27 is attached to the second heat sink 33 and the rear bracket 3 in an electrically insulated state. The brush holder 9 is disposed between both ends of the arc-shaped first and second heat sinks 27 and 33 in the circumferential direction.

  Here, the circuit board 40 is a resin molded body in which a plurality of insert conductors are insert-molded, and an end portion of the insert conductor is exposed to form a connection terminal. The lead terminals 26 a and 26 b of the positive and negative diodes 21 and 22 are connected to the circuit board 40, and the lead wires 41 of the windings 14 a to 14 f constituting the stator coil 14 are connected to the circuit board 40. Connected to the terminal.

  Thus, as shown in FIG. 6, the rectifying device 20 includes two diode rectifiers 20A and 20B each including a diode bridge formed by three diode pairs in which a positive diode 21 and a negative diode 22 are connected in series. Composed.

  As shown in FIG. 6, the stator coil 14 includes a three-phase AC winding 14A formed by Y-connecting three windings 14a, 14b, and 14c, and three windings 14d, 14e, and 14f. The three-phase AC winding 14B is formed by connection, and the output ends of the windings 14a, 14b, 14c, 14d, 14e, and 14f are connected to the positive-side diode 21 and the negative-side diode 22 of each diode pair. Connected to the connection point. The three-phase AC voltage output from each output end of the three-phase AC winding 14A is full-wave rectified and output by the rectifier 20A and output from each output end of the three-phase AC winding 14B. The voltage is full-wave rectified and output by the rectifier 20B.

Next, the operation of the vehicle alternator 100 configured as described above will be described.
First, a current is supplied from a battery (not shown) to the field coil 16 of the rotor 15 via the brush 8 and the slip ring 7 to generate a magnetic flux. With this magnetic flux, the pole core 17 is magnetized alternately into the N pole and the S pole in the circumferential direction.
On the other hand, the rotational torque of the engine is transmitted to the shaft 18 via a belt (not shown) and the pulley 5, and the rotor 15 is rotated. Therefore, a rotating magnetic field is applied to the stator coil 14 of the stator 12, and an electromotive force is generated in the stator coil 14. This AC electromotive force is rectified into a DC current by the rectifier 20, and the battery is charged or supplied to an electric load.

  At this time, the fan 6 is rotationally driven by the rotation of the rotor 15, and the cooling air is sucked into the rear bracket 3 from the intake hole 3 a formed in the end surface of the rear bracket 3. Then, the cooling air sucked into the rear bracket 3 flows axially between the radiation fins 29 and 35 and reaches the rotor 15. Further, the cooling air sucked into the rear bracket 3 flows radially inward along the heat sink 10 and then flows in the axial direction to reach the rotor 15. The cooling air that has flowed to the rotor 15 is bent in the centrifugal direction by the fan 6, and exhausted out of the rear bracket 3 through the exhaust hole 3 b formed in the side surface of the rear bracket 3. On the front side as well, cooling air is sucked from the intake holes 2 a formed in the end face of the front bracket 2, bent in the centrifugal direction by the fan 6, and from the exhaust holes 2 b formed in the side surfaces of the front bracket 2. The air is exhausted outside the front bracket 2.

  Therefore, the heat generated by the voltage regulator 11 is radiated to the cooling air flowing along the heat sink 10. Heat generated by the positive and negative diodes 21 and 22 of the rectifier 20 is radiated to the cooling air flowing between the heat radiation fins 29 and 35 of the first and second heat sinks 27 and 33. The heat generated in the stator coil 14 is dissipated from the front and rear coil ends to the cooling air bent in the centrifugal direction by the fan 6. Thereby, the heat generating components built in the case 1 such as the voltage regulator 11, the stator coil 14, and the rectifier 20 are cooled, an excessive temperature rise is suppressed, and the deterioration of the power generation performance is suppressed. The service life of parts can be extended.

  According to the first embodiment, the first heat sink base 28 bent into a cylindrical body having an arc cross section, and the plurality of heat radiation fins 29 radiating from the outer peripheral wall surface of the first heat sink base 28 are provided. A first heat sink 27, a second heat sink base 34 bent into a cylindrical body having a circular arc cross section, and a plurality of heat radiation fins 35 radiating from the outer peripheral wall surface of the second heat sink base 34. 2 heat sinks 33 are arranged concentrically, the positive diode 21 is mounted on the inner peripheral wall surface of the first heat sink base 28, and the negative diode 22 is mounted on the inner peripheral wall surface of the second heat sink base 34. .

Therefore, there is no increase in the radial width of the first and second heat sink bases 28 and 34, and the radial height of the heat radiation fins 29 and 35 can be increased. As a result, the heat radiation area increases, the cooling capacity of the first and second heat sinks 27 and 33 can be increased, and an excessive temperature rise of the positive and negative diodes 21 and 22 can be suppressed.
Further, since each of the first and second heat sinks 27 and 33 is composed of a single member, the number of parts is reduced, and the rectifier 20 can be easily assembled.

  A pair of positioning protrusions 32 and 38 protrude at a predetermined protrusion height on both sides in the circumferential direction of the respective diode mounting surfaces of the inner peripheral wall surfaces of the first and second heat sink bases 28 and 34 and extend in the axial direction. Yes. Accordingly, the positive and negative diodes 21 and 22 are placed on the respective diode mounting surfaces of the inner peripheral wall surfaces of the first and second heat sink bases 28 and 34 with the pair of positioning protrusions 32 and 38 as a guide, thereby positive electrodes. Since the positioning of the side and negative side diodes 21 and 22 is performed, the assembly of the rectifier 20 is improved.

Next, a method for manufacturing the rectifier 20 will be described with reference to FIGS. 4 and 5.
First, a second heat sink base material 55 shown in FIG. The second heat sink base material 55 is formed into a rectangular plate having a predetermined width and a predetermined thickness, and the fixed lugs 36 are formed at both ends and the center in the length direction, 2 A plurality of radiating fins 57 are provided so as to be perpendicular to the flat back surface of the base member 56 and extend in the width direction and arranged at a predetermined pitch in the length direction. Further, a pair of positioning projections 38 having a predetermined interval in the length direction and projecting at a predetermined height and extending in the width direction are provided between the fixed lugs 36 on the flat surface of the second base member 56. Three pairs of each are arranged at a predetermined pitch in the length direction.

Next, as shown in FIG. 4B, the negative-side diode 22 is placed on each of the pair of positioning protrusions 38 (diode mounting surface) from above the flat surface of the second base member 56. Then, the copper base 24 is soldered to the surface of the second base member 56, and the negative diode 22 is mounted.
Next, the second base member 56 is bent in an arc shape so that the surface of the second base member 56 is on the inner diameter side, and the negative diode 22 is mounted on the second heat sink 33 as shown in FIG. A second heat sink assembly is obtained.

  Next, a first heat sink base material 50 shown in FIG. 5A is prepared. The first heat sink base material 50 is formed in a rectangular plate having a predetermined width and a predetermined thickness, and the first base member 51 in which the fixing lugs 30 are formed at both ends and the center in the length direction, and A plurality of radiating fins 52 are provided so as to extend perpendicularly to the flat back surface of one base member 51 and extend in the width direction and arranged at a predetermined pitch in the length direction. Further, a pair of positioning projections 32 having a predetermined interval in the length direction and projecting at a predetermined height and extending in the width direction are provided between the fixed lugs 30 on the flat surface of the first base member 51. Three pairs of each are arranged at a predetermined pitch in the length direction. Further, the fixed lug 30 extends from one end of the length direction of the first base member 51 and the central portion to one side in the width direction in parallel with the surface of the first base member 51.

Next, as shown in FIG. 5B, the positive diode 21 is placed on each of the pair of positioning protrusions 32 (diode mounting surface) from above the flat surface of the first base member 51. Then, the copper base 24 is soldered to the surface of the first base member 51, and the positive diode 21 is mounted.
Next, as shown in FIG. 5C, each of the fixed lugs 30 is bent in an L shape on the back surface side of the first base member 51.
Next, the first base member 51 is bent into an arc shape so that the surface of the first base member 51 is on the inner diameter side, and the positive diode 21 is mounted on the first heat sink 27 as shown in FIG. A first heat sink assembly is obtained.

  Next, as shown in FIG. 2, the fixed lug 30 is placed on the fixed lug 36 with the insulating cylinder 39 interposed therebetween, and the first heat sink 27 and the second heat sink 33 are arranged concentrically. Further, the circuit board 40 is overlaid on the first and second heat sinks 27 and 33, and mounting bolts are passed through the circuit board 40 and the holes 31 and 37 of the fixing lugs 30 and 36, and fastened to the inner wall surface of the rear bracket 3. Thus, the rectifier 20 is assembled to the case 1.

Here, conventionally, the first and second heat sink bases having a circular arc section in cross section, and the first and second heat sinks provided with a plurality of radiation fins standing radially from the outer peripheral wall surface of the first and second heat sink bases. The two heat sinks were produced by a processing method such as extrusion or cutting, and the yield was poor.
However, according to the manufacturing method of the first embodiment, the first and second heat sink base materials 50 and 55 having the first and second base members 51 and 56 having a rectangular cross section are formed, and then the first Since the first and second heat sinks 27 and 33 are produced by bending the second heat sink base materials 50 and 55 into an arc shape, the yield can be dramatically improved.

  Further, according to the manufacturing method of the first embodiment, since the first and second heat sink base materials 50 and 55 are bent in an arc shape with the radiating fins 52 and 57 facing the outer diameter side, the radiating fins 52 and 57 57 can be spaced apart and formed radially, and the cooling performance of the first and second heat sinks 27 and 33 can be improved.

Conventionally, when a diode is mounted on the first and second heat sinks manufactured by a processing method such as extrusion or cutting, each diode on the inner peripheral wall surface of the first and second heat sink bases of the arcuate cylindrical body The diode is mounted on the mounting surface from the radial direction while moving in the circumferential direction, and the diode mounting process is extremely complicated.
However, according to the manufacturing method of the first embodiment, prior to bending the first and second heat sink base materials 50 and 55 into an arc shape, the positive and negative diodes 21 and 22 are connected to the first and second bases. It is mounted on the members 51 and 56. Therefore, the mounting direction of the positive side and negative side diodes 21 and 22 is only in the direction orthogonal to the flat surfaces of the first and second base members 51 and 56, and the mounting process of the positive side and negative side diodes 21 and 22 is remarkable. Simplified.

  In the first embodiment, when the first heat sink base material 50 is manufactured, the fixing lug 30 extending from the first base member 51 to one side in the width direction in parallel with the surface of the first base member 51 is simultaneously formed. However, the fixing lug 30 may be formed at the same time as being bent in an L shape from the first base member 51 to one side in the width direction when the first heat sink base material 50 is manufactured. In this case, the process of bending the fixed lug 30 into an L shape is unnecessary, and the manufacturing process of the first heat sink 27 is simplified.

Embodiment 2. FIG.
FIG. 7 is a main part side view for explaining a method of manufacturing a rectifier mounted on an automotive alternator according to Embodiment 2 of the present invention, and FIG. FIG. 7B shows a fixed state of the negative-side diode.

  In the second heat sink base material 55A according to the second embodiment, as shown in FIG. 7A, the fixing rod 42 is provided on the surface of the second base member 56 on both sides in the length direction of the diode mounting surface. Projecting to a predetermined height and extending in the width direction. The second heat sink base material 55A is manufactured in the same manner as the second heat sink base material 55 except that a fixing bar 42 is provided instead of the positioning protrusion 38.

  Then, when the second heat sink base material 55A mounted on the second base member 56 is bent into an arc shape, the negative diode 22 is bent in the length direction as shown in FIG. 7B. The negative-side diode 22 falls to the copper base 24 side of the negative-side diode 22 from both sides, and the negative-side diode 22 is caulked and fixed to a second heat sink base 34 that is bent into an arc shape. As a result, a second heat sink assembly in which the negative-side diode 22 is mounted on the second heat sink 33A is obtained.

  According to the second embodiment, in the bending process of the second heat sink base material 55A, the negative diode 22 is caulked and fixed by the fixing rod 42, so that the soldering process is not required, and the second heat sink is manufactured accordingly. The process is simplified.

  Here, also in the first heat sink base material, the fixing rod is similarly formed on the first base member, and the positive-side diode is caulked and fixed by the fixing rod by performing the bending process of the first heat sink base material. And mounted on the first heat sink.

  In the second embodiment, after the negative diode 22 is placed on the diode mounting surface of the second base member 56, the second heat sink base material 55A is bent into an arc shape so that the negative diode 22 becomes the second heat sink. The negative side diode 22 is placed on the diode mounting surface of the second base member 56 and the fixing rod 42 is bent to the negative side diode 22 side to be caulked and fixed. The heat sink base material 55A may be bent in an arc shape. In this case, since the second heat sink base material 55A can be bent with the negative electrode side diode 22 fixed, the negative electrode side diode 22 does not drop during the bending process, and the second heat sink base material 55A can be easily and stably supplied. The heat sink base material 55A can be bent.

  In the second embodiment, the negative diode 22 is placed on the diode mounting surface of the second base member 56, and then the second heat sink base material 55A is bent into an arc shape so that the negative diode 22 is connected to the second heat sink. Although the caulking is fixed to the base 34, the negative diode 22 is placed on the diode mounting surface of the second base member 56, the copper base 24 is soldered, and then the second heat sink base material 55A is bent into an arc shape. You may do it. In this case, since the second heat sink base material 55A can be bent while the negative electrode side diode 22 is fixed, the negative electrode side diode 22 does not drop in the bending process, and the second heat sink can be easily and stably. The base material 55A can be bent. Furthermore, since the negative electrode side diode 22 is fixed to the second heat sink base 34 by soldering and caulking, the negative electrode side diode 22 is held on the second heat sink base 34 with high strength.

Embodiment 3 FIG.
FIG. 8 is a side view showing a second heat sink assembly of the rectifier mounted on the vehicle alternator according to Embodiment 3 of the present invention.

In FIG. 8, the fixing lugs 36 are formed at four locations, ie, both ends in the circumferential direction of the second heat sink base 34 bent into a cylindrical body having a circular arc cross section and a portion that is divided into three in the circumferential direction. The heat radiating fins 35 are erected radially from the outer peripheral wall surface of the second heat sink base 34. In addition, two negative-side diodes 22 are arranged on the inner peripheral wall surface of each second heat sink base 34 between the fixed lugs 36, and the copper base 24 is soldered and mounted to produce the second heat sink 33B. Yes. Here, since the first heat sink is also manufactured in the same manner, the description thereof is omitted.
Other configurations are the same as those in the first embodiment.

  According to the third embodiment, since the distance between the fixed lugs 36 is shortened, the work of bending the heat sink base material into an arc shape is facilitated, the bending force is reduced, and the reliability of the second heat sink 33B is improved. Is done.

Embodiment 4 FIG.
FIG. 9 is a side view showing a second heat sink assembly of the rectifier mounted on the automotive alternator according to Embodiment 4 of the present invention.

In FIG. 9, the fixing lugs 36 are formed at three locations, ie, both ends in the circumferential direction and the central portion of the second heat sink base 34 which is bent and formed into a cylindrical body having an arcuate cross section. The heat radiating fins 35 are erected radially from the portion between the diode mounting surfaces of the inner peripheral wall surface of the second heat sink base 34. Further, the negative-side diode 22 is disposed on each diode mounting surface on the inner peripheral wall surface of each second heat sink base 34 between the fixed lugs 36, and the copper base 24 is soldered and mounted to produce the second heat sink 33C. Has been. Here, since the first heat sink is also manufactured in the same manner, the description thereof is omitted.
Other configurations are the same as those in the first embodiment.

  Since the first heat sink and the second heat sink 33C manufactured in this way are concentrically disposed in the rear bracket of the vehicle alternator, the heat radiating fins are disposed in the space on the inner diameter side where the flow velocity is relatively fast, The cooling performance of the first and second heat sinks is improved.

Embodiment 5 FIG.
FIG. 10 is a side view of the main part showing the second heat sink assembly of the rectifier mounted on the automotive alternator according to Embodiment 5 of the present invention.

In FIG. 10, in addition to the heat radiating fins 35, the second heat sink 33D is provided at a portion between the diode mounting surfaces on the inner peripheral wall surface of the second heat sink base 34 formed by bending the auxiliary heat radiating fins 43 into a cylindrical body having a circular arc cross section. It is erected. Here, since the first heat sink is also manufactured in the same manner, the description thereof is omitted.
Other configurations are the same as those in the first embodiment.

  According to the fifth embodiment, the radiating fins 35 are erected on the outer peripheral wall surface of the second heat sink base 34, and the auxiliary radiating fins 43 are erected on the inner peripheral wall surface of the second heat sink base 34. The heat dissipation area of the heat sink 33D is increased, and the cooling performance of the second heat sink 33D is improved.

Embodiment 6 FIG.
FIG. 11: is a principal part side view explaining the manufacturing method of the 2nd heat sink assembly of the rectifier mounted in the alternating current generator for vehicles concerning Embodiment 6 of this invention, (a) of FIG. 11 is 2nd. The state before the bending process of the heat sink assembly is shown, and FIG. 11B shows the state after the bending process of the second heat sink assembly.

  In the second heat sink base material 55B in the sixth embodiment, as shown in FIG. 11A, the first concave groove 44 as the bendable portion has the groove direction as the width direction and the surface of the second base member 56. Are extended in the width direction at the center between the diode mounting surfaces. Further, the second concave groove 45 as the bendable part has a groove direction in the width direction, and is located on the back surface of the second base member 56 so as to avoid the region facing the diode mounting surface and opposed to the first concave groove 44. It is extended in the width direction so as to sandwich.

  Then, the negative-side diode 22 is placed on the diode mounting surface on the surface of the second base member 56, soldered, and mounted on the second heat sink base material 55B. Next, the second heat sink base material 55B is bent into an arc shape. Therefore, as shown in FIG. 11B, the second base member 56 is bent at the first concave groove 44 and the second concave groove 45 and bent into a cylindrical body having a substantially arc-shaped cross section. A second heat sink base 34 is obtained. As a result, a second heat sink assembly in which the negative-side diode 22 is mounted on the second heat sink 33E is obtained.

  According to the sixth embodiment, in the bending process of the second heat sink base material 55B, the second base member 56 is easily bent at the first concave groove 44 and the second concave groove 45, so that the bending work is easy. In addition, the stress acting on the solder joint in the bending process is reduced, and the joining reliability of the negative-side diode 22 with respect to the second heat sink base 34 is improved.

  Here, also in the first heat sink base material, the first and second concave grooves are similarly formed in the first base member, and the bending process of the first heat sink base material becomes easy.

Embodiment 7 FIG.
FIG. 12 is a side view showing a second heat sink assembly of the rectifier mounted on the automotive alternator according to Embodiment 7 of the present invention.

In FIG. 12, the second heat sink base 34 is bent at a right angle at two bending portions and formed into a cylindrical body having a U-shaped cross section. And the fixed lug 36 is formed in three places, the both ends of the 2nd heat sink base 34, and the bottom center part. The heat radiating fins 35 are erected vertically on the outer peripheral wall surface of the second heat sink base 34. Further, at the bent portion of the second heat sink base 34, the radiation fins 35 are formed radially. In addition, first concave grooves 44 whose width direction is the groove direction are formed in each bent portion of the second heat sink base 34. Two negative-side diodes 22 are arranged on the inner peripheral wall surface of each U-shaped side of the second heat sink base 34, and the copper base 24 is soldered and mounted to produce the second heat sink 33F. Here, since the first heat sink is also manufactured in the same manner, the description thereof is omitted.
Other configurations are the same as those in the first embodiment.

  In order to fabricate the second heat sink 33F configured as described above, first, the first concave groove 44 is formed in a portion that divides the surface of the second base member 56 shown in FIG. A heat sink base material recessed so as to extend in the width direction is prepared. Next, the negative diode 22 is placed on the diode mounting surface on the surface of the second base member and soldered. Thereafter, the second base member is bent at a right angle at the first concave groove 44 to obtain the second heat sink 33F.

According to the seventh embodiment, the second heat sink 33F is bent into a cylinder with a polygonal cross section having two corners, and the first heat sink is also produced in the same manner as the second heat sink 33F. Therefore, since the first and second heat sinks can be disposed extending in the circumferential direction in the space surrounding the shaft 18 in the rear bracket 3, the heat radiation area can be increased as in the first embodiment, The cooling performance of the first and second heat sinks can be enhanced.
In addition, since the first concave groove 44 is formed in the surface of the bent portion of the second base member, the work of bending the second heat sink base material is facilitated and the bending force is reduced, so that the second heat sink 33F Reliability is improved. In addition, the stress acting on the solder joint in the bending process is reduced, and the joining reliability of the negative-side diode 22 to the second heat sink base 34 is improved.

  In the seventh embodiment, the second heat sink base material is bent at right angles at two locations in the length direction to produce the second heat sink 33F. However, there are two bent portions of the second heat sink base material. For example, four locations may be used. In this case, for example, if the first heat sink base material is divided into five equal parts in the length direction, the first concave grooves are formed and bent so that the inner angle is 135 degrees at each first concave groove forming portion. Good.

Embodiment 8 FIG.
FIG. 13 is a view for explaining the configuration of the second heat sink assembly of the rectifier mounted on the automotive alternator according to Embodiment 8 of the present invention. FIG. 13 (a) shows the fixed state of the negative diode. FIG. 13B is a cross-sectional view showing a fixed state of the negative electrode side diode, and FIG. 13C is an exploded view of the second heat sink assembly.

In FIG. 13, the copper base 24A of the negative-side diode 22A has a length longer than the width of the second heat sink base 34, and is formed into a U shape with its both ends protruding downward. The negative electrode side diode 22A is placed between a pair of fixing ribs 42 of the second heat sink base 34 by protruding the flange portions 46 of the copper base 24A from the both ends in the width direction of the second heat sink base 34 to the back surface side. It is caulked and fixed by the fixing rod 42 and mounted on the second heat sink 33A. The flange 46 constitutes an axial movement restricting portion. Here, since the first heat sink is also manufactured in the same manner, the description thereof is omitted.
Other configurations are the same as those in the second embodiment.

According to the eighth embodiment, the copper base 24A of the negative electrode side diode 22A is formed in a U shape. Accordingly, when the negative electrode side diode 22A is placed on the diode mounting surface of the second base member of the second heat sink base material, the copper base 24A moves in the length direction of the second base member by the pair of fixing rods 42. Is restricted, and the flange portion 46 extends from both sides of the second base member in the width direction to the back surface side, and movement of the negative diode 22 in the width direction of the second base member is restricted.
Thereby, the fall and drop-off of the negative electrode side diode 22 when the second heat sink base material on which the negative electrode side diode 22 is placed are transported in the production line are suppressed, and the productivity is improved.

Embodiment 9 FIG.
FIG. 14 is a cross-sectional view of the main part showing the periphery of the rectifier of the automotive alternator according to Embodiment 9 of the present invention.

In FIG. 14, the rear side of the first heat sink base 28 bent into a cylindrical body having a circular arc cross section of the first heat sink 27 </ b> G extends toward the inner end face side of the rear bracket 3 with respect to the radiation fin 29. The rear-side extending portion 47 of the first heat sink base 28 is formed in a tapered shape in which the radial position of the outer peripheral surface gradually decreases toward the rear side. In addition, the rear side of the second heat sink base 34 that is bent and formed into a cylindrical body having a circular arc cross section of the second heat sink 33G extends toward the inner end face side of the rear bracket 3 with respect to the heat radiating fins 35. The rear-side extending portion 48 of the second heat sink base 34 is formed in a tapered shape in which the radial position of the outer peripheral surface gradually decreases toward the rear side. The extending parts 47 and 48 constitute a cooling air guide part. An intake hole 3a is formed in the rear bracket 3 so as to face the first and second heat sinks 27G and 33G.
Other configurations are the same as those in the first embodiment.

  According to the ninth embodiment, the intake hole 3a is formed in the rear bracket 3 so as to face the first and second heat sinks 27G and 33G, and the first and second heat sink bases 28 and 34 extend. The portions 47 and 48 are formed in a tapered shape. Therefore, the cooling air sucked from the intake holes 3a flows between the radiating fins 29 and 35 along the inclined surfaces (outer peripheral wall surfaces) 47a and 48a of the extending portions 47 and 48. Thereby, the cooling air sucked from the intake holes 3a efficiently flows between the radiation fins 29 and 35, and the cooling performance of the first and second heat sinks 27G and 33G is improved.

Embodiment 10 FIG.
FIG. 15 is a cross-sectional view of the main part showing the periphery of the rectifier of the automotive alternator according to Embodiment 10 of the present invention.

In FIG. 15, the positive and negative side diodes 21B and 22B have a copper base 24B longer than the widths of the first and second heat sink bases 28 and 34, and project both ends radially outward. It is molded into a U shape. The rear side flange 49 of the copper base 24B is formed in a tapered shape in which the radial position of the outer peripheral surface gradually decreases from the position of the outer peripheral wall surface of the first and second heat sink bases 28, 34 toward the rear side. ing. The flange portion 49 constitutes a cooling air guide portion. An intake hole 3 a is formed in the rear bracket 3 so as to face the first and second heat sinks 27 and 33.
Other configurations are the same as those in the first embodiment.

  According to the tenth embodiment, the intake hole 3a is formed in the rear bracket 3 so as to face the first and second heat sinks 27, 33, and the copper base 24B of the positive side and negative side diodes 21B, 22B. The collar portion 49 is formed in a tapered shape. Therefore, the cooling air sucked from the intake hole 3 a flows between the heat radiation fins 29 and 35 along the inclined surface (outer peripheral wall surface) 49 a of the flange portion 49. Thereby, the cooling air sucked from the intake holes 3a efficiently flows between the radiation fins 29 and 35, and the cooling performance of the first and second heat sinks 27 and 33 is improved.

Embodiment 11 FIG.
FIG. 16 is a side view for explaining a method of manufacturing the second heat sink assembly of the rectifier mounted on the automotive alternator according to Embodiment 11 of the present invention. FIG. The state before mounting is shown, and FIG. 16B shows the state after mounting the negative-side diode.

In the eleventh embodiment, as shown in FIG. 16A, positioning concave grooves 58 are formed on the surface of the second base member 56 of the second heat sink base material 55C so as to be long between the fixed lugs 36, respectively. Three recesses are provided in the vertical direction at a predetermined pitch. Each positioning groove 58 is recessed over the entire region in the width direction of the second base member 56 with a predetermined groove width and a predetermined depth, and constitutes a diode mounting surface.
Then, as shown in FIG. 16B, the negative-side diode 22 is placed in each positioning groove 58, and the copper base 24 is soldered and mounted.
Next, although not shown, a second heat sink assembly in which the second base member 56 is bent in an arc shape so that the surface of the second base member 56 is on the inner diameter side, and the negative diode 22 is mounted on the second heat sink. obtain.

  According to the eleventh embodiment, since the positioning groove 58 is recessed in the surface of the second base member 56, the negative electrode diode 22 can be obtained simply by placing the negative electrode diode 22 in the positioning groove 58. Can be positioned while restricting movement in the length direction. Therefore, the soldering work of the negative electrode side diode 22 becomes easy.

  Here, also in the first heat sink base material, the positioning concave grooves are similarly formed on the surface of the first base member, and the soldering work of the positive diode is facilitated.

In each of the above embodiments, the positive diode is mounted on the first heat sink disposed on the inner diameter side, and the negative diode is mounted on the second heat sink disposed on the outer diameter side. The diode may be mounted on a second heat sink disposed on the outer diameter side, and the negative diode may be mounted on a first heat sink disposed on the inner diameter side.
Further, the axial lengths of the first and second heat sinks do not necessarily have to be the same, and the number of radiating fins and the fin pitch may be set as appropriate.

  In each of the above embodiments, the positive-side diode and the negative-side diode are mounted on the inner peripheral wall surfaces of the first and second heat sink bases. However, the positive-side diode and the negative-side diode are the first and second diodes. It may be mounted on the outer peripheral wall surface of the heat sink base, the positive diode may be mounted on the outer peripheral wall surface of the first heat sink base, and the negative diode may be mounted on the inner peripheral wall surface of the second heat sink.

  In each of the above embodiments, the three-phase AC winding is described as being Y-connected. However, even if the three-phase AC winding is Δ-connected, the same effect can be obtained. In each of the above embodiments, six positive side and negative side diodes are mounted on each of the first and second heat sinks. However, the positive electrode mounted on each of the first and second heat sinks. The number of side and negative side diodes is not limited to six. For example, when the stator coil is composed of a set of three-phase AC windings and the output of the three-phase AC windings is full-wave rectified by a diode bridge, the positive electrodes mounted on the first and second heat sinks, respectively. The number of side and negative side diodes is three. Also, when the stator coil is composed of a set of three-phase AC windings, and in addition to the three output terminals of the three-phase AC windings, the output of the neutral point Y-connected is full-wave rectified with a diode bridge. The number of positive side and negative side diodes mounted on each of the first and second heat sinks is four.

  In each of the above embodiments, the first and second heat sink bases are bent and formed into a cylindrical body having a circular arc cross section. However, the first and second heat sink bases have a circular arc cross section. It is not limited to a body, and may be a cylindrical body having a cross-sectional arc shape extending in the circumferential direction in a space surrounding the shaft in the case and having a predetermined axial length. Note that the U-shaped cylindrical body having the shape of the heat sink base in Embodiment 7 described above, that is, a polygonal cylindrical body having a plurality of corners is also included in the cross-sectional arc-shaped cylinder in the present application.

  DESCRIPTION OF SYMBOLS 1 Case, 3a Intake hole, 6 Fan, 12 Stator, 13 Stator core, 14 Stator coil, 15 Rotor, 18 Shaft, 20 Rectifier, 21 Positive side diode (rectifier equipment), 22, 22A Negative side diode (Rectifying parts), 27, 27G first heat sink, 28 first heat sink base, 29 heat radiation fin, 32 positioning protrusion, 33, 33A, 33B, 33C, 33D, 33E, 33F, 33G second heat sink, 34 first heat sink base , 35 Radiation fins, 38 Positioning protrusions, 42 Fixing hooks, 43 Auxiliary heat dissipation fins, 44 1st groove (easy to bend), 45 2nd groove (easy to bend), 46 heel (Axial movement restricting part) ), 47, 48 Extension part (cooling air guide part), 49 collar part (cooling air guide part), 50 First heat sink Wood, 51 first base member, 55, 55A, 55B, 55C the second heat sink base member, 56 second base member, 58 positioning grooves.

Claims (14)

A case, a rotor fixed to a shaft pivotally supported by the case and disposed in the case; a rotor supported by the case and covering the outer periphery of the rotor; The stator wound around the stator core and the alternating current generated in the stator coil disposed on one side in the axial direction of the rotor in the case and electrically connected to the stator coil A rectifier that rectifies the current into direct current, and a fan that is fixed to an end face on one side in the axial direction of the rotor,
Each of the rectifying devices has a heat sink base formed in a cylindrical body having an arc cross section, and a plurality of radiating fins standing on at least one of an inner peripheral wall surface and an outer peripheral wall surface of the heat sink base and extending in the axial direction. Two heat sinks arranged substantially concentrically around the shaft center of the shaft and arranged in the radial direction, and spaced apart from each other in the circumferential direction on one of the inner wall surface and the outer wall surface of the heat sink base. A plurality of rectifying parts to be mounted, and
The AC heat generator for vehicles, wherein the heat sink base is formed by bending a flat base member on which the plurality of rectifying components are mounted in an arc shape.   2. The vehicular AC generator according to claim 1, wherein the rectifying component is fixed by caulking with fixing rods erected on both sides of the rectifying component in the circumferential direction of the heat sink base.   The vehicle alternator according to claim 2, wherein the rectifying component is mounted on an inner peripheral wall surface of the heat sink base and is fixed by caulking with the fixing rod when the heat sink base is bent.   4. The vehicle AC according to claim 1, wherein the radiating fin is erected on an inner peripheral wall surface and an outer peripheral wall surface of at least one heat sink base of the heat sink base. 5. Generator.   5. The bendable portion configured by reducing the thickness of the heat sink base is formed at a portion between the rectifying parts of the heat sink base. AC generator for vehicles as described in 2.   The rectifying component includes an axial movement restricting portion that engages with both side surfaces of the heat sink base in the width direction and restricts the axial movement of the rectifying component. 6. The vehicle alternator according to any one of 5 above. The intake hole is drilled in the case so as to face the heat sink in the axial direction,
A cooling air guide part for guiding cooling air sucked from the air intake holes by rotation of the fan fixed to the rotor between the heat radiating fins is at one axial end of at least one of the heat sink base and the rectifying component. The vehicular AC generator according to any one of claims 1 to 6, wherein the vehicular AC generator is formed in a portion. Each has a heat sink base made of a cylindrical body having a cross-sectional arc shape, and a plurality of heat radiation fins extending in the axial direction standing on at least one of the inner peripheral wall surface and the outer peripheral wall surface of the heat sink base. And two heat sinks arranged side by side in the radial direction, and a plurality of rectifying components mounted on one of the inner wall surface and the outer wall surface of the heat sink base so as to be spaced apart from each other in the circumferential direction. A method of manufacturing a rectifier for an AC generator for a vehicle,
Producing a heat sink base material having a flat base member having a predetermined length and a plurality of heat dissipating fins standing on at least one surface of the base member;
Mounting the rectifying component on one surface of the base member;
Bending the heat sink by bending the base member on which the rectifying component is mounted in an arc; and
The manufacturing method of the rectifier of the alternating current generator for vehicles characterized by comprising. In the step of producing the heat sink base material, a positioning groove is provided in a region where the rectifying component is mounted on one surface of the base member,
In the step of mounting the rectifying component, the rectifying component is placed in the positioning concave groove, positioned, and mounted on one surface of the base member with restricted movement in the length direction. The method for manufacturing a rectifier for an AC generator for a vehicle according to claim 8. In the step of producing the heat sink base material, fixing hooks are erected on both sides in the length direction of the region where the rectifying component is mounted on one surface of the base member,
The step of bending the heat sink is characterized in that the base member is bent in an arc shape with one surface side of the base member being the inner diameter side, and the rectifying component is caulked and fixed by the fixing hook. A method for manufacturing a rectifier for an AC generator for a vehicle according to claim 8 or 9. In the step of producing the heat sink base material, positioning protrusions are erected on both sides in the length direction of the region where the rectifying component is mounted on one surface of the base member,
In the step of mounting the rectifying component, the rectifying component is placed between the positioning protrusions, positioned, and mounted on one surface of the base member with restricted movement in the length direction. The method of manufacturing a rectifier for a vehicle alternator according to claim 8.   In the step of manufacturing the heat sink base material, an easily bendable portion having a predetermined length in the length direction and a reduced thickness over the entire width direction is provided between the regions of the base member where the rectifying component is mounted. The method of manufacturing a rectifier for a vehicle alternator according to any one of claims 8 to 11, wherein the rectifier is formed.   The rectifying component includes a pair of axial movement restricting portions, and when the rectifying component is mounted on one surface of the base member, the pair of axial movement restricting portions are arranged on both sides in the width direction of the base member. 13. The movement of the base in the width direction of the base is restricted by engaging with both side surfaces of the base member in the width direction. The manufacturing method of the rectifier of the alternating current generator for vehicles of description.   14. The vehicle according to claim 8, further comprising a step of soldering the rectifying component to one surface of the base member prior to the step of bending the heat sink. A method of manufacturing an AC generator rectifier.

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