JP4235431B2 - Single-phase magnet generator - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a single-phase magnet generator that is mounted on an engine such as a motorcycle, a buggy, or a snow vehicle and is used for charging an on-board battery or supplying power to an electric device.
[0002]
[Prior art]
As a magnetic generator to be mounted on an engine such as a motorcycle, a single-phase magnetic generator is conventionally known from Patent Document 1 as described below.
[0003]
[Patent Document 1]
Japanese Patent Laid-Open No. 2001-238421
In a rotor of this type of single-phase magnet generator, a boss portion is generally provided at the center of a cup-shaped rotor body, and a rotor cylindrical portion is formed on the outer peripheral wall of the rotor body. A plurality of annular permanent magnets divided and formed are adhered along the circumference, and a cylindrical magnet protective cover is adhered to the inside of the permanent magnet. The stator is arranged inside the rotor, and is configured by winding a power generation coil around each salient pole portion formed on the outer peripheral portion of the stator core corresponding to the permanent magnet on the rotor side. In addition, this type of single-phase magnet generator is installed in a limited space inside the casing of the engine, so there is a strong demand for downsizing, while on the other hand, to improve the battery charging performance when the engine is idling. In addition, there is a strong demand for an increase in output current in a low-speed rotation region.
[0005]
[Problems to be solved by the invention]
Incidentally, in the output current characteristics of the magnet generator, the coil current flows in accordance with the speed at which the power generating coil cuts the magnetic flux generated by the magnet of the rotor, so that the current value in the low rotation region inevitably decreases. However, as a magnet generator mounted on the engine, even in a low engine speed range, the generated current is used for charging the on-board battery and supplying power to the electrical equipment. An output current in a low rotation region is required, and this type of magnet generator is usually designed so that the output current in the low rotation region has a predetermined current value.
[0006]
However, simply increasing the number of windings of the power generation coil of the stator, or using a large permanent magnet of the rotor or using a rare earth magnet with excellent performance, etc., will inevitably increase the output current characteristics. The output current at increases. For this reason, it is necessary to perform useless processing such as cutting and outputting a high current region by a regulator connected to the output circuit, and since the output current in the high rotation region increases, the temperature of the power generation coil is reduced. There is a possibility that problems such as excessive rise and short life of the coil wire may occur.
[0007]
The present invention has been made in view of the above points, and an object of the present invention is to provide a single-phase magnet generator capable of increasing the output current in the low rotation range while suppressing the output current in the high rotation range. And
[0008]
[Means for Solving the Problems]
In order to achieve the above object, a single-phase magnet generator according to claim 1 of the present invention has a rotor cylindrical portion formed on the outer peripheral wall of a rotor body formed in a cup shape by providing a boss portion at the center. A rotor in which a permanent magnet is arranged on the circumference inside a cylindrical portion to form a plurality of magnetic poles, and a power generation coil is wound around the plurality of salient pole portions projecting from the stator core, and the tip of the salient pole portion In a single-phase magnet generator in which the rotor is rotationally driven by the engine , the mechanical angle between the salient pole portions of the stator being 45 degrees The stator has eight poles, the mechanical angle between the magnetic poles of the rotor is 15 degrees, and the rotor has 24 poles .
[0009]
Here, in the single-phase magnet generator configured as described above, as in the invention of claim 2, the mechanical angle between the salient pole portions of the stator is set to 36 degrees, the number of poles is set to 10 poles, The mechanical angle between the magnetic poles can be set to 12 degrees, and the number of rotor poles can be 30 . Further, as in the invention of claim 3, the mechanical angle between the salient pole portions of the stator is set to 60 degrees, the number of poles is set to 6, and the mechanical angle between the magnetic poles of the rotor is set to 20 degrees. The number of poles of the rotor can be 18 poles.
[0010]
[Action]
In a single-phase magnet generator having such a configuration, a rotor is driven to rotate by an engine, and a magnetic flux is generated between a permanent magnet and a stator core mounted on the inner side of the rotor as the rotor rotates. When the power generation coil cuts the magnetic flux, an induced electromotive force is generated in the power generation coil, and power generation is performed. At this time, the number of magnetic poles of the rotor is three times as large as the number of magnetic poles of the stator, the permanent magnets on the circumference of the rotor are subdivided, and the shape of the permanent magnets of each magnetic pole is smaller than the conventional one Therefore, the output current in the intermediate rotation range to the high rotation range is lower than that of the conventional type compared to the magnet generator with the same number of poles of the stator and rotor and the same number of windings of the power generation coil of the salient pole part. Can be suppressed.
[0011]
On the other hand, since the number of poles of the rotor magnetic pole is three times that of the stator, this single-phase magnet generator has an output frequency higher than that of the conventional stator and rotor with the same number of poles. Since the output voltage is increased and the output voltage proportional to the frequency is also increased, the output current in the low rotation range is increased from the conventional one. Therefore, according to the single-phase magnet generator, the output current in the low rotation range can be increased while suppressing the output current in the high rotation range. This reduces the burden on the regulator for current adjustment connected to the output side of the generator, improves the battery charging performance when the engine is idling, etc. It is possible to extend the life of the coil wire and the like by suppressing the excessive temperature rise.
[0012]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, embodiments of the present invention will be described with reference to the drawings. FIG. 1 shows a central longitudinal section of a single-phase magnet generator, and FIG. 2 shows a front view with a partial section thereof. The main body of the rotor 1 located on the outer peripheral portion of the generator is formed into a substantially cup shape by hot forging, cutting, or the like using a magnetic metal material.
[0013]
A boss portion 4 is formed at the center of the main body of the rotor 1, a tapered hole 4 a is formed in the boss portion 4 to be fitted to the crankshaft of the engine, and a flat fastening seat surface is formed at the tip of the boss portion 4. 4b is provided, and a screw 4c is provided on the outer peripheral portion of the boss portion 4 for screwing when the rotor 1 is pulled out. A rotor cylindrical portion 3 is formed on the outer peripheral wall of the main body of the rotor 1, and a rotor bottom portion 5 is integrally formed between the rotor cylindrical portion 3 and the boss portion 4.
[0014]
A permanent magnet 2 made of a rare earth magnet is attached to the inner peripheral surface of the rotor cylindrical portion 3. As will be described later, the rare earth permanent magnet 2 is divided into 24 pieces, and as shown in FIG. 2, S-pole magnets 2a and N-pole magnets 2b are alternately arranged, and the rotor is formed into an annular shape as a whole. It is attached inside the cylindrical portion 3. These 24 permanent magnets 2 (S-pole magnet 2a and N-pole magnet 2b) form the magnetic poles of the rotor 1, and the number of magnetic poles of the rotor 1 is 24. Since 24 permanent magnets 2 (S pole magnet 2a and N pole magnet 2b) are arranged at equal intervals on the circumference to form magnetic poles, the mechanical angle of each magnetic pole is 360 degrees / 24 = 15 degrees. It has become.
[0015]
The permanent magnet 2 composed of the S-pole magnet 2 a and the N-pole magnet 2 b is arranged with a certain gap between each other, is held from the inside by a magnet protection cover 6, and is fitted into the rotor cylindrical portion 3. In order to position the permanent magnet 2, an annular non-magnetic (synthetic resin) spacer 7 is disposed between the permanent magnet 2 and the bottom portion on the bottom side inside the rotor cylindrical portion 3. A similar spacer 8 is also disposed between the permanent magnet 2 and the caulking portion 3b on the front end side of the rotor cylindrical portion 3. The spacer 7 on the bottom side is disposed so as to close the annular space from the inside of the rotor.
[0016]
The magnet protective cover 6 is formed in a cylindrical shape by punching a thin plate of a non-magnetic metal such as stainless steel into a ring shape, and a flange-like end portion is formed at the tip portion so as to cover the end surface on the tip side of the permanent magnet 2. Has been. On the other hand, a caulking portion 3b for caulking and fixing the flange-like end portion of the magnet protective cover 6 is formed at the tip of the rotor cylindrical portion 3 with a reduced thickness. When assembling the permanent magnet 2 and the magnet protective cover 6 together with the spacers 7 and 8 into the rotor cylindrical portion 2 of the main body, the magnet protective cover 5 having a plurality of permanent magnets 2 mounted on the outer peripheral portion together with the spacers 7 and 8 The rotor cylindrical portion 3 is press-fitted into a fixed position and assembled, and finally the caulking portion 3b at the tip of the rotor cylindrical portion 3 is caulked inward and fixed.
[0017]
Thus, the 24 permanent magnets 2 (the S-pole magnet 2a and the N-pole magnet 2b) are arranged on the circumference of the rotor 1, and the number of magnetic poles of the rotor 1 is 24. The number of poles of the magnetic poles of the rotor 1 is set so that salient pole parts 12 of the stator 10 to be described later have eight poles and three times the eight poles.
[0018]
On the other hand, the stator 10 is configured by winding a power generation coil 13 around eight salient pole portions 12 projecting from an outer peripheral portion of a stator core 11. As shown in FIG. 2, the stator core 11 formed by laminating a large number of core plates 11a formed by punching a steel plate into a predetermined shape has eight salient pole portions 12 on the outer periphery of the ring-shaped yoke portion. End plates 11b are disposed on the outermost sides on both sides of a large number of core plates 11a that are formed to project radially at an angular interval of 45 degrees.
[0019]
The end plate 11b basically has substantially the same shape as the core plate 11a, but its tip is bent outward to form a flange shape in order to hold the wound power generation coil 13. ing. The laminated core plate 11a and end plate 11b are caulked and fixed integrally by inserting a rivet 14 into a hole formed in the ring-shaped yoke portion.
[0020]
Then, after the surface of each salient pole portion 12 is coated with an epoxy resin, the power generation coil 13 is wound by a predetermined number of turns. A power generating coil 13 is wound around each adjacent salient pole portion 12 in the opposite direction, and each adjacent salient pole portion 12 generates a reciprocal magnetic pole (S pole, N pole). A magnetic flux in the reverse direction is formed through the circuit 12. Therefore, when the relationship between the rotor 1 and the stator 10 is as shown in FIG. 2, for example, when the first salient pole portion 12 faces the S pole of the rotor 1, the second salient pole portion 12 is the rotor 1. It is comprised so that it may oppose N pole of these.
[0021]
By the way, when the conditions necessary for the power generation operation of the rotor 1 and the stator 10 are taken into account, for example, when the number of poles of the stator is 8 and the number of poles of the rotor is twice, that is, 16 poles, When 16 magnetic poles made of magnets are repeatedly arranged on the circumference, S poles and N poles, the eight salient pole parts of the stator face the same S poles or N poles of the rotor, which is necessary as a generator. Thus, no reciprocal magnetic poles are generated at each adjacent salient pole portion, and power generation becomes impossible.
[0022]
Such a phenomenon is the same when the number of poles of the rotor is four times that of the poles of the stator, and power generation becomes impossible. Therefore, a single-phase magnet generator in which the number of rotor poles is three times the number of stator poles as in the present embodiment with the above configuration, and the conventional number of rotor poles equal to the number of stator poles. In the single-phase magnet generator, power generation is possible.
[0023]
The stator 10 having the above configuration is fastened and fixed at a predetermined position inside an engine casing (not shown) by inserting a fixing bolt into an attachment hole of a ring-shaped yoke portion of the stator core 11. On the other hand, the rotor 1 covers the outer peripheral portion of the stator 10 at the tip of the crankshaft of the engine (not shown), and the inner peripheral surface of the magnet protective cover 6 on the inner peripheral portion of the rotor cylindrical portion 3 and the salient pole portion 12 of the stator core. It is clamped and fixed in a state in which a predetermined slight gap is formed between the tip end of each of the two.
[0024]
In the single-phase magnet generator configured as described above, the rotor 1 is rotationally driven by the engine, and the permanent magnet 2 mounted inside the rotor 1 and the salient poles 12 of the stator core 11 of the stator 10 as the rotor 1 rotates. Magnetic flux is generated between the tips, and the power generating coil 13 of the stator 10 that rotates relatively cuts the magnetic flux, whereby an induced electromotive force is generated in the power generating coil 13 to generate power.
[0025]
FIG. 3 shows a graph of output current characteristics measured when an operation test of the single-phase magnet generator of the present embodiment and the conventional single-phase magnet generator is performed. As described above, the single-phase magnet generator according to the present embodiment has eight stator poles and three rotor poles, which is three times that of the stator. Is a single-phase magnet generator with 8 poles and the same number of poles as the rotor. From the graph showing the output current characteristics of FIG. 3, the generator of the present embodiment has a lower output current from the intermediate rotation range to the high rotation range, compared to the conventional single-phase magnet generator. It can be seen that the output current increases in the low rotation range, and the generated current is output from the lower rotation range.
[0026]
As a reason for this, in the single-phase magnet generator of the present embodiment, the number of poles of the permanent magnet 2 of the rotor 1 is three times the number of poles of the stator 10, and the permanent magnet 2 is subdivided. Since the shape of the permanent magnet 2 (N-pole magnet 2a, S-pole magnet 2b) of each magnetic pole is smaller than the conventional one, the number of turns of the power generation coil in the salient pole part is the same as the number of poles of the conventional stator and rotor. Compared to the same magnet generator, the output current in the entire rotation range can be kept lower than the conventional one.
[0027]
Moreover, since the number of poles of the permanent magnet 2 of the rotor 1 is three times as large as the number of poles of the stator 10 in this single-phase magnet generator, the output frequency increases and the output is proportional to the frequency. Since the voltage also increases, the output current in the low rotation range increases from the conventional one.
[0028]
Thus, according to this single-phase magnet generator, the output current in the low rotation range can be increased while suppressing the output current in the high rotation range, and the excessive temperature rise of the power generation coil 13 can be suppressed. In addition, the life of the coil wire can be extended.
[0029]
In the above embodiment, the mechanical angle between the salient pole portions 12 of the stator 10 is 45 degrees, the number of poles of the stator 10 is 8, and the mechanical angle between the magnetic poles of the rotor 1 is 15 degrees. Although the number is 24, as another example, for example, the number of salient poles of the stator may be 10 and the number of poles of the rotor may be 30. In this case, the mechanical angle between the salient pole portions of the stator is 36 degrees, and the mechanical angle between the magnetic poles of the rotor is about 12 degrees. In addition, the number of poles of the stator salient poles may be 6 and the number of poles of the rotor magnetic poles may be 18. In this case, the mechanical angle between the salient poles of the stator is 60 degrees, The mechanical angle between the magnetic poles is 20 degrees.
[0030]
【The invention's effect】
As described above, according to the single-phase magnet generator of the present invention, the number of poles of the rotor is three times that of the stator, and the permanent magnets on the circumference of the rotor are subdivided. Because the shape of the permanent magnet of each magnetic pole is smaller than the conventional one, compared to the conventional magnet generator with the same number of poles of the stator and rotor and the number of turns of the power generation coil of the salient pole part, The output current in the entire rotation range can be kept lower than the conventional one. In addition, since the number of poles of the rotor magnetic pole is three times as large as the number of poles of the stator, the output frequency increases compared to the conventional stator and rotor having the same number of poles, and the output voltage is proportional to the frequency. Therefore, the output current in the low rotation range is increased as compared with the conventional one. Therefore, according to this single-phase magnet generator, the output current in the low rotation range can be increased while the output current in the high rotation range is suppressed, and the excessive temperature rise of the power generation coil can be suppressed. Etc. can extend the service life.
[Brief description of the drawings]
FIG. 1 is a central longitudinal sectional view of a rotor and a stator of a single-phase magnet generator showing an embodiment of the present invention.
FIG. 2 is a front view with a partial cross-section AA of the rotor and stator of the same generator.
FIG. 3 is a graph showing a comparison between output current characteristics of a conventional single-phase magnet generator and the single-phase magnet generator of the present invention.
[Explanation of symbols]
1-rotor 2-permanent magnet 2a-S-pole magnet 2b-N-pole magnet 3-rotor cylindrical portion 4-boss portion 6-magnet protective cover 7-spacer 10-stator 11-stator core 12- salient pole portion 13-generating coil

Claims (3)

A rotor cylindrical portion is formed on the outer peripheral wall of a rotor body formed in a cup shape by providing a boss portion at the center, and a rotor having permanent magnets arranged on the circumference inside the rotor cylindrical portion and a stator core protrudingly provided. A stator in which a power generation coil is wound around a plurality of salient pole portions, and a tip end portion of the salient pole portion is arranged to face a permanent magnet of the rotor , and the rotor is rotated and driven by an engine. In the phase magnet generator,
The mechanical angle between the salient poles of the stator is 45 degrees, the number of poles of the stator is 8 poles, the mechanical angle between the magnetic poles of the rotor is 15 degrees, and the number of poles of the rotor is 24 poles. A single-phase magnet generator. A rotor cylindrical portion is formed on the outer peripheral wall of a rotor body formed in a cup shape by providing a boss portion at the center, and a rotor having permanent magnets arranged on the circumference inside the rotor cylindrical portion and a stator core protrudingly provided. A stator in which a power generation coil is wound around a plurality of salient pole portions, and a tip end portion of the salient pole portion is arranged to face a permanent magnet of the rotor, and the rotor is rotated and driven by an engine. In the phase magnet generator,
The mechanical angle between each salient pole part of the stator is 36 degrees, the number of poles of the stator is 10 poles, the mechanical angle between the magnetic poles of the rotor is 12 degrees, and the number of poles of the rotor is 30 poles. A single-phase magnet generator. A rotor cylindrical portion is formed on the outer peripheral wall of a rotor body formed in a cup shape by providing a boss portion at the center, and a rotor having permanent magnets arranged on the circumference inside the rotor cylindrical portion and a stator core protrudingly provided. A stator in which a power generation coil is wound around a plurality of salient pole portions, and a tip end portion of the salient pole portion is arranged to face a permanent magnet of the rotor, and the rotor is driven and rotated by an engine. In the phase magnet generator,
  The mechanical angle between the salient pole parts of the stator is 60 degrees, the number of poles of the stator is 6 poles, the mechanical angle between the magnetic poles of the rotor is 20 degrees, and the number of poles of the rotor is 18 poles. A single-phase magnet generator.

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