JP3680664B2 - Magnet generator - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a magnet generator provided in an internal combustion engine (hereinafter referred to simply as “engine”) mounted on a vehicle.
[0002]
[Prior art]
Conventionally, an engine mounted on a vehicle has been provided with a magnetic generator for supplying power to a load such as a headlamp and charging a battery. In recent years, electrical loads have increased due to an increase in electrical components mounted on vehicles, and higher output of generators has been demanded. In particular, in motorcycles such as motorcycles, the electrical load is greatly increased due to the use of two headlights or electronic control of the engine fuel injection device. For this reason, higher output of the generator is required, and it is important to further reduce the size and weight.
[0003]
Therefore, by changing the permanent magnet of the rotor from a ferrite-based permanent magnet to a rare earth permanent magnet, it is possible to satisfy the demands for higher output, smaller size, and lighter generator. However, increasing the output and the size of the generator increases the amount of heat generated by the armature of the stator, resulting in a problem that the heat resistance limit of the armature is exceeded.
Accordingly, techniques for cooling the armature are disclosed in (1) Japanese Patent Laid-Open No. 61-236350, (2) Japanese Utility Model Laid-Open No. 56-20376, and (3) Japanese Patent Laid-Open No. 61-124246. ing.
[0004]
[Problems to be solved by the invention]
However, the techniques disclosed in the above publications have the following problems.
(1) According to the magnet generator disclosed in Japanese Patent Application Laid-Open No. 61-236350, radial ribs 101 are formed in the rotor 100 as shown in FIG. The rib 101 agitates the air in the rotor 100 to create an air flow. However, although the rib 101 has an effect of stirring the air, the air stirred by the rib 101 hits the rib 101, so that the position away from the hole 102 provided in the rotor 100 as shown in FIG. Flow. As a result, it is difficult to discharge the air heated by the armature from the hole 102 to the outside, and the effect of cooling the armature is reduced.
[0005]
{Circle around (2)} According to the magnet generator disclosed in Japanese Utility Model Publication No. 56-20376, a fan for creating an air flow is provided on the inner peripheral side from the hole of the rotor. Therefore, the flow of air stirred by the fan flows on the inner peripheral side of the hole, and the effect of discharging the air heated by the armature in the rotor from the hole to the outside becomes low.
(3) According to the magnet generator disclosed in Japanese Patent Laid-Open No. 61-124246, a fan for creating a flow of air is formed as a separate body and is fixed by caulking to the rotor together with the magnet. Therefore, the number of parts increases and the manufacturing cost increases.
[0006]
In addition to the magnet generators disclosed in the above-mentioned publications, the magnet generator needs to take out the generated electric power, so that the armature 110 and the lead wire 111 are connected as shown in FIG. It is connected. A portion where the armature 110 and the lead wire 111 are connected is fixed to the stator core 113 by a clip 112 with screws. As shown in FIG. 13, a groove 116 is formed in the casing 114 so that the casing 114 of the engine does not interfere with the clip 112 and the screw 115 at this fixed portion. The groove 116 secures a predetermined interval between the casing 114 and the fixed portion. By forming the groove portion 116 in the casing 114, in addition to the air flow A that flows through the peripheral portion of the armature 110 as shown in FIG. 13, air that bypasses the inner peripheral portion side of the core 113 from the groove portion 116 of the casing 114. Flow B is generated. Since the air flow B is generated, the air flow A flowing around the armature 110 is reduced, so that the cooling ability of the armature 110 is lowered.
[0007]
SUMMARY OF THE INVENTION An object of the present invention is to provide an inexpensive magnet generator that can improve the armature cooling capacity with a simple structure.
[0008]
[Means for Solving the Problems]
According to the magnet generator of the first aspect of the present invention, a plurality of holes are formed in the circumferential direction at the bottom of the bowl-shaped member, and a protrusion is provided between the holes. The protrusion is formed integrally with the hook-shaped member and protrudes from the bottom of the hook-shaped member toward the stator. The air inside the bowl-shaped member is agitated by this protrusion. The agitated air can flow around the armature and cool the armature. In addition, the protrusions are provided between the holes, and are shaped so that the cross section perpendicular to the drive shaft is circular, so that the air flow in the vicinity of the holes is not obstructed and discharged from the holes. The air flow rate can be increased. Therefore, the cooling capacity of the armature can be improved.
[0009]
Further, since the protrusion is formed integrally with the bowl-shaped member, the structure is simple and the number of parts can be reduced. Therefore, the magnet generator can be manufactured at low cost.
Furthermore, the projecting portion is positioned such that the end on the side opposite to the drive shaft is on the outer peripheral side than the end on the drive shaft side of the hole, that is, on the radially outer side of the bowl-shaped member. Therefore, the air stirred by the protrusion passes through the portion where the hole is formed, and the air heated by the armature is easily discharged from the hole to the outside of the bowl-shaped member. Therefore, the air flow around the armature is promoted, and the cooling ability of the armature can be improved.
[0010]
According to the magnet generator of claim 2 of the present invention, the plate-like member is provided on the opposite side of the bowl-like member. The plate-like member is provided, for example, in a gap between the stator and the casing on the drive shaft side of the stator so as to inhibit the flow of air flowing through the inner peripheral side of the stator. The plate-shaped member obstructs the flow of air that passes through the gap and flows on the inner peripheral side of the armature, whereby the flow rate of air flowing in the vicinity of the armature increases. Therefore, the cooling capacity of the armature can be improved.
[0011]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, a plurality of examples showing embodiments of the present invention will be described with reference to the drawings.
(First embodiment)
FIG. 1 shows a magnet generator according to a first embodiment of the present invention.
As shown in FIG. 1, the magnet generator 1 is provided inside an engine casing 2. The magnet generator 1 includes a rotor 3 as a bowl-shaped member, a permanent magnet 4, a stator 5, and a plate 6 as a plate-shaped member.
[0012]
The rotor 3 has a yoke 31 as a bottom portion, a side portion 32, and a tapered portion 33 that is fitted into a crankshaft 7 that is a drive shaft of the engine. The rotor 3 is provided on the taper portion 71 of the crankshaft 7 and is fixed to the crankshaft 7 by bolts 8 through the plate 6 from the opposite yoke side of the rotor 3. Therefore, the rotor 3 rotates together with the crankshaft 7. The rotor 3 is made of iron, and the yoke 31, the side portion 32, and the taper portion 33 are integrally formed by hot forging.
[0013]
As shown in FIG. 2, a plurality of ventilation windows 34 as holes are formed in the yoke 31 in the circumferential direction. Between each ventilation window 34, as shown in FIG. 1, the truncated cone-shaped protrusion part 35 which protrudes from the yoke 31 to the stator 5 side is formed. The protrusion 35 is formed integrally with the yoke 31 by hot forging.
[0014]
As shown in FIG. 3, the end 35 a of the protrusion 35 on the side opposite to the crankshaft 7 is located on the outer side in the radial direction of the rotor 3 than the end 34 a of the ventilation window 34 on the crankshaft 7 side. The protruding portion 35 has a trapezoidal shape in a side view as shown in FIG. 1 and a circular truncated cone shape in a plan view as shown in FIG. The shape of the protruding portion 35 is not limited to the truncated cone shape, and may be a cylindrical shape.
[0015]
As shown in FIG. 1, the permanent magnet 4 is provided on the inner peripheral side 32 a of the side portion 32 of the rotor 3. The permanent magnet 4 is a rare earth permanent magnet and is sandwiched between a spacer 41 and a spacer 42 made of a non-magnetic material. The permanent magnet 4, the spacer 41 and the spacer 42 are covered with a stainless steel magnet protection member 44. The permanent magnet 4, the spacer 41, and the spacer 42 are fixed to the rotor 3 by covering the side 32 end 32 b of the rotor 3 after being covered with the magnet protection member 44. A plurality of permanent magnets 4 are provided in the circumferential direction on the inner peripheral side of the rotor 3.
[0016]
As shown in FIGS. 1 and 4, the stator 5 has an armature 50, and the armature 50 is annularly arranged in the circumferential direction of the crankshaft 7. The armature 50 is disposed so as to face the permanent magnet 4 provided on the rotor 3. The stator 5 is fixed to the casing 2 of the engine by screws 51. The armature 50 of the stator 5 includes a core 52 and a coil wire 53 that is wound around the core 52. The core 52 is formed by laminating a core sheet 521 formed of an iron plate and a core end plate 522. The core 52 is insulated by covering the core sheet 521 and the core end plate 522 and covering with the epoxy resin 54, and then the coil wire 53 is wound around the core 52. The wound coil wire 53 is also impregnated with epoxy resin, and the coil wire 53 is fixed to the core 52.
[0017]
The stator 5 is connected to a lead wire 55 for taking out the generated electric power. The lead wire 55 is fixed to the core 52 by a screw 57 via a clip 56. In order to prevent these clips 56 and screws 57 and the casing 2 of the engine from interfering with each other, a groove 20 is formed in the casing 2.
[0018]
As shown in FIG. 1, the plate 6 is provided on the end 33 a of the tapered portion 33 of the rotor 3, that is, on the side opposite to the yoke, and is fixed to the crankshaft 7 together with the rotor 3 by bolts 8. The outer diameter of the plate 6 is formed so as to be slightly smaller than the inner diameter of the core 52 of the stator 5 arranged in an annular shape so as to inhibit the flow of air flowing through the gap 50a on the inner peripheral side of the core 52. Is provided. Therefore, the flow rate of the air that passes through the groove portion 20 and flows into the gap 50a on the inner peripheral side of the core 52 is reduced. A step 61 is formed on the plate 6 to prevent the plate 6 and the casing 2 from contacting each other.
[0019]
The operation of the magnet generator 1 configured as described above and the air flow will be described.
When the rotor 3 rotates together with the crankshaft 7 of the engine, a current is generated in the armature 50. This current causes the armature 50 to generate heat and become high temperature. The air around the armature 50 and the air inside the rotor 3 heated by the armature 50 is discharged to the outside through the ventilation window 34 and radiates heat while circulating around the outer peripheral side of the side portion 32 of the rotor 3. The air that has been radiated and cooled again enters the rotor 3 from the side opposite the yoke that is the open side of the rotor 3. The air that has entered the rotor 3 takes heat from the armature 50 when passing through the periphery of the armature 50, and is discharged from the ventilation window 34 again. That is, an air flow as shown by an arrow A in FIG. 1 is formed, and the air circulates.
[0020]
When the rotor 3 in which the protruding portion 35 is formed on the yoke 31 rotates, an air flow as shown by an arrow in FIG. 3 is formed around the protruding portion 35. By making the planar shape of the protrusion 35 circular, the flow of air stirred by the protrusion 35 circulates around the protrusion 35 and passes through the vicinity of the ventilation window 34. Therefore, the air stirred by the protrusion part 35 is easily discharged | emitted from the ventilation window 34, and the protrusion part 35 does not inhibit discharge | emission of the air from the ventilation window 34. FIG.
[0021]
Further, as shown in FIG. 3, by defining the positional relationship between the projecting portion 35 and the ventilation window 34 so that the end portion 35a of the projecting portion 35 is located outside the end portion 34a of the ventilation window 34, the projecting portion The air stirred at 35 passes through the portion where the ventilation window 34 is open. Therefore, air is easily discharged from the ventilation window 34.
[0022]
The plate 6 obstructs the air flow to the inner peripheral side of the armature 50 via the groove 20 as shown by the arrow B in FIG. That is, as indicated by the arrow A, a part of the air flow circulating from the peripheral portion of the armature 50 through the ventilation window 34, the outer peripheral side of the side portion 32 of the rotor 3, and the opening side of the rotor 3 is part of the armature 50. Prevents flow into the inner circumference. Therefore, the air around the armature 50 circulates along the arrow A, and the amount of air flowing around the armature 50 increases.
[0023]
Next, the effect of the protrusion part 35 provided in the rotor 3 of the magnet type generator 1 of 1st Example is demonstrated.
FIG. 2 shows the magnet generator 1 of the present embodiment, which is provided with a ventilation window 34 and a protrusion 35.
FIG. 5 shows the rotor 80 of the magnet generator of the first comparative example. The rotor 80 of the comparative example 1 has a ventilation window 81 and first ribs 82 provided radially between the ventilation windows 81 and extending in the radial direction of the rotor 80. Further, the rotor 80 is provided with second ribs 83 radially on the inner peripheral side of the ventilation window 81, the length of the rotor 80 in the radial direction being shorter than the diameter of the ventilation window 81.
[0024]
FIG. 6 shows a rotor 90 of the magnet generator of Comparative Example 2. In the rotor 90 of the magnet generator of Comparative Example 2, only ribs 92 whose radial length of the rotor 90 is shorter than the diameter of the ventilation window 91 are provided radially.
The temperature of each armature 50 of the magnet generator 1 having the rotor 3 of this embodiment, the magnet generator having the rotor 80 of Comparative Example 1, and the magnet generator having the rotor 90 of Comparative Example 2 is determined. A comparison is shown in FIG.
[0025]
As shown in FIG. 7, it can be seen that the magnet generator 1 of the present example is superior in the cooling capacity of the armature 50 compared to the magnet generators of Comparative Example 1 and Comparative Example 2. Compared with the magnet generator of this embodiment, the magnet generators of Comparative Example 1 and Comparative Example 2 have the armature 50 having a temperature of 10 ° C. to 15 ° C. higher than that of the magnet generator of this embodiment. It is shown that it is effective to make the protrusion 35 into a circular protrusion like a machine.
[0026]
As described above, according to the magnet generator 1 of the present embodiment, since the projecting portion 35 is formed integrally with the yoke 31 of the rotor 3, the heated air around the armature 50 can be obtained with a simple structure. Can be stirred. Moreover, the heated air can be easily discharged from the ventilation window 34 at the same time when the heated air is stirred. Furthermore, by providing the plate 6 on the side opposite to the yoke 31, the flow rate of the air circulating around the armature 50 can be increased. Therefore, the cooling capacity of the armature 50 can be increased with a simple structure.
[0027]
Further, there is no need to separately assemble a member for stirring the air inside the rotor 3 to the rotor 3, and the protrusion 35 can be formed simultaneously when the rotor 3 is formed by hot forging. Therefore, the number of parts is reduced, and the magnet generator 1 can be manufactured at low cost.
[0028]
(Second embodiment)
A second embodiment of the present invention is shown in FIG.
As shown in FIG. 8, the magnet generator of the second embodiment is different from the first embodiment in the shape of the protruding portion 36. In the second embodiment, one end 36a of the protrusion 36 is formed in a substantially V shape so that the planar shape of the protrusion 36 has a teardrop shape.
In the second embodiment, the same effect as that of the first embodiment can be obtained even if the protrusion 36 is formed into a shape as shown in FIG.
[0029]
(Third embodiment)
A third embodiment of the present invention is shown in FIG.
As shown in FIG. 9, the magnet generator of the third embodiment is different from the first embodiment in the shape of the protruding portion 37. In the third embodiment, the planar shape of the projecting portion 37 is formed so as to be substantially V-shaped at both end portions 37a and 37b.
In the third embodiment, the same effect as that of the first embodiment can be obtained even if the protrusion 37 is formed into a shape as shown in FIG.
[0030]
(Fourth embodiment)
A fourth embodiment of the present invention is shown in FIG.
As shown in FIG. 10, the magnet generator of the fourth embodiment is different from the first embodiment in the shape of the protruding portion 38. In the fourth embodiment, the projecting portion 38 is shaped so as to have a quadrilateral shape with curved corners.
In the fourth embodiment, the same effect as in the first embodiment can be obtained even if the protruding portion 38 is formed into a shape as shown in FIG.
[0031]
(5th Example)
A fifth embodiment of the present invention is shown in FIG.
As shown in FIG. 11, the magnet generator of the fifth embodiment is different from the first embodiment in the shape of the protrusion 39. In the fifth embodiment, as shown in FIG. 11, the central portion 39a of the protruding portion 39 is formed in a concave shape as compared with the peripheral portion 39b. The outer shape of the protrusion 39 may be a circular shape as in the first embodiment, or a shape as described in the second to fourth embodiments.
In the fifth embodiment, the air agitation effect is increased, and at the same time, the weight of the rotor can be reduced.
[Brief description of the drawings]
FIG. 1 is a cross-sectional view showing a magnet generator according to a first embodiment of the present invention.
2 is a view showing a rotor of the magnet generator according to the first embodiment of the present invention, as viewed from the direction of arrow II in FIG.
3 is a view showing a ventilation window and a protrusion formed in the rotor of the magnet generator according to the first embodiment of the present invention, and FIG. 3 (A) is an arrow view seen from the same direction as FIG. (B) is sectional drawing cut | disconnected by the BB line of (A).
4 is a view showing the stator of the magnet generator according to the first embodiment of the present invention, and is an arrow view seen from the same direction as FIG. 2. FIG.
5 is a view showing a rotor of a magnet generator of Comparative Example 1, and is an arrow view seen from the same direction as FIG. 2. FIG.
6 is a view showing a rotor of a magnet generator according to comparative example 2, and is an arrow view seen from the same direction as FIG. 2. FIG.
FIG. 7 is a diagram showing the influence of the magnet generator according to the first embodiment of the present invention and the magnet generator according to Comparative Example 1 and Comparative Example 2 on the temperature of the armature.
FIG. 8 is a schematic view showing a protrusion of a magnet generator according to a second embodiment of the present invention and the air flow around the protrusion.
FIG. 9 is a schematic diagram showing a protrusion of a magnet generator according to a third embodiment of the present invention and the air flow around the protrusion.
FIG. 10 is a schematic view showing a protrusion of a magnet generator according to a fourth embodiment of the present invention and the air flow around the protrusion.
FIG. 11 is a sectional view showing a protrusion of a magnet generator according to a fifth embodiment of the present invention.
12A and 12B are views showing a ventilation window and a protrusion formed in a rotor of a conventional magnet generator, where FIG. 12A is a view as seen from the same direction as FIG. It is sectional drawing cut | disconnected by the BB line of A).
FIG. 13 is a cross-sectional view showing a conventional magnet generator.
[Explanation of symbols]
1 Magnet generator 3 Rotor (saddle-shaped member)
4 Permanent magnet 5 Stator 6 Plate (plate member)
34 Ventilation window (hole)
35, 36, 37, 38, 39 Protrusion 50 Armature

Claims (2)

A hook-shaped member fixed to the drive shaft of the internal combustion engine and rotating together with the drive shaft;
A plurality of permanent magnets provided on the inner periphery of the bowl-shaped member;
A stator having an armature arranged in an annular shape facing the permanent magnet on the inner peripheral side of the bowl-shaped member, and fixed to a casing of the internal combustion engine;
A plurality of holes formed in the circumferential direction at the bottom of the bowl-shaped member;
A shape of a cross section in a direction perpendicular to the axial direction of the drive shaft is circular, and is formed integrally with the hook-shaped member so as to protrude from the bottom of the hook-shaped member to the stator side between the holes. With a protrusion,
The magnet generator according to claim 1, wherein an end of the protrusion on the side opposite to the driving shaft is located on a radially outer side of the flange-like member than an end of the hole on the driving shaft. The magnetic power generation according to claim 1, further comprising a plate-like member provided on an opposite bottom side of the flange-like member so as to inhibit a flow of air flowing through an inner peripheral side of the stator. Machine.

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