Dirt trap as a functional module in the impeller of a coolant pump

Abstract

A coolant pump (1) of an internal combustion engine, having a pump casing (2), in which a pump shaft (3) is rotatably supported by a water pump bearing assembly (4) and an impeller (6) connected in a rotationally fixed manner to the pump shaft (3) is associated with an intake space (7). During a rotation of the impeller (6) together with associated blades (8), a coolant as a working medium is pumped from the intake space (7), via a coolant outlet of the coolant pump (1), into a cooling system of the internal combustion engine. A dirt trap is associated as a functional module (12a) with the impeller (6) on a side facing away from the intake space (7), wherein the working medium flows into the functional module (12a) from the intake space via at least one opening (13) introduced into the impeller and emerges via a flow outlet (15a).

Claims

1. A coolant pump of an internal combustion engine, comprising: a pump casing, a pump shaft rotatably supported in the pump casing by a water pump bearing assembly, and an impeller connected in a rotationally fixed manner to the pump shaft, the impeller is associated with an intake space, wherein a rotation of the impeller, together with associated blades, pumps a coolant as a working medium in a fluid or volume flow from the intake space, via a coolant outlet of the coolant pump, into a cooling system of the internal combustion engine, wherein a functional module is attached to the impeller on a side of the impeller facing away from the intake space, the functional module including an enclosed space defined by a wall of the impeller blade and a connected portion of the functional module attached to the impeller blade wall, wherein the working medium flows into the enclosed space of the functional module from the intake space via at least one opening in the impeller blade wall and exits the enclosed space via a flow outlet formed in the connected portion.

2. The coolant pump as claimed in claim 1, wherein the functional module comprises a dirt trap of basket or screen construction.

3. The coolant pump as claimed in claim 1, wherein the opening and the flow outlet are close to the pump shaft.

4. The coolant pump as claimed in claim 1, wherein the functional module is integrated within an existing contour of the impeller.

5. The coolant pump as claimed in claim 4, wherein the enclosed space of the functional module is formed by a rotationally symmetrical recess formed in a front side of the impeller, said recess being closed by a perforated cover element or a screen disk as the connected portion.

6. The coolant pump as claimed in claim 1, wherein the connected portion is connected to the pump shaft and the impeller in an installed state.

7. The coolant pump as claimed in claim 6, wherein the connected portion has a pot shape with a cylindrical sleeve, which is sealed at the impeller and fixed in position, and a disk-type end wall, which is fixed on the pump shaft via a bushing.

8. The coolant pump as claimed in claim 1, wherein the separate functional module, which is produced from a metallic material or from a plastic, is fixed materially as a prefabricated component on the impeller.

9. The coolant pump as claimed in claim 1, wherein the flow outlet of the connected portion comprises a filter element, a mesh width of which defines a dirt particle size that can be removed from the cooling system.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

(1) Further features of the invention will emerge from the following description of the drawings, in which illustrative embodiments of the invention are shown. The embodiments illustrated show examples of solutions according to the invention, but these do not represent a definitive delimitation of the invention. In the drawings:

(2) FIG. 1 shows a section through a coolant pump having a functional module according to the invention;

(3) FIG. 2 shows a simplified detail of the coolant pump, the functional module of which is associated as a separate component with the impeller; and

(4) FIG. 3 shows a simplified detail of the coolant pump, the functional module of which is integrated into the impeller.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

(5) FIG. 1 shows a coolant pump 1 for a cooling circuit of an internal combustion engine (not shown) having a pump casing 2, in which a drivable pump shaft 3 is rotatably supported by a water pump bearing 4 embodied as a rolling bearing. The coolant pump 1 is driven, in particular, via a belt pulley 5 connected integrally to the pump shaft 3. An impeller 6 is secured in a rotationally fixed manner on one end of the pump shaft 3, said impeller having blades 8, which project into an intake space 7, and a front-side covering disk 9, which are connected to one another by axially aligned ribs 10 arranged in a circumferentially distributed manner. To seal off the water pump bearing 4 from the pump space or intake space 7, a mechanical seal 11 is provided as a seal. During the rotation of the impeller 6, coolant or fluid is pumped via an intake branch (not shown) of the pump casing 2 into the intake space 7 and, from there, into a discharge branch (not shown). On a side facing away from the intake space 7, the impeller 6 has associated with it a functional module 12a, which performs the function of a dirt trap, is supplied with a partial flow of the coolant and in which dirt particles in the coolant are separated out. The functional module 12a includes an enclosed space defined by a wall of the impeller blade 8 and a connected portion 12c of the functional module attached to the impeller blade wall. For this dirt trap purpose, circumferentially distributed openings 13 designed as bores are introduced into the impeller 6, close to the pump shaft 3. The coolant flowing through the opening 13 passes via a flow inlet 14 into the functional module 12a. Due to the rotation and based on a higher density, the dirt particles in the coolant move radially outward along an inner wall of the functional module 12a. The cleaned coolant passes via a flow outlet 15a of the functional module 12a into a pump space 21.

(6) FIGS. 2 and 3 show simplified detail views of the coolant pump 1. Through the enlarged illustrations, details, in particular, of the differently embodied functional modules 12a, 12b, each associated with the impeller 6, are made clearer. Here, the reference signs for components or parts which are the same or have the same function correspond to those in FIG. 1. The following descriptions are therefore restricted largely to differences in embodiment essential to the invention.

(7) FIG. 2 shows the enlarged functional module 12a according to FIG. 1, which is designed as a pot-shaped part. An end wall 16 of the functional module 12a, which is of disk-type configuration, forms a seal on the impeller 6 and is preferably secured materially thereon at the connected portion 12c of the functional module, connects an outer sleeve 17 to a bushing 18 fixed in position on the pump shaft 3. In this arrangement, the flow outlet 15a in the end wall 16 is designed as a filter with a screen-type structure and a defined mesh width.

(8) In FIG. 3, the impeller 6 is shown with the integrated functional module 12b attached to the impeller at a connected portion 12d. For this purpose, a rotationally symmetrical recess 19 forming a collecting space is introduced into the impeller 6 on the side facing away from the intake space 7. At the end, the recess 19 is closed by a cover element 20 embodied as a filter with a defined mesh width.

LIST OF REFERENCE SIGNS

(9) 1 coolant pump 2 pump casing 3 pump shaft 4 water pump bearing 5 belt pulley 6 impeller 7 intake space 8 blade 9 covering disk 10 rib 11 mechanical seal 12a, 12b functional module 12c, 12d connected portion 13 opening 14 flow inlet 15a, 15b flow outlet 16 end wall 17 sleeve 18 bushing 19 recess 20 cover element 21 pump space