JPH0545837Y2 - - Google Patents

Description

[Detailed Description of the Invention] [Industrial Field of Application] The present invention is particularly applicable to radiator fans for automobiles, where the ventilation resistance of the radiator is large.

[Prior art]

Since various devices are housed in the engine room of an automobile, the ventilation of the radiator is poor. Furthermore, radiators are often installed such that one for engine cooling, one for intercooler, and one for indoor air conditioning are stacked on top of each other. As a result, the overall ventilation resistance tends to become worse. Therefore, conventional axial fans may not be able to sufficiently cool the radiator.

[Means to solve the problem]

As a result of various experiments, the present inventor devised a fan that solves the above problems. Its composition is as follows.

That is, the pressure coefficient Ψ=0.25 to 0.35, the boss part 1 has a truncated cone shape, a plurality of wing parts 2 are arranged at equal intervals on the outer periphery of the boss part 1, and the radial tip edge of the wing part is In a fan formed parallel to the axis of the boss part 1, the angle θ between the outer peripheral surface of the boss part 1 and the axis is θ=27.5° to 35.5°, and the radius of the tip at the trailing edge of the wing part 2 is The relationship between R _p and the radius R ₂ of its root is set as R ₂ /R _b =0.45 to 0.55, and the imaginary line l perpendicular to the outer surface of the boss 1 at the root of the trailing edge of the wing 2 , the intersection of the imaginary line l and the tip edge of the wing section 2
The distance D to the trailing edge of the wing is D/T with respect to the wingspan T
= 0.65 to 1.0, and the cylindrical portion 3 of the shroud is fitted by an axial length S so that the rear end portion of the tip edge of the wing portion 2 is exposed close to the tip edge. This is a radiator fan characterized in that the fitting ratio thereof is S/T=0.5 to 0.7.

〔Example〕

Next, embodiments of the present invention will be described based on the drawings.

FIG. 1 is a schematic axial cross-sectional view showing the state in which the present radiator fan is used, FIG. 2 shows its main parts, and FIG. 3 is a front view of the same fan.

In this radiator fan, a boss portion 1 is formed in a truncated conical shape, and blade portions 2 are arranged at equal intervals on the outer peripheral surface of the boss portion 1. The central part of the boss part 1 has a large opening, and an annular mounting surface 7 is formed on the inner peripheral edge of the central part.
is integrally fixed to the boss portion 1. This fan is made of a synthetic resin molded body, and the wings 2 are spaced slightly apart from each other to facilitate molding. In addition, the base of the wing section 2 is attached at a predetermined angle with respect to the axis of the boss section 1, and the wing section 2 itself has a slightly twisted shape as it goes from the base to its tip edge. There is. These torsional angles are small compared to those of conventional axial fans. The front edge 12 of the wing section 2 is raised slightly from the rear of the front end of the boss section 1, as shown in FIGS. 1 and 2, so that the airflow that has passed through the radiator 4 is smoothly guided rearward. It's starting to get worse. Next, the leading edge 11 of the wing portion 2 is formed parallel to the axis, and the trailing edge 13
coincides with the rear end of the boss portion 1. In addition, boss part 1
The inclination angle θ with respect to the axis is preferably 27.5° to 35.5°. If it is smaller than 27.5°, it is not possible to generate a large negative pressure on the back side of the radiator 4. Furthermore, it has been confirmed through experiments that if the angle is 36 degrees or more, the resistance of the fan becomes too large, resulting in poor efficiency with respect to the power, and as a result, the amount of air passing through the radiator 4 becomes small. next,
The ratio of the tip radius R _p at the trailing edge 13 of the wing section 2 to the radius R _b at the center root of its front and rear edges is 0.45
~0.55 is preferable. If this value exceeds 0.55, the cross-sectional area of the air outlet on the exit side of the fan becomes too small, which impairs ventilation and results in a decrease in the amount of air passing through the radiator 4. Moreover, if it is less than 0.45, the boss portion will become too small, making it difficult to attach the required fan clutch. At the same time, the negative pressure on the back side of the radiator 4 cannot be made sufficiently large.

Next, D/T representing the depth ratio of the wing section 2, that is, when an imaginary line l perpendicular to the outer surface of the boss section 1 at the root of the trailing edge of the wing section 2 is projected onto the wing section 2, the imaginary line l and The ratio D/T of the distance D between the intersection with the leading edge of the wing section 2 (Fig. 2) and the trailing edge of the wing section 2 to the wing span T is
0.65-1.0 is most preferred. This means that its value is 1.0
This is because the width of the wing portion 2 is too narrow and sufficient negative pressure on the back side of the wing portion 2 cannot be obtained. Along with that,
If the value is less than 0.65, the blade span of the wing section 2 will be too large, resulting in extremely low efficiency, and the thickness of the fan as a whole will become large, impeding its miniaturization.

Next, the cylindrical portion 3 is fitted opposite the tip edge 11 of the wing portion 2 . The cylindrical portion 3 is connected to a shroud body 14 via an annular rubber plate 6, and the open end of the shroud body 14 is fixed to the tank 5. Further, the cylindrical portion 3 is fixed to the engine 9 via a stay 10. Incidentally, the flange portion of the clutch 8 is fixed to the mounting surface 7 of the boss portion 1. The drive side shaft of the clutch 8 is connected to the engine 9.
It is connected to the crankshaft of the motor through gears, etc.

In this embodiment, the cylindrical part 3 of the shroud is connected to the wing part 2.
It was formed so that only the middle part and the front end of the holder were fitted, and the rear end was exposed. This is to ensure a sufficient exit area of the fan and increase the amount of ventilation, and the S/T was set to 0.7 or less. In addition, S/T is 0.5
It was set in the range of ~0.7. Here, the value was set to 0.5 or less because if the cylindrical part 3 is too short, backflow will occur at the blade tip, resulting in a decrease in ventilation volume and a large negative pressure on the back side of the radiator 4. Because you can't. Next, this fan is a high static pressure fan that operates with a pressure coefficient Ψ in the range of 0.25 to 0.35. This high static pressure fan is designed to have the specifications of each of the fans described above, thereby increasing the air volume and improving the heat exchange performance. FIG. 4 shows the relationship between the pressure coefficient Ψ and the flow rate coefficient Φ. Here, the curves A, B, and C represent respective embodiments of the fan of the present invention, and the angle θ with respect to the axis of the boss portion thereof is
is 30°, R _b /R _p are 0.50, 0.47, and 0.51, respectively, D/T is 0.87, 0.76, and 1.07, and S/T is 0.5, 0.5, and 0.5, respectively. radius
R _p is 335mm, 240mm, 212.5mm. Further, the numbers of the respective wing portions 2 are 10, 10, and 12, respectively. Fourth
In the figure, curves A, B, and C are the pressure coefficient curves of the respective fans with Φ as the horizontal axis, and A', B', and C' are the pressure coefficient curves of the radiators applied to the respective fans. Therefore, the intersection of the respective curves becomes the operating point of each embodiment. Curve D shows the pressure coefficient characteristics of a conventional axial flow fan. Next, in FIG. 4, the curves of the respective fans with Φ on the horizontal axis and η (efficiency) on the vertical axis are A ₁ , B ₁ , and C ₁ . Each of the above-mentioned operating points is located near the maximum value of the efficiency curve. From this, it can be seen that each of the Examples is a fan with good efficiency, high static pressure, and large air volume. In Fig. 4, the experiment was conducted with the angle θ of the boss portion fixed at 30°, but almost the same results were obtained with other numerical angles. Moreover, the same applies to other specifications within the scope of the present invention. Note that the pressure coefficient Ψ and the flow rate coefficient Φ are expressed by the following equations.

Flow coefficient Φ=Q/A・u Pressure coefficient Ψ=P _s /γ/2g Power coefficient λ=L/γ/2g Efficiency η=Φ・Ψ/λ Q: Flow rate m ³ /s A: Flow path area πR _p ² (1-v ² ) v: Boss ratio R _b /R _p u: Peripheral speed 2πR _p N N: Rotation speed γP _s P _s : Static pressure mmAg (Kg/m ² ) γ: Specific gravity Kg/m ³ [ Effects of the Invention] The radiator fan of the present invention can provide a high static pressure cooling fan with a large air volume and high efficiency when the radiator has a large ventilation resistance. That is, the value of θ and R _b /R _p , D/T, S/T
Since the values of are set within specific ranges, it is possible to provide a large amount of air passing through the radiator and a high fan efficiency.

[Brief explanation of the drawing]

Fig. 1 is a schematic axial cross-sectional view showing how the present radiator fan is used, Fig. 2 shows its main parts, Fig. 3 is a front view of the same fan, and Fig. 4 shows respective implementations of the fan of the present invention. The relationship between flow coefficient, pressure coefficient and efficiency in an example is shown. 1...Boss part, 2...Wing part, l...Virtual line, 3
... Cylindrical part, 4 ... Radiator, 5 ... Tank,
6... Annular rubber plate, 7... Mounting surface, 8... Clutch, 9... Engine, 10... Stay, 11...
...Tip edge, 12... Front end edge, 13... Rear end edge, 1
4... Shroud body.

Claims (1)

[Claims for Utility Model Registration] Pressure coefficient Ψ = 0.25 to 0.35, the boss portion 1 has a truncated conical shape, and a plurality of wing portions 2 are provided on the outer periphery of the boss portion 1.
are arranged at equal intervals, and the radial tip edge of the wing section is formed parallel to the axis of the boss section 1, and the angle θ between the outer circumferential surface of the boss section 1 and the axis line is θ=27.5. ° to 35.5°, and the relationship between the radius R _p of the tip at the trailing edge of the wing section 2 and the radius R _b of the center root of the front and rear edges is R _b /R _p = 0.45 to 0.55, and the wing section 2 When an imaginary line l perpendicular to the outer surface of the boss portion 1 at the root of the trailing edge is projected onto the wing portion 2, the intersection of the imaginary line l and the tip edge of the wing portion 2 and the wing portion 2 The distance D from the trailing edge of the blade has a relationship of D/T=0.65 to 1.0 with respect to the wing width T, and the rear end of the leading edge is exposed close to the leading edge of the wing section 2. The cylindrical part 3 of the shroud is fitted by the axial length S, and the fitting ratio is S/T=
Radiator fan characterized by 0.5~0.7. However, the pressure coefficient Ψ indicates the operating point of the fan, and indicates the intersection of the pressure coefficient curves of the fan and the radiator with the flow coefficient Φ as the horizontal axis.