JP2505406Y2 - Fan coupling for internal combustion engine - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Application] The present invention relates to a fan coupling for an internal combustion engine used to drive a cooling fan of the internal combustion engine.

[Prior Art] Generally, a fan coupling for an internal combustion engine is used to change the number of rotations of a cooling fan in accordance with the number of engine rotations or the temperature of engine cooling water.

For this reason, the housing is filled with viscous fluid, and the coupling that transmits the rotational force to the housing by rotating the disk driven by the output shaft of the engine in this viscous fluid constitutes the cooling fixed to the housing. The fan is rotating.

Then, by controlling the flow of this viscous fluid by a valve driven by a bimetal, the rotation speed of the housing, and by extension, the cooling fan, is controlled.

Thus, conventionally, as shown in FIG. 5, the bimetal A is spirally wound, the base end portion Aa thereof is fixed to the valve drive shaft B, and the end portion Ab is bent in the radial direction. And is fixed to the housing C.

Thus, the bimetal A controls the flow of the viscous fluid by rotating the valve drive shaft B and thus the valve in accordance with the temperature change (see Japanese Utility Model Laid-Open No. 60-115640).

[Problems to be solved by the device]

However, in such a conventional fan coupling, since the terminal end Ab of the bimetal A is bent (R) in the radial direction and fixed to the housing C,
There was a problem of poor durability.

That is, bimetal usually has an elastic modulus E of 11000.
~ 17000kg / mm ² and 20kg / mm ² when the allowable stress is 100 ℃
And has its own natural frequency. By the way, the internal combustion engine has a wide range of rotation speed, and its vibration increases as the rotation speed increases, but the fan coupling is also affected by the vibration, so that the bimetal resonates within the rotation speed range. Then, the bimetal may be broken at the radial bending portion R, which has the weakest strength.

SUMMARY OF THE INVENTION An object of the present invention is to solve the above conventional problems and provide a fan coupling for an internal combustion engine which is excellent in durability without breaking the bimetal even if resonance occurs.

[Means for solving the problem]

In order to achieve the above object, the present invention provides an internal combustion engine in which a base end of a spirally wound bimetal is fixed to a drive shaft of a valve, and an end of the bimetal is fixed to a housing via a support member. In the fan coupling for use, the end portion of the bimetal is formed in an arc shape like the base end portion, the support member is formed with a bent portion, and one end portion of the support member is fixed to the housing, The other end was superposed on and fixed to the end of the bimetal.

[Action]

According to the present invention, the end portion of the bimetal is formed in an arc shape like the base end portion, and the bent portion is formed in the support member. One end portion of the support member is fixed to the housing and the other end portion is fixed. As a result of overlapping and fixing to the end portion of the bimetal, it is possible to eliminate the bent portion in the radial direction, which is susceptible to vibration, on the end portion side of the bimetal. Therefore, even if resonance occurs, the bimetal Will not be broken.

〔Example〕

Hereinafter, embodiments of the present invention will be described with reference to the accompanying drawings.

 1 and 2 show an embodiment of the present invention.

In the figure, reference numeral 1 is a rotary shaft driven by an output shaft of an engine, and a disk member 2 having concentric concavo-convex grooves formed at its outer edge is fixed to the tip end of the rotary shaft.

Reference numeral 3 denotes a housing which surrounds the disk member 2, and is constituted by connecting a base housing 3A supported by the rotary shaft 1 via a bearing 4 and a cover housing 3b. Concentric concavo-convex grooves are also formed in the cover housing 3b, and the labyrinth 5 is constituted by alternately engaging with the concavo-convex grooves of the disk member 2.

Further, the cover housing 3B is fixedly provided with a partition wall 6 that covers the recessed portion at the center thereof, and defines a drive chamber 7 in which the disk member 2 is present and a storage tightening 8. The partition wall 6 is formed with first and second viscous oil inflow holes 6A and 6B and a viscous oil outflow hole 6C. The cover housing 3B is formed in the recess where the first viscous oil inflow hole 6A is opened. A communication passage 9 is provided, one end of which is open to the discharge pump portion outside the labyrinth 5 described above.

10 is a valve body that opens and closes the viscous oil outflow hole 6C, and is a valve drive shaft rotatably supported by the cover housing 3B.
It is fixed at 11.

The valve drive shaft 11 has a bimetal 12 wound in a spiral shape.
The base end of the support member 13 is fixed to the terminal end of the bimetal 12, and the other end of the support member 13 whose one end is fixed to the cover housing 3B is overlapped and fixed by welding as shown in FIG. There is. The support member is made of a metal stronger than the bimetal 12, and has a radial bent portion 13 in the middle abdomen thereof.
Have an A.

The cooling fan (not shown) is attached using a bolt hole formed on the outer edge of the base housing 3A. Also,
Silicon oil or the like is used as the viscous oil.

In the present embodiment having the above-mentioned configuration, the rotary shaft 1 and the disk member 2 rotate as the engine rotates, and the housing 3 and thus the cooling fan rotate with a predetermined slip.

When the temperature is low, the bimetal 12 does not operate, the valve body 10 driven by the bimetal 12 does not operate, and the viscous oil discharge hole 6C is closed.

Therefore, the viscous oil inside is discharged from the discharge pump section to the communication section 9 and the first and second viscous oil inflow holes 6A and 6B by centrifugal force.
Enters the storage room 8 from the labyrinth 5 and leaves only a small amount on the labyrinth 5.

Therefore, the rotation of the engine is also transmitted to the cooling fan only slightly, and the rotation of the cooling fan is suppressed low.

When the temperature rises, the bimetal 12 is displaced and the valve body 10 is rotated via the valve drive shaft 11. Then, the viscous oil outlet 6C is opened, the viscous oil in the storage chamber 8 is filled in the drive chamber 7, and the rotational force required to increase the rotation of the cooling fan is transmitted.

At this time, even if the bimetal 12 vibrates due to the vibration of the engine or resonates at a specific frequency, the bimetal
Since the terminal end portion of 12 is supported by a stronger support member, the bimetal 12 is not broken or the like.

In the above-described embodiment, the support member having a shape along the curvature of the end portion of the spiral bimetal is fixed by welding. As a means for fixing the support member, as shown in FIG. The end portion of the support member may be bent into a U shape and welded or crimped so that they are held together.

Further, as shown in FIG. 4, a support member 13 having a claw 13B on its side edge may be used, and after the claw 13B is brought into close contact with the end of the bimetal 12, the claw 13B may be fixed by bending and caulking. .

[Effect of device]

As is apparent from the above description, according to the present invention, the bent portion is provided on the support member side of the bimetal, and one end portion of the support member is fixed to the housing, and
As a result of overlapping and fixing the other end portion on the end portion of the bimetal, it is possible to eliminate the bent portion on the end portion side of the bimetal, and therefore, without causing breakage of the bimetal,
A durable fan coupling for an internal combustion engine can be obtained.

[Brief description of drawings]

1 is a side sectional view showing an embodiment of the present invention, FIG. 2 is a front view of an essential part of an embodiment of walking, and FIG. 3 is a front view of an essential part of another embodiment of the present invention. FIG. 5 is a front view of a main portion of still another embodiment of the present invention, and FIG. 5 is a front view of the main portion showing a conventional bimetal mounting state. 1 ... Rotating shaft, 2 ... Disk member, 3 ... Housing, 10 ...
Valve body, 11 ... Valve drive shaft, 12 ... Bimetal, 13 ... Support member. 13A ... Bent section

Claims (1)

(57) [Scope of utility model registration request] 1. A fan coupling for an internal combustion engine, wherein a base end of a spirally wound bimetal is fixed to a drive shaft of a valve, and an end of the bimetal is fixed to a housing via a support member. The end portion of the bimetal is formed in an arc shape like the base end portion, and a bent portion is formed in the support member, one end portion of the support member is fixed to the housing, and the other end portion is the end portion of the bimetal. A fan coupling for an internal combustion engine, which is superposed and fixed on a portion.