JPS6124657Y2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION This invention relates to a control device that controls the rotation, stop, and rotational speed of a fan motor for ventilating a radiator for heat radiation of engine cooling water.

In order to efficiently dissipate heat from cooling water, a fan is used to ventilate the core of the radiator. Means for rotating this fan include those that are rotated directly by the output shaft of the engine or via a belt, and those that are rotated by a motor. However, in the case of a fan that is rotated by an engine, the fan rotates immediately after the engine is started, which not only takes a long time to warm up the engine, but also increases horsepower loss when the engine rotates at high speed.
In addition, in the past, when a fan was rotated by a motor, only the rotation and stopping of the motor was controlled intermittently using a thermoswitch that detected the air temperature in the shroud behind the radiator.
(No. 86006), the water temperature inside the radiator fluctuates widely, and the thermoswitch has to be turned on and off frequently, resulting in large power losses and more frequent switch failures. Also,
A device that detects the cooling water temperature and drives the motor via a transistor so that the yawter speed can be changed continuously (Japanese Patent Application Laid-open No. 77235/1983,
However, transistors have low mechanical strength and are therefore unreliable, making it difficult to pass large currents through them.

This invention eliminates the above-mentioned drawbacks by controlling the motor for rotating the fan to rotate, stop, and also control the speed of rotation via a transformer that has high mechanical strength and can flow a large current. It is an object of the present invention to provide a control device for a fan motor for radiator ventilation.

Hereinafter, the present invention will be explained with reference to drawings showing embodiments.

FIG. 1 shows the overall configuration of a control device for a radiator ventilation fan motor according to the present invention. Inside the opening 2a of the shroud 2, which is fixed so as to surround the rear part of the core part 1 of the radiator, the shroud 2
A fan 5 rotated by a motor 4 fixed via a bracket 3 is attached to the fan 5 . A temperature sensor 8 is attached to a part of the shroud 2 to detect the temperature of the air in a space 6 surrounded by the shroud 2 and the core part 1 and send a signal to a control circuit 7. 9 is a battery as a power source, and the motor 4
is connected to the battery 9 via a control circuit 7. A thermoswitch 11 is attached to the lower tank 10 of the radiator to detect the water temperature in the radiator and to connect or disconnect the radiator. The control circuit 7 passes current to the motor 4 only when the water temperature in the radiator exceeds a certain value and the thermoswitch 11, which was open when the temperature was low, is closed.

FIG. 2 shows one example of the control circuit 7, and the operation of the fan motor control device of the present invention will be explained below with reference to FIG. In the rotating circuit illustrated in FIG. 2, an element whose resistance decreases as the temperature rises, such as a thermistor, is used as the temperature sensor 8.

First, while the engine is still cold after starting, the thermoswitch 11 is open, so the motor 4 does not rotate. Therefore, the core portion 1 is not ventilated, and the warm-up operation can be completed in a short time.

When the temperature of the cooling water in the radiator rises to a certain temperature at which cooling should start as the engine temperature rises, the thermoswitch 11 closes and the current from the battery 9 passes through the secondary coil 12a of the controller 12. The current flows to the motor 4, and the motor 4 rotates. The water temperature inside the radiator is relatively low, and the space inside the shroud 6
When the air temperature is also low, the resistance of the temperature sensor 8 connected to the primary coil 12b of the controller 12 via the transistor 13 is large, and the
Since the voltage applied to 2b is suppressed to a low level, the motor 4 is driven at low speed almost solely by the current passing through the secondary coil 12a.

When the temperature of the cooling water in the radiator rises further as the engine temperature rises, the air quality in the space 6 increases and the resistance value of the temperature sensor 8 decreases.
The voltage applied to the primary coil 12b of the transformer increases, and the magnetic field generated in the primary coil 12b amplifies the magnetic field of the secondary coil 12a, increasing the voltage of the coil 12a, which causes the voltage to be sent to the motor 4. The current flowing through the motor 4 increases, and the motor 4 rotates at high speed. That is, when the temperature of the cooling water in the radiator is above a certain value and the thermoswitch 11 is closed, the temperature of the space 6 between the core part 1 and the shroud 2 (this temperature increases with the temperature of the cooling water). up and down)
The rotational speed of the motor 4 changes continuously in accordance with this. Since the resistance change of the temperature sensor 8 is continuous, the current flowing through the motor 4 also changes continuously, and the rotational speed of the motor 4 also changes continuously, making it possible to always obtain the optimum motor rotational speed. Temperature fluctuations can be suppressed to a small extent. Therefore, the number of times the thermo switch 11 is turned on and off can be significantly reduced, which is highly effective in reducing switch failures.

Note that if the temperature sensor 8 detects the air temperature in the space 6 inside the shroud instead of detecting the cooling water temperature, the temperature in this space 6 will change rapidly due to increases and decreases in vehicle speed and atmospheric temperature. If the motor speed is controlled based on this, the motor speed will be controlled in anticipation of increases and decreases in the coolant temperature, and fluctuations in the coolant temperature can be significantly reduced.

[Brief explanation of the drawing]

FIG. 1 is a side view showing the overall configuration of a control device for a fan motor according to the present invention, and FIG. 2 is a circuit diagram showing an example of the control device. 1: Core part, 2: Shroud, 4: Motor,
5: Fan, 6: Space, 7: Control circuit, 8: Temperature sensor, 9: Battery, 11: Thermoswitch.

Claims (1)

[Scope of utility model registration request] A motor 4 for rotating the fan and a battery 9 serving as a power source are connected via a control circuit 7, and the control circuit 7 includes:
A thermoswitch 11 detects the water temperature in the radiator and connects the motor 4 to the battery 9 through the secondary coil 12a of the controller 12 to rotate the motor 4 when the water temperature exceeds a certain value, and the core part 1 and the shroud 2 of the radiator. The primary coil 12b of the controller 12 is detected via the transistor 13.
A battery current is applied to the secondary coil 12a, and the current passing through the secondary coil 12a is adjusted to adjust the motor 4 as the air temperature changes.
A control device for a radiator ventilation fan motor, characterized in that a temperature sensor 8 for changing the rotation speed of the fan motor is attached.