WO1994019588A1

WO1994019588A1 - Water pump driving structure for an internal combustion engine

Info

Publication number: WO1994019588A1
Application number: PCT/JP1994/000248
Authority: WO
Inventors: Hidetada Fukushima
Original assignee: Kabushiki Kaisha Komatsu Seisakusho
Priority date: 1993-02-22
Filing date: 1994-02-18
Publication date: 1994-09-01

Abstract

A water pump driving structure for an internal combustion engine which can provide a performance satisfying requirements such as high cooling capability and low noise by driving a water pump and a cooling fan at desired rotating speeds and in desired rotating directions and can be set at different rotating speeds without major modifications to the construction, thereby making it possible to use installation space effectively, said water pump driving structure being characterized in that it comprises a water pump pulley (7) and a fan pulley (12) driven by a crank pulley, that an impeller driving shaft (6) of said water pump (1) is secured to said water pump pulley (7), that said cooling fan (13) is secured to said fan pulley (12), that said fan pulley (12) is mounted on said impeller driving shaft (6) in such a manner as to idle thereon, and that the diameter of said water pump pulley (7) for driving said water pump (1) and the diameter of said fan pulley (12) for driving said cooling fan (13) are, respectively, independently set.

Description

Description Water pump drive structure for internal combustion engine

The present invention relates to a water pump drive structure for a water-cooled internal combustion engine. Background technology

Conventionally, in many relatively small engines mounted on automobiles, etc., the water pump drive structure has a simple, low-cost structure with the water pump and cooling fan installed coaxially. .

Fig. 4 shows a partial cross-sectional side view of a conventional general internal combustion engine in which a water pump and a cooling fan are installed coaxially. A water pump pulley 16 is attached to the tip of the impeller drive shaft of the water pump 1, and a cooling fan 13 is attached to the water pump pulley 16 via an adapter 17. The water pump bouly 16 is driven via a V-belt 14 by a crank pulley 19 attached to the end of a crank shaft 18 to drive the water pump 1 and the cooling fan 13 at the same rotational speed. It is driving.

However, such a conventional water pump drive structure has the following problems.

(1) Usually, the diameter of the cooling fan 13 is much larger than the diameter of the impeller (not shown) of the water pump 1. Therefore, when the diameter of the water pump pulley 16 and the diameter of the crank pulley 19 are set so that the rotation speed of the cooling fan 13 can reach the rotation speed that reaches the maximum permissible peripheral speed of the cooling fan 13 However, the rotation speed of the water pump 1, which is driven coaxially and at the same rotation speed, is usually relatively lower than the allowable rotation speed of the water pump 1, and the performance of the water pump 1 can be maximized. Can not. Also, in order to secure the required flow rate of cooling water, a large water pump 1 must be installed, and as a result, a large and costly water pump 1 is required, and the weight and mounting space are increased. Problems such as an increase in (2) In recent years, large, low-speed rotating fans have been adopted in order to reduce the noise of the cooling fan 13. However, the large-sized cooling fan 1

If 3 is installed, the rotation speed of water pump 1 will be even lower. This leads to a further increase in the size of the water pump 1, which requires a large mounting space for the water pump 1 and a more expensive structure. Disclosure of the invention

SUMMARY OF THE INVENTION The present invention has been made to solve the above-mentioned drawbacks of the prior art, and has been made without changing the relative positions of the water pump and the cooling fan and without significantly changing the structure. It is an object of the present invention to provide a water pump drive structure of an internal combustion engine that can drive a fan at a desired rotation speed and a desired rotation direction. A water pump drive structure for an internal combustion engine according to the present invention includes a water pump pulley and a fan pulley driven from a crank pulley via a belt, and an impeller drive shaft that drives an impeller of the water pump on the water pump bully. In addition to fixing the fan, the cooling fan is fixed to the fan wheel, and the fan pulley is attached to the impeller drive shaft so as to freely rotate. Also, the diameter of the water pump pulley that drives the water pump and the diameter of the fan pulley that drives the cooling fan are set independently. In addition, the crank burley is a crank pulley in which the diameter of the mounting portion of the belt that drives the water pump pulley and the diameter of the mounting portion of the belt that drives the fan pulley are independently set. In addition, the rotation direction of the water pump pulley that drives the water pump and the rotation direction of the family that drives the cooling fan are set independently. With this configuration, the water pump pulley and the fan pulley have a coaxial structure and can rotate freely with each other, so that the water pump pulley and the fan pulley can be rotated at different rotation speeds. Therefore, by setting the diameters of the water pump pulley and the fan pulley independently of each other, it is possible to achieve a rotation speed corresponding to the performance required for the water pump and the cooling fan. In addition, since the diameter of the belt mounting part of the crank pulley can be set to a different diameter, the water pump pulley and the pump This is effective when the required performance cannot be met with only one diameter. From the above, for example, it is possible to increase the cooling performance by rotating the water pump at a high speed, and to reduce the noise caused by the cooling fan by rotating the cooling fan at a low speed. In addition, it is possible to set the number of rotations to meet the required performance without changing the relative positions of the water pump and cooling fan, and it is not necessary to make a major structural change such as using a large water pump. Effective use of space, suppression of weight increase, suppression of cost increase, etc. will be possible. Furthermore, despite the coaxial structure, it is possible to rotate in the opposite direction to the direction of rotation of the water pump bully and fan pulley. For example, by simply changing the way the fan pulley is attached to the belt, the cooling fan The direction of rotation is changed, and a suction system or a blowing system, which is a cooling system for an internal combustion engine such as an engine, can be selected as necessary. BRIEF DESCRIPTION OF THE FIGURES

FIG. 1 is a cross-sectional view of a main part of a water pump drive structure for an internal combustion engine according to the present invention, FIG. 2 is an explanatory view of how to attach a belt of a water pump pulley of an application example according to the present invention, and FIG. FIG. 4 is an explanatory view of how to attach a belt of a fan pulley of an application example according to the present invention. FIG. 4 is a side view of a partial cross section of a water pump driving structure of an internal combustion engine in which a water pump and a cooling fan according to the related art are coaxially installed. It is. BEST MODE FOR CARRYING OUT THE INVENTION

Preferred embodiments of the water pump driving structure for an internal combustion engine according to the present invention will be described in detail below with reference to the accompanying drawings.

FIG. 1 is a sectional view showing a water pump driving structure of an internal combustion engine located coaxially with a cooling fan. In the figure, outer rings 3b and 4b of bearings 3 and 4 are press-fitted into stepped holes provided in housing 2 of water pump 1, and impellers are inserted into inner rings 3a and 4a of bearings 3 and 4. A drive shaft 6 is fitted into the drive shaft 6, and the impeller drive shaft 6 is rotatable with respect to the housing 2. In addition, the impeller drive shaft 6 has a water pump 1 at one end. At the same time as the impeller 5 is fixed, a water pump bully 7 is press-fitted and fixed in front of the bearing 3, and an adapter 10 is mounted in front of the water pump pulley 7 via the bearings 8 and 9. Has been attached. These bearings 8 and 9 are composed of inner rings 8a and 9a and outer rings 8b and 9b, respectively, and the impeller drive shaft 6 and the adapter 10 can rotate freely with each other. A fan pulley 12 and a cooling fan 13 are fastened to the adapter 10 by bolts 11. Further, a V-belt 14 and a V-belt 15 for driving are attached to the water pump pulley 7 and the fan pulley 12, respectively. Although the diameters of the fan pulleys 12 and the water pump pulley 7 can be set arbitrarily, in this embodiment, the diameter of the fan pulleys 12 is set to be larger than the diameter of the water pump pulley 7. I have. Here, the V-belt may be a general V-belt or a poly-V-belt (P01y—VeeBelt) to which a belt used in an internal combustion engine is applicable. In addition, if necessary, a commonly used belt other than the V belt may be used.

The operation of the water pump drive structure for an internal combustion engine having such a configuration is performed as follows. The water pump pulley 7 is driven by a crank pulley (not shown) via a V-belt 14, so that the impeller 5 fixed to the impeller drive shaft 6 is the same as the water pump pulley 7. Driven at rotational speed. At the same time, the fan pulley 12 is also driven and rotated by the crank pulley (not shown) via the V-belt 15, but the diameter of the fan pulley 12 is set to be larger than the diameter of the water pump pulley 7. I have. Therefore, since the rotation speed is inversely proportional to the diameter, the rotation speed of the cooling fan 13 is smaller than the rotation speed of the impeller 5. That is, it is possible to obtain the maximum performance of the water pump 1 by setting the impeller 5 to high-speed rotation, for example, the allowable rotation speed of the water pump 1. On the other hand, noise can be reduced by setting the cooling fan 13 to low-speed rotation.

As described above, by independently setting the diameters of the water pump bully 7 and the fan pulley 12, even if the water pump 1 and the cooling fan 13 are installed coaxially, the water pump 1 Drive impeller 5 and cooling fan 13 at desired rotational speeds respectively. Can be Therefore, it is possible to effectively use the small and low-priced water pump 1 and the large-diameter and low-noise cooling fan 13. In the bearings 8 and 9 fitted into the adapter 10, the inner rings 8 a and 9 a rotate at the same rotation speed as the water pump pulley 7, and the outer rings 8 b and 9 b rotate at the same rotation speed as the fan pulley 12. Rotate with. Therefore, when the water pump pulley 7 and the fan pulley 12 rotate in the same direction, the relative rotation speed between the inner rings 8a, 9a and the outer rings 8b, 9b5 becomes Since the rotation speed is different from that of 2, the relative rotation speed is small, the damage due to wear and the like is small, and the service life of the bearings 8 and 9 is significantly prolonged.

Furthermore, since the diameters of the water pump pulley 7 and the fan pulley 12 can be set independently, even if the water pump 1 and the cooling fan 13 are the same part, they have different capacities, for example, When the cooling capacity of the water pump 1 is small and the cooling capacity of the cooling fan 13 is required to be large, the diameter of the water pump bully 7 should be relatively large, and the diameter of the fan pulleys 12 should be relatively large. The requirement is achieved by reducing the value to a small value, that is, by adjusting the rotation ratio. Moreover, there is no need to significantly change the water pump drive structure, and the invention can be applied to a limited installation space.

In addition, regarding the diameter of the crank pulley to which the V belts 14 and 15 for driving the water pump burries 7 and the fan pulleys 12 are respectively set, the mounting diameters of the V belts 14 and 15 are set respectively. However, even if the diameter is different, the same operation and effect as described above can be obtained. In addition, the diameters of the water pump pulley 7 and the fan pulley 12 and the diameter of the portion to be attached to the crank pulley are set in combination. It is also possible to make 13 a lower speed rotation.

Next, application examples of the present embodiment will be described with reference to FIGS. This application example is a case where the rotation direction of the cooling fan is reversed in the above embodiment. In Fig. 2 showing the water pump pulley side, a V-belt 14 for driving is attached to the crank pulley 19, the tension pulley 21 and the water pump pulley 7, and the arrow 23 Driven in the direction. The tension pulley 21 is a general pulley (not shown). It is movable in the direction 22 by a simple tension adjusting device, and the V belt 14 is adjusted to a predetermined tension. On the other hand, in Fig. 3 showing the fan pulley side, a driving V-belt 15 is attached to the crank pulley 19, idler pulley 28, fan pulley 12, tension pulley 21 and idler pulley 26. Driven in the direction of arrow 27 by 1 9. The movement of the tension pulley 21 in the direction 25 adjusts the V-belt 15 to a predetermined tension. The V belt 15 is preferably a belt that can be driven on both sides, such as a poly V belt.

With this configuration, the water pump pulley 7 and the fan pulley 12 rotate in opposite directions. Accordingly, referring to FIG. 1, the impeller 5 of the water pump 1 rotates in the same direction as in the above embodiment, but the cooling fan 13 rotates in the opposite direction to that of the above embodiment. In other words, by simply changing the way the V-belt 15 and other belts are attached, it is possible to select the cooling method for the engine, such as the suction method or the blowing method, so that the cooling required for the water pump 1 and cooling fan 13 is required. It is easy to respond to performance such as performance and noise level, and can meet various required specifications with few types of parts. Industrial applicability

According to the present invention, by driving the water pump and the cooling fan at desired rotational speeds and rotational directions, performances corresponding to demands such as high cooling performance and low noise can be obtained, and further, significant structural changes are made. Since it can be set to different rotation speeds without the need to perform this, it is useful as a water pump drive structure for an internal combustion engine that enables effective use of installation space.

Claims

The scope of the claims

1. A cooling fan is installed coaxially with the water pump, and in a water pump driving structure of an internal combustion engine that drives the water pump and the cooling fan by a bury driven from a crank pulley via a belt, The pulley includes a water pump pulley and a fan pulley, and an impeller drive shaft of the water pump is fixed to the water pump pulley, and the cooling fan is fixed to the fabry, and the pump is fixed to the water pump pulley. A water pump drive for an internal combustion engine, characterized in that one wheel is freely rotatably mounted on the impeller drive shaft.

2. The diameter of the water pump pulley that drives the water pump and the diameter of the fan pulley that drives the cooling fan are set independently of each other. Water pump drive structure of internal combustion engine.

3. The crank pulley is a crank pulley in which a diameter of a mounting portion of a belt for driving the water pump pulley and a diameter of a mounting portion of a belt for driving the pump are independently set. 3. The water pump drive structure for an internal combustion engine according to claim 1 or 2, wherein:

4. The rotation direction of the water pump pulley that drives the water pump and the rotation direction of the fan pulley that drives the cooling fan are set independently of each other. A water pump drive structure for an internal combustion engine according to claim 1.

5. The crank pulley is a crank pulley in which a diameter of a mounting portion of a belt for driving the water pump pulley and a diameter of a mounting portion of a belt for driving the fan pulley are independently set. 5. The water pump drive structure for an internal combustion engine according to claim 4, wherein: