JPS6326254B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a vehicle engine cooling fan shroud assembly for forcing cooling air through a radiator through which engine coolant is circulated. A vehicle engine cooling fan shroud assembly for forcing cooling air through a radiator through which engine coolant circulates includes a support means adjacent to the radiator and a fan shroud assembly adjacent to the radiator attached to the support means. A fan mounting shell is provided, the shell having a peripheral wall portion extending forwardly to provide an inlet for air passing through the radiator, and the shell further extending rearwardly to provide a reduced diameter air outlet. a spoke having a cylindrical portion and extending inwardly from the air outlet; a fan drive motor supported by the spoke and extending axially into the shell; and a fan drive motor coupled to the drive motor and within the shell. A rotatably mounted fan is provided having a central hub mounted on the motor with a plurality of spaced apart arcuate blades extending outwardly from the hub. Such vehicle engine cooling fan shroud assemblies are disclosed, for example, in U.S. Pat.
It is disclosed in No. 4210833.

Prior to the present invention, various engine cooling fan shroud systems have been installed in vehicles to increase fan efficiency and reduce fan-generated noise. Advanced designs utilize a fixed shroud bracket structure to centrally support the fan motor, effectively embedding the shroud fan driven by the motor within the fixed shroud to improve fan operation. is being carried out. To obtain sufficient airflow through the radiator outside the area directly in front of the fan, in some cases the shroud fan is tilted at an angle to the radiator to open the fan to the radiator and direct air toward the fan. It was necessary to improve the lateral flow.

Due to space limitations in crowded engine compartments and higher standards of engine cooling, more air is pumped through a larger area of the radiator,
There is a need for a compact fan shroud package that can more effectively transfer thermal energy from the coolant circulating within the engine.

To this end, a vehicle engine cooling fan shroud assembly according to the present invention has fan blades curved gradually away from the radiator from the central hub to the outer ends of each blade; An annular rotating shroud is fixed to the outer end of the fan blade and is rotatable together with the fan blade within the air outlet, and the rotating shroud allows ambient air flowing into the fixed shell to pass through the fan. axially positioned by curved fan blades at a predetermined spacing sufficient to allow the flow to flow radially into the rotating shroud for circulation.

Thus, in one particular arrangement according to the invention, the outer envelope shroud is fixed relative to the engine cooling radiator and has an integral bracket structure centrally supporting the fan motor.
The fan motor drives a multi-blade fan.
This fan has fan blades that improve efficiency and quietness when pumping air, and this fan blade connects a rotating shroud located within a fixed shroud.
These support special fan blades that provide a very effective air seal in the recirculation flow path between the stationary shroud and the rotating shroud. More particularly, in accordance with the present invention, spaced apart, outwardly extending fan blades are rearwardly curved to effectively support the rotating shroud at a predetermined distance from the radiator. This aft position of the rotating shroud effectively opens the radiator with respect to the fan position, increasing lateral airflow to the fan and
Increased cooling through coolant circulation within the radiator. Additionally, the rearwardly curved fan blade has a curved leading edge that cuts into any air turbulence and reduces the noise generated by the fan blade.

This fan shroud arrangement also allows front mounting of the shroud with respect to the radiator and increases the clearance between the fan components and the vehicle engine to reduce the potential for thermal degradation and facilitate repair. We also offer thinner packaging.

Hereinafter, the present invention will be described in detail with reference to the accompanying drawings.

Referring to Figure 1, brackets 3 and 5 are shown here.
A conventional engine cooling radiator 1 is shown connected to upper and lower elongated horizontal radiator supports 7,9. The radiator 1 is preferably installed on the front side of the vehicle, on the side of the transverse engine 11 shown schematically in FIG. 2. engine 1
1 are connected to a radiator by suitable hoses, between which engine cooling fluid is circulated and thermal energy is dissipated within the radiator.

A cooling fan shroud assembly 15 is located between the radiator and the engine, which directs air through the radiator on demand by a conventional thermostatic controller (not shown). Introducing flow. This assembly includes a fan mounting bracket and fixed shroud unit 17 (preferably molded of a suitable plastic material).
includes. The unit 17 has a box-shaped main shell 18 which has laterally spaced and downwardly projecting mounting legs 19. These legs fit into corresponding holes 21 in the lower horizontal support 9.
The upwardly extending mounting legs 23 are formed with apertures through which threaded fasteners 25 extend and are threadably engaged with the upper radiator support 7 for mounting the unit 17 behind the radiator. ing. The main shell 18 has an open front that covers the face of the radiator. Vertical line 2 separated laterally in Figure 1
9-29 shows the lateral boundaries of area X and the area of application of the fixed shroud. The main shell has an integral rearwardly extending outlet 31 having a bell-shaped inlet and an axially extending cylindrical body terminating rearwardly in an annular lip 32. ing. radially rearwardly from the cylindrical body of the discharge section 31 four arch-shaped spokes 3;
5 extend, and these spokes carry an annular mounting ring 37 at their inner ends. This ring 37 has a central opening for receiving and supporting a generally cylindrical fan drive (motor) 39. The output shaft of this motor drives a fan/rotating shroud unit 41 molded from a suitable plastic material. The unit 41 has a central hub 43 connected to the output shaft of the motor by a threaded fastener 45. A plurality of thin fan blades 47 are curved rearward from the outer periphery of the hub, and the tips of these fan blades are connected to the inner wall of a bell-shaped rotating shroud 49. Because the fan blades are curved, the rotating shroud is located rearward from the rear face of the radiator and at a sufficient predetermined distance d from the radiator, and the first
A sufficient lateral airflow, indicated by arrow A in the figure, is directed into the low pressure area indicated by circle C on the radiator, which is immediately in front of the fan and approximately corresponds to the diameter of the fan. This improves the radiator cooling effect of the shroud fan. This creates a large amount of airflow through the radiator directly in front of the fan, i.e. through C, and also through the radiator core outside the circle C covered by the fixed shroud as indicated by the lateral flow arrow A. This is because a considerable amount of air flow is generated. From this low pressure area, the fan discharges air into the engine compartment.
Recirculation of air from the engine compartment to the fan inlet is prevented due to the shroud shape.

Figure 4 shows the rotating shroud 4 in relation to the front of the hub.
Fan blade 47 when turning back 9
It shows the shape of. If the fan blades had very little rearward curvature, the rotating shroud would be located fairly close to the rear of the radiator, and most of the air passing through the radiator would flow through circle C.
4,210,833), the lateral flow will be significantly reduced as in the known assembly mentioned above (eg, US Pat. No. 4,210,833).

In addition to improving fan cooling with the rotating shroud, this fan blade 47 also provides higher efficiency and quieter pumping. The thin leading edges 53 of the fan blades are arched in the direction of rotation, indicated by arrow R in FIG. become. Therefore, the fan noise is lower than a fan with less or no leading edge curvature. In the inlet area of the fan blade, the twisting of the airfoil cross-section from the hub to the rotating shroud shown in FIG. 4 increases air pumping efficiency with little flow disruption.

[Brief explanation of the drawing]

FIG. 1 is an exploded perspective view of an automobile engine cooling radiator, cooling fan, and fan shroud package embodying a preferred embodiment of the present invention. 2 is a fragmentary side view, partially in section, showing the fan shroud assembly of FIG. 1 connected to a radiator and its support; FIG. FIG. 3 is an end view taken along line 3--3 in FIG. 2 in the direction of arrows, with some components omitted. FIG. 4 is a fragmentary plan view showing a part of the fan, and is a partially cutaway view taken substantially along line 4--4 in FIG. 2 in the direction of arrows. <Explanation of symbols of main parts> 1...Radiator,
DESCRIPTION OF SYMBOLS 11... Engine, 15... Cooling fan shroud assembly, 17... Fan mounting bracket and fixed shroud unit, 18... Shell, 31... Exhaust part, 35... Spoke, 39... Motor, 47... Fan blade, 49... Rotating shroud, 43... central hub, 41... fan, 53... leading edge of blade.

Claims (1)

[Scope of Claims] 1. A vehicle engine cooling fan shroud assembly for forcing cooling air through a radiator through which engine coolant is circulated, the fan and shroud assembly comprising: support means adjacent to the radiator; A fan shroud and fan mounting shell is provided adjacent to the support means, the shell having a forwardly extending peripheral wall to provide an inlet for air passing through the radiator, and the shell further reducing the diameter. a spoke having a generally cylindrical portion extending rearwardly to provide an air exhaust and extending inwardly from the air exhaust; a fan drive motor supported by the spoke and extending axially into the shell; a fan coupled to the drive motor and rotatably mounted within the shell, the fan having a central hub mounted on the motor;
A vehicle engine cooling fan shroud assembly having a plurality of spaced apart arcuate blades extending outwardly from the central hub, the fan blades extending away from the radiator from the central hub to an outer end of each fan blade. An annular rotating shroud is fixed to the outer end of the fan blade so that it can rotate together with the fan blade within the air outlet, and the rotating shroud axially positioned by the curved fan blades at a predetermined spacing sufficient to allow ambient air entering the shell to flow radially into the rotating shroud for circulation by the fan; A vehicle engine cooling fan shroud assembly characterized by: 2. A vehicle engine cooling fan/shroud assembly according to claim 1, wherein the leading edge of the fan blade is curved in a direction opposite to the rotational direction. Three-dimensional.