JPS6367004B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a rotation speed control device for a cooling fan for a vehicle, which allows a cooling fan device to properly cool a radiator or a condenser of a vehicle.

Conventionally, electric fans have been used to cool automobile radiators and cooling condensers in air conditioners. Figure 1 shows the radiator cooling fan and its drive control circuit, where 1 is the power supply, 2 is the ignition switch, 3 is the motor fan, 4 is the water temperature switch, 5 is the radiator, and 6 is the cooling water inlet hose. , 7 are cooling water outlet hoses.

FIG. 2 is an enlarged sectional view of the water temperature switch 4, showing a bellows 42 having a contact 42a inside the casing 41.
The inside thereof is filled with an expansion material (for example, wax) 43 that expands due to a rise in temperature, and two terminals 45 and 46 protrude from the outside through an insulating material 44. 47 is the temperature sensing part of the water temperature switch 4 (September 1970, service bulletin published by Nissan Motor Co., Ltd., introduction of Cheery F- and F10 series cars,
(see paragraph 62).

In this cooling fan rotation speed control circuit, when the water temperature exceeds a certain temperature, the expansion material 43 expands and the contact 42a of the bellows 42 and the terminal 45 come into contact with each other.
A power supply circuit to the fan motor is formed to rotate the cooling fan. This operating set point is a predetermined constant water temperature of approximately 80°C. Therefore, regardless of whether it is summer or winter, or regardless of the vehicle speed, the cooling fan will rotate at full speed if the water temperature reaches a constant value. However, in winter, when the outside temperature is low, the radiator may be sufficiently cooled by the wind while driving for a short distance even if the cooling fan is not turned, and even if it is rotated, it may be sufficient if it is rotated at a low speed. There were cases where the cooling fan was cooling the unit more than necessary.

The present invention has been made in view of the above points, and in order to perform appropriate cooling, when the temperature of the cooling medium exceeds a predetermined value, the cooling fan is rotated according to the temperature of the cooling medium, Even if the temperature exceeds a predetermined value, if the outside temperature is below a predetermined value or the vehicle speed or engine speed is above a predetermined value, the fan motor's rotation speed is reduced to a rotation speed corresponding to the coolant temperature. It is designed so that it rotates.

The present invention will be explained below based on the drawings.

FIG. 3 shows an embodiment of the water temperature switch used in the rotation speed control device according to the present invention, and FIG.
The figure shows the electrical circuit of a rotation speed control device constructed using the same water temperature switch.

The water temperature switch shown in FIG. 3 is a three-stage operating switch, in which the same reference numerals as in FIG. 1 indicate the same components. This embodiment differs from the embodiment shown in FIG. 1 in that the shape of the contact 42a of the bellows 42 is a stepped shape having an apex A and stepped portions B and C, and a terminal 46 is used as a terminal projecting to the outside. 3 more
This is because book terminals 48, 49, and 50 are provided.

On the other hand, in the circuit of the rotation speed control device shown in Fig. 4, 8 is a cooling correction that corrects the cooling effect of the fan according to conditions that affect the cooling effect of the engine, such as the outside temperature and the running condition of the vehicle. Specifically, the switches include an outside temperature switch that is turned on when the outside temperature is below a predetermined outside temperature, and an engine speed switch or a vehicle speed switch that is turned on when the engine speed or vehicle speed is above a predetermined value. 9 is 3
10 is a cooling fan rotation switching relay, and 11 is a resistor.

Next, the operation of the above-mentioned control device configured using an outside temperature switch as the cooling correction switch 8 will be explained.

When the outside temperature is high, the outside temperature switch 8 is in the OFF state, so the relays 9 and 10 are not energized, and their contacts are in the state shown in FIG. When the temperature of the engine cooling water rises and the bellows 42 expands and the step C of the contact 42a contacts the terminal 48, the resistor 11 is connected in series to the power supply circuit of the motor 3 of the cooling fan. 3 rotates at slow speed. In this way, if the water temperature falls due to the cooling action of the cooling fan, the bellows 42 will contract, and the step C of the contact 42a will separate from the terminal 48, stopping power supply to the motor.However, conversely, due to insufficient cooling, the water temperature will further increase. When the bellows 42 rises, it further extends, and the stepped portion B of the contact 42a comes into contact with the terminal 49, so that the motor 3 is directly applied with power supply voltage and rotates at full speed.

When the outside temperature is low (for example, below 10 to 20°C)
Since outside temperature switch 8 is turned on, relays 9 and 10 are turned on.
is energized and its contact moves to the position indicated by the dashed line. Therefore, the water temperature rises and the bellows 42 expands and its contact point 4
Even if the stepped portion C of the motor 2a contacts the terminal 48, a power supply circuit to the motor 3 is not formed, so the motor 3 does not rotate. As the water temperature further increases, the bellows 42 expands and its contact point 4
When step B of 2a comes into contact with terminal 49, motor 3 is supplied with power via resistor 11 and rotates at a low speed.
When the water temperature further increases and the bellows 42 expands and the apex A of the contact 42a contacts the terminal 50, the power supply voltage is directly applied to the motor 3, causing the motor to rotate at high speed.

Note that the contact 42a of the bellows 42 and each terminal 4
The contact temperature with terminals 8, 49, and 50 is, for example, terminal 4.
8 is around 80°C, terminal 49 is around 90°C, terminal 50 is around 90°C.
The temperature is around 100°C.

In the above embodiment, the outside temperature switch was used as the cooling correction switch, but the engine speed switch,
The operation is the same even if a vehicle speed switch is used. In the case of a cooling condenser, the contacts of the bellows may be opened and closed in response to changes in the temperature or pressure of the refrigerant (eg, fluorocarbon gas) circulating in the cycle.

As explained above, the present invention provides a cooling fan device that rotates a cooling fan motor when the temperature of the cooling medium is above a predetermined temperature, when the outside temperature is below a predetermined value or when the vehicle speed or engine rotational speed is above a predetermined value. The fan motor rotation speed is corrected to reduce when The cooling effect of the fan can be weakened, and therefore the power consumption of the fan motor and the engine load can be reduced, so that fuel efficiency can be improved. In particular, if the rotational speed of the cooling fan is controlled based on the engine rotational speed or vehicle speed, the cooling fan rotates at a low speed, eliminating concerns about noise.

[Brief explanation of drawings]

Fig. 1 is a conventional cooling fan device and its drive control circuit, Fig. 2 is a sectional view of an example of a water temperature switch used in the cooling fan device shown in Fig. 1, and Fig. 3 is a cooling fan rotation speed control according to the present invention. FIG. 4 is a sectional view of an embodiment of a water temperature switch used in the apparatus, and is a rotational speed control apparatus according to the present invention constructed using the water temperature switch shown in FIG. 3. 1... Power supply, 2... Ignition switch, 3... Fan motor, 4... Water temperature switch, 42... Bellows, 42a... Contact, 5... Radiator, 6... Inlet hose, 7... Outlet hose, 8... Cooling compensation switch, 9...3-stage operating point switching relay, 1
0...Cooling fan.

Claims (1)

[Claims] 1 Cooling fan driving means that drives a cooling fan motor at a rotation speed corresponding to the temperature while the temperature of the cooling medium exceeds a predetermined value; A rotation speed correction means is provided for correcting the rotation speed of the fan motor so as to reduce the rotation speed to a rotation speed corresponding to the temperature of the cooling medium when the vehicle speed or engine rotation speed is below a predetermined value or above a predetermined value. A rotation speed control device for vehicle cooling fans.