JPH05219685A - Vehicle AC generator cooling system - Google Patents

Abstract

(57) [Abstract] [Objective] To extend the semiconductor life of a rectifier and a voltage controller by efficiently cooling a vehicle AC generator at low speed rotation without burdening the battery. [Composition] A cover with a duct is provided behind the vehicle AC generator at the rear side of the vehicle AC generator, and the tip of the duct is installed in front of the vehicle to guide the outside air as cooling air. However, when the vehicle is idle or in a traffic jam, the cooling air from the outside air cannot be guided. Therefore, the cooling air is forcibly taken in by operating the electric fan installed inside the duct provided on the rear side.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a vehicle AC generator cooling system.

[0002]

2. Description of the Related Art A conventional vehicular AC generator is disclosed in JP-A-56-98.
As described in No. 358, cooling fans were fixed to both sides of the rotor, and the rotation of the rotor caused the cooling fan to rotate and generate cooling air.

[0003]

In the above-mentioned prior art, the amount of cooling air generated depends on the number of rotations of the rotor, and reaches its limit at low speeds (idle rotations). Also, in recent years, the temperature inside the engine compartment of automobiles has been increasing year by year as the engine room becomes more dense, and the cooling efficiency is increased by the conventional method that takes in high temperature air around the vehicle alternator as cooling air. There was a problem that was bad.

Further, as the electric load of automobiles has increased in recent years, the capacity of the vehicle AC generator has increased, and the heat generation of the vehicle AC generator itself has also increased due to the need for smaller size and lighter weight. There was a problem that it was not possible to meet the demand for smaller size and higher output.

An object of the present invention is to effectively take in air having a low temperature close to the outside air as cooling air at the time of low-speed rotation where the cooling air is at the limit, and to efficiently use a vehicle AC generator. By cooling.

[0006]

In order to achieve the above object, a cover with a duct is provided on the rear side of an alternator for a vehicle, the tip of the duct is installed in front of the vehicle, and the outside air is used as cooling air. Lead.

However, since the cooling air from the outside air cannot be guided when the vehicle is idle or in a traffic jam, the cooling air is forcibly taken in by operating the electric fan installed inside the duct provided on the rear side. ..

[0008]

Since the tip of the rear duct is installed in front of the vehicle, cooling air can be guided from the outside air to the vehicle AC generator while the vehicle is running, so that cooling can be performed efficiently. Further, even when the cooling air cannot be guided from the outside air at the time of idling, traffic jam, etc., the cooling air can be forcibly taken in by driving the electric fan provided inside the duct. In addition, the electric fan can be monitored by a temperature sensor provided in the voltage control device, and can be turned on when a temperature provided by a relay provided in the electric fan exceeds a certain temperature, and turned off when the temperature drops. Cooling can be performed effectively without burdening the user. In addition, as described in claim 2, since charging and discharging may be in a discharging state at the time of idling or during traffic jam, in order to prevent the battery from going up, priority is given to the lowering of the battery voltage and even if the temperature is high, the electric fan You can prevent the battery from going up without driving.

[0009]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to FIGS.

FIG. 1 shows an AC generator for a vehicle.

The rotor 1 is fixed to the rotor shaft 2,
A front cooling fan 3 and a rear cooling fan 4 are fixed to both end surfaces of the rotor. The rotor shaft 2 is supported by bearings 7 and 8 held by a front housing 5 and a rear housing 6.

The stator 9 is held between the front housing 5 and the rear housing 6. Further, a rectifying device 10 and a voltage control device 11 are fixed to an inner inner wall or an outer outer wall of the rear housing 6, and a ducted cover 12 is fixed to the outer side of the rear housing 6. An electric fan 14 having a cooling fan 13 is attached inside the duct. On the rotor shaft 2,
A drive pulley 16 is fixed by a pulley nut 15, and the drive pulley 16 is driven by a belt by an internal combustion engine (not shown). Internal combustion engine drive pulley 16
When the rotor 1 is driven to rotate, the front side cooling fan 3 and the rear side cooling fan 4 fixed to the rotor 1 simultaneously rotate, and a flow of cooling air is generated as indicated by an arrow in the figure. For the rear side, the rear side intake 1
The cooling air sucked from 7A and 17B is rectified by the rectifying device 10,
After cooling the voltage regulator 11, the stator winding 18 is cooled and discharged from the rear discharge ports 19A and 19B. However, since the front side cooling fan 3 and the rear side cooling fan 4 rotate at the same time as the rotor 1, the air volume of the cooling air depends on the rotational speed of the rotor 1, and a sufficient air volume is obtained at low speed when the rotational speed is low. Cannot be secured. Even when the duct is installed, cooling air can be obtained when the vehicle is running, but cooling air cannot be obtained from the duct when the vehicle is stopped, such as when the vehicle is idle or when traffic is congested. In this case, since the cooling air can be forcibly guided from the outside air by driving the electric fan installed inside the duct, the cooling can be effectively performed when the vehicle is stopped.

However, when the electric fan is used when the vehicle is stopped during idling, traffic jams, etc., the battery is often charged and discharged, so that the battery may go up.

Therefore, the relay installed in the electric fan is turned on and off by the temperature sensor provided in the voltage controller.
By performing FF, it is possible to avoid extra load on the battery. Further, the battery control can be prevented by setting the priority of the battery voltage and the power Tr temperature of the control device in the order of the battery voltage and the power Tr temperature in the voltage control device.

[0015]

According to the present invention, the outside air can be forcibly taken in as cooling air at the time of low speed rotation in which the rectification of the vehicle AC generator and the heat generation of the voltage control device itself are the largest, and the temperature sensor is used. By monitoring the temperature of the voltage-controlled power Tr, cooling can be reliably performed without burdening the battery, so that the vehicle AC generator can be effectively cooled.

[Brief description of drawings]

FIG. 1 is a vertical sectional view of an automotive alternator according to an embodiment of the present invention.

FIG. 2 is a conceptual diagram of the same.

FIG. 3 is a system diagram of the same.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Rotor, 4 ... Rear side cooling fan, 6 ... Rear side housing, 12 ... Cover with a duct, 14 ... Electric motor, 15 ... Cooling fan, 20 ... Ventilation tube.

Front page continuation (72) Inventor Michiharu Chiba 2520 Takaba, Katsuta City, Ibaraki Prefecture Hitachi, Ltd. Automotive Equipment Division

Claims (2)

[Claims] 1. A vehicle including a rotor driven by an engine of a vehicle, front and rear housings for supporting the rotor, a stator sandwiched between the housings, a rectifying device fixed to the housing, and a voltage control device. In the alternator for automobiles, one side for sending cooling air to the outside of the rear housing is provided with an inlet at the front so that cooling air is sucked from outside the vehicle, and a cover with a cylindrical duct is provided, and forced cooling air is provided inside this duct. A cooling system for a vehicle alternator, characterized in that an electric fan for feeding the electric power is provided, and the electric fan is turned on and off by a temperature sensor installed in the voltage control device. 2. A control device for monitoring the power Tr temperature with a battery voltage and a temperature sensor, and stopping the electric fan even when the battery voltage is below a certain voltage even if the sensor temperature is above a certain temperature. And claim 1
The cooling system for the vehicle alternator described.