GB2357377A

GB2357377A - Cooling a combined pump and electric generator

Info

Publication number: GB2357377A
Application number: GB9929232A
Authority: GB
Inventors: Marc J Thevenin; Gerard J Kneppers
Original assignee: Delphi Technologies Inc
Current assignee: Delphi Technologies Inc
Priority date: 1999-12-13
Filing date: 1999-12-13
Publication date: 2001-06-20
Also published as: GB9929232D0

Abstract

A combined pump and electric generator comprising a pump housing (30) having a main fluid passage (32) with a fluid inlet (34) and a fluid outlet (36); a generator housing (46) secured to the pump housing; a shaft (18) extending through the pump housing, through the main fluid passage in the pump housing, and through the generator housing, and having a longitudinal axis (A); a rotor winding (56) secured to the shaft inside the generator housing; an annular stator winding (58) secured inside the generator housing around the rotor winding; pump vanes (40) secured to the shaft inside the main fluid passage; drive means (20) secured to one end (22) of the shaft outside of the pump housing and the generator housing for rotating the shaft about the longitudinal axis; a coolant bore (60) extending substantially longitudinally through the shaft; and a second fluid passage (64) fluidly connecting the coolant bore in the shaft with the main fluid passage in the pump housing. Provides internal cooling for the rotor winding.

Description

2357377 COMBINED PUMP AND ELECTRIC GENERATOR

Technical Field

The present invention relates to a combined pump and electric generator for mounting on an engine, and in particular for mounting on an engine of a motor vehicle.

13ackjzround of the Invention It is known to provide an electric generator in a motor vehicle.

The generator is mounted on the engine of the motor vehicle and has a rotor which is rotated by a pulley driven by the engine. Fluid channels may be provided in the housing of the generator for the flow of coolant fluid. It is also known to provide a pump which is mounted on the engine of the motor vehicle. The pump has a pulley driven by the engine to pump coolant fluid through the coolant passages in the block of the engine.

Summary of the Invention

It is an object of the present invention to provide an arrangement where the pump and the electric generator are integrated as a single unit.

A combined pump and electric generator in accordance with the present invention comprises a pump housing having a main fluid passage with a fluid inlet and a fluid outlet; a generator housing secured to the pump housing; a shaft extending through the pump housing, through the main fluid passage in the pump housing, and through the generator housing, and having a longitudinal axis; a rotor winding secured to the shaft inside the generator housing; an annular stator winding secured inside the generator housing around the rotor winding; pump vanes secured to the shaft inside the main fluid passage; drive means secured to one end of the shaft outside of the pump housing and the generator housing for rotating the shaft about the longitudinal axis; a coolant bore extending substantially longitudinally through the shaft; 2 and a second fluid passage fluidly connecting the coolant bore in the shaft with the main fluid passage in the pump housing.

The present invention provides an arrangement for integrally combining a pump and an electric generator, in which the rotor winding can be cooled internally by the pumping of fluid through the coolant bore in the shaft.

Brief Description of the Drawings

The present invention will now be described, by way of example, with reference to the accompanying drawings, in which:- Figure 1 is a cross-sectional view of a combined pump and electric generator in accordance with the present invention.

Description of the Preferred Embodiment

Referring to the drawing, the combined pump and electric generator 10 in accordance with the present invention is for mounting on an engine 12. The engine 12 has a block 14 with a coolant fluid passage 16 therein. The combined pump and electric generator 10 has a shaft 18 which is rotatable about its longitudinal axis A. A pulley 20 is attached to one end 22 of the shaft 18, the pulley being driven by the engine 12 to rotate the shaft about the axis A. The other end 24 of the shaft 18 is rotatably mounted in a sealed aperture 26 in the engine block 14.

The pump 28 of the combined pump and electric generator 10 includes a pump housing 30 having a main fluid passage 32 therethrough. The main fluid passage 32 has a fluid inlet 34 and a fluid outlet 36. The shaft 18 extends through a bore 38 in the pump housing 30. The bore 38 passes through the main fluid passage 32, and pump vanes 40 are secured to the shaft 18 and extend into the main fluid passage. The shaft 18 is rotatably mounted in a bearing 42 secured in the bore 38 adjacent the one end 22 of the shaft.

Rotation of the shaft 18 and the pump vanes 40 pumps coolant fluid from the fluid inlet 34 through the main fluid passage 32 to the fluid outlet 36. The 3 fluid inlet 34 and fluid outlet 36 are connected to the coolant system for the engine 12.

The electric generator 44 of the combined pump and electric generator 10 includes a generator housing 46 having a fluid channel 48 therein. The generator housing 46 is secured to the pump housing 30. A first end 50 of the fluid channel 48 opens into the main fluid passage 32 in the pump housing 30. The second end 52 of the fluid channel 48 either opens into the coolant fluid passage 16 in the engine block 14 as shown, or opens into the main fluid passage 32 in the pump housing 30. Where the second end 52 opens into the coolant fluid passage 16, the first end 50 is preferably located downstream of the pump vanes 40. Where the second end opens into the main fluid passage 32, the first and second ends are positioned on either side of the pump vanes 40.

The shaft 18 extends through the generator housing 46 and is rotatably mounted in a bearing 54 secured in the generator housing 46 adjacent the other end 24 of the shaft. A rotor winding 56 is secured on the shaft 18 inside the generator housing 46. An annular stator winding 58 is mounted inside the generator housing 46 around the rotor winding 56. Rotation of the shaft 18 causes the rotor winding 56 to rotate about axis A relative to the stator winding 58 to generator electrical power.

As can be seen in the drawing, the shaft 18 extends through both the pump housing 30 and the generator housing 46 with the pulley mounted on the one end 22 of the shaft adjacent the pump housing, and the other end 24 being adjacent the generator housing. The shaft 18 has a coolant bore 60 which extends longitudinally along axis A for most of its length and which opens at the other end 24 of the shaft into the coolant fluid passage 16 in the eng ine block 14. Adjacent the one end 22 of the shaft 18, the coolant bore 60 extends in a radial direction and opens into a sealed annular channel 62 in the bore 38 in the pump housing 30. The annular channel 62 is defined by a pair of seals 66 positioned in the bore 38, and is positioned between the bearing 42 and the pulley 20. The annular channel 62 is fluidly connected 4 with the main fluid passage 32 by a second fluid passage 64 formed in the pump housing 30. The second fluid passage 64 preferably opens into the main fluid passage 32 downstream of the pump vanes 40. On rotation of the pump vanes 40, coolant fluid is pumped from the main fluid passage 32, through the second fluid passage 64 and annular channel 62, through the coolant bore 60 in the shaft 18, and into the coolant fluid passage 16 in the engine block 14.

The seals 66 in the bore 38, and additional seals 68 in the bore, substantially prevent coolant fluid leaking from the pump housing 30, reaching the bearing 42, and leaking into the generator housing 46.

The present invention provides a combined pump and electric generator 10 in which a common shaft 18 and a common pulley 22 is used for both the pump 28 and the electric generator 44. Further, the shaft 18 has a coolant bore through which coolant fluid can be pumped by the pump 28 to provide internal cooling for the rotor winding 56 of the electric generator 44.

In an alternative arrangement to the above described embodiment, the other end 24 of the shaft 18 may be separated from the engine block 14. In this case, or as a further alternative to the above described embodiment, an additional fluid passage (not shown) may be provided between the coolant bore 60 at the other end 24 of the shaft 18 and the main fluid passage 32 in the pump housing 30. In a further alternative, the bearing 42 in the bore 38 of the pump housing 30 may be positioned between the annular channel 66 and the pulley 20.

The present invention has particular application with the engine of a motor vehicle, although it will be appreciated that the invention may be used with engines having alternative applications.

Claims

1. A combined pump and electric generator comprising a pump housing having a main fluid passage with a fluid inlet and a fluid outlet; a generator housing secured to the pump housing; a shaft extending through the pump housing, through the main fluid passage in the pump housing, and through the generator housing, and having a longitudinal axis; a rotor winding secured to the shaft inside the generator housing; an annular stator winding secured inside the generator housing around the rotor winding; pump vanes secured to the shaft inside the main fluid passage; drive means secured to one end of the shaft outside of the pump housing and the generator housing for rotating the shaft about the longitudinal axis; a coolant bore extending substantially longitudinally through the shaft; and a second fluid passage fluidly connecting the coolant bore in the shaft with the main fluid passage in the pump housing.

2. A combined pump and electric generator as claimed in Claim 1, wherein the shaft extends through a bore formed in the pump housing.

3. A combined pump and electric generator as claimed in Claim 2, wherein the coolant bore in the shaft has a radially extending portion which opens into a sealed annular channel in the bore in the pump housing, the annular channel being fluidly connected with the second fluid passage.

4. A combined pump and electric generator as claimed in any one of Claims I to 3, wherein the second fluid passage is formed in the pump housing.

5. A combined pump and electric generator as claimed in any one of Claims 1 to 4, wherein the second fluid passage opens into the main fluid passage between the pump vanes and the fluid outlet.

6 6. A combined pump and electric generator as claimed in any one of Claims 1 to 5, wherein the other end of the shaft is locatable in a sealed aperture in an engine block having a coolant fluid passage; and wherein the coolant bore in the shaft extends through the other end of the shaft to be capable of opening into the coolant fluid passage.

7. A combined pump and electric generator as claimed in any one of Claims 1 to 6, wherein the generator housing has a fluid channel formed therein, one end of the fluid channel opening into the main fluid passage in the pump housing.

8. A combined pump and electric generator as claimed in Claim 7, wherein the other end of the fluid channel in the generator housing is fluidly connectable to a coolant fluid passage in an engine block.

9. A combined pump and electric generator as claimed in any one of Claims 1 to 8, wherein the drive means is positioned adjacent the pump housing.

10. A combined pump and electric generator as claimed in any one of Claims 1 to 9, wherein the drive means is a pulley.

11. A combined pump and electric generator substantially as herein described with reference to, and as shown in, the accompanying drawing.