Cooling Water Pump, Preferably Of Motor Car Engines

Abstract

Cooling water pump, preferably for vehicle engines comprising a housing portion, bearing, drive portion, impeller wheel and sealing means and possibly a fan wheel in connection to the pump device, characterized in that pump device is shaftless and that the parts in the pump device are united to an undetachable unit.

Description

The present invention relates to a fluid pump, preferably a cooling water pump, for a motor car engine. The pump in accordance with the invention constitutes in mounted condition a shaftless unit in which the components are undetachably united together.

The conventional cooling water pumps are so designed, that they consist of relatively large parts fastened together with screws and such pumps are relatively heavy and space consuming.

The advantages of the fluid pump in accordance with the present invention are the following.

It is possible to select various materials for this shaftless type of pump. Suitable materials might be aluminum, plastics or pressed metal sheet. In selecting a suitable material, the pump will be cheap and light and has in relationship to the small weight a good structural strength. The good reliability in operation is depending on the fact that there will be smaller unbalance and smaller masses in the pump components. Another advantage is that since there is no conventional shaft, a bearing is selected with greater pitch diameter than earlier. Such a bearing, preferably of single row deep groove type, is simpler and axially more compact. A further advantage is the possibility of getting a very good sealing effect since the sealing diameter is very small. The pump is so designed that a good ventilating and drying of the bearing is obtained in front of the same, so that fluid particles will not get into contact with the bearing. It is avoided that iron oxide is created in the bearing which grinds clearance in the bearing, which in its turn gives rise to warpings in the seal and therewith deteriorated sealing effect. Regarding an outer-ring-rotated bearing, it is possible to place the seal with its small diameter essentially in the radial center line of the bearing, whereby an absolutely effective sealing is obtained.

The invention will now be described with reference to the accompanying drawings in which:

FIG. 1 shows an embodiment of the pump with an especially shaped inner-ring-rotated bearing; and

FIG. 2 shows a modification of the pump with an outer-ring-rotated bearing.

A pump unit in accordance with the invention consists of the following main components: housing 1, bearing 2, drive portion 3, rotor 4 and sealing element 5.

FIG. 1 shows a cooling water pump in which the housing portion 1 consists of a relatively thin wall 6 of pressed sheet metal, die-casted aluminum or plastics which is fixed to a stronger housing portion 7 suitably of aluminum. In said portion 7 the outer ring 8 of the bearing 2 is fitted by shrinkage fit or otherwise. The inner raceway 9 is in the embodiment shown integrated with the drive portion 3 of the pump, but the raceway might also be shaped in a separate inner ring fitted on the drive portion 3. In the embodiment shown, the rolling bodies of the bearing consist of balls. The bearing is provided with a cage 10 of suitable type. As shown from the figure, the inner ring will be rotated. The pump is in this case driven by a belt from a suitable source of power. For this purpose the part 11 of the drive portion is profiled on its outer surface as shown at 12. The drive portion is at its part turned toward the bearing shaped with a part 13 with small diameter. The rotor 4 is fixed to this part by, for instance, welding, riveting or in another way. In the space shaped outside the part 13 between the wall 6 of the housing portion and the drive portion, a space is formed in which it is suitable to place the seal 5 which seals against fluid from the rotor side.

In the housing portion there is a number of large openings 14 intended for ventilating, drying and draining purposes. Through these openings there is obtained a very effective ventilating or draining in front of the bearing. Close to the drive side of the pump there can be applied a fan not shown here. This can be designed in such a way that the fan is integrated with the drive portion of the pump and so that a combined fan and drive portion is obtained. The fan can, of course, be a separate part fixed to the drive portion.

In FIG. 2 a modification of the cooling water pump is shown in which, contrary to the above mentioned embodiment, the outer ring of the bearing rotates. In this example a conventional bearing is used, for example a single row deep groove ball bearing, the inner ring 15 of which is fitted on an annular part 16 of the housing portion 1. The outer ring 17 of the bearing is fitted into a bearing seat 18 in the drive portion 3. The outer surface of the drive portion is profiled at 19 as in the first example. The drive portion is provided with a web portion 20 which is fixed to a portion 21 of the rotor by, for example, welding. The seal 5 is fitted to a suitable place on the portion 21 in connection with the inner part of the housing portion 1. The seal can also be located in the radial center line of the bearing whereby angular warpings are eliminated. The drive portion is also in this embodiment provided with large draining/ventilating openings 22.

Claims

I claim:

1. A replaceable and/or disposable pump unit for liquid-cooled internal combustion engines preferably for vehicle engines and adapted to be mounted in an opening of the pump housing, said pump unit including a pump unit housing, an impeller, a drive member operatively connected to the impeller as an integral structure to rotate the same and forming therewith a rotatable assembly, bearing means supporting the drive member for rotation relative to the unit housing and a seal adapted to seal an annular space between the rotatable assembly and unit housing, said pump unit housing, impeller, drive member, bearing means and seal forming an integral undetachable shaftless unit and said bearing means having a comparatively large pitch diameter.

2. Pump in accordance with claim 1, characterized in that the drive member has a portion forming the inner member of the bearing and is rotatable therewith.

3. Pump in accordance with claim 1, characterized in that the drive member has a portion forming the outer member of the bearing that rotates therewith.

4. Pump in accordance with claim 1, characterized in that the drive member has a portion fixed to surrounding an outer element of the bearing.

5. Pump in accordance with claim 1, characterized in that a number of large ventilating or draining openings are arranged close to said bearing so that ventilation/drainage of said bearing is obtained.

6. Pump in accordance with claim 1, characterized in that the seal in the pump unit is of small diameter and positioned close to the bearing.

7. Pump in accordance with claim 1 characterized in that the seal is of smaller diameter than the bearing and that its center line in axial direction essentially coincides with the center line of the bearing.

8. Pump in accordance with claim 1, characterized in that at the drive side of the pump there is arranged a fan wheel integrated with the drive portion.

9. Pump in accordance with claim 1, characterized in that the fan wheel consists of a separate part-unit fixed to the drive portion.