GB1566176A

GB1566176A - Apparatus having a rolling bearing and means for lubricating the bearing

Info

Publication number: GB1566176A
Application number: GB4418977A
Authority: GB
Original assignee: SKF Kugellagerfabriken GmbH
Current assignee: SKF GmbH
Priority date: 1976-07-23
Filing date: 1977-10-24
Publication date: 1980-04-30

Description

(54) APPARATUS HAVING A ROLLING BEARING AND MEANS FOR LUBRICATING THE BEARING (71) We, SKF KUGELLAGERFABRIKEN GESELLSCHAFT MIT BESCHRANKTER HAF TU, a German Body Corporate, of Ernst SaOStiave 8720 Schwcinfurt 2, German Federal Republic, do hereby declare the invention,, for which we pray that a patent may be granted to us, and the method by which it is to be performed, to be particularly described in and by the following statenent : - This invention is concerned with apparatus having a rolling bearing and means for lubricating the bearing.

The invention provides apparatus having a rolling bearing and: means for lubricating the bearing the apparatus comprising a housing, a shaft extending within the housing, a rolling bearing located in the housing and around the shaft and supporting the shaft for rotation about its longitudinal axis with respect to the housing, a lubricant chamber, aiid two elements, the first element being an annular disc fixed to the shaft for non rotation with respect to the shaft, the second element being a ring fixed in the housing for non-rotation with respect to the housing, the twu elements having facing co,operating sur facia one of which has a plurality of channels extending both circumferentially and radially with respect to the shaft axis, and t3e lubricant clamber being an annular re cress in the housing extending circumferen tizzy around the facing surfaces of the disc and the ring, which chamber is supplied with lubricant and communicates with the facing surfaces of the two elements, all such that upon relative rotation of the shaft in a particular direction with respect to the housing and hence relative rotation between the facing surfaces of the two elements.

licant in the chamber is conveyed from the. chamber away to between the facing .sFrfe of the two elements by hydrodynamic action for eventual discharge ad Jaeent to tise r1Iing members. o. the bear- ing.

There may be two rings, one on each axial sides of the disc. The two rings may extend radially outwardly past the annular disc and may be rigidly interconnected by way of their radially outer portions, and there may be radially extending apertures between the rings allowing the passage of lubricant from the lubricant chamber to between the facing surfaces of the annular disc and the rings.

A sleeve may be fixed to the housing radially inside of the annular lubricant chamber, and the sleeve may have radially extending apertures allowing passage of lubricant from the lubricant chamber. The sleeve may fix the or each ring for non-rotation with respect to the housing but allow axial movement of the or each ring.

The ring may have or with a part of the bearing form an axially extending passage or passages to convey the lubricant from between the facing surfaces of the ring and disc to the rolling members of the bearing.

The ring may form an axially extending annular passage with a relatively rotatable part of the bearing and one of the facing surfaces of the ring and relatively rotatable part of the bearing may have channels in its surface extending both axially and circumferentially to produce upon relative rotation of those facing surfaces a hydrodynamic action which conveys the lubricant along the passage.

An embodiment of the invention will be described hereinafter with reference to the accompanying drawings wherein: Fig. 1 is an axial section through apparatus according to the invention, and Fig. 2 is an axial section in a different plane through the apparatus shown in Fig 1, the section being at the place where the two rings are secured.

Referring to Figs. I and 2, a pumping disc 1 is secured to a shaft 4 between two taper-roller bearings 2, 3 disposed on each side of the disc 1; the disc is clamped between inner race rings 6 of the two bearings 2, 3 by means of a sleeve 5 pushed axially on to shaft 4. Each bearing Z 3 comprises an inner race ring 6, an outer race ring 9 secured in a bore 7 of a casing or housing 8, and taper rollers 11 guided in a cage 10. Disc 1 has on both sides a pumping surface 12 which faces the associated bearing 2 or 3 and which is formed with skew or helical grooves 13.

A sleeve 14 is secured in casing bore 7, e.g. by a press fit, between the outer race rings 9 of the two bearings 2, 3.

Two rings 15 so extend around disc 1 that each of the two pumping surfaces 12 is disposed opposite and close to a cooperating surface 16 of the associated ring 15. As can be seen clearly in Fig. 2, the two rings 15 are rigidly interconnected by way of their outer edges by screws 17 which engaging in radial projections 18. The projections 18 of the two rings 15 extend into a recess 19 in sleeve 14 so that the two rings 15 are nonrotatably mounted in the casing 8. For the rest, the rings 15 can move axially in the bore of sleeve 14.

The outside edge of each ring 15 is formed with radial orifices 20 which, together with radial orifices 21 in the sleeve 14, enable the surfaces 16 to communicate with an annular chamber 22 contrived in bore 7. Lubricant can be supplied to chamber 22 through a supply passage 23 in casing 8.

In their radially inward region the two rings 15 cooperate with radially outer surfaces 24 of the associated inner ring 6 to bound an axial gap 25 which continues the radial gap bounded by the surfaces 12 and 16 and terminates near the taper rollers 11.

In operation, lubricant goes from the lubricant-supplied chamber 22 through the orifices 21, 20 into the gap bounded by the surfaces 12 and 16. Since disc 1 rotates in a particular direction with the shaft 4, there is a relative movement between surface 12 of disc 1 and the closely adjacent cooperating surface 16 of the ring 15, so that the hydrodynamically operative grooves 13 pump the lubricant radially inwards from the outside edge of disc 1 into the adjacent axial gap 25 between the ring 15 and the outside surface 24 of the corresponding inner ring 6. The lubricant flows through the axial gap 25 and emerges therefrom near the taper rollers 11 to lubricate the bearings 2 3.

The apparatus according to the invention has the great advantage that the bearings 2, 3 receive an adequate amount of lubricant continuously and there is no harmful abrasion in the lubricating system.

The described embodiment of the invention can be varied so that the pair of rolling bearings can be replaced by a single rolling bearing, in which event the pumping disc has a pumping surface only on one side-the side near the rolling bearing. Also, to increase the pumping effect the outside surface 24 of the inner ring 6 or that surface of the associated ring 15 which cooperates with the surface 24 can be formed axially of the rolling bearing with hydrodynamically pumping skew or helical grooves. The surface 12 of the disc 1 need not necessarily be perpendicular to the axis of the shaft 4 but can, with the opposite cooperating surface of the associated ring, be conical, so that the radially inwards end of the gap between the pumping surface and the cooperating surface terminates near the rolling bearing concerned. Instead of being formed with an axial gap, the or each ring can have in its bottom region axial passages through which the lubricant can go to the rolling bearing.

WHAT WE CLAIM IS:- 1. Apparatus having a rolling bearing and means for lubricating the bearing, the apparatus comprising a housing, a shaft extending within the housing, a rolling bearing located in the housing and around the shaft and supporting the shaft for rotation about its longitudinal axis with respect to the housing, a lubricant chamber, and two elements, the first element being an annular disc fixed to the shaft for nonrotation with respect to the shaft, the second element being a ring fixed in the housing for non-rotation with respect to the housing, the two elements having facing co-operating surfaces one of which has a plurality of channels extending both circumferentially and radially with respect to the shaft axis, and the lubricant chamber being an annular recess in the housing extending circumferentially around the facing surfaces of the disc and the ring, which chamber is supplied with lubricant and communicates with the facing surfaces of the two channels, all such that upon relative rotation of the shaft in a particular direction with respect to the housing and hence relative rotation between the facing surfaces of the two elements, lubricant in the chamber is conveyed from the chamber away between the facing surfaces of the two elements by hydrodynamic action for eventual discharge adjacent to the rolling members of the bearing.

2. Apparatus as claimed in claim 1 wherein there are two rings, one on each axial side of the disc.

3. Apparatus as claimed in claim 2 wherein the two rings extend radially outwardly past the annular disc and are rigidly interconnected by way of their radially outer portions, there being radially extending apertures between the rings allowing the passage of lubricant from the lubricant chamber to between the facing surfaces of the annular disc and the rings.

4. Apparatus as claimed in any one of claims 1 to 3 wherein a sleeve is fixed to the

**WARNING** end of DESC field may overlap start of CLMS **.

Claims

**WARNING** start of CLMS field may overlap end of DESC **. ring 9 secured in a bore 7 of a casing or housing 8, and taper rollers 11 guided in a cage 10. Disc 1 has on both sides a pumping surface 12 which faces the associated bearing 2 or 3 and which is formed with skew or helical grooves 13. A sleeve 14 is secured in casing bore 7, e.g. by a press fit, between the outer race rings 9 of the two bearings 2, 3. Two rings 15 so extend around disc 1 that each of the two pumping surfaces 12 is disposed opposite and close to a cooperating surface 16 of the associated ring 15. As can be seen clearly in Fig. 2, the two rings 15 are rigidly interconnected by way of their outer edges by screws 17 which engaging in radial projections 18. The projections 18 of the two rings 15 extend into a recess 19 in sleeve 14 so that the two rings 15 are nonrotatably mounted in the casing 8. For the rest, the rings 15 can move axially in the bore of sleeve 14. The outside edge of each ring 15 is formed with radial orifices 20 which, together with radial orifices 21 in the sleeve 14, enable the surfaces 16 to communicate with an annular chamber 22 contrived in bore 7. Lubricant can be supplied to chamber 22 through a supply passage 23 in casing 8. In their radially inward region the two rings 15 cooperate with radially outer surfaces 24 of the associated inner ring 6 to bound an axial gap 25 which continues the radial gap bounded by the surfaces 12 and 16 and terminates near the taper rollers 11. In operation, lubricant goes from the lubricant-supplied chamber 22 through the orifices 21, 20 into the gap bounded by the surfaces 12 and 16. Since disc 1 rotates in a particular direction with the shaft 4, there is a relative movement between surface 12 of disc 1 and the closely adjacent cooperating surface 16 of the ring 15, so that the hydrodynamically operative grooves 13 pump the lubricant radially inwards from the outside edge of disc 1 into the adjacent axial gap 25 between the ring 15 and the outside surface 24 of the corresponding inner ring 6. The lubricant flows through the axial gap 25 and emerges therefrom near the taper rollers 11 to lubricate the bearings 2 3. The apparatus according to the invention has the great advantage that the bearings 2, 3 receive an adequate amount of lubricant continuously and there is no harmful abrasion in the lubricating system. The described embodiment of the invention can be varied so that the pair of rolling bearings can be replaced by a single rolling bearing, in which event the pumping disc has a pumping surface only on one side-the side near the rolling bearing. Also, to increase the pumping effect the outside surface 24 of the inner ring 6 or that surface of the associated ring 15 which cooperates with the surface 24 can be formed axially of the rolling bearing with hydrodynamically pumping skew or helical grooves. The surface 12 of the disc 1 need not necessarily be perpendicular to the axis of the shaft 4 but can, with the opposite cooperating surface of the associated ring, be conical, so that the radially inwards end of the gap between the pumping surface and the cooperating surface terminates near the rolling bearing concerned. Instead of being formed with an axial gap, the or each ring can have in its bottom region axial passages through which the lubricant can go to the rolling bearing. WHAT WE CLAIM IS:-

1. Apparatus having a rolling bearing and means for lubricating the bearing, the apparatus comprising a housing, a shaft extending within the housing, a rolling bearing located in the housing and around the shaft and supporting the shaft for rotation about its longitudinal axis with respect to the housing, a lubricant chamber, and two elements, the first element being an annular disc fixed to the shaft for nonrotation with respect to the shaft, the second element being a ring fixed in the housing for non-rotation with respect to the housing, the two elements having facing co-operating surfaces one of which has a plurality of channels extending both circumferentially and radially with respect to the shaft axis, and the lubricant chamber being an annular recess in the housing extending circumferentially around the facing surfaces of the disc and the ring, which chamber is supplied with lubricant and communicates with the facing surfaces of the two channels, all such that upon relative rotation of the shaft in a particular direction with respect to the housing and hence relative rotation between the facing surfaces of the two elements, lubricant in the chamber is conveyed from the chamber away between the facing surfaces of the two elements by hydrodynamic action for eventual discharge adjacent to the rolling members of the bearing.

housing radially inside of the annular lubricant chamber, the sleeve having radially extending apertures allowing passage of lubricant from the lubricant chamber.

5. Apparatus as claimed in claim 4 wherein the sleeve fixes the or each ring for non-rotation with respect to the housing but allows axial movement of the or each ring.

6. Apparatus as claimed in any one of claims 1 to 5 wherein the ring has or with a part of the bearing forms an axially extending passage or passages to convey the lubricant from between the facing surfaces of the ring and disc to the rolling members of the bearing.

7. Apparatus as claimed in claim 6 wherein the ring forms an axially extending annular passage with a relatively rotatable part of the bearing, one of the facing surfaces of the ring and relatively rotatable part of the bearing having channels in its surface extending both axially and circumferentially to produce upon relative rotation of these facing surfaces a hydrodynamic action which conveys the lubricant along the passage.

8. Apparatus substantially as herein described with reference to and as shown in the accompanying drawings.