JP2002115547A - Driving gear of cooler for engine - Google Patents

Abstract

(57) [Problem] To prevent a rotating shaft (1) supporting an impeller (5) and a cooling fan (10) from rotating at an unnecessarily high speed. The fuel consumption of the engine that drives the rotary shaft 1 is reduced, and the durability of the bearing unit 4 that supports the rotary shaft 1 is improved. SOLUTION: A fluid coupling 20 is provided between the rotary shaft 1 and a driven pulley 6a. In this fluid coupling, the transmission efficiency decreases as the rotation speed of the driven pulley 6a increases. Therefore, even when the driven pulley 6a rotates at a high speed with an increase in the rotation speed of the engine, the rotation speed of the rotary shaft 1 does not needlessly increase, and the above-described problem can be solved.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION A driving device for an engine cooling device according to the present invention is provided with a water pump for flowing cooling water through the engine of a vehicle and a heat pump for dissipating the cooling water. It is used to rotationally drive a fan for blowing air to the radiator.

[0002]

2. Description of the Related Art A water pump for flowing cooling water to a front engine / engine for a rear wheel drive vehicle (FR vehicle) and a cooling fan for blowing a radiator for dissipating the cooling water include: It is driven through the belt by the crankshaft of the engine. That is, a belt is stretched between a driving pulley fixed to an end of the crankshaft and a driven pulley fixed to a rotating shaft for rotatingly driving the impeller and the cooling fan constituting the water pump, and The rotation shaft is driven to rotate with the rotation of the shaft.

FIG. 2 shows a driving device for such an engine cooling device. The rotary shaft 1 is rotatably supported at an intermediate portion thereof by a bearing unit 4 supported by a housing 3 of the water pump 2. And the above-mentioned rotating shaft 1
An impeller 5 is provided at a portion located inside the housing 3 at the inner end (right end in FIG. 2), and a driven pulley 6 is provided at a portion located outside the housing 3 at the outer end (left end in FIG. 2). , Each is fixed. A belt 7 is stretched between the driven pulley 6 and a driving pulley fixed to an end of a crankshaft (not shown), so that the rotating shaft 1 can be driven to rotate during operation of the engine. The impeller 5 and the bearing unit 4 are part of the rotating shaft 1.
A mechanical seal 8 is provided between them to prevent the cooling water flowing in the housing 3 from entering the bearing unit 4 side.

On the other hand, a cooling fan 10 is provided on an outer half (left half in FIG. 1) of an inner hub 9 for fixing the driven pulley 6 to an outer end of the rotary shaft 1, and a rolling bearing 11 and a fluid coupling. Support via 12. The rolling bearing 11 and the fluid coupling 12 are arranged on a shaft 13 provided on the outer half of the inner hub 9 concentrically with the rotary shaft 1 in parallel to the power transmission direction. That is, the cooling fan 10
A part of the outer hub 14 provided at the center of the
Is rotatably supported by the rolling bearing 11 at an intermediate portion of the roller. Also, at the outer end of the inner hub 9, a portion protruding outward from the rolling bearing 11 is provided with the fluid coupling 12.
Are fixed to the outside. The space between the rotor 15 and the rolling bearing 11 is filled with a silicone oil 16 which is a viscous fluid.

When the rotating shaft 1 and the inner hub 9 rotate with the operation of the engine, the rotation is based on the bearing torque and the viscosity of the silicone oil 16 and the rotor 15 is rotated.
From the outer hub 14. In this case, the temperature of the part adjacent to the radiator in the engine room is low,
If it is not necessary to increase the amount of air flow through the radiator, the viscous resistance of the fluid coupling 12 does not increase so much, and the cooling fan 10 rotates slowly. On the other hand, when the temperature in the engine room rises, the action of the bimetal 17 allows the silicon oil 16 to pass through the labyrinth portion 18, increasing the viscous resistance of the fluid coupling 12 and increasing the cooling fan 10 rotation speed is increased. In this way, by rotating the cooling fan 10 based on the viscous resistance of the silicone oil 16 in accordance with the temperature in the engine room, the cooling fan 10 can be appropriately rotated regardless of the rotation of the rotating shaft 1.
This prevents excessive increase in the rotation speed of the motor and reduces power consumption.

[0006]

In the case of the conventional driving device for a cooling system for an engine, which is constructed and operates as described above, the rotation speed of the cooling fan 10 with respect to the rotation speed of the rotating shaft 1 can be adjusted. Also, the impeller 5 of the water pump 2
It is not possible to adjust the speed of rotation. For this reason, the amount of cooling water flowing in the water jacket of the engine increases in proportion to the rotation speed of the crankshaft of the engine. On the other hand, the amount of cooling water to be circulated in the water jacket of the engine is not proportional to the rotation speed of the engine. Of course, the higher the rotational speed of the engine, the greater the amount of heat generated by the engine. Therefore, the amount of cooling water that must flow through the water jacket during high-speed rotation, for example, during idling, increases. However, the amount does not become so large as to be proportional to the rotation speed of the engine.

For this reason, in the case of the conventional structure, when the engine is rotating at a high speed, excess cooling water flows through the water jacket. In such a state, the water pump 1 is performing a useless operation, and accordingly, the power loss of the engine is increased and the fuel is wasted. The demand for energy saving in recent years has demanded the development of a technology for eliminating such waste. Moreover, in the above-described state, the rotating shaft 1 rotates at a rotation speed higher than originally required, and the durability of the bearing unit 4 supporting the rotating shaft 1 is reduced accordingly. The drive device of the engine cooling device according to the present invention has been invented in view of the above-described circumstances.

[0008]

A drive device for an engine cooling device according to the present invention drives and rotates a rotary shaft through a transmission member by an engine, similarly to the above-described conventional drive device for an engine cooling device. Based on the rotation of the rotating shaft, an impeller constituting a water pump for flowing cooling water through the engine and a cooling fan for blowing heat to a radiator for lowering the temperature by radiating the cooling water. Drive rotationally. In particular, in the driving device for an engine cooling device according to the present invention, the transmission efficiency from the transmission member to the rotation shaft is reduced between the transmission member and the rotation shaft as the rotation of the transmission member increases. A joint member is provided.

[0009]

According to the driving device for an engine cooling device of the present invention configured as described above, when the engine rotates at a high speed, the rotation speed of the rotating shaft increases in proportion to the rotation speed of the engine. Disappears. That is, the rotation speed is higher when the engine is rotating at a high speed than when the engine is rotating at a low speed, but does not increase in proportion to the rotation speed of the engine. Therefore, the impeller constituting the water pump does not rotate at an unnecessarily high speed, so that the power loss can be suppressed, and the durability of the bearing supporting the rotary shaft can be improved.

[0010]

FIG. 1 shows a first embodiment of the present invention.
An example is shown. The rotary shaft 1 is rotatably supported at an intermediate portion thereof by a bearing unit 4 supported by a housing 3 of the water pump 2. Then, the impeller 5 is located at a position located inside the housing 3 at the inner end (the right end in FIG. 1) of the rotary shaft 1, and is located outside the housing 3 at the outer end (the left end in FIG. 1). Cooling fan 10 in part
Are fixed respectively. In the case of this example, the cooling fan 10 is fixed to the outer end of the rotating shaft 1 via a hub 19. Therefore, the cooling fan 10 rotates at the same angular velocity as the rotating shaft 1.

A driven pulley 6a, which is a transmission member, is provided between the bearing unit 4 and the hub 19 at a portion near the outer end of the intermediate portion of the rotary shaft 1. It is supported concentrically with the rotating shaft 1 via a fluid coupling 20 which is a coupling member. As the fluid coupling 20, various types of conventionally known structures can be used. For example, a plurality of driving-side circular plates each supporting an outer peripheral edge on an inner peripheral surface of an outer ring fixedly fitted on the driven pulley 6a side, and an outer peripheral surface of an inner ring fixedly fitted on the rotating shaft 1 side. A plurality of driven-side circular plates supporting the respective inner peripheral edges are alternately arranged in the axial direction of the rotating shaft 1, and a viscous fluid such as silicon oil is interposed between adjacent circular plates. Can be used.

As described above, the belt 7 is stretched between the driven pulley 6a provided around the rotary shaft 1 and the driving pulley fixed to the end of the crankshaft (not shown) to operate the engine. Sometimes, the rotating shaft 1 is freely rotatable. Also in the case of this example, a part of the rotating shaft 1
A mechanical seal 8 is provided between the impeller 5 and the bearing unit 4 so that cooling water flowing in the housing 3 does not enter the bearing unit 4 side.

In the case of this embodiment constructed as described above, when the driven pulley 6a rotates with the operation of the engine, it is transmitted to the rotary shaft 1 via the fluid coupling 20. And
The impeller 5 and the cooling fan 10 fixed to both the inner and outer ends of the rotating shaft rotate at the same angular velocity. The fluid coupling 20 transmits the rotation of the driven pulley 6a to the rotary shaft 1 with high transmission efficiency when the driven pulley 6a rotates at a low speed. Therefore, when the engine rotates at a low speed, the impeller 5 and the cooling fan 10
The driven pulley 6a rotates at a rotation speed close to that of the driven pulley 6a.

On the other hand, when the engine rotates at a high speed, the transmission efficiency of the fluid coupling 20 decreases, and only a part of the rotation of the driven pulley 6a is transmitted to the rotary shaft 1. Therefore, when the engine rotates at a high speed, the rotation speeds of the impeller 5 and the cooling fan 10 are
The rotation speed is much lower than the rotation speed of the driven pulley 6a.
For this reason, the impeller 5 constituting the water pump 2 does not rotate at an unnecessarily high speed, so that the power loss can be suppressed. In addition, the bearing unit 4 supporting the rotary shaft 1
Can also be improved in durability. Even in such a case, the rotational speed of the impeller 5 and the cooling fan 10 regulates the characteristics of the fluid coupling 20 so that the engine can be sufficiently cooled.

In the illustrated example, the driven pulleys 6a and 6b, which are transmission members, are provided between the rotary shaft 1 and the driven pulleys 6a and 6b are rotated with the rotation of the driven pulleys 6a and 6b.
The fluid coupling 20 is used as a coupling member for reducing the transmission efficiency from the shaft 6b to the rotary shaft 1. However, the coupling member may be any member that can reduce the transmission efficiency as the rotation increases, and various conventionally known devices can be used. For example, a structure in which an electromagnetic clutch, a torque limiter, or the like is incorporated and slips when the torque applied between the driven pulleys 6a, 6b and the rotating shaft 1 increases to reduce the transmission efficiency can be used. is there.

[0016]

The driving device for an engine cooling device according to the present invention is constructed and operates as described above. Therefore, the power loss of the engine is reduced while ensuring the performance of cooling the engine. In addition to improving the fuel efficiency of
The durability of the bearing supporting the rotating shaft can be improved.

[Brief description of the drawings]

FIG. 1 is a cross-sectional view illustrating an example of an embodiment of the present invention.

FIG. 2 is a sectional view showing an example of a conventional structure.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Rotating shaft 2 Water pump 3 Housing 4 Bearing unit 5 Impeller 6, 6a Followed pulley 7 Belt 8 Mechanical seal 9 Inner hub 10 Cooling fan 11 Rolling bearing 12 Fluid coupling 13 Shaft part 14 Outer hub 15 Rotor 16 Silicon oil 17 Bimetal 18 Labyrinth Part 19 Hub 20 Fluid coupling 21 Sleeve

Claims (1)

[Claims] 1. An impeller which constitutes a water pump for flowing cooling water through the engine based on the rotation of the rotating shaft by driving the rotation shaft via a transmission member by the engine, and In a driving device for an engine cooling device for rotating a cooling fan for blowing heat to a radiator for lowering the temperature by dissipating heat, a rotation of the transmission member is provided between the transmission member and the rotating shaft. A drive device for an engine cooling device, comprising: a joint member for reducing the transmission efficiency from the transmission member to the rotary shaft as it rises.