Oil pump of vehicle having inner ring

Abstract

The present disclosure provides an oil pump including a housing in which a space is formed, a rotor installed to be rotatable in an eccentric position in the housing and having vanes mounted along a circumference direction to be protruded and retracted in a radial direction of the housing, and an inner ring fitted to an inner surface of the housing and rotated along with the rotor when the rotor rotates. The housing is formed of a material harder than the material of the inner ring, and oil for lubrication is provided between the housing and the inner ring.

Claims

1. An oil pump for a vehicle, the oil pump comprising: a housing forming a space; a rotor installed to be rotatable in an eccentric position in the housing, the rotor having vanes mounted along a circumferential direction to be protruded and retracted in a radial direction of the housing; and an inner ring fitted to an inner surface of the housing, the inner ring configured to rotate along with the rotor when the rotor rotates, wherein: a first groove is formed on the inner surface of the housing along the circumferential direction of the housing, a second groove is formed on an outer surface of the inner ring along the circumferential direction, the first groove and the second groove are configured to flow oil between the inner ring and the housing and reduce a friction between the inner ring and the housing, the housing is formed of a material harder than the inner ring, the inner ring is configured to rotate in the same direction as the vanes rotate when the rotor rotates, and the inner ring is configured to rotate along with the vanes when the vanes rotate, and the inner ring is configured to rotate later than the rotor.

2. The oil pump of claim 1, wherein the housing is made of synthetic resin material.

3. The oil pump of claim 2, wherein the housing is made of thermosetting phenolic resin material.

4. The oil pump of claim 1, wherein the housing is made of a light metal having a specific gravity lower than gravity of steel.

5. The oil pump of claim 1, wherein the inner ring is made of the same material as the vanes.

6. The oil pump of claim 1, wherein the housing is provided with at least an oil supply hole for supplying oil between the inner surface of the housing and the inner ring.

7. The oil pump of claim 1, wherein an outer surface of the housing is provided with at least one pocket formed concavely from the outside of the housing to the inner surface of the housing.

8. The oil pump of claim 7, wherein the at least one pocket comprises a plurality of pockets that is formed along the circumferential direction and a height direction of the housing.

9. The oil pump of claim 1, wherein the vanes are slidable in the radial direction and installed at intervals along the circumferential direction.

10. The oil pump of claim 1, wherein the inner ring is formed in a cylinder shape to be fitted to the inner surface of the housing.

11. The oil pump of claim 1, wherein the first groove is formed in a spiral pattern on the inner surface of the housing and configured to supply the oil between the housing and the inner ring.

Description

DRAWINGS

(1) In order that the disclosure may be well understood, there will now be described various forms thereof, given by way of example, reference being made to the accompanying drawings, in which:

(2) FIG. 1 is a plane view of an oil pump according to a prior art;

(3) FIG. 2 is a plan view showing an oil pump with an inner ring according to an exemplary form of the present disclosure;

(4) FIG. 3 is an exploded perspective view of a housing and an inner ring in the oil pump according to the exemplary form of the present disclosure;

(5) FIG. 4 is a partially cut-away perspective view of the oil pump according to the exemplary form of the present disclosure; and

(6) FIG. 5 is a perspective view of a groove with a spiral shape formed in a housing of an oil pump according to another exemplary form of the present disclosure.

(7) The drawings described herein are for illustration purposes only and are not intended to limit the scope of the present disclosure in any way.

DETAILED DESCRIPTION

(8) The following description is merely exemplary in nature and is not intended to limit the present disclosure, application, or uses. It should be understood that throughout the drawings, corresponding reference numerals indicate like or corresponding parts and features.

(9) Referring to FIG. 2, an oil pump 10 having an inner ring 14 according to the present disclosure may include a housing 11 in which a space is formed, a rotor 12 being installed to be rotatable in an eccentric position on the housing 11 and having vanes 13 mounted along a circumference direction to be protruded and retracted in a radial direction of the housing 11, and the inner ring 14 which is fitted to an inner surface of the housing 11 and rotates along the rotor 12 when the rotor 12 rotates. The housing 11 may be formed of a material harder than the inner ring 14, and oil for lubrication may be accommodated between the housing 11 and the inner ring 14.

(10) The space may be formed in the housing 11. Constituent elements described below may be provided in the space of the housing 11.

(11) The rotor 12 may be installed to be rotatable in an eccentrically located position on the housing 11 and have the vane 13 mounted along a circumference direction to be protruded and retracted in a radial direction of the housing 11.

(12) The inner ring 14 may be fitted to the inner surface of the housing 11. The inner ring 14 may rotate along the rotor 12 when the rotor 12 rotates. The inner ring 14 may be contact with the rotating vane 13 and formed into a cylinder shape to be fitted to the inner surface of the housing 11.

(13) As shown in FIG. 2, when the rotor 12 rotates, the inner ring 14 may rotate in the same direction as the vane 13. Since the inner ring 14 rotates along the vane 13 when the vane 13 rotates, the inner ring 14 rotates at a later rotation speed than the rotor 12.

(14) The inner ring 14 and the housing 11 may be the duality structure, so that the fixed housing 11 may be formed of lightweight material and the inner ring 14 directly contacting with the rotating vane 13 may be formed of a material having a higher strength than the housing 11. More specifically, the housing 11 may be formed of synthetic resin or light metal material, and the housing 11 may be made of thermosetting phenolic resin material in synthetic resin and also, a light metal having a specific gravity lower than that of steel, for example, aluminum or magnesium.

(15) The inner ring 14 may be made of material that is stronger than the housing 11, for example steel. Preferably, the inner ring 14 may made of bearing steel or tool steel that is the same material as the vane 13 because the vane 13 may also be made of bearing steel or tool steel. The bearing steel and tool steel have excellent abrasion resistance, which can reduce the abrasion between the vane 13 and the inner ring 14 contacted with each other.

(16) Accordingly, since the housing 11 is made of a lightweight material and the inner ring 14 contacting the vane 13 is made of a high-strength material, the weight of the oil pump 10 can be reduced and fuel consumption can be improved.

(17) When the rotor 12 rotates with the inner ring 14 together, lubrication is desired between the housing 11 and the inner ring 14. For this purpose, an oil film is formed to contain oil between the housing 11 and the inner ring 14.

(18) Particularly, in FIG. 3, at least one first groove 11b is formed on the inner surface of the housing 11 along a height direction H and at least one second groove 14a is formed on an outer circumference surface of the inner ring 14 along the height direction H. When the oil pump 10 is assembled according to the present disclosure, at least one of the first groove 11b in the housing 11 and second groove 14a in the inner ring 14 may be formed for receiving oil. Since the oil is provided inside each of the grooves 11b and 14a, friction between the inner ring 14 and the housing 11 is reduced by the oil while the inner ring 14 rotates in the housing 11.

(19) For example, as shown in FIG. 3, the first groove 11b may be formed on the inner surface of the housing 11. The first groove 11b may be formed along the circumference direction of the housing 11 at a predetermined depth. In FIG. 3, a plurality of the first grooves 11b in the housing 11 may be formed along the height direction H of the housing 11.

(20) On the other hand, the second groove 14a may also be formed on the outer circumference surface of the inner ring 14. A plurality of second grooves 14a in the inner ring 14 may also be formed along the height direction H of the inner ring 14.

(21) The housing 11 may be provided with at least one oil supply hole 11a for supplying oil desired for lubrication between the housing 11 and the inner ring 14. The oil supply holes 11a may be formed through the wall of the housing 11 so that oil is supplied from the outside of the housing 11 to the inner surface of the housing 11 for lubricating between the housing 11 and the inner ring 14.

(22) The oil may also be supplied through the surface where the oil pump 10 is assembled. FIG. 4 shows the area where the oil is supplied for the lubrication of the oil pump 10 by arrows. The oil may be supplied through the oil supply hole 11a (solid line in FIG. 4) and also be supplied through the surface on which the oil pump 10 is assembled (dotted arrow in FIG. 4).

(23) On the outer surface of the housing 11, at least one pocket 11c may be formed concavely from the outer surface of the housing 11 along the circumference direction and the height direction H of the housing 11.

(24) The pockets 11c are configured for serving to buffer the pressure wave generated by the oil pressurized by and discharged from the oil pump 10 during operation of the oil pump 10. These pockets 11c may be formed in the housing 11 along the circumference direction and the height direction H of the housing 11 for buffering the pressure wave generated when the pressurized oil is discharged from the oil pump 10, thereby improving NVH (Noise, Vibration and Harshness) performance.

(25) FIG. 5 shows an oil pump housing having an inner ring (not shown) according to another exemplary form of the present disclosure.

(26) The present exemplary form has the same configuration as the oil pump described above except that another groove 21b of the housing 21 is formed in a different shape. As shown in FIG. 5, the groove 21b formed in the housing 21 may be formed in a spiral pattern along the inner surface of the housing 21 to supply oil between the housing 21 and the inner ring (not shown). Furthermore, the groove 21b with a spiral shape may also be formed in the inner ring (not shown).

(27) While this present disclosure has been described in connection with what is presently considered to be practical exemplary forms. It is to be understood that the present disclosure is not limited to the disclosed forms, but, on the contrary, it is intended to cover various modification and equivalent arrangements included within the spirit and scope of the present disclosure.