JPS5821087B2 - Cooling fan fluid joint control device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a fluid coupling control device used in a cooling fan, particularly an engine cooling fan of an automobile.

Fluid coupling devices, which are generally used in automobile engine cooling fans, generate an output rotation speed that is higher than necessary when the automobile suddenly accelerates, resulting in disadvantages such as power loss and increased noise. Therefore, various control methods have been considered. I've been exposed to it.

For example, in the fluid couplings disclosed in Japanese Patent Application Laid-open No. 50-149867 or Japanese Patent Application Publication No. 51-12060, the case of the fluid coupling or the partition plate integrally attached thereto is provided with a Some models are equipped with an inertial on-off valve that closes the outlet in response, but in this method, the inertial on-off valve is installed in the case or on the partition plate, so the above-mentioned on-off valve closes the outlet during sudden acceleration. When the fan is closed, fluid is prevented from entering the torque transmission chamber and the fan rotation speed decreases, but once the fan rotation speed decreases,
Since the on-off valve returns to the open side again, the introduction of fluid into the torque transmission chamber is resumed, and the rotational speed of the fan increases again.

In this way, the phenomenon in which the rotational speed of the fan repeatedly decreases and increases due to the inertial operation of the inertial on-off valve provided on the partition plate of the case is called the bunching phenomenon.

As shown by the two-dot chain line FNo in Figure 3, this kind of bunching phenomenon is repeated several times to reach a steady rotation speed, but in this case, the fan rotation speed cannot be lowered to the desired low value. Not only is this impossible, but it is also unavoidable that fluctuations in drive torque, output loss, and increase in noise due to the bunching phenomenon described above are inevitable.

The present invention provides a fluid coupling control device for a cooling fan that overcomes the bunching phenomenon during rapid acceleration as described above, has good responsiveness, and has low power loss and noise.

An example of this will be described below with reference to the drawings.

Reference numeral 1 denotes a drive shaft driven by an automobile engine, and a rotor 2 is integrally attached to the tip of the drive shaft with bolts 3 or the like.

- the rotor 2 has a fluid reservoir 2a inside it;
At the same time, a fluid outlet 2b communicating with the storage chamber 2a is provided near the outer periphery.

Reference numeral 4 denotes an inertia-operated valve disposed in the storage chamber 2a, which closes the outlet 2b only when the rotor 2 suddenly accelerates. Swinging elastic swinging member 4b1 bolt nut 3a,
It consists of a base 4C attached to the storage chamber 2a side of the rotor 2 by 3b.

5.5a is an inertia operated valve 4 provided on the rotor 2
A pair of protrusions that regulate the swing range of the case.
The rotor 2 is rotatably disposed in an interior sealed with a high viscosity fluid such as silicone oil to form a torque transmission chamber 6a, and is connected to the drive shaft 1 via a bearing 7 on the negative side. It is rotatably supported.

Furthermore, the case 6 includes a torque transmission chamber 6a and its fluid storage chamber 6.
A partition plate 8 is provided integrally with the case 6 to separate the
The partition plate 8 is provided with an inlet 8a through which fluid flows from the fluid storage chamber 6b to the torque transmission chamber 6a.

Reference numeral 9 designates a temperature-sensitive valve for controlling the amount of fluid passing through the inlet port 8a, with a valve body 9a disposed at one end, the other end pivotally supported by the partition plate 8, and a valve body 9a between them. A spring 10 is provided that always biases the valve body 9a in the opening direction, and the valve body 9a is configured to open and close in response to the operation of the temperature sensing section S.

11 is a cooling fan, stand, nuts 3c, 3d
They are attached to the outside of the case 6 at appropriate intervals.

Note that the case 6 has a fluid storage chamber 6b rather than a torque transmission chamber 6a.
A flow path 6c is provided for circulating fluid to.

The operation of the fluid coupling control device configured as described above is as follows.

That is, when the automobile accelerates rapidly, the rotation of the rotor 2 via the drive shaft 1 is also rapidly increased as the rotation of the engine rapidly increases.

Therefore, inertia acts on the valve body 4a of the inertia-operated valve 4,
When the inertia force obtained by multiplying the mass of the valve by the angular acceleration of the rotor 2 overcomes the restoring force of the elastic swinging member 4b, the inertia-operated valve 4 moves in the opposite direction to the rotational direction A of the rotor 2.

That is, it swings in the direction of arrow B in FIG. 2 and closes the outlet 2b as shown by the solid line in the same figure.

Therefore, the torque transmission chamber 6a is transferred from the storage chamber 2a of the rotor 2.
The viscous fluid is prevented from flowing out to the torque transmission chamber 6a.
Since the viscous fluid inside is returned to the fluid storage chamber 6b through the flow path 6c, the amount of viscous fluid inside the torque transmission chamber 6a is insufficient, and the torque to be transmitted from the rotor 2 to the case 6 is reduced. , the rotational speeds of the case 6 and the cooling fan 11 decrease instantaneously.

As shown by the solid line NF in Figure 8, the fan rotation speed decreases at a steep slope at the same time as sudden acceleration.
Since the inertia operated valve 4 is attached to the rotor 2,
Since the valve 4 follows the accelerating operation of the rotor 2, the hunting phenomenon as in the conventional example does not occur, so the fan rotation speed is maintained at a low rotation speed of 5, and as the accelerating operation of the rotor 2 ends, The rotation speed will return to normal speed again.

As described above, in the present invention, the inertia-operated valve 4 is provided on the rotor 2, so that an excessive increase in the output rotation of the cooling fan during sudden acceleration is prevented, and as shown by the two-dot chain line NFo in FIG. The conventional hunting phenomenon is also suppressed, fluctuations in engine drive torque are also prevented, and there are effects such as output savings and noise reduction.

[Brief explanation of the drawing]

Fig. 1 is a longitudinal sectional view of the fluid joint control device of the present invention, Fig. 2 is an enlarged explanatory diagram of the main parts of the device, and Fig. 3 shows the operating status of a cooling fan equipped with the device during sudden acceleration. FIG. 1: Drive shaft, 2: Rotor, 2a: Storage chamber, 2b 2 outlets, 4: Inertial operation valve, 4a: Valve body, 4b 2 elastic rocking members, 4c: Base, 5.5a: Protrusion, 6: Case, 6
a: torque transmission chamber, 6b=fluid storage chamber, 6c: flow path,
7: Bearing, 8: Partition plate, 8a: Inlet, 9: Temperature-sensitive operation valve, S: Temperature-sensing section, 10: Spring, 11: Cooling fan.

Claims (1)

[Claims] 1 In a fluid coupling in which a torque transmission chamber is formed by rotatably disposing a rotor attached to a drive shaft driven by an engine in a case hermetically filled with a high viscosity fluid, a storage chamber is provided inside the rotor. the torque transmission chamber and the storage chamber are connected through an inlet and an outlet, and the rotor is equipped with an inertia-operated valve that closes the outlet in response to sudden acceleration of the rotor. A fluid joint control device for a cooling fan, characterized by: