Method of measuring preload in a multirow bearing assembly
First Claim
1. A method of ascertaining preload in a first bearing assembly that accommodates rotation about an axis and has at least two rows of rolling elements organized such that the bearing assembly will transfer thrust loads in both axial directions, said method comprising:
- applying a single thrust force to the first bearing assembly such that the force is transferred through the assembly in one axial direction, with the force being at a magnitude sufficient to unseat the rolling elements of one of the rows;
applying a single thrust force to the first bearing assembly such that the force is transferred through the bearing assembly in the other axial direction, with that force being of a magnitude sufficient to unseat the rolling elements of the other row;
measuring the deflection that the first bearing assembly undergoes as a consequence of the thrust forces transferred through it; and
comparing the deflection of the first bearing assembly with a known deflection of a second bearing assembly of equivalent stiffness under equivalent thrust forces transferred through the second bearing assembly in both axial directions while the second bearing assembly is set to a condition of known end play.
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Accused Products
Abstract
The preload in a double row production bearing assembly is ascertained by comparing the deflection produced in that bearing assembly by oppositely directed thrust forces with the deflection produced in a master bearing assembly by equivalent thrust forces likewise applied in opposite directions. The master bearing assembly is similar in configuration and substantially equal in stiffness to the production bearing assembly, but exists in a state of end play. Each thrust force is transferred through the rolling elements of one row and should be sufficient in magnitude to unseat the rolling elements of the other row. The preload in the production bearing assembly equals the end play in the master bearing assembly plus the deflection in the production assembly less the deflection in the master assembly. The endplay in the master bearing assembly is ascertained by extrapolating the deflection to zero thrust force.
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Citations
30 Claims
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1. A method of ascertaining preload in a first bearing assembly that accommodates rotation about an axis and has at least two rows of rolling elements organized such that the bearing assembly will transfer thrust loads in both axial directions, said method comprising:
- applying a single thrust force to the first bearing assembly such that the force is transferred through the assembly in one axial direction, with the force being at a magnitude sufficient to unseat the rolling elements of one of the rows;
applying a single thrust force to the first bearing assembly such that the force is transferred through the bearing assembly in the other axial direction, with that force being of a magnitude sufficient to unseat the rolling elements of the other row;
measuring the deflection that the first bearing assembly undergoes as a consequence of the thrust forces transferred through it; and
comparing the deflection of the first bearing assembly with a known deflection of a second bearing assembly of equivalent stiffness under equivalent thrust forces transferred through the second bearing assembly in both axial directions while the second bearing assembly is set to a condition of known end play. - View Dependent Claims (2, 3, 4, 5, 6, 7)
- applying a single thrust force to the first bearing assembly such that the force is transferred through the assembly in one axial direction, with the force being at a magnitude sufficient to unseat the rolling elements of one of the rows;
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8. A method of ascertaining dimensional preload in a production bearing assembly having an outer component, an inner component, and rolling elements arranged in first and second rows between raceways of the two components, with the rolling elements and raceways for the first row being configured to transfer thrust forces between the inner and outer components in one axial direction and the rolling elements and raceways for the second row being configured to transfer thrust forces between the inner and outer components in the other axial direction, said method comprising:
- transferring a thrust force between the two components through the rolling elements of the first row, with the force being of a magnitude sufficient to unseat the rolling elements of the second row;
transferring a thrust force between the two components through the rolling elements of the second row, with the force being of a magnitude sufficient to unseat the rolling elements of the first row;
measuring the deflection of the first component relative to the second component as a consequence the transfer of the thrust forces through both rows of rolling elements; and
comparing the deflection in the production bearing assembly with the deflection in a master bearing assembly of similar configuration and stiffness, but having been set to a condition of known end play, with the deflections being compared at an equivalent thrust force transferred through the first row of rolling elements and another equivalent thrust force transferred through the second row of rolling elements in the master bearing assembly. - View Dependent Claims (9, 10, 11, 12, 13, 14, 15, 16, 17, 18)
- transferring a thrust force between the two components through the rolling elements of the first row, with the force being of a magnitude sufficient to unseat the rolling elements of the second row;
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19. A method of ascertaining dimensional preload in a production bearing assembly having an outer component, an inner component, and rolling elements arranged in first and second rows between raceways on the inner and outer components, with the rolling elements and raceways for the first row being configured to transfer thrust forces between the inner and outer components in one axial direction and the rolling elements and raceways of the second row being configured to transfer thrust forces between the inner and outer components in the other axial direction, said method comprising:
- establishing the deflection characteristics of a master bearing that is similar in configuration to the production bearing assembly and has substantially the same stiffness, but differs in that it is set to a condition of end play;
from the deflection characteristics of the master bearing, calculating the end play (Em) in the master bearing assembly;
transferring a first thrust force between the inner and outer components of the master assembly through the rolling elements of the first row;
transferring a second thrust force between the inner and outer components of the master assembly through the rolling elements of the second row;
calculating the deflection (Dm) in the master bearing assembly produced by the first and second thrust forces;
transferring a third thrust force equal to the first thrust force between the inner and outer components of the production assembly through the rolling elements of the first row for the production assembly, transferring a fourth thrust force equal to the second thrust force between the inner and outer components of the production assembly through the rolling elements of the second row for the production assembly;
measuring the deflection Dp produced in the production assembly by the third and fourth thrust forces transferred through its rolling elements; and
calculating the preload in the production bearing assembly according to the following formula;
- View Dependent Claims (20, 21, 22, 23, 24)
- establishing the deflection characteristics of a master bearing that is similar in configuration to the production bearing assembly and has substantially the same stiffness, but differs in that it is set to a condition of end play;
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25. A method of ascertaining preload in a first bearing assembly that accommodates rotation about an axis and has at least two rows of rolling elements organized such that the bearing assembly will transfer thrust loads in both axial directions, said method comprising:
- applying a thrust force to the first bearing assembly such that the force is transferred through the assembly in one axial direction;
applying a thrust force to the first bearing assembly such that the force is transferred through the bearing assembly in the other axial direction;
measuring the deflection that the first bearing assembly undergoes as a consequence of the thrust forces transferred through it; and
comparing the deflection of the first bearing assembly with a known deflection of a second bearing assembly under known thrust forces transferred through the second bearing assembly in both axial directions while the second bearing assembly is set to a condition of known end play, with the deflections being compared according to the following formula;
- applying a thrust force to the first bearing assembly such that the force is transferred through the assembly in one axial direction;
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26. A method of ascertaining preload in a first bearing assembly that accommodates rotation about an axis and has at least two rows of rolling elements organized such that the bearing assembly will transfer thrust loads in both axial directions, said method comprising:
- applying a thrust force to the first bearing assembly such that the force is transferred through the assembly in one axial direction;
applying a thrust force to the first bearing assembly such that the force is transferred through the bearing assembly in the other axial direction, the forces in both axial directions being the same, the force applied in either direction being transferred through one of the rows of rolling elements and being of a magnitude sufficient to unseat the rolling elements at the other row of rolling elements;
measuring the deflection that the first bearing assembly undergoes as a consequence of the thrust forces transferred through it; and
comparing the deflection of the first bearing assembly with a known deflection of a second bearing assembly under thrust forces that are the same as the thrust forces transferred through the first bearing assembly and are transferred through the second bearing assembly in both axial directions while the second bearing assembly is set to a condition of known end play. - View Dependent Claims (29)
- applying a thrust force to the first bearing assembly such that the force is transferred through the assembly in one axial direction;
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27. A method of ascertaining preload in a first bearing assembly that accommodates rotation about an axis and has a unitary inner component, an outer component and at least two rows of rolling elements organized between the inner and outer components such that the bearing assembly will transfer thrust loads in both axial directions, said method comprising:
- applying a thrust force to the first bearing assembly such that the force is transferred through the assembly in one axial direction;
applying a thrust force to the first bearing assembly such that the force is transferred through the bearing assembly in the other axial direction;
measuring the deflection that the first bearing assembly undergoes as a consequence of the thrust forces transferred through it; and
comparing the deflection of the first bearing assembly with a known deflection of a second bearing assembly under known thrust forces transferred through the second bearing assembly in both axial directions while the second bearing assembly is set to a condition of known end play, the second bearing assembly being essentially identical in configuration and stiffness to the first bearing assembly with the exception that its inner component is segmented such that one of the rows of rolling elements for the second bearing assembly is around one segment and the other row of rolling elements is around the other segment.
- applying a thrust force to the first bearing assembly such that the force is transferred through the assembly in one axial direction;
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28. A method of ascertaining dimensional preload in a production bearing assembly having an outer component, an inner component, and rolling elements arranged in first and second rows between raceways of the two components, with the rolling elements and raceways for the first row being configured to transfer thrust forces between the inner and outer components in one axial direction and the rolling elements and raceways for the second row being configured to transfer thrust forces between the inner and outer components in the other axial direction, said method comprising:
- transferring a thrust force between the two components through the rolling elements of the first row;
transferring a thrust force between the two components through the rolling elements of the second row;
measuring the deflection of the first component relative to the second component as a consequence the transfer of the thrust forces through both rows of rolling elements; and
comparing the deflection in the production bearing assembly with the deflection in a master bearing assembly of similar configuration and stiffness, but having been set to a condition of known end play, with the deflection of the master bearing assembly having been produced by thrust a force transferred through the first row of rolling elements and another thrust force transferred through the second row of rolling elements in the master bearing assembly, the deflections of the production and master bearing assemblies being compared according to the following formula;
- View Dependent Claims (30)
- transferring a thrust force between the two components through the rolling elements of the first row;
Specification