JPH036374B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a fluid coupling used in a drive device for a cooling fan device of an internal combustion engine, etc., which uses a fluid medium to transmit torque between relatively rotating input and output members.

Traditionally, it consists of a body member and a cover member,
an output member that forms a working fluid storage chamber and a working chamber; an input member that is located in the working chamber and forms a fluid shearing space between the output member and is rotatable relative to the output member; A fluid coupling has been proposed which increases or decreases the torque transmitted from the input member to the output member via the fluid by increasing or decreasing the amount of fluid in the working chamber, particularly in the shearing space.

In this type of fluid coupling, the storage chamber is located on the side surface of the working chamber, and communication holes with the storage chamber are opened at the inner and outer peripheries of the working chamber, respectively. Here, the communication hole closer to the inner circumference acts as a supply passage for fluid from the storage chamber to the working chamber, and the communication hole closer to the outer circumference acts as a discharge passage for fluid from the work chamber to the storage chamber. In addition, near the outer periphery of the work chamber, a pump section consisting of protrusions extending from the output member toward one end surface of the input member is provided with a phase angle of approximately 180° in order to efficiently discharge the fluid within the work chamber. The fluid thus supplied from the storage chamber to the working chamber acts as a torque transmission medium between the input and output members in the working chamber, and then is directed toward the outer periphery of the working chamber by centrifugal force, and the fluid is provided there. The liquid is circulated to the storage chamber via the pump section.

By the way, in the conventional example, when the fan swings from side to side during idling in a high-speed engine rotation range, an excessive load is applied to the bearing of the output member, etc., which significantly deteriorates the durability of the bearing. .

By the way, when the fan swings left and right like this, the volume between the body members and the cover member near the outer periphery of the work chamber inevitably changes, and the fluid flows from the side with the smaller volume to the side with the larger volume. . In other words, as long as the fluid is incompressible such as liquid,
In order for the fan to swing from side to side, it is essential that fluid circulates as the volume changes between the body member near the outer periphery of the work chamber and the cover member. Therefore, by restricting the flow of fluid, it is possible to prevent the fan from swinging from side to side. It becomes possible to suppress it.

However, in conventional fluid couplings, only the small clearance part between the tip of the protrusion forming the pump part and the input member acts to suppress vibration of the fan due to fluid flow resistance (restriction); Because fluid flow resistance does not work in the large clearance area between the cover member and the body member, the vibration suppression effect of the fan during idle rotation is incomplete, and the fan swings during idle rotation and may cause damage to output members, etc. This results in an excessive load being applied to the bearing, resulting in a disadvantage that the durability of the bearing is significantly deteriorated.

The present invention has been made for the purpose of eliminating the above-mentioned conventional drawbacks, and the gist of the present invention is to provide a cover member with a pump, which is located near the opening end of the working chamber of the communication hole and extends into the working chamber. In addition to the plurality of protrusions for forming the part, a protrusion for forming the anti-shake part is provided between these protrusions and extends into the working chamber, and a small clearance part is formed between the protrusion and the input member. In the clearance part as well, as in the case of the protrusion for forming the pump part, the effect of suppressing vibration of the fan due to the flow resistance of the fluid is exerted.

Embodiments of the present invention will be described in detail below based on the drawings.

FIG. 1 is a cross-sectional view showing an example in which the fluid coupling according to the present invention is applied as a drive device for a cooling fan device for an internal combustion engine, and 1 is an input shaft having a flange portion 2 and a shaft portion 3; It is fixed to the outer engine side, and an input member 4 is fixed to the tip of the shaft portion 3.

5 is a body member which is rotatably attached to the input shaft 1 via a bearing 6, and 7 is a cover member, which forms an annular chamber 8 between opposing inner surfaces, and whose outer periphery is secured by bolts 9... and are fixed to each other to form an output member. The annular chamber 8 is divided into a working chamber 12 by a partition plate 10 that is fixed to the cover member 7 and has left and right communication holes 10a, and a valve plate 11 that can cover and close the communication hole 10a. It is separated from the storage room 13. 14 is a communication hole provided in the cover member 7 and communicating the working chamber 12 and the storage chamber 13.

Reference numeral 15 denotes a spiral bimetal as a temperature-sensitive member, the outer peripheral end of which is fixed to the cover member 7, and the inner peripheral end of which is fixed to one end of a center pin 16 rotatably attached to the cover member 7. , the other end of the center pin 16 is fixed to the valve plate 11. Thus, the valve plate 11 rotates about the center pin 16 in response to the operation of the bimetal 15 in response to changes in ambient temperature, thereby opening and closing the communication hole 10a of the stop plate 10.

The input member 4 is rotatably mounted in the working chamber 12, and the input member 4 has a continuous hole 17 near the center and a through hole 18 near the outer periphery, which communicate from side to side. There is. Each of the facing surfaces of the input member 4 and the body member 5 has a plurality of annular grooves 4a,
5a is provided, forming a shearing space designated S.

Further, the communication hole 1 provided in the cover member 7
4, two protrusions 19 in the direction of the working chamber 12 are provided near the opening end in the working chamber 12, as shown in FIGS. 2 and 3, and form a pump section to be described later. The tip of the projection 19 and the input member 4
A small clearance portion 20 is formed between them. 2
Reference numeral 1 denotes two protrusions for forming a vibration suppressing portion that are located between the protrusions 19 and 19 and extend into the working chamber 12, and between the tip of the protrusion 21 and the input member 4,
A small clearance portion 22 similar to that of the projection 19 for forming the pump portion is formed. A fan blade 23 is fixed to the body member 5 and the cover member 7, which are output members, with bolts 24.

In this configuration, the storage chamber 13 is filled with a desired amount of working fluid, and when the input member 4 is rotated via the input shaft 1 by an engine (not shown) and the ambient temperature near the bimetal 15 rises, the bimetal 15 responds to this, rotates the valve plate 11 via the center pin 16, and connects the communication hole 10 provided in the partition plate 10 by the valve plate 11.
The cover of a is gradually released and opened to allow the fluid in the storage chamber 13 to flow into the working chamber 12, thereby filling the shearing space S with the fluid. Here, the torque transmitted from the input member 4 to the output member body member 5 and cover member 7 is expressed as a function of the amount of fluid in the working chamber 12, particularly as a function of the amount of fluid in the shear space S. Therefore, the fan blades 23 fixed to the body member 5 and the cover member 7, which are output members, increase their rotational speed as the flow fills the shear space S, thereby cooling the engine. Subsequently, the fluid in the working chamber 12 is directed toward the outer periphery of the working chamber 12 by centrifugal force and flows into the pump section. Then, since the input member 4 is rotating in the direction of the arrow X shown in FIG. The fluid in the working chamber 12 flows through the communication hole 14 to the storage chamber 13 , where the pressure is increased, that is, the fluid in the working chamber 12 is pumped.
sent inside.

On the other hand, when the ambient temperature near the bimetal 15 decreases, the bimetal 15 reacts to it, closes the communication hole 10a of the partition plate 10 by closing the valve plate 11, and cuts off the supply of fluid from the storage chamber 13 to the working chamber 12. . Therefore, the fluid in the working chamber 12 is stored in the storage chamber 13 by the pump action, the amount of fluid in the shearing space S is reduced, and the rotational speed difference between the input member 4 and the output members 5, 7 is reduced. increases, and the fan blade 23 rotates at idle,
The vibration of the fan during the idle rotation is caused by the tip of the protrusions 19, 19 forming the pump part and the input member 4.
a small clearance part 20 between the two, and a protrusion 2 for forming a vibration suppressing part provided between these protrusions 19, 19.
This is reliably inhibited by the flow resistance when the fluid communicates through the small clearance portion 22 between the tips of the tips 1 and 21 and the input member 4.

As explained above, the present invention comprises a body member and a cover member, which form a working fluid storage chamber and a working chamber, and an output member having a communication hole opening between the two chambers, and an output member located in the working chamber. In the fluid coupling, which includes an input member that is rotatable relative to the output member, and transmits torque between the input and output members via fluid in the working chamber, the cover member has a hole in the communication hole. A plurality of protrusions are provided near the opening end of the working chamber and extend into the working chamber for forming a pump part, and a plurality of protrusions are provided between these protrusions and extend into the working chamber to form a vibration suppressing part, and these protrusions and Since a small clearance part is provided between the input members, the increase in flow resistance due to the presence of these protrusions reliably suppresses the vibration of the fan during idle rotation, and prevents wear and tear on the bearings as much as possible. Can be done.

[Brief explanation of the drawing]

FIG. 1 is a sectional view showing an embodiment of the present invention as a driving device for a cooling fan device, FIG. 2 is a front view of the inside of a cover member, FIG. 4 is a sectional view taken along the - line in FIG. 3, FIG. 5 is a sectional view taken along the - line in FIG. 3, and FIG. 6 is a sectional view taken along the - line in FIG. 4...Input member, 5...Body member (output member), 7...Cover member (output member), 12...Working chamber, 13...Storage chamber, 14...Communication hole, 19,
21... Protrusion.

Claims (1)

[Claims] 1 consisting of a body member and a cover member, forming a working fluid storage chamber and a working chamber, an output member having a communication hole opening between the two chambers, and an output member located in the working chamber and rotating relative to the output member. In the fluid coupling that transmits torque between the input and output members via the fluid in the working chamber, the cover member includes a movable input member near the opening end of the working chamber of the communication hole. , a plurality of protrusions extending into the working chamber for forming a pump part and a protrusion extending between these protrusions and forming a vibration suppressing part extending into the working chamber are provided, and a small clearance part is provided between these protrusions and the input member. A fluid coupling characterized by: