JPH08205497A - Ac generator for vehicle - Google Patents

Abstract

PURPOSE: To simplify a circuit of a voltage regulator and prevent discharging of a battery by eliminating an L-terminal of an AC generator for vehicle. CONSTITUTION: A stator 8 is fixed to the interior of a housing 11 and a shaft 1 is supported by a bearing 2. Within the housing 11, a voltage regulator 12 for adjusting an amplitude of an induced voltage generated by a stator coil 9 and a rectifying diode 13 for rectifying the AC induced voltage are arranged. Moreover, in the structure where a permanent magnet is arranged at a part of the rotor 7, the housing is provided only with a B-terminal for connecting a positive electrode of a battery and the earth terminal for connecting a negative electrode. Thereby, since the initial energization mode of the voltage regulator can be eliminated, the circuit required for initial energization can be ruled out to simplify the structure of the voltage regulator.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an automotive vehicle AC generator, and more particularly to an automotive vehicle AC generator suitable for improving output by providing a permanent magnet in the field.

[0002]

2. Description of the Related Art As disclosed in Japanese Examined Patent Publication No. 6-7733, in the conventional device, does the vehicle alternator operate normally until the engine is started in conjunction with the key switch? In order to judge whether or not the charge lamp was turned on, an initial exciting current was passed through the field coil.
Therefore, in addition to the B terminal and the E terminal, it is necessary to provide an L terminal for controlling the lighting of the charge lamp in the main body of the vehicle alternator.

[0003]

In the above-mentioned prior art, the charge lamp is turned on until the engine is started, and the initial exciting current is supplied to the field coil through the semiconductor element.
When the number of rotations of the generator increased and the generated voltage reached a predetermined value, the charge lamp was turned off. Therefore, since a constant current is applied to the field coil, there are problems such as a rise in the temperature of the rotor of the vehicle alternator and discharge of the battery.

Further, there is a problem in that the circuit of the voltage regulator needs an oscillation circuit or the like for controlling the current of the initial excitation, which complicates the circuit.

Furthermore, while the initial exciting current is being applied,
It was necessary to turn on the charge lamp to warn the driver. Further, since a lamp current of about 0.5 A is required, there is a problem that the chip area of the IC of the lamp driving portion provided in the voltage regulator becomes large and the cost becomes high.

It is an object of the present invention to omit the L terminal of an automotive alternator, simplify the circuit of the voltage regulator and prevent over-discharge of the battery.

[0007]

SUMMARY OF THE INVENTION The present invention is a ground for connecting a B terminal for connecting a positive electrode of a battery and a negative electrode for connecting to a positive electrode of a battery in a housing holding a stator and rotatably holding a rotor. This is achieved by a vehicle alternator characterized by comprising only terminals.

[0008]

The direction of the magnetic flux produced by the permanent magnets arranged inside the rotor of the vehicle alternator is arranged in parallel or in series with the magnetic flux produced by the field coil, so that no current flows through the field coil. Also, the magnetic flux can be crossed to the stator coil, and the induced voltage according to the speed of the rotor can be obtained.

[0009]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS One embodiment of the present invention will be described below with reference to FIGS. FIG. 1 shows the overall configuration of the alternator of the present invention.

In the figure, a shaft 1 is provided with a pulley 3 at one end and a slip ring 4 at the other end. A brush 5 is slidably attached to the slip ring 4, and electric power can be supplied to a field coil 6 wound around a yoke 18 arranged inside the rotor 7.

Further, the rotor 7 is provided with built-in fans 10 on the left and right of the rotor 7 for obtaining an air volume proportional to the speed of the rotor 7. A stator 8 is arranged with a slight gap from the rotor 7, and a stator coil 9 is wound around the stator 8. The stator 8 is fixed inside the housing 11, and is supported by the bearing 2 with respect to the shaft 1 described above. Inside the housing 11 is a stator coil 9
A voltage regulator 12 for adjusting the magnitude of the induced voltage generated in 1 and a rectifier diode 13 for rectifying the alternating induced voltage are arranged. In addition, the permanent magnet 15 is arranged in a part of the rotor 7. Rectifier diode 1
From 3 B connected to the positive electrode of the battery 101
It is composed of a terminal 16 and a ground terminal 17 connected to the negative electrode of the battery 101.

Next, the operation will be described. In a general vehicular AC generator, a claw-shaped magnetic pole of the rotor 7 can be alternately configured with N poles and S poles by passing a current through the field coil 6. Then, the magnetized claw-shaped magnetic poles are rotated by the rotation of the engine, so that three-phase induced voltages are generated in the stator coil 9. The rectifier diode 13 rectifies this AC voltage and converts it into a DC voltage.

Further, the voltage regulator 12 controls the field current in order to maintain the DC voltage at a constant voltage of about 14.3V. By arranging the permanent magnet 15 in a part of the rotor 7 as shown in FIG. 1, magnetic fluxes are crossed in the stator coil 9 to generate an induced voltage even when the field current is zero.

Next, the voltage regulator 1 will be described with reference to FIGS. 2 and 3.
2 will be described. (It should be noted that the same reference numerals are used for the parts having the same effects as those of FIG. 1.) The battery 101 is connected to the rectifying diode 13 arranged inside via the B terminal 16 and the ground terminal 17 of the vehicle alternator 100. Has been done. The ground terminal 17 is electrically connected to the housing 11 described above. The three-phase output terminal of the stator coil 9 arranged inside the vehicle alternator is connected to the rectifier diode 13, and one phase thereof is connected to the voltage regulator 12 as the rotation speed detection signal line 103. It Further, the voltage regulator 12 is connected with a power generation voltage detection signal line 106 so that the power generation voltage of the vehicle AC generator can be detected.

The field coil 6 has a battery 1 on one side.
01 is connected to the positive terminal and the other is the voltage regulator 12
Is connected to the transistor provided inside.

In FIG. 3, the transistor for adjusting the field current arranged inside the voltage regulator 12 is an H-type bridge, and the direction of the current flowing through the field coil 6 is the permanent magnet 1.
5, the magnetomotive force can be generated in either the direction of increasing or demagnetizing. That is,
By providing the permanent magnet 15 on the rotor 7, the induced voltage by the permanent magnet 15 does not exceed the electrical withstand voltage of the rectifier diode 13 in the reverse direction when the rotational speed of the vehicle alternator 100 becomes high. The field current is controlled so that it can be protected.

Next, the operation will be described with reference to FIG.

The voltage regulator 12 includes a generated voltage detection signal line 1
The power supply voltage is always supplied by 06. Therefore, when the engine starts, a three-phase AC voltage is generated in the stator coil 9. One phase of the three-phase winding is the rotation speed detection signal line 103
Since it is connected to the voltage regulator 12 as, the voltage regulator 12 calculates the number of revolutions of the engine and the vehicle alternator from the size or the number of pulses of the number-of-revolutions detection signal line 103. Then, the size of the generated voltage detection signal line 106 is detected, and when the number of rotations exceeds a predetermined value, the current flowing through the field coil 6 is controlled. By this operation, the battery voltage is charged at about 14.3V.

According to the present invention, since the induced voltage can be generated in the stator coil 9 by the magnetic flux of the permanent magnet even if the above-mentioned initial exciting current is omitted, the rotational speed of the vehicle alternator is detected. The initial excitation mode of the voltage regulator can be omitted. Therefore, an oscillator for initial excitation, a timer, etc. can be omitted.

The above description can be expressed in a flowchart as shown in FIG. A conventional example is shown on the left side, and the present invention is shown on the right side. As can be seen from the comparison, the operation can be performed without any problem even if the initial excitation mode is omitted. Also, when it is necessary to inform the driver whether the vehicle alternator is generating electricity or not, the host computer that controls the entire vehicle (not shown) constantly monitors the battery voltage. Therefore, if the battery voltage drops, the driver can be provided with a function of blinking the display lamp or the like, and the same function as the conventional one can be achieved.

FIGS. 5 to 7 show the arrangement structure of the permanent magnets 15 arranged on the rotor 7.

FIG. 5 shows a structure in which the permanent magnets 15 are arranged so as to fill the space between the adjacent claw-shaped magnetic poles 14.

Further, in FIG. 6, a permanent magnet 15 is arranged at the end magnetic pole of the claw-shaped magnetic pole 14. FIG. 7 shows a configuration in which the cylindrical permanent magnet 15 shown in FIG. 8 is arranged on the outer peripheral surface of the yoke 18, which corresponds to the inner peripheral surface of the feed coil 6, and the same effect as described above can be obtained. Similar effects can be obtained by arranging in various places as described above.

As described above, in the present invention, since the initial excitation can be omitted, the lighting control of the lamp can be omitted. Therefore, it goes without saying that the lamp can be omitted, and the L terminal and the semiconductor element that drives the L terminal can be omitted.

Further, there is an effect that the burden on the battery can be reduced by omitting the initial excitation. Also, since the field current control element arranged inside the voltage regulator is an H-type bridge, the excitation direction of the field current can be switched, so the rectifier diode should be protected even if a strong permanent magnet is arranged. Is possible. Further, since the initial excitation current does not have to be supplied to the field coil, the lamp which is the initial excitation current energization display can be omitted, and thus the lamp drive circuit can be omitted from the voltage regulator. This leads to cost reduction.

[0026]

Since the initial excitation mode of the voltage regulator can be omitted, the circuit required for the initial excitation can be omitted and the configuration of the voltage regulator can be simplified.

[Brief description of drawings]

FIG. 1 is an explanatory diagram illustrating a configuration of a vehicle AC generator according to an embodiment of the present invention.

FIG. 2 is an overall configuration diagram illustrating how the voltage regulator operates.

FIG. 3 is an overall configuration diagram illustrating another mode of operation of the voltage regulator.

FIG. 4 is an operation flowchart of a conventional vehicle AC generator and an operation flowchart of the present invention.

FIG. 5 is an arrangement view of permanent magnets arranged on a rotor.

FIG. 6 is an arrangement view of permanent magnets arranged on a rotor.

FIG. 7 is an arrangement view of permanent magnets arranged on a rotor.

FIG. 8 is a perspective view of a permanent magnet used in FIG.

[Explanation of Codes] 1 ... Shaft, 2 ... Bearing, 3 ... Pulley, 4 ... Slip ring, 5 ... Brush, 6 ... Field coil, 7 ...
Rotor, 8 ... Stator, 9 ... Stator coil, 10 ... Built-in fan, 11 ... Housing, 12 ... Voltage regulator, 13 ... Rectifier diode, 15 ... Permanent magnet, 16 ... B terminal, 17 ...
Earth terminal, 100 ... AC generator for vehicle, 101 ... Battery, 103 ... Rotation speed detection signal, 106 ... Generation voltage detection signal.

 ─────────────────────────────────────────────────── ─── Continuation of front page (72) Inventor Keiichi Masuno 2520 Takaba, Hitachinaka City, Ibaraki Prefecture Hitachi Ltd. Automotive Equipment Division

Claims (2)

[Claims] 1. A field coil, a rotor in which permanent magnets are arranged in a stator coil so that effective magnetic fluxes intersect with each other, a brush for supplying electric power to the field coil via a slip ring, and the fixed member. A stator in which a child coil is arranged, a rectifying diode for rectifying the generated voltage of the stator coil, a voltage regulator for adjusting the generated voltage to a constant value, and a rotor that can hold the stator and rotate the rotor freely. A vehicle alternator comprising a housing held in the housing, the housing comprising only a B terminal for connecting the positive electrode of the battery and a ground terminal for connecting the negative electrode. AC generator for vehicles. 2. The alternator for vehicles according to claim 1, wherein the control element of the field coil incorporated in the voltage regulator is composed of an H-type bridge.