JPS6131140Y2 - - Google Patents

Description

[Detailed description of the invention] The present invention aims to improve internal combustion engines, particularly in devices that drive a cooling water pump attached to the engine via a gear linked to a crankshaft or the like. This invention relates to a configuration of a drive device that is designed to shorten and lighten the pump shaft and reduce the installation space for the cooling water pump by changing the shape and arrangement of the pump shaft.

Among internal combustion engines such as diesel engines,
In so-called water-cooled engines, cooling water passages are formed in parts exposed to high temperatures such as the cylinder block and cylinder head, and the engine is prevented from overheating by flowing cooling water through the passages. A cooling water pump such as a seawater pump that forcibly circulates seawater in the cooling water system, or a seawater pump that supplies secondary seawater cooling water to a freshwater cooler installed in the freshwater cooling system, is installed to cool the cooling water. The pump is gear-linked to an output shaft such as a crankshaft.

By the way, as a conventional engine-attached cooling water pump drive device of this kind, for example, as shown in FIG.
A pump shaft bearing case 6, which holds the bearings 4 and 5 of the pump shaft 3, is fixed to the rear surface 2 of the gear case 1 attached to the front side of the engine with bolts 7, and a rotating rubber type is attached to the rear of the pump shaft bearing case 6. At the same time as attaching the casing 9 of the cooling water pump 8, the impeller 10 of the pump 8 is fixed to one end 3a of the pump shaft 3, and furthermore, the impeller 10 of the pump 8 is attached to the part where the pump shaft 3 penetrates inside the gear case 1, and is interlocked with a crankshaft (not shown). gear 11
The key 13 and the fixing nut 14 connect the pump drive gear 12 that meshes with the key 13 and applies rotational force to the pump shaft 3.
By fixing the bolts 7 together using
The structure is such that the cooling water pump body can be easily removed by simply loosening the pump body, and in particular, the front projecting end 3b of the pump shaft 3 is used to drive equipment such as a generator, which is another driven element. Pulley 15
When fixing, a third bearing member 16 is provided at a position in front of the drive gear attachment part of the pump shaft 3, and the third bearing member 16 is attached to a bearing support member 18 provided on the gear case lid 17 that covers the front surface of the gear case 1. By supporting the pump shaft 3, the bending strength of the pump shaft 3 is ensured.

However, in the pump drive device having such a conventional configuration, the bearings 4 and 5 supporting the pump shaft 3 are
It is necessary to make the interval l ₁ as large as possible in order to ensure smooth rotation of the pump shaft 3, and the drive gear 12 is located within the gear case 1,
Because it has to mesh with the gear 11, the cooling water pump 8 protrudes rearward by a length _L1 from the rear surface 2 of the gear case 1, and occupies a large installation space, especially in small engines. Not only is there a problem that the parts mounting position is restricted, but in addition to the pump drive mechanism, when the pulley 15 is attached to the pump shaft end 3b, the pump shaft 3 itself becomes long, and a bearing for reinforcing the pump shaft is required. There is a problem in that parts such as the member 16 and the bearing support member 18 are required, leading to a rise in engine manufacturing costs.

The present invention focused on the problems that such conventional cooling water pump drive devices had, and was created with the aim of making the drive device more compact and reducing the number of parts by changing the mounting structure of the drive gear. A cooling water pump drive for an internal combustion engine, in which a pump shaft bearing case is formed separately from a gear case, and the pump shaft is rotatably supported by two or more bearing members provided in the pump shaft bearing case. In the apparatus, the pump shaft bearing case includes the two or more bearing members and a pump shaft supported between the bearing members, and is fitted in a gear case, and the pump shaft bearing case includes the two or more bearing members and a pump shaft supported between the bearing members. It is characterized by a configuration in which a drive gear is attached to the.

Hereinafter, the present invention will be described in detail with reference to embodiments shown in the accompanying drawings.

Here, Fig. 2 is a front cross-sectional view of an engine to which the pump drive device of the present invention is applied, Fig. 3 is a cross-sectional view taken along the - line in Fig. 2, and Fig. 4 is an enlarged cross-section of the main part of the drive device of the present invention The figure and FIG. 5 are cross sections taken along the - line in FIG. 4.

In each of these figures, the gear case 21 attached to the front of the cylinder block 22 of the engine is
An intermediate gear 25 that meshes with a crank gear 24 provided at the end of the crankshaft 23 inside thereof, a fuel pump drive gear 26 and a camshaft gear 27 that mesh with the intermediate gear 25, and a fresh water pump that meshes with the camshaft gear 27. A drive gear 28 and a pump drive gear 29, which is one of the essential parts of the present invention, are housed therein, and below the crank gear 24 there is provided a drive gear 28 and a pump drive gear 29, which is one of the essential parts of the present invention. A lubricating oil pump drive gear 31 is in mesh with an intermediate gear 32 .

The gear case 21 housing the gear drive device with the above structure has its front surface covered by a gear case lid 33, and a pump shaft bearing case 34, which is a main part of the present invention, at the mounting part of the pump drive gear 29. It holds the mating.

That is, the pump shaft bearing case 34 is attached to the rear wall 21 of the gear case 21, as shown in FIGS. 3 and 4.
The front end is inserted into the mounting hole 35 provided in the gear case lid 33 through a packing 36, and the front end is inserted into the support hole 38 provided in the gear case lid 33 with a packing 39 interposed therebetween. bolt 37
It is fixed integrally with the gear case 21 by tightening with. In addition, the pump shaft bearing case 34
holds two bearing bearing members 41 and 42 in its center hole 40, and the bearing member 4
1 and 42 rotatably support the pump shaft 43, and the bearing member 4 of the pump shaft 43
The cooling water pump drive gear 29 is spline-fitted to a spline portion 44 formed in the middle of the portions supported by 1 and 42.

Note that the bearing case 34 penetrates inside the gear case 21 and a part of the wall 45 surrounding the outer periphery of the drive gear 29 is used for inserting the drive gear 29 between the bearings 41 and 42 and for inserting the drive gear 29 between the bearings 41 and 42. It has a large opening as a window 46 for supplying lubricating oil.

In the figure, reference numeral 47 denotes a casing of a cooling water pump 49 that is disposed on the rear side of the pump bearing case 34 and fixed with bolts 48, and inside the pump casing 47 is an end portion of the pump shaft 43. A rubber impeller 50 fixed to 43a is housed. Further, on the front end 43b side of the pump shaft 43, the bearing 42, the drive gear 29, and the bearing 4 are provided.
A spacer 52 is fitted with an O-ring 51 fitted to the inner periphery of the pump shaft 43, and is fixed by a locking nut 53. A drive pulley 54 is fixed to the front end side with a nut 55.

In addition, in the figure, 56 and 57 are oil seals, and 58
1 and 2 respectively show mechanical seals provided in the cooling water pump 49.

The cooling water pump drive device of the present invention has the above configuration. When assembling this into an engine, the drive gear 29 is inserted through the window 46 of the pump shaft bearing case 34, and the pump shaft 43 is mounted on the bearing case. 4
The two drive gears 29 and bearings 41 are fitted in the center hole in the axial direction, rotatably supporting the pump shaft 43, each part is provided with an oil seal, etc., and cooling water is provided at the rear of the pump shaft bearing case 34. pump 49
After installing the cooling water pump 49 and performing a performance test of the cooling water pump 49, the bearing case 34 is fitted into the mounting holes 35 and 38 of the gear case 21 and the gear case lid 33,
The drive pulley 54 may be fixed to the front end of the pump shaft 43 by fixing with bolts 37. On the other hand, when the drive gear 29 meshes with another camshaft gear 27 at the portion exposed from the window 46 during engine operation and rotates the pump shaft 43 under the rotational force of the crankshaft 23, the pump The impeller 50 of the cooling water pump 49 provided on the shaft 43 rotates and supplies cooling water to each cooling section, and the lubricating oil droplets scattered inside the gear case 21 enter the bearing case 34 through the window 46 and damage the bearings. 41 and 42 are lubricated to allow the pump shaft 43 to rotate smoothly.

As described above, in the cooling water pump drive device of the present invention, the bearing holding part of the pump shaft bearing case, which is formed separately from the gear case, is fitted into the gear case, and the drive gear is connected between the bearings provided in the pump shaft bearing case. By providing a It is shorter and lighter, and the installation space for the cooling water pump is greatly reduced compared to conventional ones, which is extremely convenient for promoting downsizing of the engine.In addition, a drive pulley is attached to the front end of the pump shaft. Even in this case, there is no need to install reinforcing bearings, and the number of parts can be reduced, which has the effect of suppressing a rise in engine manufacturing costs.

Moreover, with the device of the present invention, the bearing case, drive gear, and cooling water pump can be removed from the gear case all at once, making it possible to check the pump performance and quality before assembly, and making it easy to repair and maintain the cooling water pump. You can also expect the effect of

[Brief explanation of drawings]

FIG. 1 is a schematic sectional view showing an example of the configuration of a conventional cooling water pump drive device, FIG. 2 is a front sectional view of an engine to which the cooling water pump drive device of the present invention is applied, and FIG.
The figure is a cross-sectional view taken along the - line in FIG. 2.
Further, FIG. 4 is an enlarged sectional view of a main part of the drive device of the present invention, and FIG. 5 is a sectional view taken along the - line arrow in FIG. 21... Gear case, 29... Drive gear, 34
... Pump shaft bearing case, 41, 42 ... Bearing member, 43 ... Pump shaft, 49 ... Cooling water pump.

Claims (1)

[Scope of utility model registration request] A cooling water pump drive device for an internal combustion engine, in which a pump shaft bearing case is formed separately from a gear case, and the pump shaft is rotatably supported by two or more bearing members provided in the pump shaft bearing case. The pump shaft bearing case includes the two or more bearing members and a pump shaft supported between the bearing members, and is fitted in a gear case, and the pump shaft between the bearing members includes a A cooling water pump drive device, characterized in that a drive gear is attached.