Hybrid roller bearing, particularly for refrigerant compressor

Patent metadata

Field	Value
Publication number	US-10280973-B1
Application number	US-201715848868-A
Country	US
Kind code	B1
Filing date	Dec 20, 2017
Priority date	Dec 20, 2017
Publication date	May 7, 2019
Grant date	May 7, 2019

Abstract

A hybrid roller bearing having an inner raceway and an outer raceway and a plurality of rollers arranged therebetween. The inner raceway and the outer raceway are made from bearing steel and have a first surface RMS roughness R q1 . At least one roller is made from a ceramic material and has at least at the roller raceway a second surface RMS roughness R q2 . The roughness of the raceways R q1 is 1.2 to 4 times higher than the roughness R q2 of the at least one roller, as well as a refrigerant compressor with such a hybrid roller bearing.

First claim

What is claimed is:

1. A hybrid roller bearing comprising:
an inner raceway,
an outer raceway, and
a plurality of rollers arranged therebetween, wherein
the inner raceway and the outer raceway are made from bearing steel and have a first surface RMS roughness R q1 , wherein
at least one roller is made from a ceramic material and has at least at a rolling surface a second surface RMS roughness R q2 , and wherein
the roughness of the raceways R q1 is 1.2 to 4 times higher than the roughness R q2 of the at least one roller.

2. The hybrid roller bearing according to claim 1 , wherein a combined roughness skewness of the raceways and the rollers is less than 0.

3. The hybrid roller bearing according to claim 1 , wherein a combined roughness slope parameter of the raceways and the rollers is ≤50 [mrad].

4. The hybrid roller bearing according claim 1 , wherein an osculation Φ of the hybrid roller bearing ranges between 1.02 and 1.1, wherein Φ is defined as

Φ
=

2
⁢

r

i
,
e

D
w

,

with r i,e being the raceway radius of the inner raceway or the outer raceway, and D w being the diameter of the roller.

5. The hybrid roller bearing according to claim 1 , wherein at least one raceway is made from a hardened corrosion-resistant steel, having a corrosion resistance with a pitting potential of at least 25 mV higher than the stainless steel reference (AISI 440C) according to ASTM G61-86.

6. The hybrid roller bearing according to claim 1 , wherein at least one roller is made from silicon nitride (Si 3 N 4 ).

7. The hybrid roller bearing according to claim 1 , wherein the rollers are encompassed by a cage.

8. The hybrid roller bearing according to claim 1 , wherein the hybrid roller bearing is lubricated by means of an ultra-thin lubrication film arranged between the rollers and the raceways, and wherein the lubrication film thickness is less than 300 nm.

9. The hybrid roller bearing according claim 8 , wherein the hybrid roller bearing is lubricated with pure refrigerant or a refrigerant/oil mixture forming an elasto-hydrodynamic lubricant film between the rollers and the raceways.

10. The hybrid roller bearing according to claim 1 , wherein the rollers are encompassed by a cage that is made from a fiber-enforced material.

11. A refrigerant compressor comprising:
at least one hybrid roller bearing having:
an inner raceway,
an outer raceway, and
a plurality of rollers arranged between the inner raceway and the outer raceway, wherein
the inner raceway and the outer raceway are made from bearing steel and have a first surface RMS roughness R q1 , wherein
at least one roller is made from a ceramic material and has at least at a rolling surface a second surface RMS roughness R q2 , and wherein
the roughness of the raceways R q1 is 1.2 to 4 times higher than the roughness R q2 of the at least one roller.

Assignees

• Skf Ab

Inventors

• Hauleitner Rudolf
• Morales Espejel Guillermo Enrique
• Kerrigan Aidan
• Wallin Hans

Classifications

• F16C33/585

  of raceways, e.g. ribs to guide the rollers · CPC title

• F16C33/34

  Rollers; Needles · CPC title

• F16C33/66

  Special parts or details in view of lubrication · CPC title

• F16C19/54

  Systems consisting of a plurality of bearings with rolling friction (spindle bearings F16C35/08) · CPC title

• F16C2240/54

  Surface roughness · CPC title