Method for estimating the size of a surface defect of a bearing, and associated bearing device
OwnerElizabertus MALJAARS, Hendrik Anne MOL +3inventors
InventorsElizabertus MALJAARS, Hendrik Anne MOL, Gerrit-Jan DOP, Johannes RAVESLOOT, Arjen Cornelis Franciscus JANSSEN
Life of this patent
Estimating the term…
Abstract
A device (8) for estimating the size of a surface defect of a bearing (6). The device (8) includes a conditioning means (13), a first determining means (14), a second determining means (15), a solving means (16), a comparing means (17), a detecting means (18), and a third determining means (19).
Claims16
A method for estimating the size of a surface defect of a bearing, the bearing comprising a stationary ring and a rotating ring capable of rotating concentrically relative to the stationary ring and rolling elements interposed between the stationary and rotating rings, the method comprising:
- measuring, with at least one strain sensor comprising a detection cell, the length of the detection cell of the sensor in the circumferential direction being smaller than the circumferential distance between two adjacent rolling elements projected on the stationary ring, strain values caused by rolling element forces on the stationary ring according to one position parameter comprising a rolling element position parameter representative of the position of the rolling elements relative to the at least one strain sensor, in particular spread in a loaded zone of the bearing,
- determining intervals of position parameter values when rolling element position parameter values are associated to a maximum strain magnitude within a predetermined value, the maximum strain magnitude being equal to the maximum value of the strain values, the length of each interval being equal to a predetermined length,
- determining a linear equation between the strain magnitudes of the intervals of position parameter values, a carrier function, and cyclostationary contact forces applied on at least one of the stationary ring, the rotating ring or rolling elements,
- solving the linear equation to determine the cyclostationary contact forces applied on said at least one of the stationary ring, the rotating ring or rolling elements,
- comparing the determined cyclostationary contact forces to a detection threshold,
- detecting a surface defect on said at least the stationary ring, the rotating ring or rolling elements if the value of the cyclostationary contact forces is smaller than the detection threshold, and
- determining the size of the surface defect from the intervals of position parameter from the position parameter values associated with cyclostationary contact forces smaller than the detection threshold, the size of the surface defect comprising the depth of the said defect, the depth being determined from the minimal value of the cyclostationary contact forces.
A device for estimating the size of a surface defect of a bearing, the bearing comprising a stationary ring and a rotating ring capable of rotating concentrically relative to the stationary ring, and rolling elements interposed between the stationary and rotating rings, the device comprising:
- a conditioning means configured to determine strain values from signals delivered by at least one strain sensor comprising a detection cell, the length of the detection cell of the sensor in the circumferential direction being smaller than the circumferential distance between two adjacent rolling elements projected on the stationary ring, the strain values being caused by rolling element forces on the stationary ring, and to associate each strain value to at least one position parameter value comprising a rolling element position parameter representative of the position of the rolling elements relative to the at least one strain sensor,
- a first determining means configured to determine intervals of position parameter values when rolling element position parameter values are associated to a maximum strain magnitude within a predetermined value, the maximum strain magnitude being equal to the maximum value of the strain values, the length of each interval being equal to a predetermined length,
- a second determining means configured to determine a linear equation between the strain magnitudes of the intervals of position parameter values, a carrier function, and cyclostationary contact forces applied on at least one of the stationary ring, the rotating ring or rolling elements,
- a solving means configured to solve the linear equation to determine the cyclostationary contact forces applied on said at least one of the stationary ring, the rotating ring or rolling elements,
- a comparing means configured to compare the determined cyclostationary contact forces to a detection threshold,
- a detecting means configured to detect a surface defect on said at least the stationary ring, the rotating ring or rolling elements if the value of the cyclostationary contact forces is smaller than the detection threshold, and
- a third determining means configured to determine the size of the surface defect from the intervals of position parameter from the position parameter values associated with cyclostationary contact forces smaller than the detection threshold, the size of the surface defect comprising the depth of the said defect, the depth being determined from the minimal value of the cyclostationary contact forces.
Dependencies are inferred from the claim text.