JP2002180832A - Fluid type fan-coupling device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a temperature-sensitive fluid type fan-coupling device capable of exerting a proper control function by following the ambient temperature vibration, and improving heat radiation to the outside to restrain oil temperature rise due to heat, and to eliminate viscosity lowering of oil. SOLUTION: The inside of a housing comprising a cover 3 and a case with a cooling fin installed on the outer surface of supporting it with a bearing is portioned into an oil storage chamber and a torque transmission chamber for incorporating a drive disc by a partition plate. A dam and a discharge passage continuing to it and communicating with the oil storage chamber from the torque transmission chamber is formed on a part of the inside wall surface of the housing facing to the circumferential wall part of the drive disc for gathering the oil during its rotation, and the cooling fin 15 provided with a valve for closing the feed adjustment hole of the partition plate in its inside and composed of plural heat radiation fins 5a projected at a desired interval so as to draw a curve like an impeller of a pump toward the outside end part from the center side of the housing is formed on one side surface of the housing.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention generally relates to a fluid fan for controlling the rotation of a fan for cooling an engine in an automobile, and supplying a cooling air flow to the engine constantly according to an external temperature.
The present invention relates to an improvement in a coupling device.

[0002]

2. Description of the Related Art Conventionally, this type of fan coupling device includes a temperature-sensitive type, a torque limit type, and an external control type. Examples of the temperature-sensitive type include a cover and a case in which cooling fins are protruded on the outer surface. Partitioning the interior of the housing consisting of an oil sump chamber and a torque transmission chamber that houses the drive disk by a partition plate having an oil supply adjustment hole,
A dam is formed on a part of the inner peripheral wall of the housing opposed to the outer peripheral wall of the drive disk in which oil is collected during rotation, and a circulation discharge passage is formed from the dam and connected to the oil reservoir from the torque transmission chamber side. A valve member for opening the supply adjusting hole of the partition plate when the temperature of the outside ambient exceeds a set value, and closing the supply adjusting hole of the partition plate when the temperature is equal to or less than the set value, the drive disk, the case, and the cover. There is a method of controlling the transmission of torque from the rotating shaft side to the driven side housing side by increasing or decreasing the effective contact area of the oil in the torque transmission gap provided on the opposing wall near the outside. The torque limit type has the same basic structure as that of the temperature-responsive fan / coupling device, but does not have a valve member for opening and closing the supply adjusting hole of the partition plate according to the temperature of the external environment. Is a fan coupling device. On the other hand, the external control type is a system in which a valve member for opening and closing the supply adjustment hole of the partition plate is made of a magnetic material, and the valve member having the magnetism is controlled by an electromagnet provided outside. The interior of the housing consisting of a cover and a case with cooling fins protruding on the outer surface is partitioned into an oil sump chamber and a torque transmission chamber containing a drive disk by a partition plate having an oil supply adjustment hole. A dam is formed on a part of the inner peripheral wall surface of the housing opposed to the outer peripheral wall portion of the drive disk in which the oil is collected, and a circulating discharge path connected to the dam and extending from the torque transmission chamber side to the oil reservoir chamber is formed. An outflow adjustment path leading from the reservoir chamber to the torque transmission chamber side is formed, and the effective contact area of oil in the torque transmission gap formed by the opposing surface between the built-in drive disk and the housing is increased / decreased, and driven from the rotating shaft side. ~ side With a mechanism for controlling the transmission of torque to the housing side, a pair of electromagnets provided on the front side or the rear side of the housing, a valve member having magnetism that opens and closes the outflow adjustment path facing one of the electromagnets, In addition, there is a type in which a sub-valve member having magnetism for opening and closing the circulation discharge path is provided opposite to the other electromagnet.

[0003] The structure of the cooling fins in the above-mentioned temperature-responsive, torque-limit type, and external control type fan coupling devices is, as shown in FIGS. And flat plates 35a and 35b provided in a radial straight line toward the cover 3 and projecting outward from the cover 3 or the case 2.

[0004] However, such a conventional drive disk-based fan coupling device prevents oil from flowing out of a torque transmission gap formed by the inner peripheral portion of the housing and the outer peripheral portion of the drive disk during rotation operation. Since the operation is performed by the centrifugal force accompanying the rotation of the drive disk, the oil in the torque transmission gap is constantly sheared and generates heat, and this heat is transmitted to the cover or the case. With the conventional cooling fins formed of flat cooling fins that are linearly provided from the vicinity of the center of the case to the outer periphery, there are few edges (edges),
Edge effect (separation of boundary layer) due to simple flow of cooling air flowing only radially between the cooling fins
Insufficient heat dissipation to the outside because insufficient boundary layer is hardly peeled off, insufficient heat dissipation to the outside, the oil temperature rises and the viscosity decreases, so it is appropriate to follow the temperature change around the outside Cause inconsistency in various control functions,
There has been a problem that the service life may be shortened due to deterioration of the oil and the bearing, resulting in poor reliability.

[0005]

SUMMARY OF THE INVENTION The present invention has been proposed in view of the above-mentioned problems, and has a number of cooling fin edges provided to increase the edge effect and to radiate heat to the outside well. Minimizing oil temperature rise due to heat generation, eliminating concerns about oil deterioration, viscosity decrease, and bearing deterioration. It is an object of the present invention to provide a fluid-type fan coupling device having a high cost and a long life.

[0006]

SUMMARY OF THE INVENTION In order to achieve the above object, the present invention provides a rotary shaft having a drive disk fixed to a tip end thereof, which is supported via a bearing and has a cooling fin protruding from an outer surface. The interior of the housing consisting of the cover and the case is partitioned into an oil sump chamber and a torque transmission chamber housing the drive disk by a partition plate having an oil supply adjusting hole,
A dam is formed on a part of the inner peripheral wall surface of the housing facing the outer peripheral wall portion of the drive disk in which oil is collected during rotation, and a circulation discharge passage is formed in connection with the dam and communicates from the torque transmission chamber side to the oil reservoir chamber. Fluid type fan coupling device,
A plurality of short radiating fins protruding at a desired interval on at least one side of the housing from the center side of the housing toward the outer end from the center side of the housing so as to draw a curve similar to the impeller of the pump. SUMMARY A fluid fan coupling device having a cooling fin having a number of edges is featured. The short heat radiation fins constituting the cooling fins may have any one of a cross-sectional shape of a circle, an ellipse, an oval, a cross-sectional shape of a blade, a wedge, a rectangle, and an arc. Further, the short radiating fins constituting the cooling fins may be arranged alternately with their phases shifted alternately so as to draw a curve similar to that of the impeller of the pump.

In the present invention, a plurality of cooling fins provided on the housing are intermittently protruded from a center side of the housing toward an outer end portion at desired intervals so as to draw a curve similar to that of an impeller of a pump. With the short radiating fins, the external cooling air flows not in the radial direction but in the shape of an arc so as to follow the same curve as the pump impeller, due to the rotational movement of the housing provided with the cooling fins. The boundary layer is separated by the collision between the flow and each edge of the cooling fins intermittently (edge effect), thereby increasing the heat transfer between the two, and consequently improving the heat radiation effect of the cooling fins, This is for further suppressing the temperature rise of the torque transmitting oil filled in the housing. The length of the short radiating fin is not particularly limited, but is at least about 1 to 10 times the average thickness of the cooling fin. The length and interval of the heat radiation fins are 2 to 2 respectively.
It is about 0 mm and 3 to 10 mm.

According to the present invention, a row of fins composed of short radiating fins having an edge is spaced from the vicinity of the center of the housing toward the outer end so as to draw a curve similar to that of the impeller of the pump. By the edge action of the arranged cooling fins, it is possible to further suppress the temperature rise of the torque transmitting oil filled in the housing, so that there is no concern about deterioration of the oil, viscosity decrease, and bearing deterioration. The present invention can provide a fluid fan / coupling device which exhibits an appropriate control function and has a long service life and high reliability by following the temperature change.

[0009]

FIG. 1 is a longitudinal sectional view showing an embodiment of a fluid type fan coupling device according to the present invention, and FIG. 2 is a view partially showing a cooling fin on a cover side in the fan coupling device. FIG. 3 exemplifies a cross-sectional shape of the cooling fin, and FIG. 3A is a front view showing a part of a cooling fin configured by a circular heat radiation fin.
(B) is a front view showing a part of the cooling fins formed by elliptical heat radiation fins, (c) is a front view showing a part of the cooling fins formed by elliptical heat radiation fins, and (d) is a wing of the wing. (E) is a front view showing a part of a cooling fin formed of a wedge-shaped or water-drop-shaped radiating fin; (f) is a front view showing a part of a cooling fin formed of a radiation fin having a cross-sectional shape; Front view showing a part of a cooling fin configured by fins,
(G) is a front view showing a part of a cooling fin formed by a square-shaped heat radiation fin, (h) is a front view showing a part of a cooling fin formed by an arc-shaped heat radiation fin, and FIG. b)
(C) is a partial plan view showing another embodiment of the cooling fin, FIG. 5 is a partial longitudinal sectional view showing another embodiment of the fluid fan coupling device according to the present invention, and FIG. FIG. 5 is a partial vertical sectional view showing another embodiment of the fluid fan coupling device according to the present invention.

The fluid-type fan coupling device shown in FIG. 1 is a temperature-sensitive type, and 1 is a rotary shaft having a drive disk fixed to the tip thereof. A housing comprising a cover 3 having a cooling fan (not shown) mounted on the outer periphery is supported. 5
The oil reservoir 6 and the drive disk 7
Is a partition plate partitioned into a torque transmission chamber 4 in which
On the partition plate, an oil supply adjusting hole 5 ′ from the oil sump chamber 6 to the torque transmission chamber 4 is provided. Further, the drive disk 7 is provided in the torque transmission chamber 4 and has a small gap for transmitting torque between the drive disk 7 and an opposing wall surface of the housing near the outside thereof. Numeral 8 is a valve member for opening and closing the supply adjusting hole 5 '. One end of the valve member is attached to the partition plate 5 on the oil sump chamber 6 side, and the other end is provided so as to face the supply adjusting hole. The support member 11 fixed to the front surface of the cover 3 has a support member 11 fixed at both ends thereof. It is prepared for. Numeral 12 denotes a dam provided on a part of the inner peripheral wall of the housing facing the outer peripheral wall of the drive disk 7 for collecting oil during rotation, and a torque transmission chamber near the dam in the rotation direction. A circulation discharge passage 13 is formed from the side 4 to the oil sump chamber 6 side, and has a pumping function. Numeral 15 is a cooling fin composed of a number of short radiating fins 15a having edges projecting from the case 2 and the cover 3 constituting the housing at intervals so as to draw a curve similar to that of the pump impeller. It is formed by molding an aluminum alloy or the like by an appropriate method such as die casting or casting.

As shown in FIG. 2, a cooling fin 15 in the temperature-responsive fluid-type fan coupling device shown in FIG. 1 is provided with a short radiating fin 15a on a case 2 and a cover 3 constituting the housing. Are arranged intermittently at intervals so as to draw a curve similar to that of the pump impeller from the vicinity of the center toward the outer end. Here, the thickness t, height h, length w, and interval l of each radiation fin 15a are t = 2 mm, h = 10 mm on the center side, 20 mm on the outer peripheral side, w = 10 mm, l
= About 4 mm.

In the case of the temperature-responsive fluid-type fan coupling device having the cooling fins 15 having the above structure, it is intermittently projected at intervals so as to draw a curve similar to that of the pump impeller over the entire surface of the housing. Due to the action of the large number of short heat radiation fins 15a having the bent edges, an arc-shaped flow is generated in the external cooling air with the rotation of the housing provided with the cooling fins 15, and a large number of intermittent flow with the arc-shaped flow are generated. Collision of the cooling fins 15 with each edge improves the heat transfer efficiency to the external cooling air, thereby increasing the heat radiation effect from the cooling fins 15 and preventing the temperature of the torque transmitting oil filled in the housing from rising. Eliminates concerns about oil deterioration, viscosity reduction, and bearing deterioration,
Various excellent characteristics can be obtained, such as exhibiting an appropriate control function by following the temperature change of the external environment for a long time. The type of the sensing method does not matter.

Next, the cooling fin 15 according to the present invention will be described.
Various shapes will be described with reference to FIG. (A) is a cooling fin configured by projecting radiation fins 15a-1 having a circular cross section at intervals so as to draw the same curve as the impeller of the pump. The diameter of the radiation fin 15a-1 is 2.
About 8 mm. (B) is a cooling fin configured by projecting short heat radiation fins 15a-2 having an elliptical cross section at intervals so as to draw a curve similar to that of an impeller of a pump. (C) is a cooling fin configured by protruding a short radiating fin 15a-3 having an oblong plane shape at intervals so as to draw a curve similar to that of an impeller of a pump. (D) is a cooling fin formed by projecting short heat radiation fins 15a-4 having a plane sectional shape of a blade at intervals so as to draw a curve similar to that of an impeller of a pump. The leading edge protrudes toward the center of rotation. (E) is a cooling fin configured by projecting short heat radiation fins 15a-5 having a water droplet shape or a wedge shape in plan view at intervals so as to draw a curve similar to that of an impeller of a pump. The wider one projects inward. (F) is a short heat radiation fin 1 having a rectangular planar shape.
5a-6 are cooling fins formed by protruding at intervals so as to draw the same curve as the impeller of the pump,
(G) is a short radiation fin 15a having a square planar shape.
-7 are cooling fins formed by projecting at intervals so as to draw a curve similar to that of the impeller of the pump. (H)
Are cooling fins formed by projecting short radiation fins 15a-8 having an arc shape in plan view at intervals so as to draw the same curve as the impeller of the pump.

Each of the cooling fins shown in FIGS. 3 (a) to 3 (h) generates an arc-shaped flow in the external cooling air as the housing provided with the cooling fin 15 rotates. The efficiency of heat transfer from the cooling fins 15 to the external cooling air is improved by colliding the heat radiation fins with various cross-sectional shapes having intermittent edges to change the flow, and as a result, the heat radiation effect from the cooling fins 15 is improved. The effect of increasing is obtained. These radiation fins may be used in an appropriate combination.

The cooling fins shown in FIG. 4 exemplify a configuration in which radiation fins are alternately arranged with a phase shift. FIG. 4A shows a short fin having an oblong plane shape shown in FIG. Are arranged such that the phase of the radiation fins 15a-3 is alternately shifted over a certain width and the phase difference is gradually reduced, and FIG. 3 (b) shows a short radiation having a square planar shape shown in FIG. This is an example in which the fins 15a-7 are alternately shifted in phase over a certain width from the rotation center side and the phase difference is gradually reduced, and FIG. This is an example in which the phases are alternately shifted from the rotation center side and the phase difference is gradually increased, and in the case of cooling fins in a so-called staggered arrangement,
Along with the rotation of the cooling fins 15, the laminar arc-shaped flow generated for each cooling fin collides with the edges of the radiating fins having various intermittent cross-sections to change the flow and change the phase. As a result, the heat transfer efficiency from the cooling fins 15 to the external cooling air can be further improved, and the heat radiation effect can be further enhanced.

The fluid type fan coupling device shown in FIG. 5 is of a torque limit type, and its basic structure is the same as that of the temperature sensitive type fan coupling device.
This type of fan coupling device does not have a valve member for opening and closing the supply adjusting hole of the partition plate according to the temperature of the external environment. The structure of the drive disk 27
Case 22 via a bearing B on a rotating shaft 21 to which
And a cover 23 having a cooling fan (not shown) attached to the outer periphery.
The interior of the housing is partitioned by a partition plate 25 into an oil sump chamber 26 and a torque transmission chamber 24 that houses the drive disk 27. The partition plate 25 has a torque from the oil sump chamber 26. Oil supply hole 2 to transmission chamber 24
5 'is provided. Further, the drive disk 27
Is located in the torque transmission chamber 24 and has a minute gap for transmitting torque between the outer wall and the opposing wall surface of the housing near the outside. 32 is a drive disk 2 for collecting oil during rotation
7 is a dam provided on a part of the inner peripheral wall surface of the housing facing the outer peripheral wall portion, and is circulated and discharged from the torque transmission chamber 24 side to the oil sump chamber 26 side in front of the dam in the rotation direction. The path 33 is formed to have a pumping function. Reference numeral 35 denotes a cooling fin comprising a large number of short radiating fins 35a having edges protruding from the case 22 and the cover 23 constituting the housing. It is formed by an appropriate method.

In the case of the torque limit type fluid fan / coupling device, an arc-shaped flow is generated in the external cooling air in accordance with the rotation of the housing provided with the cooling fins 35. The efficiency of heat transfer to the external cooling air is improved by intermittent collisions with a large number of cooling fins 35 having the bent edges.
5 to improve the heat dissipation effect, prevent the temperature of the oil for torque transmission filled in the housing from rising, eliminate the fear of oil deterioration, viscosity decrease, and bearing deterioration, and prevent external ambient temperature changes for a long time. Following this, various excellent characteristics, such as exerting an appropriate control function, can be obtained. Needless to say, the present invention can be applied to a torque limit type coupling having a further simplified structure by omitting the partition plate 5, the dam 12, and the circulation discharge path 13.

The fluid type fan coupling device shown in FIG. 6 is of an external control type, and its structure is the same as that of the temperature sensitive type fan coupling device. The valve member that opens and closes the supply adjustment hole of the partition plate that partitions into the torque transmission chamber that houses the magnetic member is made of a magnetic material, and the valve member having the magnetism is controlled by an electromagnet provided outside. A housing consisting of a case 42 and a cover 43 on the outer periphery of which a cooling fan (not shown) is mounted is supported via a bearing B on a rotating shaft 41 to which a drive disk 47 is fixed, and a partition plate 45 is provided inside the housing. The oil reservoir 46 and the drive disk 4
7 is divided into a torque transmission chamber 44 in which
5 is provided with an oil supply adjusting hole 45 ′ from the oil reservoir chamber 46 to the torque transmission chamber 44. The drive disk 47 is located in the torque transmission chamber 44 and has a small gap for torque transmission between the drive disk 47 and the opposing wall surface of the housing near the outside thereof. Numeral 52 is a dam provided on a part of the inner peripheral wall of the housing facing the outer peripheral wall of the drive disk 47 for collecting the oil during rotation. A circulation discharge passage 53 is formed from the 44 side to the oil sump chamber 46 side, and has a pumping function. A valve member 48 has one end attached to the partition plate 45 on the oil sump chamber 46 side, the other end is positioned at the supply adjustment hole 45 ', and a magnetic piece 49 is attached to the intermediate portion. The supply adjusting hole 45 'is opened and closed according to the presence or absence of an exciting current to a concentric circular ring-shaped electromagnet 50a provided at a position facing the magnetic piece 49 on the front side of the housing. Further, an auxiliary valve member 56 made of a magnetic material
The outlet of the circulation discharge passage 53 is opened and closed by the action of a ring-shaped electromagnet 50b provided on the front side of the housing in opposition to the slide valve.
The central portions of the pair of ring-shaped electromagnets 50a and 50b are attached via a bearing B to a support shaft 51 provided at the center of the outside of the housing, and the other is fixed to a part of the vehicle body or the like. 55 is a cooling fin composed of a number of short radiating fins 55a having edges protruding from the case 42 and the cover 43 constituting the housing. It is formed by an appropriate method.

Also in the case of the above-mentioned external control type fluid fan coupling device, an arc-shaped flow is generated in the external cooling wind with the rotation of the housing provided with the cooling fins 55, and the arc-shaped flow is intermittent. Collision with a large number of cooling fins 55 having an edge improves heat transfer efficiency to the external cooling air, thereby increasing the heat radiation effect from the cooling fins 55 and increasing the temperature of the torque transmitting oil filled inside the housing. To prevent various problems such as oil deterioration, viscosity decrease, and bearing deterioration. You can. In the case of this external control type, the control method does not matter.

Although the cooling fins 15, 35, 55 are shown on both the cases 2, 22, 42 and the covers 3, 23, 43, in the present invention, the cooling fins 15, 35, 55 are provided on either side of the housing, ie, the case or the case. It is important to project one of the covers, and if both are projected, the heat dissipation effect is further improved.

[0021]

As described above, according to the present invention, a row of fins composed of short radiating fins having edges draws a curve similar to that of an impeller of a pump from the vicinity of the center of the housing toward the outer end. With the rotation of the cooling fins arranged at intervals as described above, an arc-shaped flow was generated in the external cooling wind flowing over the entire surface of the housing and flowing in contact with the surface of the cooling fin, and the arc-shaped flow was interrupted. The edge effect of intermittently colliding the edges of the radiating fins with various cross-sectional shapes with the external cooling air improves the efficiency of heat transfer from the cooling fins to the external cooling air, resulting in a reduction in the amount of heat released from the cooling fins. As it can be increased, there is no concern about deterioration of the torque transmission oil filled in the housing or reduction in viscosity, and furthermore, deterioration of the bearings is prevented. Along with the temperature change of the external environment, the proper control function can be exhibited, and the service life of the fan coupling device can be extended and the reliability can be improved. The device has many excellent effects that the size and weight of the device can be reduced and the cost can be reduced.

[Brief description of the drawings]

FIG. 1 is a longitudinal sectional view showing one embodiment of a temperature-responsive fluid-type fan coupling device according to the present invention.

FIG. 2 is a front view showing a cooling fin on a cover side in the fan coupling device according to the first embodiment;

FIGS. 3A and 3B show examples of the cross-sectional shape of the cooling fin, in which FIG. 3A is a front view showing a part of the cooling fin formed of a circular radiating fin, and FIG. Front view showing a part of the cooling fins, (c) front view showing a part of the cooling fins constituted by oblong radiation fins,
(D) is a front view showing a part of a cooling fin formed by a radiation fin having a wing cross-sectional shape, (e) is a front view showing a part of a cooling fin formed by a water-drop-shaped radiation fin, and (f) is a front view. (G) is a front view showing a part of a cooling fin formed of a square-shaped heat radiation fin; (h) is a front view showing a part of a cooling fin formed of a rectangular heat radiation fin; It is a front view which shows some cooling fins comprised.

FIG. 4 is a partial front view showing another embodiment of the cooling fin of the present invention, and FIG. 4 (a) is a cross-sectional shape shown in FIG. The cooling fins are arranged, (b) is a cooling fin in which short heat radiation fins having a square cross section as shown in FIG. 3 (g) are alternately arranged with a phase shift, and (c) is also shown in FIG. 3 (g). Cooling fins in which short heat radiating fins having a square cross section are alternately arranged with a phase shift opposite to that of FIG.

FIG. 5 is a partial longitudinal sectional view showing another embodiment of the fluid fan coupling device according to the present invention.

FIG. 6 is a partial longitudinal sectional view showing another embodiment of the fluid fan coupling device according to the present invention.

FIG. 7 is an enlarged partial perspective view showing a conventional cooling fin.

FIG. 8 is an enlarged partial perspective view showing another conventional cooling fin.

[Explanation of symbols]

 1, 21, 41 Rotary shaft body 2, 22, 42 Case 3, 23, 43 Cover 4, 24, 44 Torque transmission chamber 5, 25, 45 Partition plate 6, 26, 46 Oil sump chamber 7, 27, 47 Drive disk 8, 48 Valve member 9 Connecting rod 10 Thermosensitive body 12, 32, 52 Dam 13, 33, 53 Circulation discharge path 15, 35, 55 Cooling fin 15a, 35a, 55a Short radiating fin 15a-1 Cross section of circular shape Radiation fin 15a-2 Radiation fin with elliptical cross section 15a-3 Radiation fin with oval cross section 15a-4 Radiation fin with wing cross section 15a-5 Radiation fin 15a-6 with wedge cross section Radiation fin 15a-7 having a rectangular cross section 15a-8 Radiation fin 15a-8 having a square cross section 50a, 50b Electromagnet B bearing

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[Procedure amendment]

[Submission date] December 21, 2000 (200.12.
21)

[Procedure amendment 1]

[Document name to be amended] Drawing

[Correction target item name] Fig. 1

[Correction method] Change

[Correction contents]

FIG.

[Procedure amendment 2]

[Document name to be amended] Drawing

[Correction target item name] Fig. 5

[Correction method] Change

[Correction contents]

FIG. 5

Claims (3)

[Claims] An oil supply adjustment is performed on the inside of a housing consisting of a cover and a case, which are supported via bearings on a rotating shaft body having a drive disk fixed to the end thereof, and which are provided with cooling fins on the outer surface thereof. A part of an inner peripheral wall surface of a housing which is partitioned by a partition plate having a hole into an oil reservoir and a torque transmission chamber which houses the drive disk, and which faces an outer peripheral wall of the drive disk in which oil is collected during rotation. A dam, and a fluid-type fan coupling device formed with a circulation discharge passage that communicates with the oil reservoir chamber from the torque transmission chamber side, wherein the cooling fin is provided on at least one side surface of the housing. A fluid comprising a plurality of short radiating fins projecting at desired intervals so as to draw a curve similar to that of an impeller of a pump from a center side to an outer end portion. Type fan coupling device. 2. The short radiating fins constituting the cooling fins have any one of a cross-sectional shape of a circle, an ellipse, an oval, a wing, a wedge, a rectangle, and an arc. The fluid fan coupling device according to claim 1, wherein 3. The cooling fin according to claim 1, wherein the short radiating fins constituting the cooling fin are alternately arranged with a phase shifted so as to draw a curve similar to that of the impeller of the pump. 3. The fluid-type fan coupling device according to 2.